Adding upstream version 43.5.upstream/43.5upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

85 files changed, 37898 insertions, 0 deletions

diff --git a/lib/README.md b/lib/README.md
new file mode 100644
index 0000000..628c58e
--- /dev/null
+++ b/lib/README.md
@@ -0,0 +1,7 @@
+libgnomesoftware
+================
+
+This is a static library, and is not all API stable.
+
+Only the plugin headers installed into /usr/include/gnome-software should be
+considered API.
diff --git a/lib/gnome-software-private.h b/lib/gnome-software-private.h
new file mode 100644
index 0000000..1e3addf
--- /dev/null
+++ b/lib/gnome-software-private.h
@@ -0,0 +1,24 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2017 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#ifndef I_KNOW_THE_GNOME_SOFTWARE_API_IS_SUBJECT_TO_CHANGE
+#define I_KNOW_THE_GNOME_SOFTWARE_API_IS_SUBJECT_TO_CHANGE
+#endif
+
+#include <gnome-software.h>
+
+#include <gs-app-list-private.h>
+#include <gs-app-private.h>
+#include <gs-category-private.h>
+#include <gs-fedora-third-party.h>
+#include <gs-os-release.h>
+#include <gs-plugin-loader.h>
+#include <gs-plugin-loader-sync.h>
+#include <gs-plugin-private.h>
diff --git a/lib/gnome-software.h b/lib/gnome-software.h
new file mode 100644
index 0000000..b57e257
--- /dev/null
+++ b/lib/gnome-software.h
@@ -0,0 +1,41 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2016 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#ifndef I_KNOW_THE_GNOME_SOFTWARE_API_IS_SUBJECT_TO_CHANGE
+#error You have to define I_KNOW_THE_GNOME_SOFTWARE_API_IS_SUBJECT_TO_CHANGE
+#endif
+
+#include <gs-app.h>
+#include <gs-app-list.h>
+#include <gs-app-collation.h>
+#include <gs-app-permissions.h>
+#include <gs-app-query.h>
+#include <gs-category.h>
+#include <gs-category-manager.h>
+#include <gs-desktop-data.h>
+#include <gs-download-utils.h>
+#include <gs-enums.h>
+#include <gs-icon.h>
+#include <gs-metered.h>
+#include <gs-odrs-provider.h>
+#include <gs-os-release.h>
+#include <gs-plugin.h>
+#include <gs-plugin-helpers.h>
+#include <gs-plugin-job.h>
+#include <gs-plugin-job-list-apps.h>
+#include <gs-plugin-job-list-categories.h>
+#include <gs-plugin-job-list-distro-upgrades.h>
+#include <gs-plugin-job-manage-repository.h>
+#include <gs-plugin-job-refine.h>
+#include <gs-plugin-job-refresh-metadata.h>
+#include <gs-plugin-vfuncs.h>
+#include <gs-remote-icon.h>
+#include <gs-utils.h>
+#include <gs-worker-thread.h>
diff --git a/lib/gs-app-collation.h b/lib/gs-app-collation.h
new file mode 100644
index 0000000..876ae54
--- /dev/null
+++ b/lib/gs-app-collation.h
@@ -0,0 +1,21 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2017-2018 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib-object.h>
+
+#include "gs-app-list.h"
+
+G_BEGIN_DECLS
+
+GsAppList	*gs_app_get_related		(GsApp		*app);
+GsAppList	*gs_app_dup_addons		(GsApp		*app);
+GsAppList	*gs_app_get_history		(GsApp		*app);
+
+G_END_DECLS
diff --git a/lib/gs-app-list-private.h b/lib/gs-app-list-private.h
new file mode 100644
index 0000000..5335173
--- /dev/null
+++ b/lib/gs-app-list-private.h
@@ -0,0 +1,51 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2016 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include "gs-app-list.h"
+
+G_BEGIN_DECLS
+
+/**
+ * GsAppListFlags:
+ * @GS_APP_LIST_FLAG_NONE:			No flags set
+ * @GS_APP_LIST_FLAG_IS_TRUNCATED:		List has been truncated
+ * @GS_APP_LIST_FLAG_WATCH_APPS:		Applications will be monitored
+ * @GS_APP_LIST_FLAG_WATCH_APPS_RELATED:	Applications related apps will be monitored
+ * @GS_APP_LIST_FLAG_WATCH_APPS_ADDONS:		Applications addon apps will be monitored
+ *
+ * Flags used to describe the list.
+ **/
+typedef enum {
+	GS_APP_LIST_FLAG_NONE			= 0,
+	/* empty slot */
+	GS_APP_LIST_FLAG_IS_TRUNCATED		= 1 << 1,
+	GS_APP_LIST_FLAG_WATCH_APPS		= 1 << 2,
+	GS_APP_LIST_FLAG_WATCH_APPS_RELATED	= 1 << 3,
+	GS_APP_LIST_FLAG_WATCH_APPS_ADDONS	= 1 << 4,
+	GS_APP_LIST_FLAG_LAST  /*< skip >*/
+} GsAppListFlags;
+
+guint		 gs_app_list_get_size_peak	(GsAppList	*list);
+void		 gs_app_list_set_size_peak	(GsAppList	*list,
+						 guint		 size_peak);
+void		 gs_app_list_filter_duplicates	(GsAppList	*list,
+						 GsAppListFilterFlags flags);
+void		 gs_app_list_randomize		(GsAppList	*list);
+void		 gs_app_list_remove_all		(GsAppList	*list);
+void		 gs_app_list_truncate		(GsAppList	*list,
+						 guint		 length);
+gboolean	 gs_app_list_has_flag		(GsAppList	*list,
+						 GsAppListFlags	 flag);
+void		 gs_app_list_add_flag		(GsAppList	*list,
+						 GsAppListFlags	 flag);
+GsAppState	 gs_app_list_get_state		(GsAppList	*list);
+guint		 gs_app_list_get_progress	(GsAppList	*list);
+
+G_END_DECLS
diff --git a/lib/gs-app-list.c b/lib/gs-app-list.c
new file mode 100644
index 0000000..a5f6785
--- /dev/null
+++ b/lib/gs-app-list.c
@@ -0,0 +1,1025 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2013-2016 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2017-2018 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-app-list
+ * @title: GsAppList
+ * @include: gnome-software.h
+ * @stability: Unstable
+ * @short_description: An application list
+ *
+ * These functions provide a refcounted list of #GsApp objects.
+ */
+
+#include "config.h"
+
+#include <glib.h>
+
+#include "gs-app-private.h"
+#include "gs-app-list-private.h"
+#include "gs-app-collation.h"
+#include "gs-enums.h"
+
+struct _GsAppList
+{
+	GObject			 parent_instance;
+	GPtrArray		*array;
+	GMutex			 mutex;
+	guint			 size_peak;
+	GsAppListFlags		 flags;
+	GsAppState		 state;
+	guint			 progress;  /* 0–100 inclusive, or %GS_APP_PROGRESS_UNKNOWN */
+	guint			 custom_progress; /* overrides the 'progress', if not %GS_APP_PROGRESS_UNKNOWN */
+};
+
+G_DEFINE_TYPE (GsAppList, gs_app_list, G_TYPE_OBJECT)
+
+enum {
+	PROP_STATE = 1,
+	PROP_PROGRESS,
+	PROP_LAST
+};
+
+enum {
+	SIGNAL_APP_STATE_CHANGED,
+	SIGNAL_LAST
+};
+
+static guint signals [SIGNAL_LAST] = { 0 };
+
+/**
+ * gs_app_list_get_state:
+ * @list: A #GsAppList
+ *
+ * Gets the state of the list.
+ *
+ * This method will only return a valid result if gs_app_list_add_flag() has
+ * been called with %GS_APP_LIST_FLAG_WATCH_APPS.
+ *
+ * Returns: the #GsAppState, e.g. %GS_APP_STATE_INSTALLED
+ *
+ * Since: 3.30
+ **/
+GsAppState
+gs_app_list_get_state (GsAppList *list)
+{
+	g_return_val_if_fail (GS_IS_APP_LIST (list), GS_APP_STATE_UNKNOWN);
+	return list->state;
+}
+
+/**
+ * gs_app_list_get_progress:
+ * @list: A #GsAppList
+ *
+ * Gets the average percentage completion of all apps in the list. If any of the
+ * apps in the list has progress %GS_APP_PROGRESS_UNKNOWN, or if the app list
+ * is empty, %GS_APP_PROGRESS_UNKNOWN will be returned.
+ *
+ * This method will only return a valid result if gs_app_list_add_flag() has
+ * been called with %GS_APP_LIST_FLAG_WATCH_APPS.
+ *
+ * Returns: the percentage completion (0–100 inclusive), or %GS_APP_PROGRESS_UNKNOWN for unknown
+ *
+ * Since: 3.30
+ **/
+guint
+gs_app_list_get_progress (GsAppList *list)
+{
+	g_return_val_if_fail (GS_IS_APP_LIST (list), GS_APP_PROGRESS_UNKNOWN);
+	if (list->custom_progress != GS_APP_PROGRESS_UNKNOWN)
+		return list->custom_progress;
+	return list->progress;
+}
+
+static gboolean
+app_list_notify_progress_idle_cb (gpointer user_data)
+{
+	GsAppList *list = user_data;
+
+	g_object_notify (G_OBJECT (list), "progress");
+	g_object_unref (list);
+
+	return G_SOURCE_REMOVE;
+}
+
+/**
+ * gs_app_list_override_progress:
+ * @list: a #GsAppList
+ * @progress: a progress to set, between 0 and 100 inclusive, or %GS_APP_PROGRESS_UNKNOWN
+ *
+ * Override the progress property to be this value, or use %GS_APP_PROGRESS_UNKNOWN,
+ * to unset the override. This can be used when only the overall progress is known,
+ * instead of a per-application progress.
+ *
+ * Since: 42
+ **/
+void
+gs_app_list_override_progress (GsAppList *list,
+			       guint progress)
+{
+	g_return_if_fail (GS_IS_APP_LIST (list));
+
+	if (list->custom_progress != progress) {
+		list->custom_progress = progress;
+		g_idle_add (app_list_notify_progress_idle_cb, g_object_ref (list));
+	}
+}
+
+static void
+gs_app_list_add_watched_for_app (GsAppList *list, GPtrArray *apps, GsApp *app)
+{
+	if (list->flags & GS_APP_LIST_FLAG_WATCH_APPS)
+		g_ptr_array_add (apps, app);
+	if (list->flags & GS_APP_LIST_FLAG_WATCH_APPS_ADDONS) {
+		g_autoptr(GsAppList) list2 = gs_app_dup_addons (app);
+
+		for (guint i = 0; list2 != NULL && i < gs_app_list_length (list2); i++) {
+			GsApp *app2 = gs_app_list_index (list2, i);
+			g_ptr_array_add (apps, app2);
+		}
+	}
+	if (list->flags & GS_APP_LIST_FLAG_WATCH_APPS_RELATED) {
+		GsAppList *list2 = gs_app_get_related (app);
+		for (guint i = 0; i < gs_app_list_length (list2); i++) {
+			GsApp *app2 = gs_app_list_index (list2, i);
+			g_ptr_array_add (apps, app2);
+		}
+	}
+}
+
+static GPtrArray *
+gs_app_list_get_watched_for_app (GsAppList *list, GsApp *app)
+{
+	GPtrArray *apps = g_ptr_array_new ();
+	gs_app_list_add_watched_for_app (list, apps, app);
+	return apps;
+}
+
+static GPtrArray *
+gs_app_list_get_watched (GsAppList *list)
+{
+	GPtrArray *apps = g_ptr_array_new ();
+	for (guint i = 0; i < list->array->len; i++) {
+		GsApp *app_tmp = g_ptr_array_index (list->array, i);
+		gs_app_list_add_watched_for_app (list, apps, app_tmp);
+	}
+	return apps;
+}
+
+static void
+gs_app_list_invalidate_progress (GsAppList *self)
+{
+	guint progress = 0;
+	g_autoptr(GPtrArray) apps = gs_app_list_get_watched (self);
+
+	/* find the average percentage complete of the list */
+	if (apps->len > 0) {
+		guint64 pc_cnt = 0;
+		gboolean unknown_seen = FALSE;
+
+		for (guint i = 0; i < apps->len; i++) {
+			GsApp *app_tmp = g_ptr_array_index (apps, i);
+			guint app_progress = gs_app_get_progress (app_tmp);
+
+			if (app_progress == GS_APP_PROGRESS_UNKNOWN) {
+				unknown_seen = TRUE;
+				break;
+			}
+			pc_cnt += gs_app_get_progress (app_tmp);
+		}
+
+		progress = (!unknown_seen) ? pc_cnt / apps->len : GS_APP_PROGRESS_UNKNOWN;
+	} else {
+		progress = GS_APP_PROGRESS_UNKNOWN;
+	}
+
+	if (self->progress != progress) {
+		self->progress = progress;
+		g_object_notify (G_OBJECT (self), "progress");
+	}
+}
+
+static void
+gs_app_list_invalidate_state (GsAppList *self)
+{
+	GsAppState state = GS_APP_STATE_UNKNOWN;
+	g_autoptr(GPtrArray) apps = gs_app_list_get_watched (self);
+
+	/* find any action state of the list */
+	for (guint i = 0; i < apps->len; i++) {
+		GsApp *app_tmp = g_ptr_array_index (apps, i);
+		GsAppState state_tmp = gs_app_get_state (app_tmp);
+		if (state_tmp == GS_APP_STATE_INSTALLING ||
+		    state_tmp == GS_APP_STATE_REMOVING) {
+			state = state_tmp;
+			break;
+		}
+	}
+	if (self->state != state) {
+		self->state = state;
+		g_object_notify (G_OBJECT (self), "state");
+	}
+}
+
+static void
+gs_app_list_progress_notify_cb (GsApp *app, GParamSpec *pspec, GsAppList *self)
+{
+	gs_app_list_invalidate_progress (self);
+}
+
+static void
+gs_app_list_state_notify_cb (GsApp *app, GParamSpec *pspec, GsAppList *self)
+{
+	gs_app_list_invalidate_state (self);
+
+	g_signal_emit (self, signals[SIGNAL_APP_STATE_CHANGED], 0, app);
+}
+
+static void
+gs_app_list_maybe_watch_app (GsAppList *list, GsApp *app)
+{
+	g_autoptr(GPtrArray) apps = gs_app_list_get_watched_for_app (list, app);
+	for (guint i = 0; i < apps->len; i++) {
+		GsApp *app_tmp = g_ptr_array_index (apps, i);
+		g_signal_connect_object (app_tmp, "notify::progress",
+					 G_CALLBACK (gs_app_list_progress_notify_cb),
+					 list, 0);
+		g_signal_connect_object (app_tmp, "notify::state",
+					 G_CALLBACK (gs_app_list_state_notify_cb),
+					 list, 0);
+	}
+}
+
+static void
+gs_app_list_maybe_unwatch_app (GsAppList *list, GsApp *app)
+{
+	g_autoptr(GPtrArray) apps = gs_app_list_get_watched_for_app (list, app);
+	for (guint i = 0; i < apps->len; i++) {
+		GsApp *app_tmp = g_ptr_array_index (apps, i);
+		g_signal_handlers_disconnect_by_data (app_tmp, list);
+	}
+}
+
+/**
+ * gs_app_list_get_size_peak:
+ * @list: A #GsAppList
+ *
+ * Returns the largest size the list has ever been.
+ *
+ * Returns: integer
+ *
+ * Since: 3.24
+ **/
+guint
+gs_app_list_get_size_peak (GsAppList *list)
+{
+	return list->size_peak;
+}
+
+/**
+ * gs_app_list_set_size_peak:
+ * @list: A #GsAppList
+ * @size_peak: A value to set
+ *
+ * Sets the largest size the list has ever been.
+ *
+ * Since: 43
+ **/
+void
+gs_app_list_set_size_peak (GsAppList *list,
+			   guint size_peak)
+{
+	g_return_if_fail (GS_IS_APP_LIST (list));
+	list->size_peak = size_peak;
+}
+
+static GsApp *
+gs_app_list_lookup_safe (GsAppList *list, const gchar *unique_id)
+{
+	for (guint i = 0; i < list->array->len; i++) {
+		GsApp *app = g_ptr_array_index (list->array, i);
+		if (as_utils_data_id_equal (gs_app_get_unique_id (app), unique_id))
+			return app;
+	}
+	return NULL;
+}
+
+/**
+ * gs_app_list_lookup:
+ * @list: A #GsAppList
+ * @unique_id: A unique_id
+ *
+ * Finds the first matching application in the list using the usual wildcard
+ * rules allowed in unique_ids.
+ *
+ * Returns: (transfer none): a #GsApp, or %NULL if not found
+ *
+ * Since: 3.22
+ **/
+GsApp *
+gs_app_list_lookup (GsAppList *list, const gchar *unique_id)
+{
+	g_autoptr(GMutexLocker) locker = g_mutex_locker_new (&list->mutex);
+	return gs_app_list_lookup_safe (list, unique_id);
+}
+
+/**
+ * gs_app_list_has_flag:
+ * @list: A #GsAppList
+ * @flag: A flag to test, e.g. %GS_APP_LIST_FLAG_IS_TRUNCATED
+ *
+ * Gets if a specific flag is set.
+ *
+ * Returns: %TRUE if the flag is set
+ *
+ * Since: 3.24
+ **/
+gboolean
+gs_app_list_has_flag (GsAppList *list, GsAppListFlags flag)
+{
+	return (list->flags & flag) > 0;
+}
+
+/**
+ * gs_app_list_add_flag:
+ * @list: A #GsAppList
+ * @flag: A flag to test, e.g. %GS_APP_LIST_FLAG_IS_TRUNCATED
+ *
+ * Gets if a specific flag is set.
+ *
+ * Returns: %TRUE if the flag is set
+ *
+ * Since: 3.30
+ **/
+void
+gs_app_list_add_flag (GsAppList *list, GsAppListFlags flag)
+{
+	if (list->flags & flag)
+		return;
+	list->flags |= flag;
+
+	/* turn this on for existing apps */
+	for (guint i = 0; i < list->array->len; i++) {
+		GsApp *app = g_ptr_array_index (list->array, i);
+		gs_app_list_maybe_watch_app (list, app);
+	}
+}
+
+static gboolean
+gs_app_list_check_for_duplicate (GsAppList *list, GsApp *app)
+{
+	GsApp *app_old;
+	const gchar *id;
+
+	/* adding a wildcard */
+	if (gs_app_has_quirk (app, GS_APP_QUIRK_IS_WILDCARD)) {
+		for (guint i = 0; i < list->array->len; i++) {
+			GsApp *app_tmp = g_ptr_array_index (list->array, i);
+			if (!gs_app_has_quirk (app_tmp, GS_APP_QUIRK_IS_WILDCARD))
+				continue;
+			/* not adding exactly the same wildcard */
+			if (g_strcmp0 (gs_app_get_unique_id (app_tmp),
+				       gs_app_get_unique_id (app)) == 0)
+				return FALSE;
+		}
+		return TRUE;
+	}
+
+	for (guint i = 0; i < list->array->len; i++) {
+		GsApp *app_tmp = g_ptr_array_index (list->array, i);
+		if (app_tmp == app)
+			return FALSE;
+	}
+
+	/* does not exist */
+	id = gs_app_get_unique_id (app);
+	if (id == NULL) {
+		/* not much else we can do... */
+		return TRUE;
+	}
+
+	/* existing app is a wildcard */
+	app_old = gs_app_list_lookup_safe (list, id);
+	if (app_old == NULL)
+		return TRUE;
+	if (gs_app_has_quirk (app_old, GS_APP_QUIRK_IS_WILDCARD))
+		return TRUE;
+
+	/* already exists */
+	return FALSE;
+}
+
+typedef enum {
+	GS_APP_LIST_ADD_FLAG_NONE		= 0,
+	GS_APP_LIST_ADD_FLAG_CHECK_FOR_DUPE	= 1 << 0,
+	GS_APP_LIST_ADD_FLAG_LAST
+} GsAppListAddFlag;
+
+static void
+gs_app_list_add_safe (GsAppList *list, GsApp *app, GsAppListAddFlag flag)
+{
+	/* check for duplicate */
+	if ((flag & GS_APP_LIST_ADD_FLAG_CHECK_FOR_DUPE) > 0 &&
+	    !gs_app_list_check_for_duplicate (list, app))
+		return;
+
+	/* just use the ref */
+	gs_app_list_maybe_watch_app (list, app);
+	g_ptr_array_add (list->array, g_object_ref (app));
+
+	/* update the historical max */
+	if (list->array->len > list->size_peak)
+		list->size_peak = list->array->len;
+}
+
+/**
+ * gs_app_list_add:
+ * @list: A #GsAppList
+ * @app: A #GsApp
+ *
+ * If the application does not already exist in the list then it is added,
+ * incrementing the reference count.
+ * If the application already exists then a warning is printed to the console.
+ *
+ * Applications that have the application ID lazy-loaded will always be added
+ * to the list, and to clean these up the plugin loader will also call the
+ * gs_app_list_filter_duplicates() method when all plugins have run.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_list_add (GsAppList *list, GsApp *app)
+{
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP_LIST (list));
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&list->mutex);
+	gs_app_list_add_safe (list, app, GS_APP_LIST_ADD_FLAG_CHECK_FOR_DUPE);
+
+	/* recalculate global state */
+	gs_app_list_invalidate_state (list);
+	gs_app_list_invalidate_progress (list);
+}
+
+/**
+ * gs_app_list_remove:
+ * @list: A #GsAppList
+ * @app: A #GsApp
+ *
+ * Removes an application from the list. If the application does not exist the
+ * request is ignored.
+ *
+ * Returns: %TRUE if the app was removed, %FALSE if it did not exist in the @list
+ * Since: 43
+ **/
+gboolean
+gs_app_list_remove (GsAppList *list, GsApp *app)
+{
+	g_autoptr(GMutexLocker) locker = NULL;
+	gboolean removed;
+
+	g_return_val_if_fail (GS_IS_APP_LIST (list), FALSE);
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+
+	locker = g_mutex_locker_new (&list->mutex);
+	removed = g_ptr_array_remove (list->array, app);
+	if (removed) {
+		gs_app_list_maybe_unwatch_app (list, app);
+
+		/* recalculate global state */
+		gs_app_list_invalidate_state (list);
+		gs_app_list_invalidate_progress (list);
+	}
+
+	return removed;
+}
+
+/**
+ * gs_app_list_add_list:
+ * @list: A #GsAppList
+ * @donor: Another #GsAppList
+ *
+ * Adds all the applications in @donor to @list.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_list_add_list (GsAppList *list, GsAppList *donor)
+{
+	guint i;
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_APP_LIST (list));
+	g_return_if_fail (GS_IS_APP_LIST (donor));
+	g_return_if_fail (list != donor);
+
+	locker = g_mutex_locker_new (&list->mutex);
+
+	/* add each app */
+	for (i = 0; i < donor->array->len; i++) {
+		GsApp *app = gs_app_list_index (donor, i);
+		gs_app_list_add_safe (list, app, GS_APP_LIST_ADD_FLAG_CHECK_FOR_DUPE);
+	}
+
+	/* recalculate global state */
+	gs_app_list_invalidate_state (list);
+	gs_app_list_invalidate_progress (list);
+}
+
+/**
+ * gs_app_list_index:
+ * @list: A #GsAppList
+ * @idx: An index into the list
+ *
+ * Gets an application at a specific position in the list.
+ *
+ * Returns: (transfer none): a #GsApp, or %NULL if invalid
+ *
+ * Since: 3.22
+ **/
+GsApp *
+gs_app_list_index (GsAppList *list, guint idx)
+{
+	return GS_APP (g_ptr_array_index (list->array, idx));
+}
+
+/**
+ * gs_app_list_length:
+ * @list: A #GsAppList
+ *
+ * Gets the length of the application list.
+ *
+ * Returns: Integer
+ *
+ * Since: 3.22
+ **/
+guint
+gs_app_list_length (GsAppList *list)
+{
+	g_return_val_if_fail (GS_IS_APP_LIST (list), 0);
+	return list->array->len;
+}
+
+static void
+gs_app_list_remove_all_safe (GsAppList *list)
+{
+	for (guint i = 0; i < list->array->len; i++) {
+		GsApp *app = g_ptr_array_index (list->array, i);
+		gs_app_list_maybe_unwatch_app (list, app);
+	}
+	g_ptr_array_set_size (list->array, 0);
+	gs_app_list_invalidate_state (list);
+	gs_app_list_invalidate_progress (list);
+}
+
+/**
+ * gs_app_list_remove_all:
+ * @list: A #GsAppList
+ *
+ * Removes all applications from the list.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_list_remove_all (GsAppList *list)
+{
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP_LIST (list));
+	locker = g_mutex_locker_new (&list->mutex);
+	gs_app_list_remove_all_safe (list);
+}
+
+/**
+ * gs_app_list_filter:
+ * @list: A #GsAppList
+ * @func: A #GsAppListFilterFunc
+ * @user_data: the user pointer to pass to @func
+ *
+ * If func() returns TRUE for the GsApp, then the app is kept.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_list_filter (GsAppList *list, GsAppListFilterFunc func, gpointer user_data)
+{
+	guint i;
+	GsApp *app;
+	g_autoptr(GsAppList) old = NULL;
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_APP_LIST (list));
+	g_return_if_fail (func != NULL);
+
+	locker = g_mutex_locker_new (&list->mutex);
+
+	/* deep copy to a temp list and clear the current one */
+	old = gs_app_list_copy (list);
+	gs_app_list_remove_all_safe (list);
+
+	/* see if any of the apps need filtering */
+	for (i = 0; i < old->array->len; i++) {
+		app = gs_app_list_index (old, i);
+		if (func (app, user_data))
+			gs_app_list_add_safe (list, app, GS_APP_LIST_ADD_FLAG_NONE);
+	}
+}
+
+typedef struct {
+	GsAppListSortFunc	 func;
+	gpointer		 user_data;
+} GsAppListSortHelper;
+
+static gint
+gs_app_list_sort_cb (gconstpointer a, gconstpointer b, gpointer user_data)
+{
+	GsApp *app1 = GS_APP (*(GsApp **) a);
+	GsApp *app2 = GS_APP (*(GsApp **) b);
+	const GsAppListSortHelper *helper = (GsAppListSortHelper *) user_data;
+	return helper->func (app1, app2, helper->user_data);
+}
+
+/**
+ * gs_app_list_sort:
+ * @list: A #GsAppList
+ * @func: A #GsAppListSortFunc
+ * @user_data: user data to pass to @func
+ *
+ * Sorts the application list.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_list_sort (GsAppList *list, GsAppListSortFunc func, gpointer user_data)
+{
+	g_autoptr(GMutexLocker) locker = NULL;
+	GsAppListSortHelper helper;
+	g_return_if_fail (GS_IS_APP_LIST (list));
+	locker = g_mutex_locker_new (&list->mutex);
+	helper.func = func;
+	helper.user_data = user_data;
+	g_ptr_array_sort_with_data (list->array, gs_app_list_sort_cb, &helper);
+}
+
+/**
+ * gs_app_list_truncate:
+ * @list: A #GsAppList
+ * @length: the new length
+ *
+ * Truncates the application list. It is an error if @length is larger than the
+ * size of the list.
+ *
+ * Since: 3.24
+ **/
+void
+gs_app_list_truncate (GsAppList *list, guint length)
+{
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_APP_LIST (list));
+	g_return_if_fail (length <= list->array->len);
+
+	/* mark this list as unworthy */
+	list->flags |= GS_APP_LIST_FLAG_IS_TRUNCATED;
+
+	/* everything */
+	if (length == 0) {
+		gs_app_list_remove_all (list);
+		return;
+	}
+
+	/* remove the apps in the positions larger than the length */
+	locker = g_mutex_locker_new (&list->mutex);
+	g_ptr_array_set_size (list->array, length);
+}
+
+/**
+ * gs_app_list_randomize:
+ * @list: A #GsAppList
+ *
+ * Randomize the order of the list, but don't change the order until
+ * the next day.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_list_randomize (GsAppList *list)
+{
+	GRand *rand;
+	g_autoptr(GDateTime) date = NULL;
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_APP_LIST (list));
+
+	locker = g_mutex_locker_new (&list->mutex);
+
+	if (!gs_app_list_length (list))
+		return;
+
+	rand = g_rand_new ();
+	date = g_date_time_new_now_utc ();
+	g_rand_set_seed (rand, (guint32) g_date_time_get_day_of_year (date));
+
+	/* Fisher–Yates shuffle of the array.
+	 * See https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle */
+	for (guint i = gs_app_list_length (list) - 1; i >= 1; i--) {
+		gpointer tmp;
+		guint j = g_rand_int_range (rand, 0, i + 1);
+
+		tmp = list->array->pdata[i];
+		list->array->pdata[i] = list->array->pdata[j];
+		list->array->pdata[j] = tmp;
+	}
+
+	g_rand_free (rand);
+}
+
+static gboolean
+gs_app_list_filter_app_is_better (GsApp *app, GsApp *found, GsAppListFilterFlags flags)
+{
+	/* optional 1st layer sort */
+	if ((flags & GS_APP_LIST_FILTER_FLAG_PREFER_INSTALLED) > 0) {
+		if (gs_app_is_installed (app) && !gs_app_is_installed (found))
+			return TRUE;
+		if (!gs_app_is_installed (app) && gs_app_is_installed (found))
+			return FALSE;
+	}
+
+	/* 2nd layer, priority and bundle kind */
+	if (gs_app_compare_priority (app, found) < 0)
+		return TRUE;
+
+	/* assume is worse */
+	return FALSE;
+}
+
+static GPtrArray *
+gs_app_list_filter_app_get_keys (GsApp *app, GsAppListFilterFlags flags)
+{
+	GPtrArray *keys = g_ptr_array_new_with_free_func (g_free);
+	g_autoptr(GString) key = NULL;
+
+	/* just use the unique ID */
+	if (flags == GS_APP_LIST_FILTER_FLAG_NONE) {
+		if (gs_app_get_unique_id (app) != NULL)
+			g_ptr_array_add (keys, g_strdup (gs_app_get_unique_id (app)));
+		return keys;
+	}
+
+	/* use the ID and any provided items */
+	if (flags & GS_APP_LIST_FILTER_FLAG_KEY_ID_PROVIDES) {
+		GPtrArray *provided = gs_app_get_provided (app);
+		g_ptr_array_add (keys, g_strdup (gs_app_get_id (app)));
+		for (guint i = 0; i < provided->len; i++) {
+			AsProvided *prov = g_ptr_array_index (provided, i);
+			GPtrArray *items;
+			if (as_provided_get_kind (prov) != AS_PROVIDED_KIND_ID)
+				continue;
+			items = as_provided_get_items (prov);
+			for (guint j = 0; j < items->len; j++)
+				g_ptr_array_add (keys, g_strdup (g_ptr_array_index (items, j)));
+		}
+		return keys;
+	}
+
+	/* specific compound type */
+	key = g_string_new (NULL);
+	if (flags & GS_APP_LIST_FILTER_FLAG_KEY_ID) {
+		const gchar *tmp = gs_app_get_id (app);
+		if (tmp != NULL)
+			g_string_append (key, gs_app_get_id (app));
+	}
+	if (flags & GS_APP_LIST_FILTER_FLAG_KEY_SOURCE) {
+		const gchar *tmp = gs_app_get_source_default (app);
+		if (tmp != NULL)
+			g_string_append_printf (key, ":%s", tmp);
+	}
+	if (flags & GS_APP_LIST_FILTER_FLAG_KEY_VERSION) {
+		const gchar *tmp = gs_app_get_version (app);
+		if (tmp != NULL)
+			g_string_append_printf (key, ":%s", tmp);
+	}
+	if (key->len == 0)
+		return keys;
+	g_ptr_array_add (keys, g_string_free (g_steal_pointer (&key), FALSE));
+	return keys;
+}
+
+/**
+ * gs_app_list_filter_duplicates:
+ * @list: A #GsAppList
+ * @flags: a #GsAppListFilterFlags, e.g. GS_APP_LIST_FILTER_KEY_ID
+ *
+ * Filter any duplicate applications from the list.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_list_filter_duplicates (GsAppList *list, GsAppListFilterFlags flags)
+{
+	g_autoptr(GHashTable) hash = NULL;
+	g_autoptr(GHashTable) kept_apps = NULL;
+	g_autoptr(GsAppList) old = NULL;
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_APP_LIST (list));
+
+	locker = g_mutex_locker_new (&list->mutex);
+
+	/* a hash table to hold apps with unique app ids */
+	hash = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
+	/* a hash table containing apps we want to keep */
+	kept_apps = g_hash_table_new (g_direct_hash, g_direct_equal);
+
+	for (guint i = 0; i < list->array->len; i++) {
+		GsApp *app = gs_app_list_index (list, i);
+		GsApp *found = NULL;
+		g_autoptr(GPtrArray) keys = NULL;
+
+		/* get all the keys used to identify this app */
+		keys = gs_app_list_filter_app_get_keys (app, flags);
+		for (guint j = 0; j < keys->len; j++) {
+			const gchar *key = g_ptr_array_index (keys, j);
+			found = g_hash_table_lookup (hash, key);
+			if (found != NULL)
+				break;
+		}
+
+		/* new app */
+		if (found == NULL) {
+			for (guint j = 0; j < keys->len; j++) {
+				const gchar *key = g_ptr_array_index (keys, j);
+				g_hash_table_insert (hash, g_strdup (key), app);
+			}
+			g_hash_table_add (kept_apps, app);
+			continue;
+		}
+
+		/* better? */
+		if (flags != GS_APP_LIST_FILTER_FLAG_NONE) {
+			if (gs_app_list_filter_app_is_better (app, found, flags)) {
+				for (guint j = 0; j < keys->len; j++) {
+					const gchar *key = g_ptr_array_index (keys, j);
+					g_hash_table_insert (hash, g_strdup (key), app);
+				}
+				g_hash_table_remove (kept_apps, found);
+				g_hash_table_add (kept_apps, app);
+				continue;
+			}
+			continue;
+		}
+		continue;
+	}
+
+	/* deep copy to a temp list and clear the current one */
+	old = gs_app_list_copy (list);
+	gs_app_list_remove_all_safe (list);
+
+	/* add back the apps we want to keep */
+	for (guint i = 0; i < old->array->len; i++) {
+		GsApp *app = gs_app_list_index (old, i);
+		if (g_hash_table_contains (kept_apps, app)) {
+			gs_app_list_add_safe (list, app, GS_APP_LIST_ADD_FLAG_NONE);
+			/* In case the same instance is in the 'list' multiple times */
+			g_hash_table_remove (kept_apps, app);
+		}
+	}
+}
+
+/**
+ * gs_app_list_copy:
+ * @list: A #GsAppList
+ *
+ * Returns a deep copy of the application list.
+ *
+ * Returns: A newly allocated #GsAppList
+ *
+ * Since: 3.22
+ **/
+GsAppList *
+gs_app_list_copy (GsAppList *list)
+{
+	GsAppList *new;
+	guint i;
+
+	g_return_val_if_fail (GS_IS_APP_LIST (list), NULL);
+
+	new = gs_app_list_new ();
+	for (i = 0; i < gs_app_list_length (list); i++) {
+		GsApp *app = gs_app_list_index (list, i);
+		gs_app_list_add_safe (new, app, GS_APP_LIST_ADD_FLAG_NONE);
+	}
+	return new;
+}
+
+static void
+gs_app_list_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
+{
+	GsAppList *self = GS_APP_LIST (object);
+	switch (prop_id) {
+	case PROP_STATE:
+		g_value_set_enum (value, self->state);
+		break;
+	case PROP_PROGRESS:
+		g_value_set_uint (value, self->progress);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_app_list_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
+{
+	switch (prop_id) {
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_app_list_finalize (GObject *object)
+{
+	GsAppList *list = GS_APP_LIST (object);
+	g_ptr_array_unref (list->array);
+	g_mutex_clear (&list->mutex);
+	G_OBJECT_CLASS (gs_app_list_parent_class)->finalize (object);
+}
+
+static void
+gs_app_list_class_init (GsAppListClass *klass)
+{
+	GParamSpec *pspec;
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+	object_class->get_property = gs_app_list_get_property;
+	object_class->set_property = gs_app_list_set_property;
+	object_class->finalize = gs_app_list_finalize;
+
+	/**
+	 * GsAppList:state:
+	 */
+	pspec = g_param_spec_enum ("state", NULL, NULL,
+				   GS_TYPE_APP_STATE,
+				   GS_APP_STATE_UNKNOWN,
+				   G_PARAM_READABLE);
+	g_object_class_install_property (object_class, PROP_STATE, pspec);
+
+	/**
+	 * GsAppList:progress:
+	 *
+	 * A percentage (0–100, inclusive) indicating the progress through the
+	 * current task on this app list. The value may otherwise be
+	 * %GS_APP_PROGRESS_UNKNOWN if the progress is unknown or has a wide
+	 * confidence interval on any app, or if the app list is empty.
+	 */
+	pspec = g_param_spec_uint ("progress", NULL, NULL,
+				   0, GS_APP_PROGRESS_UNKNOWN, GS_APP_PROGRESS_UNKNOWN,
+				   G_PARAM_READABLE);
+	g_object_class_install_property (object_class, PROP_PROGRESS, pspec);
+
+	/**
+	 * GsAppList:app-state-changed:
+	 * @app: a #GsApp
+	 *
+	 * Emitted when any of the internal #GsApp instances changes its state.
+	 *
+	 * Since: 3.40
+	 */
+	signals [SIGNAL_APP_STATE_CHANGED] =
+		g_signal_new ("app-state-changed",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      0, NULL, NULL, g_cclosure_marshal_generic,
+			      G_TYPE_NONE, 1, GS_TYPE_APP);
+}
+
+static void
+gs_app_list_init (GsAppList *list)
+{
+	g_mutex_init (&list->mutex);
+	list->array = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);
+	list->custom_progress = GS_APP_PROGRESS_UNKNOWN;
+}
+
+/**
+ * gs_app_list_new:
+ *
+ * Creates a new list.
+ *
+ * Returns: A newly allocated #GsAppList
+ *
+ * Since: 3.22
+ **/
+GsAppList *
+gs_app_list_new (void)
+{
+	GsAppList *list;
+	list = g_object_new (GS_TYPE_APP_LIST, NULL);
+	return GS_APP_LIST (list);
+}
diff --git a/lib/gs-app-list.h b/lib/gs-app-list.h
new file mode 100644
index 0000000..adf85f7
--- /dev/null
+++ b/lib/gs-app-list.h
@@ -0,0 +1,89 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2012-2016 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib-object.h>
+
+#include "gs-app.h"
+
+G_BEGIN_DECLS
+
+/**
+ * GsAppListFilterFlags:
+ * @GS_APP_LIST_FILTER_FLAG_NONE:		No flags set
+ * @GS_APP_LIST_FILTER_FLAG_KEY_ID:		Filter by ID
+ * @GS_APP_LIST_FILTER_FLAG_KEY_SOURCE:		Filter by default source
+ * @GS_APP_LIST_FILTER_FLAG_KEY_VERSION:	Filter by version
+ * @GS_APP_LIST_FILTER_FLAG_PREFER_INSTALLED:	Prefer installed applications
+ * @GS_APP_LIST_FILTER_FLAG_KEY_ID_PROVIDES:	Filter using the provides ID
+ *
+ * Flags to use when filtering. The priority of each #GsApp is used to choose
+ * which application object to keep.
+ *
+ * Since: 40
+ **/
+typedef enum {
+	GS_APP_LIST_FILTER_FLAG_NONE		= 0,
+	GS_APP_LIST_FILTER_FLAG_KEY_ID		= 1 << 0,
+	GS_APP_LIST_FILTER_FLAG_KEY_SOURCE	= 1 << 1,
+	GS_APP_LIST_FILTER_FLAG_KEY_VERSION	= 1 << 2,
+	GS_APP_LIST_FILTER_FLAG_PREFER_INSTALLED= 1 << 3,
+	GS_APP_LIST_FILTER_FLAG_KEY_ID_PROVIDES	= 1 << 4,
+	GS_APP_LIST_FILTER_FLAG_LAST,  /*< skip >*/
+	GS_APP_LIST_FILTER_FLAG_MASK		= G_MAXUINT64
+} GsAppListFilterFlags;
+
+/* All the properties which use #GsAppListFilterFlags are guint64s. */
+G_STATIC_ASSERT (sizeof (GsAppListFilterFlags) == sizeof (guint64));
+
+#define GS_TYPE_APP_LIST (gs_app_list_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsAppList, gs_app_list, GS, APP_LIST, GObject)
+
+/**
+ * GsAppListSortFunc:
+ * @app1:
+ * @app2:
+ * @user_data: user data passed into the sort function
+ *
+ * A version of #GCompareFunc which is specific to #GsApps.
+ *
+ * Returns: zero if @app1 and @app2 are equal, a negative value if @app1 comes
+ *     before @app2, or a positive value if @app1 comes after @app2
+ * Since: 41
+ */
+typedef gint	 (*GsAppListSortFunc)		(GsApp		*app1,
+						 GsApp		*app2,
+						 gpointer	 user_data);
+typedef gboolean (*GsAppListFilterFunc)		(GsApp		*app,
+						 gpointer	 user_data);
+
+GsAppList	*gs_app_list_new		(void);
+GsAppList	*gs_app_list_copy		(GsAppList	*list);
+void		 gs_app_list_add		(GsAppList	*list,
+						 GsApp		*app);
+void		 gs_app_list_add_list		(GsAppList	*list,
+						 GsAppList	*donor);
+gboolean	 gs_app_list_remove		(GsAppList	*list,
+						 GsApp		*app);
+GsApp		*gs_app_list_index		(GsAppList	*list,
+						 guint		 idx);
+GsApp		*gs_app_list_lookup		(GsAppList	*list,
+						 const gchar	*unique_id);
+guint		 gs_app_list_length		(GsAppList	*list);
+void		 gs_app_list_sort		(GsAppList	*list,
+						 GsAppListSortFunc func,
+						 gpointer	 user_data);
+void		 gs_app_list_filter		(GsAppList	*list,
+						 GsAppListFilterFunc func,
+						 gpointer	 user_data);
+void		 gs_app_list_override_progress	(GsAppList	*list,
+						 guint		 progress);
+
+G_END_DECLS
diff --git a/lib/gs-app-permissions.c b/lib/gs-app-permissions.c
new file mode 100644
index 0000000..bbae07c
--- /dev/null
+++ b/lib/gs-app-permissions.c
@@ -0,0 +1,430 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2022 Red Hat <www.redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-app-permissions
+ * @short_description: A representation of the permissions requested by an app
+ *
+ * #GsAppPermissions is an object to represent the permissions requested by an app.
+ *
+ * While some common permissions are handled with the #GsAppPermissionsFlags,
+ * the object allows more detailed permissions to be represented, such as
+ * specific file system path access.
+ *
+ * Since: 43
+ */
+
+#include "config.h"
+
+#include <stdlib.h>
+
+#include <glib.h>
+#include <glib-object.h>
+
+#include "gs-app-permissions.h"
+
+#define DOES_NOT_CONTAIN ((guint) ~0)
+
+struct _GsAppPermissions
+{
+	GObject parent;
+
+	gboolean is_sealed;
+	GsAppPermissionsFlags flags;
+	GPtrArray *filesystem_read; /* (owner) (nullable) (element-type utf-8) */
+	GPtrArray *filesystem_full; /* (owner) (nullable) (element-type utf-8) */
+};
+
+G_DEFINE_TYPE (GsAppPermissions, gs_app_permissions, G_TYPE_OBJECT)
+
+static gint
+cmp_filename_qsort (gconstpointer item1,
+		    gconstpointer item2)
+{
+	const gchar * const *pitem1 = item1;
+	const gchar * const *pitem2 = item2;
+	return strcmp (*pitem1, *pitem2);
+}
+
+static gint
+cmp_filename_bsearch (gconstpointer item1,
+		      gconstpointer item2)
+{
+	return strcmp (item1, item2);
+}
+
+static void
+gs_app_permissions_finalize (GObject *object)
+{
+	GsAppPermissions *self = GS_APP_PERMISSIONS (object);
+
+	g_clear_pointer (&self->filesystem_read, g_ptr_array_unref);
+	g_clear_pointer (&self->filesystem_full, g_ptr_array_unref);
+
+	G_OBJECT_CLASS (gs_app_permissions_parent_class)->finalize (object);
+}
+
+static void
+gs_app_permissions_class_init (GsAppPermissionsClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+	object_class->finalize = gs_app_permissions_finalize;
+}
+
+static void
+gs_app_permissions_init (GsAppPermissions *self)
+{
+}
+
+/**
+ * gs_app_permissions_new:
+ *
+ * Create a new #GsAppPermissions containing the app permissions.
+ *
+ * Returns: (transfer full): a new #GsAppPermissions
+ * Since: 43
+ */
+GsAppPermissions *
+gs_app_permissions_new (void)
+{
+	return g_object_new (GS_TYPE_APP_PERMISSIONS, NULL);
+}
+
+/**
+ * gs_app_permissions_seal:
+ * @self: a #GsAppPermissions
+ *
+ * Seal the @self. After being called, no modifications can be
+ * done on the @self.
+ *
+ * Since: 43
+ **/
+void
+gs_app_permissions_seal (GsAppPermissions *self)
+{
+	g_return_if_fail (GS_IS_APP_PERMISSIONS (self));
+
+	if (self->is_sealed)
+		return;
+
+	self->is_sealed = TRUE;
+
+	/* Sort the arrays, which will help with searching */
+	if (self->filesystem_read)
+		qsort (self->filesystem_read->pdata, self->filesystem_read->len, sizeof (gpointer), cmp_filename_qsort);
+
+	if (self->filesystem_full)
+		qsort (self->filesystem_full->pdata, self->filesystem_full->len, sizeof (gpointer), cmp_filename_qsort);
+}
+
+/**
+ * gs_app_permissions_is_sealed:
+ * @self: a #GsAppPermissions
+ *
+ * Checks whether the @self had been sealed. Once the @self is sealed,
+ * no modifications can be made to it.
+ *
+ * Returns: whether the @self had been sealed
+ *
+ * Since: 43
+ **/
+gboolean
+gs_app_permissions_is_sealed (GsAppPermissions *self)
+{
+	g_return_val_if_fail (GS_IS_APP_PERMISSIONS (self), TRUE);
+
+	return self->is_sealed;
+}
+
+/**
+ * gs_app_permissions_set_flags:
+ * @self: a #GsAppPermissions
+ * @flags: a #GsAppPermissionsFlags to set
+ *
+ * Set the permission flags, overwriting any previously set flags.
+ * Compare to gs_app_permissions_add_flag() and
+ * gs_app_permissions_remove_flag().
+ *
+ * Since: 43
+ */
+void
+gs_app_permissions_set_flags (GsAppPermissions *self,
+			      GsAppPermissionsFlags flags)
+{
+	g_return_if_fail (GS_IS_APP_PERMISSIONS (self));
+
+	g_assert (!self->is_sealed);
+
+	self->flags = flags;
+}
+
+/**
+ * gs_app_permissions_get_flags:
+ * @self: a #GsAppPermissions
+ *
+ * Get the permission flags.
+ *
+ * Returns: the permission flags
+ * Since: 43
+ */
+GsAppPermissionsFlags
+gs_app_permissions_get_flags (GsAppPermissions *self)
+{
+	g_return_val_if_fail (GS_IS_APP_PERMISSIONS (self), GS_APP_PERMISSIONS_FLAGS_UNKNOWN);
+
+	return self->flags;
+}
+
+/**
+ * gs_app_permissions_add_flag:
+ * @self: a #GsAppPermissions
+ * @flags: a #GsAppPermissionsFlags to add
+ *
+ * Add the @flags into the already set flags. The @flags cannot contain
+ * #GS_APP_PERMISSIONS_FLAGS_NONE, neither cannot be #GS_APP_PERMISSIONS_FLAGS_UNKNOWN.
+ * To set these two use gs_app_permissions_set_flags() instead.
+ *
+ * In case the current flags contain #GS_APP_PERMISSIONS_FLAGS_NONE, it's
+ * automatically unset.
+ *
+ * Since: 43
+ */
+void
+gs_app_permissions_add_flag (GsAppPermissions *self,
+			     GsAppPermissionsFlags flags)
+{
+	g_return_if_fail (GS_IS_APP_PERMISSIONS (self));
+	g_return_if_fail (flags != GS_APP_PERMISSIONS_FLAGS_UNKNOWN);
+	g_return_if_fail ((flags & GS_APP_PERMISSIONS_FLAGS_NONE) == 0);
+
+	g_assert (!self->is_sealed);
+
+	self->flags = (self->flags & (~GS_APP_PERMISSIONS_FLAGS_NONE)) | flags;
+}
+
+/**
+ * gs_app_permissions_remove_flag:
+ * @self: a #GsAppPermissions
+ * @flags: a #GsAppPermissionsFlags to remove
+ *
+ * Remove the @flags from the already set flags. The @flags cannot contain
+ * #GS_APP_PERMISSIONS_FLAGS_NONE, neither cannot be #GS_APP_PERMISSIONS_FLAGS_UNKNOWN.
+ * To set these two use gs_app_permissions_set_flags() instead.
+ *
+ * In case the result of the removal would lead to no flag set the #GS_APP_PERMISSIONS_FLAGS_NONE
+ * is set automatically.
+ *
+ * Since: 43
+ */
+void
+gs_app_permissions_remove_flag (GsAppPermissions *self,
+				GsAppPermissionsFlags flags)
+{
+	g_return_if_fail (GS_IS_APP_PERMISSIONS (self));
+	g_return_if_fail (flags != GS_APP_PERMISSIONS_FLAGS_UNKNOWN);
+	g_return_if_fail ((flags & GS_APP_PERMISSIONS_FLAGS_NONE) == 0);
+
+	g_assert (!self->is_sealed);
+
+	self->flags = (self->flags & (~flags));
+
+	if (!self->flags)
+		self->flags = GS_APP_PERMISSIONS_FLAGS_NONE;
+}
+
+static guint
+app_permissions_get_array_index (GPtrArray *array,
+				 const gchar *filename)
+{
+	g_return_val_if_fail (filename != NULL, DOES_NOT_CONTAIN);
+
+	if (array == NULL)
+		return DOES_NOT_CONTAIN;
+
+	for (guint i = 0; i < array->len; i++) {
+		const gchar *item = g_ptr_array_index (array, i);
+		if (g_strcmp0 (item, filename) == 0)
+			return 0;
+	}
+
+	return DOES_NOT_CONTAIN;
+}
+
+/**
+ * gs_app_permissions_add_filesystem_read:
+ * @self: a #GsAppPermissions
+ * @filename: a filename to access
+ *
+ * Add @filename as a file to access for read. The @filename
+ * can be either a path or a localized pretty name of it, like "Documents".
+ * The addition is ignored in case the same @filename is part of
+ * the read or full access file names.
+ *
+ * Since: 43
+ */
+void
+gs_app_permissions_add_filesystem_read (GsAppPermissions *self,
+					const gchar *filename)
+{
+	g_return_if_fail (GS_IS_APP_PERMISSIONS (self));
+	g_return_if_fail (filename != NULL);
+
+	g_assert (!self->is_sealed);
+
+	/* Already known */
+	if (app_permissions_get_array_index (self->filesystem_read, filename) != DOES_NOT_CONTAIN ||
+	    app_permissions_get_array_index (self->filesystem_full, filename) != DOES_NOT_CONTAIN)
+		return;
+
+	if (self->filesystem_read == NULL)
+		self->filesystem_read = g_ptr_array_new_with_free_func (g_free);
+
+	g_ptr_array_add (self->filesystem_read, g_strdup (filename));
+}
+
+/**
+ * gs_app_permissions_get_filesystem_read:
+ * @self: a #GsAppPermissions
+ *
+ * Get the list of filesystem file names requested for read access using
+ * gs_app_permissions_add_filesystem_read().
+ * The array is owned by the @self and should not be modified by any way.
+ * It can be %NULL, when no file access was set.
+ *
+ * Returns: (nullable) (transfer none) (element-type utf-8): an array of
+ *    file names requesting read access or %NULL, when none was set.
+ *
+ * Since: 43
+ */
+const GPtrArray *
+gs_app_permissions_get_filesystem_read (GsAppPermissions *self)
+{
+	g_return_val_if_fail (GS_IS_APP_PERMISSIONS (self), NULL);
+
+	return self->filesystem_read;
+}
+
+static gboolean
+array_contains_filename (GPtrArray *array,
+			 const gchar *filename)
+{
+	if (array == NULL)
+		return FALSE;
+
+	return bsearch (filename, array->pdata, array->len, sizeof (gpointer), cmp_filename_bsearch) != NULL;
+}
+
+/**
+ * gs_app_permissions_contains_filesystem_read:
+ * @self: a #GsAppPermissions
+ * @filename: a file name to search for
+ *
+ * Checks whether the @filename is included in the filesystem read permissions.
+ * This can be called only after the @self is sealed.
+ *
+ * Returns: whether the @filename is part of the filesystem read permissions
+ *
+ * Since: 43
+ **/
+gboolean
+gs_app_permissions_contains_filesystem_read (GsAppPermissions *self,
+					     const gchar *filename)
+{
+	g_return_val_if_fail (GS_IS_APP_PERMISSIONS (self), FALSE);
+	g_return_val_if_fail (filename != NULL, FALSE);
+	g_return_val_if_fail (self->is_sealed, FALSE);
+
+	return array_contains_filename (self->filesystem_read, filename);
+}
+
+/**
+ * gs_app_permissions_add_filesystem_full:
+ * @self: a #GsAppPermissions
+ * @filename: a filename to access
+ *
+ * Add @filename as a file to access for read and write. The @filename
+ * can be either a path or a localized pretty name of it, like "Documents".
+ * The addition is ignored in case the same @filename is include in the list
+ * already. The @filename is removed from the read list, if it's part of it.
+ *
+ * Since: 43
+ */
+void
+gs_app_permissions_add_filesystem_full (GsAppPermissions *self,
+					const gchar *filename)
+{
+	guint read_index;
+
+	g_return_if_fail (GS_IS_APP_PERMISSIONS (self));
+	g_return_if_fail (filename != NULL);
+
+	g_assert (!self->is_sealed);
+
+	/* Already known */
+	if (app_permissions_get_array_index (self->filesystem_full, filename) != DOES_NOT_CONTAIN)
+		return;
+
+	if (self->filesystem_full == NULL)
+		self->filesystem_full = g_ptr_array_new_with_free_func (g_free);
+
+	g_ptr_array_add (self->filesystem_full, g_strdup (filename));
+
+	/* Remove from the read list and free the read list if becomes empty */
+	read_index = app_permissions_get_array_index (self->filesystem_read, filename);
+	if (read_index != DOES_NOT_CONTAIN) {
+		g_ptr_array_remove_index (self->filesystem_read, read_index);
+		if (self->filesystem_read->len == 0)
+			g_clear_pointer (&self->filesystem_read, g_ptr_array_unref);
+	}
+}
+
+/**
+ * gs_app_permissions_get_filesystem_full:
+ * @self: a #GsAppPermissions
+ *
+ * Get the list of filesystem file names requested for read and write access using
+ * gs_app_permissions_add_filesystem_full().
+ * The array is owned by the @self and should not be modified by any way.
+ * It can be %NULL, when no file access was set.
+ *
+ * Returns: (nullable) (transfer none) (element-type utf-8): an array of
+ *    file names requesting read and write access or %NULL, when none was set.
+ *
+ * Since: 43
+ */
+const GPtrArray *
+gs_app_permissions_get_filesystem_full (GsAppPermissions *self)
+{
+	g_return_val_if_fail (GS_IS_APP_PERMISSIONS (self), NULL);
+
+	return self->filesystem_full;
+}
+
+/**
+ * gs_app_permissions_contains_filesystem_full:
+ * @self: a #GsAppPermissions
+ * @filename: a file name to search for
+ *
+ * Checks whether the @filename is included in the filesystem full permissions.
+ * This can be called only after the @self is sealed.
+ *
+ * Returns: whether the @filename is part of the filesystem full permissions
+ *
+ * Since: 43
+ **/
+gboolean
+gs_app_permissions_contains_filesystem_full (GsAppPermissions *self,
+					     const gchar *filename)
+{
+	g_return_val_if_fail (GS_IS_APP_PERMISSIONS (self), FALSE);
+	g_return_val_if_fail (filename != NULL, FALSE);
+	g_return_val_if_fail (self->is_sealed, FALSE);
+
+	return array_contains_filename (self->filesystem_full, filename);
+}
diff --git a/lib/gs-app-permissions.h b/lib/gs-app-permissions.h
new file mode 100644
index 0000000..96c482b
--- /dev/null
+++ b/lib/gs-app-permissions.h
@@ -0,0 +1,74 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2022 Red Hat <www.redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <glib-object.h>
+
+G_BEGIN_DECLS
+
+typedef enum {
+	GS_APP_PERMISSIONS_FLAGS_UNKNOWN 		= 0,
+	GS_APP_PERMISSIONS_FLAGS_NONE			= 1 << 0,
+	GS_APP_PERMISSIONS_FLAGS_NETWORK 		= 1 << 1,
+	GS_APP_PERMISSIONS_FLAGS_SYSTEM_BUS   		= 1 << 2,
+	GS_APP_PERMISSIONS_FLAGS_SESSION_BUS		= 1 << 3,
+	GS_APP_PERMISSIONS_FLAGS_DEVICES 		= 1 << 4,
+	GS_APP_PERMISSIONS_FLAGS_HOME_FULL 		= 1 << 5,
+	GS_APP_PERMISSIONS_FLAGS_HOME_READ		= 1 << 6,
+	GS_APP_PERMISSIONS_FLAGS_FILESYSTEM_FULL	= 1 << 7,
+	GS_APP_PERMISSIONS_FLAGS_FILESYSTEM_READ	= 1 << 8,
+	GS_APP_PERMISSIONS_FLAGS_DOWNLOADS_FULL 	= 1 << 9,
+	GS_APP_PERMISSIONS_FLAGS_DOWNLOADS_READ		= 1 << 10,
+	GS_APP_PERMISSIONS_FLAGS_SETTINGS		= 1 << 11,
+	GS_APP_PERMISSIONS_FLAGS_X11			= 1 << 12,
+	GS_APP_PERMISSIONS_FLAGS_ESCAPE_SANDBOX		= 1 << 13,
+	GS_APP_PERMISSIONS_FLAGS_FILESYSTEM_OTHER	= 1 << 14,
+	GS_APP_PERMISSIONS_FLAGS_LAST  /*< skip >*/
+} GsAppPermissionsFlags;
+
+#define LIMITED_PERMISSIONS (GS_APP_PERMISSIONS_FLAGS_SETTINGS | \
+			GS_APP_PERMISSIONS_FLAGS_NETWORK | \
+			GS_APP_PERMISSIONS_FLAGS_DOWNLOADS_READ | \
+			GS_APP_PERMISSIONS_FLAGS_DOWNLOADS_FULL)
+#define MEDIUM_PERMISSIONS (LIMITED_PERMISSIONS | \
+			GS_APP_PERMISSIONS_FLAGS_X11)
+
+#define GS_TYPE_APP_PERMISSIONS (gs_app_permissions_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsAppPermissions, gs_app_permissions, GS, APP_PERMISSIONS, GObject)
+
+GsAppPermissions	*gs_app_permissions_new		(void);
+void			 gs_app_permissions_seal	(GsAppPermissions	*self);
+gboolean		 gs_app_permissions_is_sealed	(GsAppPermissions	*self);
+void			 gs_app_permissions_set_flags	(GsAppPermissions	*self,
+							 GsAppPermissionsFlags	 flags);
+GsAppPermissionsFlags	 gs_app_permissions_get_flags	(GsAppPermissions	*self);
+void			 gs_app_permissions_add_flag	(GsAppPermissions	*self,
+							 GsAppPermissionsFlags	 flags);
+void			 gs_app_permissions_remove_flag	(GsAppPermissions	*self,
+							 GsAppPermissionsFlags	 flags);
+void			 gs_app_permissions_add_filesystem_read
+							(GsAppPermissions	*self,
+							 const gchar		*filename);
+const GPtrArray		*gs_app_permissions_get_filesystem_read
+							(GsAppPermissions	*self);
+gboolean		 gs_app_permissions_contains_filesystem_read
+							(GsAppPermissions *self,
+							 const gchar *filename);
+void			 gs_app_permissions_add_filesystem_full
+							(GsAppPermissions	*self,
+							 const gchar		*filename);
+const GPtrArray		*gs_app_permissions_get_filesystem_full
+							(GsAppPermissions	*self);
+gboolean		 gs_app_permissions_contains_filesystem_full
+							(GsAppPermissions *self,
+							 const gchar *filename);
+
+G_END_DECLS
diff --git a/lib/gs-app-private.h b/lib/gs-app-private.h
new file mode 100644
index 0000000..1163bf3
--- /dev/null
+++ b/lib/gs-app-private.h
@@ -0,0 +1,30 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2016 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include "gs-app.h"
+#include "gs-plugin-types.h"
+
+G_BEGIN_DECLS
+
+void		 gs_app_set_priority		(GsApp		*app,
+						 guint		 priority);
+guint		 gs_app_get_priority		(GsApp		*app);
+void		 gs_app_set_unique_id		(GsApp		*app,
+						 const gchar	*unique_id);
+void		 gs_app_remove_addon		(GsApp		*app,
+						 GsApp		*addon);
+GCancellable	*gs_app_get_cancellable		(GsApp		*app);
+GsPluginAction	 gs_app_get_pending_action	(GsApp		*app);
+void		 gs_app_set_pending_action	(GsApp		*app,
+						 GsPluginAction	 action);
+gint		 gs_app_compare_priority	(GsApp		*app1,
+						 GsApp		*app2);
+
+G_END_DECLS
diff --git a/lib/gs-app-query.c b/lib/gs-app-query.c
new file mode 100644
index 0000000..cd2fc93
--- /dev/null
+++ b/lib/gs-app-query.c
@@ -0,0 +1,1173 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2022 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-app-query
+ * @short_description: Immutable representation of a query for apps
+ *
+ * #GsAppQuery is an object to represent a query for apps.
+ *
+ * It will typically be used with #GsPluginJobListApps, which searches for
+ * matching apps, but it may have multiple consumers. #GsAppQuery only
+ * represents the query and does not provide an implementation for executing
+ * that query.
+ *
+ * It is immutable after construction, and hence threadsafe. It may be extended
+ * in future by adding more query properties. The existing query properties are
+ * conjunctive: results should only be returned which match *all* properties
+ * which are set, not _any_ properties which are set.
+ *
+ * The set of apps returned for the query can be controlled with the
+ * #GsAppQuery:refine-flags,
+ * #GsAppQuery:max-results and
+ * #GsAppQuery:dedupe-flags properties. If `refine-flags` is
+ * set, all results must be refined using the given set of refine flags (see
+ * #GsPluginJobRefine). `max-results` and `dedupe-flags` are used to limit the
+ * set of results.
+ *
+ * Results must always be processed in this order:
+ *  - Filtering using #GsAppQuery:filter-func (and any other custom filter
+ *    functions the query executor provides).
+ *  - Deduplication using #GsAppQuery:dedupe-flags.
+ *  - Sorting using #GsAppQuery:sort-func.
+ *  - Truncating result list length to #GsAppQuery:max-results.
+ *
+ * Since: 43
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <glib-object.h>
+
+#include "gs-app.h"
+#include "gs-app-list.h"
+#include "gs-app-query.h"
+#include "gs-enums.h"
+#include "gs-plugin-types.h"
+#include "gs-utils.h"
+
+struct _GsAppQuery
+{
+	GObject parent;
+
+	GsPluginRefineFlags refine_flags;
+	guint max_results;
+	GsAppListFilterFlags dedupe_flags;
+
+	GsAppListSortFunc sort_func;
+	gpointer sort_user_data;
+	GDestroyNotify sort_user_data_notify;
+
+	GsAppListFilterFunc filter_func;
+	gpointer filter_user_data;
+	GDestroyNotify filter_user_data_notify;
+
+	/* This is guaranteed to either be %NULL, or a non-empty array */
+	gchar **provides_files;  /* (owned) (nullable) (array zero-terminated=1) */
+	GDateTime *released_since;  /* (owned) (nullable) */
+	GsAppQueryTristate is_curated;
+	GsAppQueryTristate is_featured;
+	GsCategory *category;  /* (nullable) (owned) */
+	GsAppQueryTristate is_installed;
+
+	/* This is guaranteed to either be %NULL, or a non-empty array */
+	gchar **deployment_featured;  /* (owned) (nullable) (array zero-terminated=1) */
+	/* This is guaranteed to either be %NULL, or a non-empty array */
+	gchar **developers;  /* (owned) (nullable) (array zero-terminated=1) */
+
+	gchar **keywords;  /* (owned) (nullable) (array zero-terminated=1) */
+	GsApp *alternate_of;  /* (nullable) (owned) */
+	gchar *provides_tag;  /* (owned) (nullable) */
+	GsAppQueryProvidesType provides_type;
+};
+
+G_DEFINE_TYPE (GsAppQuery, gs_app_query, G_TYPE_OBJECT)
+
+typedef enum {
+	PROP_REFINE_FLAGS = 1,
+	PROP_MAX_RESULTS,
+	PROP_DEDUPE_FLAGS,
+	PROP_SORT_FUNC,
+	PROP_SORT_USER_DATA,
+	PROP_SORT_USER_DATA_NOTIFY,
+	PROP_FILTER_FUNC,
+	PROP_FILTER_USER_DATA,
+	PROP_FILTER_USER_DATA_NOTIFY,
+	PROP_DEPLOYMENT_FEATURED,
+	PROP_DEVELOPERS,
+	PROP_PROVIDES_FILES,
+	PROP_RELEASED_SINCE,
+	PROP_IS_CURATED,
+	PROP_IS_FEATURED,
+	PROP_CATEGORY,
+	PROP_IS_INSTALLED,
+	PROP_KEYWORDS,
+	PROP_ALTERNATE_OF,
+	PROP_PROVIDES_TAG,
+	PROP_PROVIDES_TYPE,
+} GsAppQueryProperty;
+
+static GParamSpec *props[PROP_PROVIDES_TYPE + 1] = { NULL, };
+
+static void
+gs_app_query_constructed (GObject *object)
+{
+	GsAppQuery *self = GS_APP_QUERY (object);
+
+	G_OBJECT_CLASS (gs_app_query_parent_class)->constructed (object);
+
+	g_assert ((self->provides_tag != NULL) == (self->provides_type != GS_APP_QUERY_PROVIDES_UNKNOWN));
+}
+
+static void
+gs_app_query_get_property (GObject    *object,
+                           guint       prop_id,
+                           GValue     *value,
+                           GParamSpec *pspec)
+{
+	GsAppQuery *self = GS_APP_QUERY (object);
+
+	switch ((GsAppQueryProperty) prop_id) {
+	case PROP_REFINE_FLAGS:
+		g_value_set_flags (value, self->refine_flags);
+		break;
+	case PROP_MAX_RESULTS:
+		g_value_set_uint (value, self->max_results);
+		break;
+	case PROP_DEDUPE_FLAGS:
+		g_value_set_flags (value, self->dedupe_flags);
+		break;
+	case PROP_SORT_FUNC:
+		g_value_set_pointer (value, self->sort_func);
+		break;
+	case PROP_SORT_USER_DATA:
+		g_value_set_pointer (value, self->sort_user_data);
+		break;
+	case PROP_SORT_USER_DATA_NOTIFY:
+		g_value_set_pointer (value, self->sort_user_data_notify);
+		break;
+	case PROP_FILTER_FUNC:
+		g_value_set_pointer (value, self->filter_func);
+		break;
+	case PROP_FILTER_USER_DATA:
+		g_value_set_pointer (value, self->filter_user_data);
+		break;
+	case PROP_FILTER_USER_DATA_NOTIFY:
+		g_value_set_pointer (value, self->filter_user_data_notify);
+		break;
+	case PROP_DEPLOYMENT_FEATURED:
+		g_value_set_boxed (value, self->deployment_featured);
+		break;
+	case PROP_DEVELOPERS:
+		g_value_set_boxed (value, self->developers);
+		break;
+	case PROP_PROVIDES_FILES:
+		g_value_set_boxed (value, self->provides_files);
+		break;
+	case PROP_RELEASED_SINCE:
+		g_value_set_boxed (value, self->released_since);
+		break;
+	case PROP_IS_CURATED:
+		g_value_set_enum (value, self->is_curated);
+		break;
+	case PROP_IS_FEATURED:
+		g_value_set_enum (value, self->is_featured);
+		break;
+	case PROP_CATEGORY:
+		g_value_set_object (value, self->category);
+		break;
+	case PROP_IS_INSTALLED:
+		g_value_set_enum (value, self->is_installed);
+		break;
+	case PROP_KEYWORDS:
+		g_value_set_boxed (value, self->keywords);
+		break;
+	case PROP_ALTERNATE_OF:
+		g_value_set_object (value, self->alternate_of);
+		break;
+	case PROP_PROVIDES_TAG:
+		g_value_set_string (value, self->provides_tag);
+		break;
+	case PROP_PROVIDES_TYPE:
+		g_value_set_enum (value, self->provides_type);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_app_query_set_property (GObject      *object,
+                           guint         prop_id,
+                           const GValue *value,
+                           GParamSpec   *pspec)
+{
+	GsAppQuery *self = GS_APP_QUERY (object);
+
+	switch ((GsAppQueryProperty) prop_id) {
+	case PROP_REFINE_FLAGS:
+		/* Construct only. */
+		g_assert (self->refine_flags == 0);
+		self->refine_flags = g_value_get_flags (value);
+		break;
+	case PROP_MAX_RESULTS:
+		/* Construct only. */
+		g_assert (self->max_results == 0);
+		self->max_results = g_value_get_uint (value);
+		break;
+	case PROP_DEDUPE_FLAGS:
+		/* Construct only. */
+		g_assert (self->dedupe_flags == 0);
+		self->dedupe_flags = g_value_get_flags (value);
+		break;
+	case PROP_SORT_FUNC:
+		/* Construct only. */
+		g_assert (self->sort_func == NULL);
+		self->sort_func = g_value_get_pointer (value);
+		break;
+	case PROP_SORT_USER_DATA:
+		/* Construct only. */
+		g_assert (self->sort_user_data == NULL);
+		self->sort_user_data = g_value_get_pointer (value);
+		break;
+	case PROP_SORT_USER_DATA_NOTIFY:
+		/* Construct only. */
+		g_assert (self->sort_user_data_notify == NULL);
+		self->sort_user_data_notify = g_value_get_pointer (value);
+		break;
+	case PROP_FILTER_FUNC:
+		/* Construct only. */
+		g_assert (self->filter_func == NULL);
+		self->filter_func = g_value_get_pointer (value);
+		break;
+	case PROP_FILTER_USER_DATA:
+		/* Construct only. */
+		g_assert (self->filter_user_data == NULL);
+		self->filter_user_data = g_value_get_pointer (value);
+		break;
+	case PROP_FILTER_USER_DATA_NOTIFY:
+		/* Construct only. */
+		g_assert (self->filter_user_data_notify == NULL);
+		self->filter_user_data_notify = g_value_get_pointer (value);
+		break;
+	case PROP_DEPLOYMENT_FEATURED:
+		/* Construct only. */
+		g_assert (self->deployment_featured == NULL);
+		self->deployment_featured = g_value_dup_boxed (value);
+
+		/* Squash empty arrays to %NULL. */
+		if (self->deployment_featured != NULL && self->deployment_featured[0] == NULL)
+			g_clear_pointer (&self->deployment_featured, g_strfreev);
+
+		break;
+	case PROP_DEVELOPERS:
+		/* Construct only. */
+		g_assert (self->developers == NULL);
+		self->developers = g_value_dup_boxed (value);
+
+		/* Squash empty arrays to %NULL. */
+		if (self->developers != NULL && self->developers[0] == NULL)
+			g_clear_pointer (&self->developers, g_strfreev);
+
+		break;
+	case PROP_PROVIDES_FILES:
+		/* Construct only. */
+		g_assert (self->provides_files == NULL);
+		self->provides_files = g_value_dup_boxed (value);
+
+		/* Squash empty arrays to %NULL. */
+		if (self->provides_files != NULL && self->provides_files[0] == NULL)
+			g_clear_pointer (&self->provides_files, g_strfreev);
+
+		break;
+	case PROP_RELEASED_SINCE:
+		/* Construct only. */
+		g_assert (self->released_since == NULL);
+		self->released_since = g_value_dup_boxed (value);
+		break;
+	case PROP_IS_CURATED:
+		/* Construct only. */
+		g_assert (self->is_curated == GS_APP_QUERY_TRISTATE_UNSET);
+		self->is_curated = g_value_get_enum (value);
+		break;
+	case PROP_IS_FEATURED:
+		/* Construct only. */
+		g_assert (self->is_featured == GS_APP_QUERY_TRISTATE_UNSET);
+		self->is_featured = g_value_get_enum (value);
+		break;
+	case PROP_CATEGORY:
+		/* Construct only. */
+		g_assert (self->category == NULL);
+		self->category = g_value_dup_object (value);
+		break;
+	case PROP_IS_INSTALLED:
+		/* Construct only. */
+		g_assert (self->is_installed == GS_APP_QUERY_TRISTATE_UNSET);
+		self->is_installed = g_value_get_enum (value);
+		break;
+	case PROP_KEYWORDS:
+		/* Construct only. */
+		g_assert (self->keywords == NULL);
+		self->keywords = g_value_dup_boxed (value);
+
+		/* Squash empty arrays to %NULL. */
+		if (self->keywords != NULL && self->keywords[0] == NULL)
+			g_clear_pointer (&self->keywords, g_strfreev);
+
+		break;
+	case PROP_ALTERNATE_OF:
+		/* Construct only. */
+		g_assert (self->alternate_of == NULL);
+		self->alternate_of = g_value_dup_object (value);
+		break;
+	case PROP_PROVIDES_TAG:
+		/* Construct only. */
+		g_assert (self->provides_tag == NULL);
+		self->provides_tag = g_value_dup_string (value);
+		break;
+	case PROP_PROVIDES_TYPE:
+		/* Construct only. */
+		g_assert (self->provides_type == GS_APP_QUERY_PROVIDES_UNKNOWN);
+		self->provides_type = g_value_get_enum (value);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_app_query_dispose (GObject *object)
+{
+	GsAppQuery *self = GS_APP_QUERY (object);
+
+	if (self->sort_user_data_notify != NULL && self->sort_user_data != NULL) {
+		self->sort_user_data_notify (g_steal_pointer (&self->sort_user_data));
+		self->sort_user_data_notify = NULL;
+	}
+
+	if (self->filter_user_data_notify != NULL && self->filter_user_data != NULL) {
+		self->filter_user_data_notify (g_steal_pointer (&self->filter_user_data));
+		self->filter_user_data_notify = NULL;
+	}
+
+	g_clear_object (&self->category);
+	g_clear_object (&self->alternate_of);
+
+	G_OBJECT_CLASS (gs_app_query_parent_class)->dispose (object);
+}
+
+static void
+gs_app_query_finalize (GObject *object)
+{
+	GsAppQuery *self = GS_APP_QUERY (object);
+
+	g_clear_pointer (&self->deployment_featured, g_strfreev);
+	g_clear_pointer (&self->developers, g_strfreev);
+	g_clear_pointer (&self->provides_files, g_strfreev);
+	g_clear_pointer (&self->released_since, g_date_time_unref);
+	g_clear_pointer (&self->keywords, g_strfreev);
+	g_clear_pointer (&self->provides_tag, g_free);
+
+	G_OBJECT_CLASS (gs_app_query_parent_class)->finalize (object);
+}
+
+static void
+gs_app_query_class_init (GsAppQueryClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+	object_class->constructed = gs_app_query_constructed;
+	object_class->get_property = gs_app_query_get_property;
+	object_class->set_property = gs_app_query_set_property;
+	object_class->dispose = gs_app_query_dispose;
+	object_class->finalize = gs_app_query_finalize;
+
+	/**
+	 * GsAppQuery:refine-flags:
+	 *
+	 * Flags to specify how the returned apps must be refined, if at all.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_REFINE_FLAGS] =
+		g_param_spec_flags ("refine-flags", "Refine Flags",
+				    "Flags to specify how the returned apps must be refined, if at all.",
+				    GS_TYPE_PLUGIN_REFINE_FLAGS, GS_PLUGIN_REFINE_FLAGS_NONE,
+				    G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				    G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:max-results:
+	 *
+	 * Maximum number of results to return, or 0 for no limit.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_MAX_RESULTS] =
+		g_param_spec_uint ("max-results", "Max Results",
+				   "Maximum number of results to return, or 0 for no limit.",
+				   0, G_MAXUINT, 0,
+				   G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				   G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:dedupe-flags:
+	 *
+	 * Flags to specify how to deduplicate the returned apps, if at all.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_DEDUPE_FLAGS] =
+		g_param_spec_flags ("dedupe-flags", "Dedupe Flags",
+				    "Flags to specify how to deduplicate the returned apps, if at all.",
+				    GS_TYPE_APP_LIST_FILTER_FLAGS, GS_APP_LIST_FILTER_FLAG_NONE,
+				    G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				    G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:sort-func: (nullable)
+	 *
+	 * A sort function to sort the returned apps.
+	 *
+	 * This must be of type #GsAppListSortFunc.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_SORT_FUNC] =
+		g_param_spec_pointer ("sort-func", "Sort Function",
+				      "A sort function to sort the returned apps.",
+				      G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				      G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:sort-user-data: (nullable)
+	 *
+	 * User data to pass to #GsAppQuery:sort-func.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_SORT_USER_DATA] =
+		g_param_spec_pointer ("sort-user-data", "Sort User Data",
+				      "User data to pass to #GsAppQuery:sort-func.",
+				      G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				      G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:sort-user-data-notify: (nullable)
+	 *
+	 * A function to free #GsAppQuery:sort-user-data once it is no longer
+	 * needed.
+	 *
+	 * This must be of type #GDestroyNotify.
+	 *
+	 * This will be called exactly once between being set and when the
+	 * #GsAppQuery is finalized.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_SORT_USER_DATA_NOTIFY] =
+		g_param_spec_pointer ("sort-user-data-notify", "Sort User Data Notify",
+				      "A function to free #GsAppQuery:sort-user-data once it is no longer needed.",
+				      G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				      G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:filter-func: (nullable)
+	 *
+	 * A filter function to filter the returned apps.
+	 *
+	 * This must be of type #GsAppListFilterFunc.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_FILTER_FUNC] =
+		g_param_spec_pointer ("filter-func", "Filter Function",
+				      "A filter function to filter the returned apps.",
+				      G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				      G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:filter-user-data: (nullable)
+	 *
+	 * User data to pass to #GsAppQuery:filter-func.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_FILTER_USER_DATA] =
+		g_param_spec_pointer ("filter-user-data", "Filter User Data",
+				      "User data to pass to #GsAppQuery:filter-func.",
+				      G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				      G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:filter-user-data-notify: (nullable)
+	 *
+	 * A function to free #GsAppQuery:filter-user-data once it is no longer
+	 * needed.
+	 *
+	 * This must be of type #GDestroyNotify.
+	 *
+	 * This will be called exactly once between being set and when the
+	 * #GsAppQuery is finalized.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_FILTER_USER_DATA_NOTIFY] =
+		g_param_spec_pointer ("filter-user-data-notify", "Filter User Data Notify",
+				      "A function to free #GsAppQuery:filter-user-data once it is no longer needed.",
+				      G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				      G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:deployment-featured: (nullable)
+	 *
+	 * A list of `GnomeSoftware::DeploymentFeatured` app keys.
+	 *
+	 * Search for applications that should be featured in a deployment-specific
+	 * section on the overview page.
+	 * This is expected to be a curated list of applications that are high quality
+	 * and feature-complete. Only apps matching at least one of the keys in this
+	 * list are returned.
+	 *
+	 * This may be %NULL to not filter on it. An empty array is
+	 * considered equivalent to %NULL.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_DEPLOYMENT_FEATURED] =
+		g_param_spec_boxed ("deployment-featured", "Deployment Featured",
+				    "A list of `GnomeSoftware::DeploymentFeatured` app keys.",
+				    G_TYPE_STRV,
+				    G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				    G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:developers: (nullable)
+	 *
+	 * A list of developers to search the apps for.
+	 *
+	 * Used to search for apps which are provided by given developer(s).
+	 *
+	 * This may be %NULL to not filter on by them. An empty array is
+	 * considered equivalent to %NULL.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_DEVELOPERS] =
+		g_param_spec_boxed ("developers", "Developers",
+				    "A list of developers who provide the apps.",
+				    G_TYPE_STRV,
+				    G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				    G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:provides-files: (nullable)
+	 *
+	 * A list of file paths which the apps must provide.
+	 *
+	 * Used to search for apps which provide specific files on the local
+	 * file system.
+	 *
+	 * This may be %NULL to not filter on file paths. An empty array is
+	 * considered equivalent to %NULL.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_PROVIDES_FILES] =
+		g_param_spec_boxed ("provides-files", "Provides Files",
+				    "A list of file paths which the apps must provide.",
+				    G_TYPE_STRV,
+				    G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				    G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:released-since: (nullable)
+	 *
+	 * A date/time which apps must have been released since (exclusive).
+	 *
+	 * Used to search for apps which have been updated recently.
+	 *
+	 * This may be %NULL to not filter on release date.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_RELEASED_SINCE] =
+		g_param_spec_boxed ("released-since", "Released Since",
+				    "A date/time which apps must have been released since (exclusive).",
+				    G_TYPE_DATE_TIME,
+				    G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				    G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:is-curated:
+	 *
+	 * Whether apps must be curated (%GS_APP_QUERY_TRISTATE_TRUE), or not
+	 * curated (%GS_APP_QUERY_TRISTATE_FALSE).
+	 *
+	 * If this is %GS_APP_QUERY_TRISTATE_UNSET, apps are not filtered by
+	 * their curation state.
+	 *
+	 * ‘Curated’ apps have been reviewed and picked by an editor to be
+	 * promoted to users in some way. They should be high quality and
+	 * feature complete.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_IS_CURATED] =
+		g_param_spec_enum ("is-curated", "Is Curated",
+				   "Whether apps must be curated, or not curated.",
+				   GS_TYPE_APP_QUERY_TRISTATE,
+				   GS_APP_QUERY_TRISTATE_UNSET,
+				   G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				   G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:is-featured:
+	 *
+	 * Whether apps must be featured (%GS_APP_QUERY_TRISTATE_TRUE), or not
+	 * featured (%GS_APP_QUERY_TRISTATE_FALSE).
+	 *
+	 * If this is %GS_APP_QUERY_TRISTATE_UNSET, apps are not filtered by
+	 * their featured state.
+	 *
+	 * ‘Featured’ apps have been selected by the distribution or software
+	 * source to be highlighted or promoted to users in some way. They
+	 * should be high quality and feature complete.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_IS_FEATURED] =
+		g_param_spec_enum ("is-featured", "Is Featured",
+				   "Whether apps must be featured, or not featured.",
+				   GS_TYPE_APP_QUERY_TRISTATE,
+				   GS_APP_QUERY_TRISTATE_UNSET,
+				   G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				   G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:category: (nullable)
+	 *
+	 * A category which apps must be in.
+	 *
+	 * If this is %NULL, apps are not filtered by category.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_CATEGORY] =
+		g_param_spec_object ("category", "Category",
+				     "A category which apps must be in.",
+				     GS_TYPE_CATEGORY,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				     G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:is-installed:
+	 *
+	 * Whether apps must be installed (%GS_APP_QUERY_TRISTATE_TRUE), or not
+	 * installed (%GS_APP_QUERY_TRISTATE_FALSE).
+	 *
+	 * If this is %GS_APP_QUERY_TRISTATE_UNSET, apps are not filtered by
+	 * their installed state.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_IS_INSTALLED] =
+		g_param_spec_enum ("is-installed", "Is Installed",
+				   "Whether apps must be installed, or not installed.",
+				   GS_TYPE_APP_QUERY_TRISTATE,
+				   GS_APP_QUERY_TRISTATE_UNSET,
+				   G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				   G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:keywords:
+	 *
+	 * A set of search keywords which apps must match.
+	 *
+	 * Search matches may be done against multiple properties of the app,
+	 * such as its name, description, supported content types, defined
+	 * keywords, etc. The keywords in this property may be stemmed in an
+	 * undefined way after being retrieved from #GsAppQuery.
+	 *
+	 * If this is %NULL, apps are not filtered by matches to this set of
+	 * keywords. An empty array is considered equivalent to %NULL.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_KEYWORDS] =
+		g_param_spec_boxed ("keywords", "Keywords",
+				    "A set of search keywords which apps must match.",
+				    G_TYPE_STRV,
+				    G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				    G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:alternate-of: (nullable)
+	 *
+	 * An app which apps must be related to.
+	 *
+	 * The definition of ‘related to’ depends on the code consuming
+	 * #GsAppQuery, but it will typically be other applications which
+	 * implement the same feature, or other applications which are packaged
+	 * together with this one.
+	 *
+	 * If this is %NULL, apps are not filtered by alternatives.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_ALTERNATE_OF] =
+		g_param_spec_object ("alternate-of", "Alternate Of",
+				     "An app which apps must be related to.",
+				     GS_TYPE_APP,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				     G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:provides-tag: (nullable)
+	 *
+	 * A tag which apps must provide.
+	 *
+	 * The interpretation of the tag depends on #GsAppQuery:provides-type,
+	 * which must not be %GS_APP_QUERY_PROVIDES_UNKNOWN if this is
+	 * non-%NULL. Typically a tag will be a content type which the app
+	 * implements, or the name of a printer which the app provides the
+	 * driver for, etc.
+	 *
+	 * If this is %NULL, apps are not filtered by what they provide.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_PROVIDES_TAG] =
+		g_param_spec_string ("provides-tag", "Provides Tag",
+				     "A tag which apps must provide.",
+				     NULL,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				     G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsAppQuery:provides-type:
+	 *
+	 * The type of #GsAppQuery:provides-tag.
+	 *
+	 * If this is %GS_APP_QUERY_PROVIDES_UNKNOWN, apps are not filtered by
+	 * what they provide.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_PROVIDES_TYPE] =
+		g_param_spec_enum ("provides-type", "Provides Type",
+				   "The type of #GsAppQuery:provides-tag.",
+				   GS_TYPE_APP_QUERY_PROVIDES_TYPE, GS_APP_QUERY_PROVIDES_UNKNOWN,
+				   G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				   G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	g_object_class_install_properties (object_class, G_N_ELEMENTS (props), props);
+}
+
+static void
+gs_app_query_init (GsAppQuery *self)
+{
+	self->is_curated = GS_APP_QUERY_TRISTATE_UNSET;
+	self->is_featured = GS_APP_QUERY_TRISTATE_UNSET;
+	self->is_installed = GS_APP_QUERY_TRISTATE_UNSET;
+	self->provides_type = GS_APP_QUERY_PROVIDES_UNKNOWN;
+}
+
+/**
+ * gs_app_query_new:
+ * @first_property_name: name of the first #GObject property
+ * @...: value for the first property, followed by additional property/value
+ *   pairs, then a terminating %NULL
+ *
+ * Create a new #GsAppQuery containing the given query properties.
+ *
+ * Returns: (transfer full): a new #GsAppQuery
+ * Since: 43
+ */
+GsAppQuery *
+gs_app_query_new (const gchar *first_property_name,
+		  ...)
+{
+	va_list args;
+	g_autoptr(GsAppQuery) query = NULL;
+
+	va_start (args, first_property_name);
+	query = GS_APP_QUERY (g_object_new_valist (GS_TYPE_APP_QUERY, first_property_name, args));
+	va_end (args);
+
+	return g_steal_pointer (&query);
+}
+
+/**
+ * gs_app_query_get_refine_flags:
+ * @self: a #GsAppQuery
+ *
+ * Get the value of #GsAppQuery:refine-flags.
+ *
+ * Returns: the refine flags for the query
+ * Since: 43
+ */
+GsPluginRefineFlags
+gs_app_query_get_refine_flags (GsAppQuery *self)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), GS_PLUGIN_REFINE_FLAGS_NONE);
+
+	return self->refine_flags;
+}
+
+/**
+ * gs_app_query_get_max_results:
+ * @self: a #GsAppQuery
+ *
+ * Get the value of #GsAppQuery:max-results.
+ *
+ * Returns: the maximum number of results to return for the query, or `0` to
+ *   indicate no limit
+ * Since: 43
+ */
+guint
+gs_app_query_get_max_results (GsAppQuery *self)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), 0);
+
+	return self->max_results;
+}
+
+/**
+ * gs_app_query_get_dedupe_flags:
+ * @self: a #GsAppQuery
+ *
+ * Get the value of #GsAppQuery:dedupe-flags.
+ *
+ * Returns: the dedupe flags for the query
+ * Since: 43
+ */
+GsAppListFilterFlags
+gs_app_query_get_dedupe_flags (GsAppQuery *self)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), GS_APP_LIST_FILTER_FLAG_NONE);
+
+	return self->dedupe_flags;
+}
+
+/**
+ * gs_app_query_get_sort_func:
+ * @self: a #GsAppQuery
+ * @user_data_out: (out) (transfer none) (optional) (nullable): return location
+ *   for the #GsAppQuery:sort-user-data, or %NULL to ignore
+ *
+ * Get the value of #GsAppQuery:sort-func.
+ *
+ * Returns: (nullable): the sort function for the query
+ * Since: 43
+ */
+GsAppListSortFunc
+gs_app_query_get_sort_func (GsAppQuery *self,
+                            gpointer   *user_data_out)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), NULL);
+
+	if (user_data_out != NULL)
+		*user_data_out = self->sort_user_data;
+
+	return self->sort_func;
+}
+
+/**
+ * gs_app_query_get_filter_func:
+ * @self: a #GsAppQuery
+ * @user_data_out: (out) (transfer none) (optional) (nullable): return location
+ *   for the #GsAppQuery:filter-user-data, or %NULL to ignore
+ *
+ * Get the value of #GsAppQuery:filter-func.
+ *
+ * Returns: (nullable): the filter function for the query
+ * Since: 43
+ */
+GsAppListFilterFunc
+gs_app_query_get_filter_func (GsAppQuery *self,
+                              gpointer   *user_data_out)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), NULL);
+
+	if (user_data_out != NULL)
+		*user_data_out = self->filter_user_data;
+
+	return self->filter_func;
+}
+
+/**
+ * gs_app_query_get_n_properties_set:
+ * @self: a #GsAppQuery
+ *
+ * Get the number of query properties which have been set.
+ *
+ * These are the properties which determine the query results, rather than ones
+ * which control refining the results (#GsAppQuery:refine-flags,
+ * #GsAppQuery:max-results, #GsAppQuery:dedupe-flags, #GsAppQuery:sort-func and
+ * its user data, #GsAppQuery:filter-func and its user data).
+ *
+ * Returns: number of properties set so they will affect query results
+ * Since: 43
+ */
+guint
+gs_app_query_get_n_properties_set (GsAppQuery *self)
+{
+	guint n = 0;
+
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), 0);
+
+	if (self->provides_files != NULL)
+		n++;
+	if (self->released_since != NULL)
+		n++;
+	if (self->is_curated != GS_APP_QUERY_TRISTATE_UNSET)
+		n++;
+	if (self->is_featured != GS_APP_QUERY_TRISTATE_UNSET)
+		n++;
+	if (self->category != NULL)
+		n++;
+	if (self->is_installed != GS_APP_QUERY_TRISTATE_UNSET)
+		n++;
+	if (self->deployment_featured != NULL)
+		n++;
+	if (self->developers != NULL)
+		n++;
+	if (self->keywords != NULL)
+		n++;
+	if (self->alternate_of != NULL)
+		n++;
+	if (self->provides_tag != NULL)
+		n++;
+
+	return n;
+}
+
+/**
+ * gs_app_query_get_provides_files:
+ * @self: a #GsAppQuery
+ *
+ * Get the value of #GsAppQuery:provides-files.
+ *
+ * Returns: (nullable): a list of file paths which the apps must provide,
+ *   or %NULL to not filter on file paths
+ * Since: 43
+ */
+const gchar * const *
+gs_app_query_get_provides_files (GsAppQuery *self)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), NULL);
+
+	/* Always return %NULL or a non-empty array */
+	g_assert (self->provides_files == NULL || self->provides_files[0] != NULL);
+
+	return (const gchar * const *) self->provides_files;
+}
+
+/**
+ * gs_app_query_get_released_since:
+ * @self: a #GsAppQuery
+ *
+ * Get the value of #GsAppQuery:released-since.
+ *
+ * Returns: (nullable): a date/time which apps must have been released since,
+ *   or %NULL to not filter on release date
+ * Since: 43
+ */
+GDateTime *
+gs_app_query_get_released_since (GsAppQuery *self)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), NULL);
+
+	return self->released_since;
+}
+
+/**
+ * gs_app_query_get_is_curated:
+ * @self: a #GsAppQuery
+ *
+ * Get the value of #GsAppQuery:is-curated.
+ *
+ * Returns: %GS_APP_QUERY_TRISTATE_TRUE if apps must be curated,
+ *   %GS_APP_QUERY_TRISTATE_FALSE if they must be not curated, or
+ *   %GS_APP_QUERY_TRISTATE_UNSET if it doesn’t matter
+ * Since: 43
+ */
+GsAppQueryTristate
+gs_app_query_get_is_curated (GsAppQuery *self)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), GS_APP_QUERY_TRISTATE_UNSET);
+
+	return self->is_curated;
+}
+
+/**
+ * gs_app_query_get_is_featured:
+ * @self: a #GsAppQuery
+ *
+ * Get the value of #GsAppQuery:is-featured.
+ *
+ * Returns: %GS_APP_QUERY_TRISTATE_TRUE if apps must be featured,
+ *   %GS_APP_QUERY_TRISTATE_FALSE if they must be not featured, or
+ *   %GS_APP_QUERY_TRISTATE_UNSET if it doesn’t matter
+ * Since: 43
+ */
+GsAppQueryTristate
+gs_app_query_get_is_featured (GsAppQuery *self)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), GS_APP_QUERY_TRISTATE_UNSET);
+
+	return self->is_featured;
+}
+
+/**
+ * gs_app_query_get_category:
+ * @self: a #GsAppQuery
+ *
+ * Get the value of #GsAppQuery:category.
+ *
+ * Returns: (nullable) (transfer none): a category which apps must be part of,
+ *   or %NULL to not filter on category
+ * Since: 43
+ */
+GsCategory *
+gs_app_query_get_category (GsAppQuery *self)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), NULL);
+
+	return self->category;
+}
+
+/**
+ * gs_app_query_get_is_installed:
+ * @self: a #GsAppQuery
+ *
+ * Get the value of #GsAppQuery:is-installed.
+ *
+ * Returns: %GS_APP_QUERY_TRISTATE_TRUE if apps must be installed,
+ *   %GS_APP_QUERY_TRISTATE_FALSE if they must be not installed, or
+ *   %GS_APP_QUERY_TRISTATE_UNSET if it doesn’t matter
+ * Since: 43
+ */
+GsAppQueryTristate
+gs_app_query_get_is_installed (GsAppQuery *self)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), GS_APP_QUERY_TRISTATE_UNSET);
+
+	return self->is_installed;
+}
+
+/**
+ * gs_app_query_get_deployment_featured:
+ * @self: a #GsAppQuery
+ *
+ * Get the value of #GsAppQuery:deployment-featured.
+ *
+ * Returns: (nullable): a list of `GnomeSoftware::DeploymentFeatured` app keys,
+ *   which the apps have set in a custom key, or %NULL to not filter on this
+ * Since: 43
+ */
+const gchar * const *
+gs_app_query_get_deployment_featured (GsAppQuery *self)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), NULL);
+
+	/* Always return %NULL or a non-empty array */
+	g_assert (self->deployment_featured == NULL || self->deployment_featured[0] != NULL);
+
+	return (const gchar * const *) self->deployment_featured;
+}
+
+/**
+ * gs_app_query_get_developers:
+ * @self: a #GsAppQuery
+ *
+ * Get the value of #GsAppQuery:developers.
+ *
+ * Returns: (nullable): a list of developers who provide the apps,
+ *   or %NULL to not filter by it
+ * Since: 43
+ */
+const gchar * const *
+gs_app_query_get_developers (GsAppQuery *self)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), NULL);
+
+	/* Always return %NULL or a non-empty array */
+	g_assert (self->developers == NULL || self->developers[0] != NULL);
+
+	return (const gchar * const *) self->developers;
+}
+
+/**
+ * gs_app_query_get_keywords:
+ * @self: a #GsAppQuery
+ *
+ * Get the value of #GsAppQuery:keywords.
+ *
+ * Returns: a set of search keywords which apps must match, or %NULL to not
+ *   filter by it
+ * Since: 43
+ */
+const gchar * const *
+gs_app_query_get_keywords (GsAppQuery *self)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), NULL);
+
+	/* Always return %NULL or a non-empty array */
+	g_assert (self->keywords == NULL || self->keywords[0] != NULL);
+
+	return (const gchar * const *) self->keywords;
+}
+
+/**
+ * gs_app_query_get_alternate_of:
+ * @self: a #GsAppQuery
+ *
+ * Get the value of #GsAppQuery:alternate-of.
+ *
+ * Returns: (nullable) (transfer none): an app which apps must be related to,
+ *   or %NULL to not filter on alternates
+ * Since: 43
+ */
+GsApp *
+gs_app_query_get_alternate_of (GsAppQuery *self)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), NULL);
+
+	return self->alternate_of;
+}
+
+/**
+ * gs_app_query_get_provides:
+ * @self: a #GsAppQuery
+ * @out_provides_tag: (transfer none) (optional) (nullable) (out): return
+ *   location for the value of #GsAppQuery:provides-tag, or %NULL to ignore
+ *
+ * Get the value of #GsAppQuery:provides-type and #GsAppQuery:provides-tag.
+ *
+ * Returns: the type of tag to filter on, or %GS_APP_QUERY_PROVIDES_UNKNOWN to
+ *   not filter on provides
+ * Since: 43
+ */
+GsAppQueryProvidesType
+gs_app_query_get_provides (GsAppQuery   *self,
+                           const gchar **out_provides_tag)
+{
+	g_return_val_if_fail (GS_IS_APP_QUERY (self), GS_APP_QUERY_PROVIDES_UNKNOWN);
+
+	if (out_provides_tag != NULL)
+		*out_provides_tag = self->provides_tag;
+
+	return self->provides_type;
+}
diff --git a/lib/gs-app-query.h b/lib/gs-app-query.h
new file mode 100644
index 0000000..b66c56e
--- /dev/null
+++ b/lib/gs-app-query.h
@@ -0,0 +1,108 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2022 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <glib-object.h>
+#include <gio/gio.h>
+
+#include "gs-app-list.h"
+#include "gs-category.h"
+#include "gs-plugin-types.h"
+
+G_BEGIN_DECLS
+
+/**
+ * GsAppQueryTristate:
+ * @GS_APP_QUERY_TRISTATE_UNSET: Value is unset.
+ * @GS_APP_QUERY_TRISTATE_FALSE: False. Equal in value to %FALSE.
+ * @GS_APP_QUERY_TRISTATE_TRUE: True. Equal in value to %TRUE.
+ *
+ * A type for storing a boolean value which can also have an ‘unknown’ or
+ * ‘unset’ state.
+ *
+ * Within #GsAppQuery this is used for boolean query properties which are unset
+ * by default so that they don’t affect the query.
+ *
+ * Since: 43
+ */
+typedef enum
+{
+	GS_APP_QUERY_TRISTATE_UNSET = -1,
+	GS_APP_QUERY_TRISTATE_FALSE = 0,
+	GS_APP_QUERY_TRISTATE_TRUE = 1,
+} GsAppQueryTristate;
+
+/**
+ * GsAppQueryProvidesType:
+ * @GS_APP_QUERY_PROVIDES_UNKNOWN: Format is unknown and value is unset.
+ * @GS_APP_QUERY_PROVIDES_PACKAGE_NAME: A package name in whatever ID format is
+ *   used natively by the current distro.
+ * @GS_APP_QUERY_PROVIDES_GSTREAMER: A GStreamer plugin name which the app must
+ *   provide.
+ * @GS_APP_QUERY_PROVIDES_FONT: A font name which the app must provide.
+ * @GS_APP_QUERY_PROVIDES_MIME_HANDLER: A MIME type/content type which the app
+ *   must support.
+ * @GS_APP_QUERY_PROVIDES_PS_DRIVER: A printer/PostScript driver which the app
+ *   must provide.
+ * @GS_APP_QUERY_PROVIDES_PLASMA: A Plasma ID which the app must provide.
+ *   (FIXME: It’s not really clear what this means, but it’s historically been
+ *   supported.)
+ *
+ * A type for identifying the format or meaning of #GsAppQuery:provides-tag.
+ *
+ * This allows querying for apps which provide various types of functionality,
+ * such as printer drivers or fonts.
+ *
+ * Since: 43
+ */
+typedef enum {
+	GS_APP_QUERY_PROVIDES_UNKNOWN = 0,
+	GS_APP_QUERY_PROVIDES_PACKAGE_NAME,
+	GS_APP_QUERY_PROVIDES_GSTREAMER,
+	GS_APP_QUERY_PROVIDES_FONT,
+	GS_APP_QUERY_PROVIDES_MIME_HANDLER,
+	GS_APP_QUERY_PROVIDES_PS_DRIVER,
+	GS_APP_QUERY_PROVIDES_PLASMA,
+} GsAppQueryProvidesType;
+
+#define GS_TYPE_APP_QUERY (gs_app_query_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsAppQuery, gs_app_query, GS, APP_QUERY, GObject)
+
+GsAppQuery	*gs_app_query_new	(const gchar *first_property_name,
+					 ...) G_GNUC_NULL_TERMINATED;
+
+GsPluginRefineFlags	 gs_app_query_get_refine_flags	(GsAppQuery *self);
+guint			 gs_app_query_get_max_results	(GsAppQuery *self);
+GsAppListFilterFlags	 gs_app_query_get_dedupe_flags	(GsAppQuery *self);
+GsAppListSortFunc	 gs_app_query_get_sort_func	(GsAppQuery *self,
+							 gpointer   *user_data_out);
+GsAppListFilterFunc	 gs_app_query_get_filter_func	(GsAppQuery *self,
+							 gpointer   *user_data_out);
+
+guint			 gs_app_query_get_n_properties_set (GsAppQuery *self);
+
+const gchar * const	*gs_app_query_get_provides_files (GsAppQuery *self);
+GDateTime		*gs_app_query_get_released_since (GsAppQuery *self);
+GsAppQueryTristate	 gs_app_query_get_is_curated	 (GsAppQuery *self);
+GsAppQueryTristate	 gs_app_query_get_is_featured	 (GsAppQuery *self);
+GsCategory		*gs_app_query_get_category	 (GsAppQuery *self);
+GsAppQueryTristate	 gs_app_query_get_is_installed	 (GsAppQuery *self);
+const gchar * const	*gs_app_query_get_deployment_featured
+							 (GsAppQuery *self);
+const gchar * const	*gs_app_query_get_developers	 (GsAppQuery *self);
+const gchar * const	*gs_app_query_get_keywords	 (GsAppQuery *self);
+GsApp			*gs_app_query_get_alternate_of	 (GsAppQuery *self);
+GsAppQueryProvidesType	 gs_app_query_get_provides	 (GsAppQuery *self,
+							  const gchar **out_provides_tag);
+
+G_END_DECLS
diff --git a/lib/gs-app.c b/lib/gs-app.c
new file mode 100644
index 0000000..51215c7
--- /dev/null
+++ b/lib/gs-app.c
@@ -0,0 +1,6714 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2013-2016 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2013 Matthias Clasen <mclasen@redhat.com>
+ * Copyright (C) 2014-2018 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-app
+ * @title: GsApp
+ * @include: gnome-software.h
+ * @stability: Unstable
+ * @short_description: An application that is either installed or that can be installed
+ *
+ * For GsApps of kind %AS_COMPONENT_KIND_DESKTOP_APP, this object represents a 1:1 mapping
+ * to a .desktop file. The design is such so you can't have different GsApp's for different
+ * versions or architectures of a package. For other AppStream component types, GsApp maps
+ * their properties and %AS_COMPONENT_KIND_GENERIC is used if their type is a generic software
+ * component. For GNOME Software specific app-like entries, which don't correspond to desktop
+ * files or distinct software components, but e.g. represent a system update and its individual
+ * components, use the separate #GsAppSpecialKind enum and %gs_app_set_special_kind while setting
+ * the AppStream component-kind to generic.
+ *
+ * The #GsPluginLoader de-duplicates the GsApp instances that are produced by
+ * plugins to ensure that there is a single instance of GsApp for each id, making
+ * the id the primary key for this object. This ensures that actions triggered on
+ * a #GsApp in different parts of gnome-software can be observed by connecting to
+ * signals on the #GsApp.
+ *
+ * Information about other #GsApp objects can be stored in this object, for
+ * instance in the gs_app_add_related() method or gs_app_get_history().
+ */
+
+#include "config.h"
+
+#include <string.h>
+#include <gtk/gtk.h>
+#include <glib/gi18n.h>
+
+#include "gs-app-collation.h"
+#include "gs-app-private.h"
+#include "gs-desktop-data.h"
+#include "gs-enums.h"
+#include "gs-icon.h"
+#include "gs-key-colors.h"
+#include "gs-os-release.h"
+#include "gs-plugin.h"
+#include "gs-plugin-private.h"
+#include "gs-remote-icon.h"
+#include "gs-utils.h"
+
+typedef struct
+{
+	GMutex			 mutex;
+	gchar			*id;
+	gchar			*unique_id;
+	gboolean		 unique_id_valid;
+	gchar			*branch;
+	gchar			*name;
+	gchar			*renamed_from;
+	GsAppQuality		 name_quality;
+	GPtrArray		*icons;  /* (nullable) (owned) (element-type AsIcon), sorted by pixel size, smallest first */
+	GPtrArray		*sources;
+	GPtrArray		*source_ids;
+	gchar			*project_group;
+	gchar			*developer_name;
+	gchar			*agreement;
+	gchar			*version;
+	gchar			*version_ui;
+	gchar			*summary;
+	GsAppQuality		 summary_quality;
+	gchar			*summary_missing;
+	gchar			*description;
+	GsAppQuality		 description_quality;
+	GPtrArray		*screenshots;
+	GPtrArray		*categories;
+	GArray			*key_colors;  /* (nullable) (element-type GdkRGBA) */
+	gboolean		 user_key_colors;
+	GHashTable		*urls;  /* (element-type AsUrlKind utf8) (owned) (nullable) */
+	GHashTable		*launchables;
+	gchar			*url_missing;
+	gchar			*license;
+	GsAppQuality		 license_quality;
+	gchar			**menu_path;
+	gchar			*origin;
+	gchar			*origin_ui;
+	gchar			*origin_appstream;
+	gchar			*origin_hostname;
+	gchar			*update_version;
+	gchar			*update_version_ui;
+	gchar			*update_details_markup;
+	AsUrgencyKind		 update_urgency;
+	GsAppPermissions        *update_permissions;
+	GWeakRef		 management_plugin_weak;  /* (element-type GsPlugin) */
+	guint			 match_value;
+	guint			 priority;
+	gint			 rating;
+	GArray			*review_ratings;
+	GPtrArray		*reviews; /* of AsReview */
+	GPtrArray		*provided; /* of AsProvided */
+
+	GsSizeType		 size_installed_type;
+	guint64			 size_installed;
+	GsSizeType		 size_download_type;
+	guint64			 size_download;
+	GsSizeType		 size_user_data_type;
+	guint64			 size_user_data;
+	GsSizeType		 size_cache_data_type;
+	guint64			 size_cache_data;
+
+	AsComponentKind		 kind;
+	GsAppSpecialKind	 special_kind;
+	GsAppState		 state;
+	GsAppState		 state_recover;
+	AsComponentScope	 scope;
+	AsBundleKind		 bundle_kind;
+	guint			 progress;  /* integer 0–100 (inclusive), or %GS_APP_PROGRESS_UNKNOWN */
+	gboolean		 allow_cancel;
+	GHashTable		*metadata;
+	GsAppList		*addons;
+	GsAppList		*related;
+	GsAppList		*history;
+	guint64			 install_date;
+	guint64			 release_date;
+	guint64			 kudos;
+	gboolean		 to_be_installed;
+	GsAppQuirk		 quirk;
+	gboolean		 license_is_free;
+	GsApp			*runtime;
+	GFile			*local_file;
+	AsContentRating		*content_rating;
+	AsScreenshot		*action_screenshot;  /* (nullable) (owned) */
+	GCancellable		*cancellable;
+	GsPluginAction		 pending_action;
+	GsAppPermissions        *permissions;
+	gboolean		 is_update_downloaded;
+	GPtrArray		*version_history; /* (element-type AsRelease) (nullable) (owned) */
+	GPtrArray		*relations;  /* (nullable) (element-type AsRelation) (owned) */
+	gboolean		 has_translations;
+} GsAppPrivate;
+
+typedef enum {
+	PROP_ID = 1,
+	PROP_NAME,
+	PROP_VERSION,
+	PROP_SUMMARY,
+	PROP_DESCRIPTION,
+	PROP_RATING,
+	PROP_KIND,
+	PROP_SPECIAL_KIND,
+	PROP_STATE,
+	PROP_PROGRESS,
+	PROP_CAN_CANCEL_INSTALLATION,
+	PROP_INSTALL_DATE,
+	PROP_RELEASE_DATE,
+	PROP_QUIRK,
+	PROP_PENDING_ACTION,
+	PROP_KEY_COLORS,
+	PROP_IS_UPDATE_DOWNLOADED,
+	PROP_URLS,
+	PROP_URL_MISSING,
+	PROP_CONTENT_RATING,
+	PROP_LICENSE,
+	PROP_SIZE_CACHE_DATA_TYPE,
+	PROP_SIZE_CACHE_DATA,
+	PROP_SIZE_DOWNLOAD_TYPE,
+	PROP_SIZE_DOWNLOAD,
+	PROP_SIZE_DOWNLOAD_DEPENDENCIES_TYPE,
+	PROP_SIZE_DOWNLOAD_DEPENDENCIES,
+	PROP_SIZE_INSTALLED_TYPE,
+	PROP_SIZE_INSTALLED,
+	PROP_SIZE_INSTALLED_DEPENDENCIES_TYPE,
+	PROP_SIZE_INSTALLED_DEPENDENCIES,
+	PROP_SIZE_USER_DATA_TYPE,
+	PROP_SIZE_USER_DATA,
+	PROP_PERMISSIONS,
+	PROP_RELATIONS,
+	PROP_ORIGIN_UI,
+	PROP_HAS_TRANSLATIONS,
+} GsAppProperty;
+
+static GParamSpec *obj_props[PROP_HAS_TRANSLATIONS + 1] = { NULL, };
+
+G_DEFINE_TYPE_WITH_PRIVATE (GsApp, gs_app, G_TYPE_OBJECT)
+
+static gboolean
+_g_set_str (gchar **str_ptr, const gchar *new_str)
+{
+	if (*str_ptr == new_str || g_strcmp0 (*str_ptr, new_str) == 0)
+		return FALSE;
+	g_free (*str_ptr);
+	*str_ptr = g_strdup (new_str);
+	return TRUE;
+}
+
+static gboolean
+_g_set_strv (gchar ***strv_ptr, gchar **new_strv)
+{
+	if (*strv_ptr == new_strv)
+		return FALSE;
+	g_strfreev (*strv_ptr);
+	*strv_ptr = g_strdupv (new_strv);
+	return TRUE;
+}
+
+static gboolean
+_g_set_ptr_array (GPtrArray **array_ptr, GPtrArray *new_array)
+{
+	if (*array_ptr == new_array)
+		return FALSE;
+	if (new_array != NULL)
+		g_ptr_array_ref (new_array);
+	if (*array_ptr != NULL)
+		g_ptr_array_unref (*array_ptr);
+	*array_ptr = new_array;
+	return TRUE;
+}
+
+static gboolean
+_g_set_array (GArray **array_ptr, GArray *new_array)
+{
+	if (*array_ptr == new_array)
+		return FALSE;
+	if (new_array != NULL)
+		g_array_ref (new_array);
+	if (*array_ptr != NULL)
+		g_array_unref (*array_ptr);
+	*array_ptr = new_array;
+	return TRUE;
+}
+
+/**
+ * gs_app_state_to_string:
+ * @state: the #GsAppState.
+ *
+ * Converts the enumerated value to an text representation.
+ *
+ * Returns: string version of @state, or %NULL for unknown
+ **/
+const gchar *
+gs_app_state_to_string (GsAppState state)
+{
+	if (state == GS_APP_STATE_UNKNOWN)
+		return "unknown";
+	if (state == GS_APP_STATE_INSTALLED)
+		return "installed";
+	if (state == GS_APP_STATE_AVAILABLE)
+		return "available";
+	if (state == GS_APP_STATE_PURCHASABLE)
+		return "purchasable";
+	if (state == GS_APP_STATE_PURCHASING)
+		return "purchasing";
+	if (state == GS_APP_STATE_AVAILABLE_LOCAL)
+		return "local";
+	if (state == GS_APP_STATE_QUEUED_FOR_INSTALL)
+		return "queued";
+	if (state == GS_APP_STATE_INSTALLING)
+		return "installing";
+	if (state == GS_APP_STATE_REMOVING)
+		return "removing";
+	if (state == GS_APP_STATE_UPDATABLE)
+		return "updatable";
+	if (state == GS_APP_STATE_UPDATABLE_LIVE)
+		return "updatable-live";
+	if (state == GS_APP_STATE_UNAVAILABLE)
+		return "unavailable";
+	if (state == GS_APP_STATE_PENDING_INSTALL)
+		return "pending-install";
+	if (state == GS_APP_STATE_PENDING_REMOVE)
+		return "pending-remove";
+	return NULL;
+}
+
+static void
+gs_app_kv_lpad (GString *str, const gchar *key, const gchar *value)
+{
+	gs_utils_append_key_value (str, 20, key, value);
+}
+
+static void
+gs_app_kv_size (GString     *str,
+                const gchar *key,
+                GsSizeType   size_type,
+                guint64      value)
+{
+	g_autofree gchar *tmp = NULL;
+
+	switch (size_type) {
+	case GS_SIZE_TYPE_UNKNOWN:
+		gs_app_kv_lpad (str, key, "unknown");
+		break;
+	case GS_SIZE_TYPE_UNKNOWABLE:
+		gs_app_kv_lpad (str, key, "unknowable");
+		break;
+	case GS_SIZE_TYPE_VALID:
+		tmp = g_format_size (value);
+		gs_app_kv_lpad (str, key, tmp);
+		break;
+	default:
+		g_assert_not_reached ();
+	}
+}
+
+G_GNUC_PRINTF (3, 4)
+static void
+gs_app_kv_printf (GString *str, const gchar *key, const gchar *fmt, ...)
+{
+	va_list args;
+	g_autofree gchar *tmp = NULL;
+	va_start (args, fmt);
+	tmp = g_strdup_vprintf (fmt, args);
+	va_end (args);
+	gs_app_kv_lpad (str, key, tmp);
+}
+
+static const gchar *
+_as_component_quirk_flag_to_string (GsAppQuirk quirk)
+{
+	switch (quirk) {
+	case GS_APP_QUIRK_PROVENANCE:
+		return "provenance";
+	case GS_APP_QUIRK_COMPULSORY:
+		return "compulsory";
+	case GS_APP_QUIRK_HAS_SOURCE:
+		return "has-source";
+	case GS_APP_QUIRK_IS_WILDCARD:
+		return "is-wildcard";
+	case GS_APP_QUIRK_NEEDS_REBOOT:
+		return "needs-reboot";
+	case GS_APP_QUIRK_NOT_REVIEWABLE:
+		return "not-reviewable";
+	case GS_APP_QUIRK_NOT_LAUNCHABLE:
+		return "not-launchable";
+	case GS_APP_QUIRK_NEEDS_USER_ACTION:
+		return "needs-user-action";
+	case GS_APP_QUIRK_IS_PROXY:
+		return "is-proxy";
+	case GS_APP_QUIRK_REMOVABLE_HARDWARE:
+		return "removable-hardware";
+	case GS_APP_QUIRK_DEVELOPER_VERIFIED:
+		return "developer-verified";
+	case GS_APP_QUIRK_PARENTAL_FILTER:
+		return "parental-filter";
+	case GS_APP_QUIRK_NEW_PERMISSIONS:
+		return "new-permissions";
+	case GS_APP_QUIRK_PARENTAL_NOT_LAUNCHABLE:
+		return "parental-not-launchable";
+	case GS_APP_QUIRK_HIDE_FROM_SEARCH:
+		return "hide-from-search";
+	case GS_APP_QUIRK_HIDE_EVERYWHERE:
+		return "hide-everywhere";
+	case GS_APP_QUIRK_DO_NOT_AUTO_UPDATE:
+		return "do-not-auto-update";
+	default:
+		return NULL;
+	}
+}
+
+/* mutex must be held */
+static const gchar *
+gs_app_get_unique_id_unlocked (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	/* invalid */
+	if (priv->id == NULL)
+		return NULL;
+
+	/* hmm, do what we can */
+	if (priv->unique_id == NULL || !priv->unique_id_valid) {
+		g_free (priv->unique_id);
+		priv->unique_id = gs_utils_build_unique_id (priv->scope,
+							    priv->bundle_kind,
+							    priv->origin,
+							    priv->id,
+							    priv->branch);
+		priv->unique_id_valid = TRUE;
+	}
+	return priv->unique_id;
+}
+
+/**
+ * gs_app_compare_priority:
+ * @app1: a #GsApp
+ * @app2: a #GsApp
+ *
+ * Compares two applications using their priority.
+ *
+ * Use `gs_plugin_add_rule(plugin,GS_PLUGIN_RULE_BETTER_THAN,"plugin-name")`
+ * to set the application priority values.
+ *
+ * Returns: a negative value if @app1 is less than @app2, a positive value if
+ *          @app1 is greater than @app2, and zero if @app1 is equal to @app2
+ **/
+gint
+gs_app_compare_priority (GsApp *app1, GsApp *app2)
+{
+	GsAppPrivate *priv1 = gs_app_get_instance_private (app1);
+	GsAppPrivate *priv2 = gs_app_get_instance_private (app2);
+	guint prio1, prio2;
+
+	g_return_val_if_fail (GS_IS_APP (app1), 0);
+	g_return_val_if_fail (GS_IS_APP (app2), 0);
+
+	/* prefer prio */
+	prio1 = gs_app_get_priority (app1);
+	prio2 = gs_app_get_priority (app2);
+	if (prio1 > prio2)
+		return -1;
+	if (prio1 < prio2)
+		return 1;
+
+	/* fall back to bundle kind */
+	if (priv1->bundle_kind < priv2->bundle_kind)
+		return -1;
+	if (priv1->bundle_kind > priv2->bundle_kind)
+		return 1;
+	return 0;
+}
+
+/**
+ * gs_app_quirk_to_string:
+ * @quirk: a #GsAppQuirk
+ *
+ * Returns the quirk bitfield as a string.
+ *
+ * Returns: (transfer full): a string
+ **/
+static gchar *
+gs_app_quirk_to_string (GsAppQuirk quirk)
+{
+	GString *str = g_string_new ("");
+	guint64 i;
+
+	/* nothing set */
+	if (quirk == GS_APP_QUIRK_NONE) {
+		g_string_append (str, "none");
+		return g_string_free (str, FALSE);
+	}
+
+	/* get flags */
+	for (i = 1; i < GS_APP_QUIRK_LAST; i *= 2) {
+		if ((quirk & i) == 0)
+			continue;
+		g_string_append_printf (str, "%s,",
+					_as_component_quirk_flag_to_string (i));
+	}
+
+	/* nothing recognised */
+	if (str->len == 0) {
+		g_string_append (str, "unknown");
+		return g_string_free (str, FALSE);
+	}
+
+	/* remove trailing comma */
+	g_string_truncate (str, str->len - 1);
+	return g_string_free (str, FALSE);
+}
+
+static gchar *
+gs_app_kudos_to_string (guint64 kudos)
+{
+	g_autoptr(GPtrArray) array = g_ptr_array_new ();
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdiscarded-qualifiers"
+	if ((kudos & GS_APP_KUDO_MY_LANGUAGE) > 0)
+		g_ptr_array_add (array, "my-language");
+	if ((kudos & GS_APP_KUDO_RECENT_RELEASE) > 0)
+		g_ptr_array_add (array, "recent-release");
+	if ((kudos & GS_APP_KUDO_FEATURED_RECOMMENDED) > 0)
+		g_ptr_array_add (array, "featured-recommended");
+	if ((kudos & GS_APP_KUDO_MODERN_TOOLKIT) > 0)
+		g_ptr_array_add (array, "modern-toolkit");
+	if ((kudos & GS_APP_KUDO_SEARCH_PROVIDER) > 0)
+		g_ptr_array_add (array, "search-provider");
+	if ((kudos & GS_APP_KUDO_INSTALLS_USER_DOCS) > 0)
+		g_ptr_array_add (array, "installs-user-docs");
+	if ((kudos & GS_APP_KUDO_USES_NOTIFICATIONS) > 0)
+		g_ptr_array_add (array, "uses-notifications");
+	if ((kudos & GS_APP_KUDO_HAS_KEYWORDS) > 0)
+		g_ptr_array_add (array, "has-keywords");
+	if ((kudos & GS_APP_KUDO_HAS_SCREENSHOTS) > 0)
+		g_ptr_array_add (array, "has-screenshots");
+	if ((kudos & GS_APP_KUDO_HIGH_CONTRAST) > 0)
+		g_ptr_array_add (array, "high-contrast");
+	if ((kudos & GS_APP_KUDO_HI_DPI_ICON) > 0)
+		g_ptr_array_add (array, "hi-dpi-icon");
+	if ((kudos & GS_APP_KUDO_SANDBOXED) > 0)
+		g_ptr_array_add (array, "sandboxed");
+	if ((kudos & GS_APP_KUDO_SANDBOXED_SECURE) > 0)
+		g_ptr_array_add (array, "sandboxed-secure");
+#pragma GCC diagnostic pop
+	g_ptr_array_add (array, NULL);
+	return g_strjoinv ("|", (gchar **) array->pdata);
+}
+
+/**
+ * gs_app_to_string:
+ * @app: a #GsApp
+ *
+ * Converts the application to a string.
+ * This is not designed to serialize the object but to produce a string suitable
+ * for debugging.
+ *
+ * Returns: A multi-line string
+ *
+ * Since: 3.22
+ **/
+gchar *
+gs_app_to_string (GsApp *app)
+{
+	GString *str;
+
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+
+	str = g_string_new ("GsApp:");
+	gs_app_to_string_append (app, str);
+	if (str->len > 0)
+		g_string_truncate (str, str->len - 1);
+	return g_string_free (str, FALSE);
+}
+
+/**
+ * gs_app_to_string_append:
+ * @app: a #GsApp
+ * @str: a #GString
+ *
+ * Appends the application to an existing string.
+ *
+ * Since: 3.26
+ **/
+void
+gs_app_to_string_append (GsApp *app, GString *str)
+{
+	GsAppClass *klass;
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	AsImage *im;
+	GList *keys;
+	const gchar *tmp;
+	guint i;
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_autoptr(GsPlugin) management_plugin = NULL;
+	GsSizeType size_download_dependencies_type, size_installed_dependencies_type;
+	guint64 size_download_dependencies_bytes, size_installed_dependencies_bytes;
+
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (str != NULL);
+
+	klass = GS_APP_GET_CLASS (app);
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	g_string_append_printf (str, " [%p]\n", app);
+	gs_app_kv_lpad (str, "kind", as_component_kind_to_string (priv->kind));
+	gs_app_kv_lpad (str, "state", gs_app_state_to_string (priv->state));
+	if (priv->quirk > 0) {
+		g_autofree gchar *qstr = gs_app_quirk_to_string (priv->quirk);
+		gs_app_kv_lpad (str, "quirk", qstr);
+	}
+	if (priv->progress == GS_APP_PROGRESS_UNKNOWN)
+		gs_app_kv_printf (str, "progress", "unknown");
+	else
+		gs_app_kv_printf (str, "progress", "%u%%", priv->progress);
+	if (priv->id != NULL)
+		gs_app_kv_lpad (str, "id", priv->id);
+	if (priv->unique_id != NULL)
+		gs_app_kv_lpad (str, "unique-id", priv->unique_id);
+	if (priv->scope != AS_COMPONENT_SCOPE_UNKNOWN)
+		gs_app_kv_lpad (str, "scope", as_component_scope_to_string (priv->scope));
+	if (priv->bundle_kind != AS_BUNDLE_KIND_UNKNOWN) {
+		gs_app_kv_lpad (str, "bundle-kind",
+				as_bundle_kind_to_string (priv->bundle_kind));
+	}
+	if (priv->kudos > 0) {
+		g_autofree gchar *kudo_str = NULL;
+		kudo_str = gs_app_kudos_to_string (priv->kudos);
+		gs_app_kv_lpad (str, "kudos", kudo_str);
+	}
+	gs_app_kv_printf (str, "kudo-percentage", "%u",
+			  gs_app_get_kudos_percentage (app));
+	if (priv->name != NULL)
+		gs_app_kv_lpad (str, "name", priv->name);
+	if (priv->action_screenshot != NULL)
+		gs_app_kv_printf (str, "action-screenshot", "%p", priv->action_screenshot);
+	for (i = 0; priv->icons != NULL && i < priv->icons->len; i++) {
+		GIcon *icon = g_ptr_array_index (priv->icons, i);
+		g_autofree gchar *icon_str = g_icon_to_string (icon);
+		gs_app_kv_lpad (str, "icon", icon_str);
+	}
+	if (priv->match_value != 0)
+		gs_app_kv_printf (str, "match-value", "%05x", priv->match_value);
+	if (gs_app_get_priority (app) != 0)
+		gs_app_kv_printf (str, "priority", "%u", gs_app_get_priority (app));
+	if (priv->version != NULL)
+		gs_app_kv_lpad (str, "version", priv->version);
+	if (priv->version_ui != NULL)
+		gs_app_kv_lpad (str, "version-ui", priv->version_ui);
+	if (priv->update_version != NULL)
+		gs_app_kv_lpad (str, "update-version", priv->update_version);
+	if (priv->update_version_ui != NULL)
+		gs_app_kv_lpad (str, "update-version-ui", priv->update_version_ui);
+	if (priv->update_details_markup != NULL)
+		gs_app_kv_lpad (str, "update-details-markup", priv->update_details_markup);
+	if (priv->update_urgency != AS_URGENCY_KIND_UNKNOWN) {
+		gs_app_kv_printf (str, "update-urgency", "%u",
+				  priv->update_urgency);
+	}
+	if (priv->summary != NULL)
+		gs_app_kv_lpad (str, "summary", priv->summary);
+	if (priv->description != NULL)
+		gs_app_kv_lpad (str, "description", priv->description);
+	for (i = 0; i < priv->screenshots->len; i++) {
+		AsScreenshot *ss = g_ptr_array_index (priv->screenshots, i);
+		g_autofree gchar *key = NULL;
+		tmp = as_screenshot_get_caption (ss);
+		im = as_screenshot_get_image (ss, 0, 0);
+		if (im == NULL)
+			continue;
+		key = g_strdup_printf ("screenshot-%02u", i);
+		gs_app_kv_printf (str, key, "%s [%s]",
+				  as_image_get_url (im),
+				  tmp != NULL ? tmp : "<none>");
+	}
+	for (i = 0; i < priv->sources->len; i++) {
+		g_autofree gchar *key = NULL;
+		tmp = g_ptr_array_index (priv->sources, i);
+		key = g_strdup_printf ("source-%02u", i);
+		gs_app_kv_lpad (str, key, tmp);
+	}
+	for (i = 0; i < priv->source_ids->len; i++) {
+		g_autofree gchar *key = NULL;
+		tmp = g_ptr_array_index (priv->source_ids, i);
+		key = g_strdup_printf ("source-id-%02u", i);
+		gs_app_kv_lpad (str, key, tmp);
+	}
+	if (priv->local_file != NULL) {
+		g_autofree gchar *fn = g_file_get_path (priv->local_file);
+		gs_app_kv_lpad (str, "local-filename", fn);
+	}
+	if (priv->content_rating != NULL) {
+		guint age = as_content_rating_get_minimum_age (priv->content_rating);
+		if (age != G_MAXUINT) {
+			g_autofree gchar *value = g_strdup_printf ("%u", age);
+			gs_app_kv_lpad (str, "content-age", value);
+		}
+		gs_app_kv_lpad (str, "content-rating",
+				as_content_rating_get_kind (priv->content_rating));
+	}
+	if (priv->urls != NULL) {
+		tmp = g_hash_table_lookup (priv->urls, GINT_TO_POINTER (AS_URL_KIND_HOMEPAGE));
+		if (tmp != NULL)
+			gs_app_kv_lpad (str, "url{homepage}", tmp);
+	}
+	keys = g_hash_table_get_keys (priv->launchables);
+	for (GList *l = keys; l != NULL; l = l->next) {
+		g_autofree gchar *key = NULL;
+		key = g_strdup_printf ("launchable{%s}", (const gchar *) l->data);
+		tmp = g_hash_table_lookup (priv->launchables, l->data);
+		gs_app_kv_lpad (str, key, tmp);
+	}
+	g_list_free (keys);
+	if (priv->license != NULL) {
+		gs_app_kv_lpad (str, "license", priv->license);
+		gs_app_kv_lpad (str, "license-is-free",
+				gs_app_get_license_is_free (app) ? "yes" : "no");
+	}
+	management_plugin = g_weak_ref_get (&priv->management_plugin_weak);
+	if (management_plugin != NULL)
+		gs_app_kv_lpad (str, "management-plugin", gs_plugin_get_name (management_plugin));
+	if (priv->summary_missing != NULL)
+		gs_app_kv_lpad (str, "summary-missing", priv->summary_missing);
+	if (priv->menu_path != NULL &&
+	    priv->menu_path[0] != NULL &&
+	    priv->menu_path[0][0] != '\0') {
+		g_autofree gchar *path = g_strjoinv (" → ", priv->menu_path);
+		gs_app_kv_lpad (str, "menu-path", path);
+	}
+	if (priv->branch != NULL)
+		gs_app_kv_lpad (str, "branch", priv->branch);
+	if (priv->origin != NULL && priv->origin[0] != '\0')
+		gs_app_kv_lpad (str, "origin", priv->origin);
+	if (priv->origin_ui != NULL && priv->origin_ui[0] != '\0')
+		gs_app_kv_lpad (str, "origin-ui", priv->origin_ui);
+	if (priv->origin_appstream != NULL && priv->origin_appstream[0] != '\0')
+		gs_app_kv_lpad (str, "origin-appstream", priv->origin_appstream);
+	if (priv->origin_hostname != NULL && priv->origin_hostname[0] != '\0')
+		gs_app_kv_lpad (str, "origin-hostname", priv->origin_hostname);
+	if (priv->rating != -1)
+		gs_app_kv_printf (str, "rating", "%i", priv->rating);
+	if (priv->review_ratings != NULL) {
+		for (i = 0; i < priv->review_ratings->len; i++) {
+			guint32 rat = g_array_index (priv->review_ratings, guint32, i);
+			gs_app_kv_printf (str, "review-rating", "[%u:%u]",
+					  i, rat);
+		}
+	}
+	if (priv->reviews != NULL)
+		gs_app_kv_printf (str, "reviews", "%u", priv->reviews->len);
+	if (priv->provided != NULL) {
+		guint total = 0;
+		for (i = 0; i < priv->provided->len; i++)
+			total += as_provided_get_items (AS_PROVIDED (g_ptr_array_index (priv->provided, i)))->len;
+		gs_app_kv_printf (str, "provided", "%u", total);
+	}
+	if (priv->install_date != 0) {
+		gs_app_kv_printf (str, "install-date", "%"
+				  G_GUINT64_FORMAT "",
+				  priv->install_date);
+	}
+	if (priv->release_date != 0) {
+		gs_app_kv_printf (str, "release-date", "%"
+				  G_GUINT64_FORMAT "",
+				  priv->release_date);
+	}
+
+	gs_app_kv_size (str, "size-installed", priv->size_installed_type, priv->size_installed);
+	size_installed_dependencies_type = gs_app_get_size_installed_dependencies (app, &size_installed_dependencies_bytes);
+	gs_app_kv_size (str, "size-installed-dependencies", size_installed_dependencies_type, size_installed_dependencies_bytes);
+	gs_app_kv_size (str, "size-download", priv->size_download_type, priv->size_download);
+	size_download_dependencies_type = gs_app_get_size_download_dependencies (app, &size_download_dependencies_bytes);
+	gs_app_kv_size (str, "size-download-dependencies", size_download_dependencies_type, size_download_dependencies_bytes);
+	gs_app_kv_size (str, "size-cache-data", priv->size_cache_data_type, priv->size_cache_data);
+	gs_app_kv_size (str, "size-user-data", priv->size_user_data_type, priv->size_user_data);
+
+	for (i = 0; i < gs_app_list_length (priv->related); i++) {
+		GsApp *app_tmp = gs_app_list_index (priv->related, i);
+		const gchar *id = gs_app_get_unique_id (app_tmp);
+		if (id == NULL)
+			id = gs_app_get_source_default (app_tmp);
+		/* For example PackageKit can create apps without id */
+		if (id != NULL)
+			gs_app_kv_lpad (str, "related", id);
+	}
+	for (i = 0; i < gs_app_list_length (priv->history); i++) {
+		GsApp *app_tmp = gs_app_list_index (priv->history, i);
+		const gchar *id = gs_app_get_unique_id (app_tmp);
+		if (id == NULL)
+			id = gs_app_get_source_default (app_tmp);
+		/* For example PackageKit can create apps without id */
+		if (id != NULL)
+			gs_app_kv_lpad (str, "history", id);
+	}
+	for (i = 0; i < priv->categories->len; i++) {
+		tmp = g_ptr_array_index (priv->categories, i);
+		gs_app_kv_lpad (str, "category", tmp);
+	}
+	if (priv->user_key_colors)
+		gs_app_kv_lpad (str, "user-key-colors", "yes");
+	for (i = 0; priv->key_colors != NULL && i < priv->key_colors->len; i++) {
+		GdkRGBA *color = &g_array_index (priv->key_colors, GdkRGBA, i);
+		g_autofree gchar *key = NULL;
+		key = g_strdup_printf ("key-color-%02u", i);
+		gs_app_kv_printf (str, key, "%.0f,%.0f,%.0f",
+				  color->red * 255.f,
+				  color->green * 255.f,
+				  color->blue * 255.f);
+	}
+	keys = g_hash_table_get_keys (priv->metadata);
+	for (GList *l = keys; l != NULL; l = l->next) {
+		GVariant *val;
+		const GVariantType *val_type;
+		g_autofree gchar *key = NULL;
+		g_autofree gchar *val_str = NULL;
+
+		key = g_strdup_printf ("{%s}", (const gchar *) l->data);
+		val = g_hash_table_lookup (priv->metadata, l->data);
+		val_type = g_variant_get_type (val);
+		if (g_variant_type_equal (val_type, G_VARIANT_TYPE_STRING)) {
+			val_str = g_variant_dup_string (val, NULL);
+		} else if (g_variant_type_equal (val_type, G_VARIANT_TYPE_BOOLEAN)) {
+			val_str = g_strdup (g_variant_get_boolean (val) ? "True" : "False");
+		} else if (g_variant_type_equal (val_type, G_VARIANT_TYPE_UINT32)) {
+			val_str = g_strdup_printf ("%" G_GUINT32_FORMAT,
+						   g_variant_get_uint32 (val));
+		} else {
+			val_str = g_strdup_printf ("unknown type of %s",
+						   g_variant_get_type_string (val));
+		}
+		gs_app_kv_lpad (str, key, val_str);
+	}
+	g_list_free (keys);
+
+	for (i = 0; priv->relations != NULL && i < priv->relations->len; i++) {
+		AsRelation *relation = g_ptr_array_index (priv->relations, i);
+		gs_app_kv_printf (str, "relation", "%s, %s",
+				  as_relation_kind_to_string (as_relation_get_kind (relation)),
+				  as_relation_item_kind_to_string (as_relation_get_item_kind (relation)));
+	}
+
+	/* add subclassed info */
+	if (klass->to_string != NULL)
+		klass->to_string (app, str);
+
+	/* print runtime data too */
+	if (priv->runtime != NULL) {
+		g_string_append (str, "\n\tRuntime:\n\t");
+		gs_app_to_string_append (priv->runtime, str);
+	}
+	g_string_append_printf (str, "\n");
+}
+
+typedef struct {
+	GsApp *app;
+	GParamSpec *pspec;
+} AppNotifyData;
+
+static gboolean
+notify_idle_cb (gpointer data)
+{
+	AppNotifyData *notify_data = data;
+
+	g_object_notify_by_pspec (G_OBJECT (notify_data->app), notify_data->pspec);
+
+	g_object_unref (notify_data->app);
+	g_free (notify_data);
+
+	return G_SOURCE_REMOVE;
+}
+
+static void
+gs_app_queue_notify (GsApp *app, GParamSpec *pspec)
+{
+	AppNotifyData *notify_data;
+
+	notify_data = g_new (AppNotifyData, 1);
+	notify_data->app = g_object_ref (app);
+	notify_data->pspec = pspec;
+
+	g_idle_add (notify_idle_cb, notify_data);
+}
+
+/**
+ * gs_app_get_id:
+ * @app: a #GsApp
+ *
+ * Gets the application ID.
+ *
+ * Returns: The whole ID, e.g. "gimp.desktop"
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_id (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->id;
+}
+
+/**
+ * gs_app_set_id:
+ * @app: a #GsApp
+ * @id: a application ID, e.g. "gimp.desktop"
+ *
+ * Sets the application ID.
+ */
+void
+gs_app_set_id (GsApp *app, const gchar *id)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	if (_g_set_str (&priv->id, id))
+		priv->unique_id_valid = FALSE;
+}
+
+/**
+ * gs_app_get_scope:
+ * @app: a #GsApp
+ *
+ * Gets the scope of the application.
+ *
+ * Returns: the #AsComponentScope, e.g. %AS_COMPONENT_SCOPE_USER
+ *
+ * Since: 40
+ **/
+AsComponentScope
+gs_app_get_scope (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), AS_COMPONENT_SCOPE_UNKNOWN);
+	return priv->scope;
+}
+
+/**
+ * gs_app_set_scope:
+ * @app: a #GsApp
+ * @scope: a #AsComponentScope, e.g. %AS_COMPONENT_SCOPE_SYSTEM
+ *
+ * This sets the scope of the application.
+ *
+ * Since: 40
+ **/
+void
+gs_app_set_scope (GsApp *app, AsComponentScope scope)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	g_return_if_fail (GS_IS_APP (app));
+
+	/* same */
+	if (scope == priv->scope)
+		return;
+
+	priv->scope = scope;
+
+	/* no longer valid */
+	priv->unique_id_valid = FALSE;
+}
+
+/**
+ * gs_app_get_bundle_kind:
+ * @app: a #GsApp
+ *
+ * Gets the bundle kind of the application.
+ *
+ * Returns: the #AsComponentScope, e.g. %AS_BUNDLE_KIND_FLATPAK
+ *
+ * Since: 40
+ **/
+AsBundleKind
+gs_app_get_bundle_kind (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), AS_BUNDLE_KIND_UNKNOWN);
+	return priv->bundle_kind;
+}
+
+/**
+ * gs_app_set_bundle_kind:
+ * @app: a #GsApp
+ * @bundle_kind: a #AsComponentScope, e.g. AS_BUNDLE_KIND_FLATPAK
+ *
+ * This sets the bundle kind of the application.
+ *
+ * Since: 40
+ **/
+void
+gs_app_set_bundle_kind (GsApp *app, AsBundleKind bundle_kind)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	g_return_if_fail (GS_IS_APP (app));
+
+	/* same */
+	if (bundle_kind == priv->bundle_kind)
+		return;
+
+	priv->bundle_kind = bundle_kind;
+
+	/* no longer valid */
+	priv->unique_id_valid = FALSE;
+}
+
+/**
+ * gs_app_get_special_kind:
+ * @app: a #GsApp
+ *
+ * Gets the special occupation of the application.
+ *
+ * Returns: the #GsAppSpecialKind, e.g. %GS_APP_SPECIAL_KIND_OS_UPDATE
+ *
+ * Since: 40
+ **/
+GsAppSpecialKind
+gs_app_get_special_kind (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), GS_APP_SPECIAL_KIND_NONE);
+	return priv->special_kind;
+}
+
+/**
+ * gs_app_set_special_kind:
+ * @app: a #GsApp
+ * @kind: a #GsAppSpecialKind, e.g. %GS_APP_SPECIAL_KIND_OS_UPDATE
+ *
+ * This sets the special occupation of the application (making
+ * the #AsComponentKind of this application %AS_COMPONENT_KIND_GENERIC
+ * per definition).
+ *
+ * Since: 40
+ **/
+void
+gs_app_set_special_kind	(GsApp *app, GsAppSpecialKind kind)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_if_fail (GS_IS_APP (app));
+
+	if (priv->special_kind == kind)
+		return;
+	gs_app_set_kind (app, AS_COMPONENT_KIND_GENERIC);
+	priv->special_kind = kind;
+	gs_app_queue_notify (app, obj_props[PROP_SPECIAL_KIND]);
+}
+
+/**
+ * gs_app_get_state:
+ * @app: a #GsApp
+ *
+ * Gets the state of the application.
+ *
+ * Returns: the #GsAppState, e.g. %GS_APP_STATE_INSTALLED
+ *
+ * Since: 40
+ **/
+GsAppState
+gs_app_get_state (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), GS_APP_STATE_UNKNOWN);
+	return priv->state;
+}
+
+/**
+ * gs_app_get_progress:
+ * @app: a #GsApp
+ *
+ * Gets the percentage completion.
+ *
+ * Returns: the percentage completion (0–100 inclusive), or %GS_APP_PROGRESS_UNKNOWN for unknown
+ *
+ * Since: 3.22
+ **/
+guint
+gs_app_get_progress (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), GS_APP_PROGRESS_UNKNOWN);
+	return priv->progress;
+}
+
+/**
+ * gs_app_get_allow_cancel:
+ * @app: a #GsApp
+ *
+ * Gets whether the app's installation or upgrade can be cancelled.
+ *
+ * Returns: TRUE if cancellation is possible, FALSE otherwise.
+ *
+ * Since: 3.26
+ **/
+gboolean
+gs_app_get_allow_cancel (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+	return priv->allow_cancel;
+}
+
+/**
+ * gs_app_set_state_recover:
+ * @app: a #GsApp
+ *
+ * Sets the application state to the last status value that was not
+ * transient.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_state_recover (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	g_return_if_fail (GS_IS_APP (app));
+
+	if (priv->state_recover == GS_APP_STATE_UNKNOWN)
+		return;
+	if (priv->state_recover == priv->state)
+		return;
+
+	g_debug ("recovering state on %s from %s to %s",
+		 priv->id,
+		 gs_app_state_to_string (priv->state),
+		 gs_app_state_to_string (priv->state_recover));
+
+	/* make sure progress gets reset when recovering state, to prevent
+	 * confusing initial states when going through more than one attempt */
+	gs_app_set_progress (app, GS_APP_PROGRESS_UNKNOWN);
+
+	priv->state = priv->state_recover;
+	gs_app_queue_notify (app, obj_props[PROP_STATE]);
+}
+
+/* mutex must be held */
+static gboolean
+gs_app_set_state_internal (GsApp *app, GsAppState state)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	gboolean state_change_ok = FALSE;
+
+	/* same */
+	if (priv->state == state)
+		return FALSE;
+
+	/* check the state change is allowed */
+	switch (priv->state) {
+	case GS_APP_STATE_UNKNOWN:
+		/* unknown has to go into one of the stable states */
+		if (state == GS_APP_STATE_INSTALLED ||
+		    state == GS_APP_STATE_QUEUED_FOR_INSTALL ||
+		    state == GS_APP_STATE_AVAILABLE ||
+		    state == GS_APP_STATE_AVAILABLE_LOCAL ||
+		    state == GS_APP_STATE_UPDATABLE ||
+		    state == GS_APP_STATE_UPDATABLE_LIVE ||
+		    state == GS_APP_STATE_UNAVAILABLE ||
+		    state == GS_APP_STATE_PENDING_INSTALL ||
+		    state == GS_APP_STATE_PENDING_REMOVE)
+			state_change_ok = TRUE;
+		break;
+	case GS_APP_STATE_INSTALLED:
+		/* installed has to go into an action state */
+		if (state == GS_APP_STATE_UNKNOWN ||
+		    state == GS_APP_STATE_REMOVING ||
+		    state == GS_APP_STATE_UNAVAILABLE ||
+		    state == GS_APP_STATE_UPDATABLE ||
+		    state == GS_APP_STATE_UPDATABLE_LIVE)
+			state_change_ok = TRUE;
+		break;
+	case GS_APP_STATE_QUEUED_FOR_INSTALL:
+		if (state == GS_APP_STATE_UNKNOWN ||
+		    state == GS_APP_STATE_INSTALLING ||
+		    state == GS_APP_STATE_AVAILABLE)
+			state_change_ok = TRUE;
+		break;
+	case GS_APP_STATE_AVAILABLE:
+		/* available has to go into an action state */
+		if (state == GS_APP_STATE_UNKNOWN ||
+		    state == GS_APP_STATE_QUEUED_FOR_INSTALL ||
+		    state == GS_APP_STATE_INSTALLING)
+			state_change_ok = TRUE;
+		break;
+	case GS_APP_STATE_INSTALLING:
+		/* installing has to go into an stable state */
+		if (state == GS_APP_STATE_UNKNOWN ||
+		    state == GS_APP_STATE_INSTALLED ||
+		    state == GS_APP_STATE_UPDATABLE ||
+		    state == GS_APP_STATE_UPDATABLE_LIVE ||
+		    state == GS_APP_STATE_AVAILABLE ||
+		    state == GS_APP_STATE_PENDING_INSTALL)
+			state_change_ok = TRUE;
+		break;
+	case GS_APP_STATE_REMOVING:
+		/* removing has to go into an stable state */
+		if (state == GS_APP_STATE_UNKNOWN ||
+		    state == GS_APP_STATE_UNAVAILABLE ||
+		    state == GS_APP_STATE_AVAILABLE ||
+		    state == GS_APP_STATE_INSTALLED ||
+		    state == GS_APP_STATE_PENDING_REMOVE)
+			state_change_ok = TRUE;
+		break;
+	case GS_APP_STATE_UPDATABLE:
+		/* updatable has to go into an action state */
+		if (state == GS_APP_STATE_UNKNOWN ||
+		    state == GS_APP_STATE_REMOVING ||
+		    state == GS_APP_STATE_INSTALLING)
+			state_change_ok = TRUE;
+		break;
+	case GS_APP_STATE_UPDATABLE_LIVE:
+		/* updatable-live has to go into an action state */
+		if (state == GS_APP_STATE_UNKNOWN ||
+		    state == GS_APP_STATE_REMOVING ||
+		    state == GS_APP_STATE_INSTALLING)
+			state_change_ok = TRUE;
+		break;
+	case GS_APP_STATE_UNAVAILABLE:
+		/* updatable has to go into an action state */
+		if (state == GS_APP_STATE_UNKNOWN ||
+		    state == GS_APP_STATE_AVAILABLE)
+			state_change_ok = TRUE;
+		break;
+	case GS_APP_STATE_AVAILABLE_LOCAL:
+		/* local has to go into an action state */
+		if (state == GS_APP_STATE_UNKNOWN ||
+		    state == GS_APP_STATE_QUEUED_FOR_INSTALL ||
+		    state == GS_APP_STATE_INSTALLING)
+			state_change_ok = TRUE;
+		break;
+	case GS_APP_STATE_PENDING_INSTALL:
+	case GS_APP_STATE_PENDING_REMOVE:
+		state_change_ok = TRUE;
+		break;
+	default:
+		g_warning ("state %s unhandled",
+			   gs_app_state_to_string (priv->state));
+		g_assert_not_reached ();
+	}
+
+	/* this state change was unexpected */
+	if (!state_change_ok) {
+		g_warning ("State change on %s (%s) from %s to %s is not OK",
+			   gs_app_get_unique_id_unlocked (app),
+			   priv->name,
+			   gs_app_state_to_string (priv->state),
+			   gs_app_state_to_string (state));
+	}
+
+	priv->state = state;
+
+	if (state == GS_APP_STATE_UNKNOWN ||
+	    state == GS_APP_STATE_AVAILABLE_LOCAL ||
+	    state == GS_APP_STATE_AVAILABLE)
+		priv->install_date = 0;
+
+	/* save this to simplify error handling in the plugins */
+	switch (state) {
+	case GS_APP_STATE_INSTALLING:
+	case GS_APP_STATE_REMOVING:
+	case GS_APP_STATE_QUEUED_FOR_INSTALL:
+		/* transient, so ignore */
+		break;
+	default:
+		if (priv->state_recover != state)
+			priv->state_recover = state;
+		break;
+	}
+
+	return TRUE;
+}
+
+/**
+ * gs_app_set_progress:
+ * @app: a #GsApp
+ * @percentage: a percentage progress (0–100 inclusive), or %GS_APP_PROGRESS_UNKNOWN
+ *
+ * This sets the progress completion of the application. Use
+ * %GS_APP_PROGRESS_UNKNOWN if the progress is unknown or has a wide confidence
+ * interval.
+ *
+ * If called more than once with the same value then subsequent calls
+ * will be ignored.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_progress (GsApp *app, guint percentage)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	if (priv->progress == percentage)
+		return;
+	if (percentage != GS_APP_PROGRESS_UNKNOWN && percentage > 100) {
+		g_warning ("cannot set %u%% for %s, setting instead: 100%%",
+			   percentage, gs_app_get_unique_id_unlocked (app));
+		percentage = 100;
+	}
+	priv->progress = percentage;
+	gs_app_queue_notify (app, obj_props[PROP_PROGRESS]);
+}
+
+/**
+ * gs_app_set_allow_cancel:
+ * @app: a #GsApp
+ * @allow_cancel: if the installation or upgrade can be cancelled or not
+ *
+ * This sets a flag indicating whether the operation can be cancelled or not.
+ * This is used by the UI to set the "Cancel" button insensitive as
+ * appropriate.
+ *
+ * Since: 3.26
+ **/
+void
+gs_app_set_allow_cancel (GsApp *app, gboolean allow_cancel)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	if (priv->allow_cancel == allow_cancel)
+		return;
+	priv->allow_cancel = allow_cancel;
+	gs_app_queue_notify (app, obj_props[PROP_CAN_CANCEL_INSTALLATION]);
+}
+
+static void
+gs_app_set_pending_action_internal (GsApp *app,
+				    GsPluginAction action)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	if (priv->pending_action == action)
+		return;
+
+	priv->pending_action = action;
+	gs_app_queue_notify (app, obj_props[PROP_PENDING_ACTION]);
+}
+
+/**
+ * gs_app_set_state:
+ * @app: a #GsApp
+ * @state: a #GsAppState, e.g. GS_APP_STATE_UPDATABLE_LIVE
+ *
+ * This sets the state of the application.
+ * The following state diagram explains the typical states.
+ * All applications start in state %GS_APP_STATE_UNKNOWN,
+ * but the frontend is not supposed to see GsApps with this state.
+ *
+ * Plugins are responsible for changing the state to one of the other
+ * states before the GsApp is passed to the frontend.
+ *
+ * |[
+ * UPDATABLE --> INSTALLING --> INSTALLED
+ * UPDATABLE --> REMOVING   --> AVAILABLE
+ * INSTALLED --> REMOVING   --> AVAILABLE
+ * AVAILABLE --> INSTALLING --> INSTALLED
+ * AVAILABLE <--> QUEUED --> INSTALLING --> INSTALLED
+ * UNKNOWN   --> UNAVAILABLE
+ * ]|
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_state (GsApp *app, GsAppState state)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	if (gs_app_set_state_internal (app, state)) {
+		/* since the state changed, and the pending-action refers to
+		 * actions that usually change the state, we assign it to the
+		 * appropriate action here */
+		GsPluginAction action = GS_PLUGIN_ACTION_UNKNOWN;
+		if (priv->state == GS_APP_STATE_QUEUED_FOR_INSTALL) {
+			if (priv->kind == AS_COMPONENT_KIND_REPOSITORY)
+				action = GS_PLUGIN_ACTION_INSTALL_REPO;
+			else
+				action = GS_PLUGIN_ACTION_INSTALL;
+		}
+		gs_app_set_pending_action_internal (app, action);
+
+		gs_app_queue_notify (app, obj_props[PROP_STATE]);
+	}
+}
+
+/**
+ * gs_app_get_kind:
+ * @app: a #GsApp
+ *
+ * Gets the kind of the application.
+ *
+ * Returns: the #AsComponentKind, e.g. %AS_COMPONENT_KIND_UNKNOWN
+ *
+ * Since: 40
+ **/
+AsComponentKind
+gs_app_get_kind (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), AS_COMPONENT_KIND_UNKNOWN);
+	return priv->kind;
+}
+
+/**
+ * gs_app_set_kind:
+ * @app: a #GsApp
+ * @kind: a #AsComponentKind, e.g. #AS_COMPONENT_KIND_DESKTOP_APP
+ *
+ * This sets the kind of the application.
+ * The following state diagram explains the typical states.
+ * All applications start with kind %AS_COMPONENT_KIND_UNKNOWN.
+ *
+ * |[
+ * PACKAGE --> NORMAL
+ * PACKAGE --> SYSTEM
+ * NORMAL  --> SYSTEM
+ * ]|
+ *
+ * Since: 40
+ **/
+void
+gs_app_set_kind (GsApp *app, AsComponentKind kind)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	gboolean state_change_ok = FALSE;
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_APP (app));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	/* same */
+	if (priv->kind == kind)
+		return;
+
+	/* trying to change */
+	if (priv->kind != AS_COMPONENT_KIND_UNKNOWN &&
+	    kind == AS_COMPONENT_KIND_UNKNOWN) {
+		g_warning ("automatically prevented from changing "
+			   "kind on %s from %s to %s!",
+			   gs_app_get_unique_id_unlocked (app),
+			   as_component_kind_to_string (priv->kind),
+			   as_component_kind_to_string (kind));
+		return;
+	}
+
+	/* check the state change is allowed */
+	switch (priv->kind) {
+	case AS_COMPONENT_KIND_UNKNOWN:
+	case AS_COMPONENT_KIND_GENERIC:
+		/* all others derive from generic */
+		state_change_ok = TRUE;
+		break;
+	case AS_COMPONENT_KIND_DESKTOP_APP:
+		/* desktop has to be reset to override */
+		if (kind == AS_COMPONENT_KIND_UNKNOWN)
+			state_change_ok = TRUE;
+		break;
+	default:
+		/* this can never change state */
+		break;
+	}
+
+	/* this state change was unexpected */
+	if (!state_change_ok) {
+		g_warning ("Kind change on %s from %s to %s is not OK",
+			   priv->id,
+			   as_component_kind_to_string (priv->kind),
+			   as_component_kind_to_string (kind));
+		return;
+	}
+
+	priv->kind = kind;
+	gs_app_queue_notify (app, obj_props[PROP_KIND]);
+
+	/* no longer valid */
+	priv->unique_id_valid = FALSE;
+}
+
+/**
+ * gs_app_get_unique_id:
+ * @app: a #GsApp
+ *
+ * Gets the unique application ID used for de-duplication.
+ *
+ * The format is "&lt;scope&gt;/&lt;kind&gt;/&lt;origin&gt;/&lt;id&gt;/&lt;branch&gt;". Any unset fields will
+ * appear as "*". This string can be used with libappstream's functions for
+ * handling data IDs, e.g.
+ * https://www.freedesktop.org/software/appstream/docs/api/appstream-as-utils.html#as-utils-data-id-valid
+ *
+ * Returns: The unique ID, e.g. `system/flatpak/flathub/org.gnome.Notes/stable`, or %NULL
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_unique_id (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	locker = g_mutex_locker_new (&priv->mutex);
+	return gs_app_get_unique_id_unlocked (app);
+}
+
+/**
+ * gs_app_set_unique_id:
+ * @app: a #GsApp
+ * @unique_id: a unique application ID, e.g. `user/fedora/\*\/gimp.desktop/\*`
+ *
+ * Sets the unique application ID used for de-duplication. See
+ * gs_app_get_unique_id() for information about the format. Normally you should
+ * not have to use this function since the unique ID can be constructed from
+ * other fields, but it can be useful for unit tests.
+ */
+void
+gs_app_set_unique_id (GsApp *app, const gchar *unique_id)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	/* check for sanity */
+	if (!as_utils_data_id_valid (unique_id))
+		g_warning ("unique_id %s not valid", unique_id);
+
+	g_free (priv->unique_id);
+	priv->unique_id = g_strdup (unique_id);
+	priv->unique_id_valid = TRUE;
+}
+
+/**
+ * gs_app_get_name:
+ * @app: a #GsApp
+ *
+ * Gets the application name.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_name (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->name;
+}
+
+/**
+ * gs_app_set_name:
+ * @app: a #GsApp
+ * @quality: A #GsAppQuality, e.g. %GS_APP_QUALITY_LOWEST
+ * @name: The short localized name, e.g. "Calculator"
+ *
+ * Sets the application name.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_name (GsApp *app, GsAppQuality quality, const gchar *name)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	/* only save this if the data is sufficiently high quality */
+	if (quality < priv->name_quality)
+		return;
+	priv->name_quality = quality;
+	if (_g_set_str (&priv->name, name))
+		gs_app_queue_notify (app, obj_props[PROP_NAME]);
+}
+
+/**
+ * gs_app_get_renamed_from:
+ * @app: a #GsApp
+ *
+ * Gets the old human-readable name of an application that's being renamed, the
+ * same name that was returned by gs_app_get_name() before the rename.
+ *
+ * Returns: (nullable): a string, or %NULL for unset
+ *
+ * Since: 40
+ **/
+const gchar *
+gs_app_get_renamed_from (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->renamed_from;
+}
+
+/**
+ * gs_app_set_renamed_from:
+ * @app: a #GsApp
+ * @renamed_from: (nullable): The old name, e.g. "Iagno"
+ *
+ * Sets the old name of an application that's being renamed
+ *
+ * Since: 40
+ **/
+void
+gs_app_set_renamed_from (GsApp *app, const gchar *renamed_from)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	_g_set_str (&priv->renamed_from, renamed_from);
+}
+
+/**
+ * gs_app_get_branch:
+ * @app: a #GsApp
+ *
+ * Gets the application branch.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_branch (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->branch;
+}
+
+/**
+ * gs_app_set_branch:
+ * @app: a #GsApp
+ * @branch: The branch, e.g. "master"
+ *
+ * Sets the application branch.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_branch (GsApp *app, const gchar *branch)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	if (_g_set_str (&priv->branch, branch))
+		priv->unique_id_valid = FALSE;
+}
+
+/**
+ * gs_app_get_source_default:
+ * @app: a #GsApp
+ *
+ * Gets the default source.
+ *
+ * Returns: a string, or %NULL
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_source_default (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	if (priv->sources->len == 0)
+		return NULL;
+	return g_ptr_array_index (priv->sources, 0);
+}
+
+/**
+ * gs_app_add_source:
+ * @app: a #GsApp
+ * @source: a source name
+ *
+ * Adds a source name for the application.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_add_source (GsApp *app, const gchar *source)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	const gchar *tmp;
+	guint i;
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (source != NULL);
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	/* check source doesn't already exist */
+	for (i = 0; i < priv->sources->len; i++) {
+		tmp = g_ptr_array_index (priv->sources, i);
+		if (g_strcmp0 (tmp, source) == 0)
+			return;
+	}
+	g_ptr_array_add (priv->sources, g_strdup (source));
+}
+
+/**
+ * gs_app_get_sources:
+ * @app: a #GsApp
+ *
+ * Gets the list of sources for the application.
+ *
+ * Returns: (element-type utf8) (transfer none): a list
+ *
+ * Since: 3.22
+ **/
+GPtrArray *
+gs_app_get_sources (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->sources;
+}
+
+/**
+ * gs_app_set_sources:
+ * @app: a #GsApp
+ * @sources: The non-localized short names, e.g. ["gnome-calculator"]
+ *
+ * This name is used for the update page if the application is collected into
+ * the 'OS Updates' group.
+ * It is typically the package names, although this should not be relied upon.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_sources (GsApp *app, GPtrArray *sources)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	_g_set_ptr_array (&priv->sources, sources);
+}
+
+/**
+ * gs_app_get_source_id_default:
+ * @app: a #GsApp
+ *
+ * Gets the default source ID.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_source_id_default (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	if (priv->source_ids->len == 0)
+		return NULL;
+	return g_ptr_array_index (priv->source_ids, 0);
+}
+
+/**
+ * gs_app_get_source_ids:
+ * @app: a #GsApp
+ *
+ * Gets the list of source IDs.
+ *
+ * Returns: (element-type utf8) (transfer none): a list
+ *
+ * Since: 3.22
+ **/
+GPtrArray *
+gs_app_get_source_ids (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->source_ids;
+}
+
+/**
+ * gs_app_clear_source_ids:
+ * @app: a #GsApp
+ *
+ * Clear the list of source IDs.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_clear_source_ids (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	g_ptr_array_set_size (priv->source_ids, 0);
+}
+
+/**
+ * gs_app_set_source_ids:
+ * @app: a #GsApp
+ * @source_ids: The source-id, e.g. ["gnome-calculator;0.134;fedora"]
+ *		or ["/home/hughsie/.local/share/applications/0ad.desktop"]
+ *
+ * This ID is used internally to the controlling plugin.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_source_ids (GsApp *app, GPtrArray *source_ids)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	_g_set_ptr_array (&priv->source_ids, source_ids);
+}
+
+/**
+ * gs_app_add_source_id:
+ * @app: a #GsApp
+ * @source_id: a source ID, e.g. "gnome-calculator;0.134;fedora"
+ *
+ * Adds a source ID to the application.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_add_source_id (GsApp *app, const gchar *source_id)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	const gchar *tmp;
+	guint i;
+
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (source_id != NULL);
+
+	/* only add if not already present */
+	for (i = 0; i < priv->source_ids->len; i++) {
+		tmp = g_ptr_array_index (priv->source_ids, i);
+		if (g_strcmp0 (tmp, source_id) == 0)
+			return;
+	}
+	g_ptr_array_add (priv->source_ids, g_strdup (source_id));
+}
+
+/**
+ * gs_app_get_project_group:
+ * @app: a #GsApp
+ *
+ * Gets a project group for the application.
+ * Applications belonging to other project groups may not be shown in
+ * this software center.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_project_group (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->project_group;
+}
+
+/**
+ * gs_app_get_developer_name:
+ * @app: a #GsApp
+ *
+ * Gets the developer name for the application.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_developer_name (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->developer_name;
+}
+
+/**
+ * gs_app_set_project_group:
+ * @app: a #GsApp
+ * @project_group: The non-localized project group, e.g. "GNOME" or "KDE"
+ *
+ * Sets a project group for the application.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_project_group (GsApp *app, const gchar *project_group)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	_g_set_str (&priv->project_group, project_group);
+}
+
+/**
+ * gs_app_set_developer_name:
+ * @app: a #GsApp
+ * @developer_name: The developer name, e.g. "Richard Hughes"
+ *
+ * Sets a developer name for the application.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_developer_name (GsApp *app, const gchar *developer_name)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	_g_set_str (&priv->developer_name, developer_name);
+}
+
+/**
+ * gs_app_get_icon_for_size:
+ * @app: a #GsApp
+ * @size: size (width or height, square) of the icon to fetch, in device pixels
+ * @scale: scale of the icon to fetch, typically from gtk_widget_get_scale_factor()
+ * @fallback_icon_name: (nullable): name of an icon to load as a fallback if
+ *    no other suitable one is found, or %NULL for no fallback
+ *
+ * Finds the most appropriate icon in the @app’s set of icons to be loaded at
+ * the given @size×@scale to represent the application. This might be provided
+ * by the backend at the given @size, or downsized from a larger icon provided
+ * by the backend. The return value is guaranteed to be suitable for loading as
+ * a pixbuf at @size, if it’s not %NULL.
+ *
+ * If an image at least @size pixels in width isn’t available, and
+ * @fallback_icon_name has not been provided, %NULL will be returned. If
+ * @fallback_icon_name has been provided, a #GIcon representing that will be
+ * returned, and %NULL is guaranteed not to be returned.
+ *
+ * Icons which come from a remote server (over HTTP or HTTPS) will be returned
+ * as a pointer into a local cache, which may not have been populated. You must
+ * call gs_remote_icon_ensure_cached() on icons of type #GsRemoteIcon to
+ * download them; this function will not do that for you.
+ *
+ * This function may do disk I/O or image resizing, but it will not do network
+ * I/O to load a pixbuf. It should be acceptable to call this from a UI thread.
+ *
+ * Returns: (transfer full) (nullable): a #GIcon, or %NULL
+ *
+ * Since: 40
+ */
+GIcon *
+gs_app_get_icon_for_size (GsApp       *app,
+                          guint        size,
+                          guint        scale,
+                          const gchar *fallback_icon_name)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	g_return_val_if_fail (size > 0, NULL);
+	g_return_val_if_fail (scale >= 1, NULL);
+
+	g_debug ("Looking for icon for %s, at size %u×%u, with fallback %s",
+		 gs_app_get_id (app), size, scale, fallback_icon_name);
+
+	/* See if there’s an icon the right size, or the first one which is too
+	 * big which could be scaled down. Note that the icons array may be
+	 * lazily created. */
+	for (guint i = 0; priv->icons != NULL && i < priv->icons->len; i++) {
+		GIcon *icon = priv->icons->pdata[i];
+		g_autofree gchar *icon_str = g_icon_to_string (icon);
+		guint icon_width = gs_icon_get_width (icon);
+		guint icon_height = gs_icon_get_height (icon);
+		guint icon_scale = gs_icon_get_scale (icon);
+
+		g_debug ("\tConsidering icon of type %s (%s), width %u×%u",
+			 G_OBJECT_TYPE_NAME (icon), icon_str, icon_width, icon_scale);
+
+		/* Appstream only guarantees the 64x64@1 cached icon is present, ignore other icons that aren't installed. */
+		if (G_IS_FILE_ICON (icon) && !(icon_width == 64 && icon_height == 64 && icon_scale == 1)) {
+			GFile *file = g_file_icon_get_file (G_FILE_ICON (icon));
+			if (!g_file_query_exists (file, NULL)) {
+				continue;
+			}
+		}
+
+		/* Ignore icons with unknown width and skip over ones which
+		 * are too small. */
+		if (icon_width == 0 || icon_width * icon_scale < size * scale)
+			continue;
+
+		if (icon_width * icon_scale >= size * scale)
+			return g_object_ref (icon);
+	}
+
+	g_debug ("Found no icons of the right size; checking themed icons");
+
+	/* If there’s a themed icon with no width set, use that, as typically
+	 * themed icons are available in all the right sizes. */
+	for (guint i = 0; priv->icons != NULL && i < priv->icons->len; i++) {
+		GIcon *icon = priv->icons->pdata[i];
+		guint icon_width = gs_icon_get_width (icon);
+
+		if (icon_width == 0 && G_IS_THEMED_ICON (icon))
+			return g_object_ref (icon);
+	}
+
+	if (scale > 1) {
+		g_debug ("Retrying at scale 1");
+		return gs_app_get_icon_for_size (app, size, 1, fallback_icon_name);
+	} else if (fallback_icon_name != NULL) {
+		g_debug ("Using fallback icon %s", fallback_icon_name);
+		return g_themed_icon_new (fallback_icon_name);
+	} else {
+		g_debug ("No icon found");
+		return NULL;
+	}
+}
+
+/**
+ * gs_app_get_action_screenshot:
+ * @app: a #GsApp
+ *
+ * Gets a screenshot for the pending user action.
+ *
+ * Returns: (transfer none) (nullable): a #AsScreenshot, or %NULL
+ *
+ * Since: 40
+ **/
+AsScreenshot *
+gs_app_get_action_screenshot (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->action_screenshot;
+}
+
+/**
+ * gs_app_get_icons:
+ * @app: a #GsApp
+ *
+ * Gets the icons for the application.
+ *
+ * This will never return an empty array; it will always return either %NULL or
+ * a non-empty array.
+ *
+ * Returns: (transfer none) (element-type GIcon) (nullable): an array of icons,
+ *     or %NULL if there are no icons
+ *
+ * Since: 3.22
+ **/
+GPtrArray *
+gs_app_get_icons (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+
+	if (priv->icons != NULL && priv->icons->len == 0)
+		return NULL;
+
+	return priv->icons;
+}
+
+static gint
+icon_sort_width_cb (gconstpointer a,
+                    gconstpointer b)
+{
+	GIcon *icon_a = *((GIcon **) a);
+	GIcon *icon_b = *((GIcon **) b);
+	guint width_a = gs_icon_get_width (icon_a);
+	guint width_b = gs_icon_get_width (icon_b);
+
+	/* Sort unknown widths (0 value) to the end. */
+	if (width_a == 0 && width_b == 0)
+		return 0;
+	else if (width_a == 0)
+		return 1;
+	else if (width_b == 0)
+		return -1;
+	else
+		return width_a - width_b;
+}
+
+/**
+ * gs_app_add_icon:
+ * @app: a #GsApp
+ * @icon: a #GIcon
+ *
+ * Adds an icon to use for the application.
+ * If the first icon added cannot be loaded then the next one is tried.
+ *
+ * Since: 40
+ **/
+void
+gs_app_add_icon (GsApp *app, GIcon *icon)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (G_IS_ICON (icon));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	if (priv->icons == NULL)
+		priv->icons = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);
+
+	g_ptr_array_add (priv->icons, g_object_ref (icon));
+
+	/* Ensure the array is sorted by increasing width. */
+	g_ptr_array_sort (priv->icons, icon_sort_width_cb);
+}
+
+/**
+ * gs_app_remove_all_icons:
+ * @app: a #GsApp
+ *
+ * Remove all icons from @app.
+ *
+ * Since: 40
+ */
+void
+gs_app_remove_all_icons (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	if (priv->icons != NULL)
+		g_ptr_array_set_size (priv->icons, 0);
+}
+
+/**
+ * gs_app_get_agreement:
+ * @app: a #GsApp
+ *
+ * Gets the agreement text for the application.
+ *
+ * Returns: a string in AppStream description format, or %NULL for unset
+ *
+ * Since: 3.28
+ **/
+const gchar *
+gs_app_get_agreement (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->agreement;
+}
+
+/**
+ * gs_app_set_agreement:
+ * @app: a #GsApp
+ * @agreement: The agreement text, e.g. "<p>Foobar</p>"
+ *
+ * Sets the application end-user agreement (e.g. a EULA) in AppStream
+ * description format.
+ *
+ * Since: 3.28
+ **/
+void
+gs_app_set_agreement (GsApp *app, const gchar *agreement)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	_g_set_str (&priv->agreement, agreement);
+}
+
+/**
+ * gs_app_get_local_file:
+ * @app: a #GsApp
+ *
+ * Gets the file that backs this application, for instance this might
+ * be a local file in ~/Downloads that we are installing.
+ *
+ * Returns: (transfer none): a #GFile, or %NULL
+ *
+ * Since: 3.22
+ **/
+GFile *
+gs_app_get_local_file (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->local_file;
+}
+
+/**
+ * gs_app_set_local_file:
+ * @app: a #GsApp
+ * @local_file: a #GFile, or %NULL
+ *
+ * Sets the file that backs this application, for instance this might
+ * be a local file in ~/Downloads that we are installing.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_local_file (GsApp *app, GFile *local_file)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	g_set_object (&priv->local_file, local_file);
+}
+
+/**
+ * gs_app_dup_content_rating:
+ * @app: a #GsApp
+ *
+ * Gets the content rating for this application.
+ *
+ * Returns: (transfer full) (nullable): a #AsContentRating, or %NULL
+ *
+ * Since: 41
+ **/
+AsContentRating *
+gs_app_dup_content_rating (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	locker = g_mutex_locker_new (&priv->mutex);
+	return (priv->content_rating != NULL) ? g_object_ref (priv->content_rating) : NULL;
+}
+
+/**
+ * gs_app_set_content_rating:
+ * @app: a #GsApp
+ * @content_rating: a #AsContentRating, or %NULL
+ *
+ * Sets the content rating for this application.
+ *
+ * Since: 40
+ **/
+void
+gs_app_set_content_rating (GsApp *app, AsContentRating *content_rating)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	if (g_set_object (&priv->content_rating, content_rating))
+		gs_app_queue_notify (app, obj_props[PROP_CONTENT_RATING]);
+}
+
+/**
+ * gs_app_get_runtime:
+ * @app: a #GsApp
+ *
+ * Gets the runtime for the installed application.
+ *
+ * Returns: (transfer none): a #GsApp, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+GsApp *
+gs_app_get_runtime (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->runtime;
+}
+
+/**
+ * gs_app_set_runtime:
+ * @app: a #GsApp
+ * @runtime: a #GsApp
+ *
+ * Sets the runtime that the installed application requires.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_runtime (GsApp *app, GsApp *runtime)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (GS_IS_APP (runtime));
+	g_return_if_fail (app != runtime);
+	locker = g_mutex_locker_new (&priv->mutex);
+	g_set_object (&priv->runtime, runtime);
+
+	/* The runtime adds to the main app’s sizes. */
+	gs_app_queue_notify (app, obj_props[PROP_SIZE_DOWNLOAD_DEPENDENCIES_TYPE]);
+	gs_app_queue_notify (app, obj_props[PROP_SIZE_DOWNLOAD_DEPENDENCIES]);
+}
+
+/**
+ * gs_app_set_action_screenshot:
+ * @app: a #GsApp
+ * @action_screenshot: (transfer none) (nullable): a #AsScreenshot, or %NULL
+ *
+ * Sets a screenshot used to represent the action.
+ *
+ * Since: 40
+ **/
+void
+gs_app_set_action_screenshot (GsApp *app, AsScreenshot *action_screenshot)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	g_set_object (&priv->action_screenshot, action_screenshot);
+}
+
+typedef enum {
+	GS_APP_VERSION_FIXUP_RELEASE		= 1,
+	GS_APP_VERSION_FIXUP_DISTRO_SUFFIX	= 2,
+	GS_APP_VERSION_FIXUP_GIT_SUFFIX		= 4,
+	GS_APP_VERSION_FIXUP_LAST,
+} GsAppVersionFixup;
+
+/**
+ * gs_app_get_ui_version:
+ *
+ * convert 1:1.6.2-7.fc17 into "Version 1.6.2"
+ **/
+static gchar *
+gs_app_get_ui_version (const gchar *version, guint64 flags)
+{
+	guint i;
+	gchar *new;
+	gchar *f;
+
+	/* nothing set */
+	if (version == NULL)
+		return NULL;
+
+	/* first remove any epoch */
+	for (i = 0; version[i] != '\0'; i++) {
+		if (version[i] == ':') {
+			version = &version[i+1];
+			break;
+		}
+		if (!g_ascii_isdigit (version[i]))
+			break;
+	}
+
+	/* then remove any distro suffix */
+	new = g_strdup (version);
+	if ((flags & GS_APP_VERSION_FIXUP_DISTRO_SUFFIX) > 0) {
+		f = g_strstr_len (new, -1, ".fc");
+		if (f != NULL)
+			*f= '\0';
+		f = g_strstr_len (new, -1, ".el");
+		if (f != NULL)
+			*f= '\0';
+	}
+
+	/* then remove any release */
+	if ((flags & GS_APP_VERSION_FIXUP_RELEASE) > 0) {
+		f = g_strrstr_len (new, -1, "-");
+		if (f != NULL)
+			*f= '\0';
+	}
+
+	/* then remove any git suffix */
+	if ((flags & GS_APP_VERSION_FIXUP_GIT_SUFFIX) > 0) {
+		f = g_strrstr_len (new, -1, ".2012");
+		if (f != NULL)
+			*f= '\0';
+		f = g_strrstr_len (new, -1, ".2013");
+		if (f != NULL)
+			*f= '\0';
+	}
+
+	return new;
+}
+
+static void
+gs_app_ui_versions_invalidate (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_free (priv->version_ui);
+	g_free (priv->update_version_ui);
+	priv->version_ui = NULL;
+	priv->update_version_ui = NULL;
+}
+
+static void
+gs_app_ui_versions_populate (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	guint i;
+	guint64 flags[] = { GS_APP_VERSION_FIXUP_RELEASE |
+			    GS_APP_VERSION_FIXUP_DISTRO_SUFFIX |
+			    GS_APP_VERSION_FIXUP_GIT_SUFFIX,
+			    GS_APP_VERSION_FIXUP_DISTRO_SUFFIX |
+			    GS_APP_VERSION_FIXUP_GIT_SUFFIX,
+			    GS_APP_VERSION_FIXUP_DISTRO_SUFFIX,
+			    0 };
+
+	/* try each set of bitfields in order */
+	for (i = 0; flags[i] != 0; i++) {
+		priv->version_ui = gs_app_get_ui_version (priv->version, flags[i]);
+		priv->update_version_ui = gs_app_get_ui_version (priv->update_version, flags[i]);
+		if (g_strcmp0 (priv->version_ui, priv->update_version_ui) != 0) {
+			gs_app_queue_notify (app, obj_props[PROP_VERSION]);
+			return;
+		}
+		gs_app_ui_versions_invalidate (app);
+	}
+
+	/* we tried, but failed */
+	priv->version_ui = g_strdup (priv->version);
+	priv->update_version_ui = g_strdup (priv->update_version);
+}
+
+/**
+ * gs_app_get_version:
+ * @app: a #GsApp
+ *
+ * Gets the exact version for the application.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_version (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->version;
+}
+
+/**
+ * gs_app_get_version_ui:
+ * @app: a #GsApp
+ *
+ * Gets a version string that can be displayed in a UI.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_version_ui (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+
+	/* work out the two version numbers */
+	if (priv->version != NULL &&
+	    priv->version_ui == NULL) {
+		gs_app_ui_versions_populate (app);
+	}
+
+	return priv->version_ui;
+}
+
+/**
+ * gs_app_set_version:
+ * @app: a #GsApp
+ * @version: The version, e.g. "2:1.2.3.fc19"
+ *
+ * This saves the version after stripping out any non-friendly parts, such as
+ * distro tags, git revisions and that kind of thing.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_version (GsApp *app, const gchar *version)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	if (_g_set_str (&priv->version, version)) {
+		gs_app_ui_versions_invalidate (app);
+		gs_app_queue_notify (app, obj_props[PROP_VERSION]);
+	}
+}
+
+/**
+ * gs_app_get_summary:
+ * @app: a #GsApp
+ *
+ * Gets the single-line description of the application.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_summary (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->summary;
+}
+
+/**
+ * gs_app_set_summary:
+ * @app: a #GsApp
+ * @quality: a #GsAppQuality, e.g. %GS_APP_QUALITY_LOWEST
+ * @summary: a string, e.g. "A graphical calculator for GNOME"
+ *
+ * The medium length one-line localized name.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_summary (GsApp *app, GsAppQuality quality, const gchar *summary)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	/* only save this if the data is sufficiently high quality */
+	if (quality < priv->summary_quality)
+		return;
+	priv->summary_quality = quality;
+	if (_g_set_str (&priv->summary, summary))
+		gs_app_queue_notify (app, obj_props[PROP_SUMMARY]);
+}
+
+/**
+ * gs_app_get_description:
+ * @app: a #GsApp
+ *
+ * Gets the long multi-line description of the application.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_description (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->description;
+}
+
+/**
+ * gs_app_set_description:
+ * @app: a #GsApp
+ * @quality: a #GsAppQuality, e.g. %GS_APP_QUALITY_LOWEST
+ * @description: a string, e.g. "GNOME Calculator is a graphical calculator for GNOME..."
+ *
+ * Sets the long multi-line description of the application.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_description (GsApp *app, GsAppQuality quality, const gchar *description)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	/* only save this if the data is sufficiently high quality */
+	if (quality < priv->description_quality)
+		return;
+	priv->description_quality = quality;
+	_g_set_str (&priv->description, description);
+}
+
+/**
+ * gs_app_get_url:
+ * @app: a #GsApp
+ * @kind: a #AsUrlKind, e.g. %AS_URL_KIND_HOMEPAGE
+ *
+ * Gets a web address of a specific type.
+ *
+ * Returns: (nullable): a string, or %NULL for unset
+ *
+ * Since: 40
+ **/
+const gchar *
+gs_app_get_url (GsApp *app, AsUrlKind kind)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	if (priv->urls == NULL)
+		return NULL;
+	return g_hash_table_lookup (priv->urls, GINT_TO_POINTER (kind));
+}
+
+/**
+ * gs_app_set_url:
+ * @app: a #GsApp
+ * @kind: a #AsUrlKind, e.g. %AS_URL_KIND_HOMEPAGE
+ * @url: a web URL, e.g. "http://www.hughsie.com/"
+ *
+ * Sets a web address of a specific type.
+ *
+ * Since: 40
+ **/
+void
+gs_app_set_url (GsApp *app, AsUrlKind kind, const gchar *url)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	if (priv->urls == NULL)
+		priv->urls = g_hash_table_new_full (g_direct_hash, g_direct_equal,
+						    NULL, g_free);
+
+	g_hash_table_insert (priv->urls,
+			     GINT_TO_POINTER (kind),
+			     g_strdup (url));
+
+	gs_app_queue_notify (app, obj_props[PROP_URLS]);
+}
+
+/**
+ * gs_app_get_url_missing:
+ * @app: a #GsApp
+ *
+ * Gets a web address for the application with explanations
+ * why it does not have an installation candidate.
+ *
+ * Returns: (nullable): a string, or %NULL for unset
+ *
+ * Since: 40
+ **/
+const gchar *
+gs_app_get_url_missing (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	locker = g_mutex_locker_new (&priv->mutex);
+	return priv->url_missing;
+}
+
+/**
+ * gs_app_set_url_missing:
+ * @app: a #GsApp
+ * @url: (nullable): a web URL, e.g. `http://www.packagekit.org/pk-package-not-found.html`, or %NULL
+ *
+ * Sets a web address containing explanations why this app
+ * does not have an installation candidate.
+ *
+ * Since: 40
+ **/
+void
+gs_app_set_url_missing (GsApp *app, const gchar *url)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	if (g_strcmp0 (priv->url_missing, url) == 0)
+		return;
+	g_free (priv->url_missing);
+	priv->url_missing = g_strdup (url);
+	gs_app_queue_notify (app, obj_props[PROP_URL_MISSING]);
+}
+
+/**
+ * gs_app_get_launchable:
+ * @app: a #GsApp
+ * @kind: a #AsLaunchableKind, e.g. %AS_LAUNCHABLE_KIND_DESKTOP_ID
+ *
+ * Gets a launchable of a specific type.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 40
+ **/
+const gchar *
+gs_app_get_launchable (GsApp *app, AsLaunchableKind kind)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	locker = g_mutex_locker_new (&priv->mutex);
+	return g_hash_table_lookup (priv->launchables,
+				    as_launchable_kind_to_string (kind));
+}
+
+/**
+ * gs_app_set_launchable:
+ * @app: a #GsApp
+ * @kind: a #AsLaunchableKind, e.g. %AS_LAUNCHABLE_KIND_DESKTOP_ID
+ * @launchable: a way to launch, e.g. "org.gnome.Sysprof2.desktop"
+ *
+ * Sets a launchable of a specific type.
+ *
+ * Since: 40
+ **/
+void
+gs_app_set_launchable (GsApp *app, AsLaunchableKind kind, const gchar *launchable)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	gpointer current_value = NULL;
+	const gchar *key;
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	key = as_launchable_kind_to_string (kind);
+	if (g_hash_table_lookup_extended (priv->launchables, key, NULL, &current_value)) {
+		if (g_strcmp0 ((const gchar *) current_value, launchable) != 0)
+			g_debug ("Preventing app '%s' replace of %s's launchable '%s' with '%s'",
+				 priv->name, key, (const gchar *) current_value, launchable);
+	} else {
+		g_hash_table_insert (priv->launchables,
+				     (gpointer) as_launchable_kind_to_string (kind),
+				     g_strdup (launchable));
+	}
+}
+
+/**
+ * gs_app_get_license:
+ * @app: a #GsApp
+ *
+ * Gets the project license of the application.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_license (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->license;
+}
+
+/**
+ * gs_app_get_license_is_free:
+ * @app: a #GsApp
+ *
+ * Returns if the application is free software.
+ *
+ * Returns: %TRUE if the application is free software
+ *
+ * Since: 3.22
+ **/
+gboolean
+gs_app_get_license_is_free (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+	return priv->license_is_free;
+}
+
+/**
+ * gs_app_set_license:
+ * @app: a #GsApp
+ * @quality: a #GsAppQuality, e.g. %GS_APP_QUALITY_NORMAL
+ * @license: a SPDX license string, e.g. "GPL-3.0 AND LGPL-2.0+"
+ *
+ * Sets the project licenses used in the application.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_license (GsApp *app, GsAppQuality quality, const gchar *license)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_APP (app));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	/* only save this if the data is sufficiently high quality */
+	if (quality <= priv->license_quality)
+		return;
+	if (license == NULL)
+		return;
+	priv->license_quality = quality;
+
+	priv->license_is_free = as_license_is_free_license (license);
+
+	if (_g_set_str (&priv->license, license))
+		gs_app_queue_notify (app, obj_props[PROP_LICENSE]);
+}
+
+/**
+ * gs_app_get_summary_missing:
+ * @app: a #GsApp
+ *
+ * Gets the one-line summary to use when this application is missing.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_summary_missing (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->summary_missing;
+}
+
+/**
+ * gs_app_set_summary_missing:
+ * @app: a #GsApp
+ * @summary_missing: a string, or %NULL
+ *
+ * Sets the one-line summary to use when this application is missing.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_summary_missing (GsApp *app, const gchar *summary_missing)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	_g_set_str (&priv->summary_missing, summary_missing);
+}
+
+static gboolean
+_gs_app_has_desktop_group (GsApp *app, const gchar *desktop_group)
+{
+	guint i;
+	g_auto(GStrv) split = g_strsplit (desktop_group, "::", -1);
+	for (i = 0; split[i] != NULL; i++) {
+		if (!gs_app_has_category (app, split[i]))
+			return FALSE;
+	}
+	return TRUE;
+}
+
+/**
+ * gs_app_get_menu_path:
+ * @app: a #GsApp
+ *
+ * Returns the menu path which is an array of path elements.
+ * The resulting array is an internal structure and must not be
+ * modified or freed.
+ *
+ * Returns: a %NULL-terminated array of strings
+ *
+ * Since: 3.22
+ **/
+gchar **
+gs_app_get_menu_path (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+
+	/* Lazy load. */
+	if (priv->menu_path == NULL) {
+		const gchar *strv[] = { "", NULL, NULL };
+		const GsDesktopData *msdata;
+		gboolean found = FALSE;
+
+		/* find a top level category the app has */
+		msdata = gs_desktop_get_data ();
+		for (gsize i = 0; !found && msdata[i].id != NULL; i++) {
+			const GsDesktopData *data = &msdata[i];
+			for (gsize j = 0; !found && data->mapping[j].id != NULL; j++) {
+				const GsDesktopMap *map = &data->mapping[j];
+				g_autofree gchar *msgctxt = NULL;
+
+				if (g_strcmp0 (map->id, "all") == 0)
+					continue;
+				if (g_strcmp0 (map->id, "featured") == 0)
+					continue;
+				msgctxt = g_strdup_printf ("Menu of %s", data->name);
+				for (gsize k = 0; !found && map->fdo_cats[k] != NULL; k++) {
+					const gchar *tmp = msdata[i].mapping[j].fdo_cats[k];
+					if (_gs_app_has_desktop_group (app, tmp)) {
+						strv[0] = g_dgettext (GETTEXT_PACKAGE, msdata[i].name);
+						strv[1] = g_dpgettext2 (GETTEXT_PACKAGE, msgctxt,
+							                msdata[i].mapping[j].name);
+						found = TRUE;
+						break;
+					}
+				}
+			}
+		}
+
+		/* always set something to avoid keep searching for this */
+		gs_app_set_menu_path (app, (gchar **) strv);
+	}
+
+	return priv->menu_path;
+}
+
+/**
+ * gs_app_set_menu_path:
+ * @app: a #GsApp
+ * @menu_path: a %NULL-terminated array of strings
+ *
+ * Sets the new menu path. The menu path is an array of path elements.
+ * This function creates a deep copy of the path.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_menu_path (GsApp *app, gchar **menu_path)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	_g_set_strv (&priv->menu_path, menu_path);
+}
+
+/**
+ * gs_app_get_origin:
+ * @app: a #GsApp
+ *
+ * Gets the origin for the application, e.g. "fedora".
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_origin (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->origin;
+}
+
+/**
+ * gs_app_set_origin:
+ * @app: a #GsApp
+ * @origin: a string, or %NULL
+ *
+ * The origin is the original source of the application e.g. "fedora-updates"
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_origin (GsApp *app, const gchar *origin)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	/* same */
+	if (g_strcmp0 (origin, priv->origin) == 0)
+		return;
+
+	/* trying to change */
+	if (priv->origin != NULL && origin != NULL) {
+		g_warning ("automatically prevented from changing "
+			   "origin on %s from %s to %s!",
+			   gs_app_get_unique_id_unlocked (app),
+			   priv->origin, origin);
+		return;
+	}
+
+	g_free (priv->origin);
+	priv->origin = g_strdup (origin);
+
+	/* no longer valid */
+	priv->unique_id_valid = FALSE;
+}
+
+/**
+ * gs_app_get_origin_appstream:
+ * @app: a #GsApp
+ *
+ * Gets the appstream origin for the application, e.g. "fedora".
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.28
+ **/
+const gchar *
+gs_app_get_origin_appstream (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->origin_appstream;
+}
+
+/**
+ * gs_app_set_origin_appstream:
+ * @app: a #GsApp
+ * @origin_appstream: a string, or %NULL
+ *
+ * The appstream origin is the appstream source of the application e.g. "fedora"
+ *
+ * Since: 3.28
+ **/
+void
+gs_app_set_origin_appstream (GsApp *app, const gchar *origin_appstream)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	/* same */
+	if (g_strcmp0 (origin_appstream, priv->origin_appstream) == 0)
+		return;
+
+	g_free (priv->origin_appstream);
+	priv->origin_appstream = g_strdup (origin_appstream);
+}
+
+/**
+ * gs_app_get_origin_hostname:
+ * @app: a #GsApp
+ *
+ * Gets the hostname of the origin used to install the application, e.g.
+ * "fedoraproject.org" or "sdk.gnome.org".
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_origin_hostname (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->origin_hostname;
+}
+
+/**
+ * gs_app_set_origin_hostname:
+ * @app: a #GsApp
+ * @origin_hostname: a string, or %NULL
+ *
+ * The origin is the hostname of the source used to install the application
+ * e.g. "fedoraproject.org"
+ *
+ * You can also use a full URL as @origin_hostname and this will be parsed and
+ * the hostname extracted. This process will also remove any unnecessary DNS
+ * prefixes like "download" or "mirrors".
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_origin_hostname (GsApp *app, const gchar *origin_hostname)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_autoptr(GUri) uri = NULL;
+	guint i;
+	const gchar *prefixes[] = { "download.", "mirrors.", NULL };
+
+	g_return_if_fail (GS_IS_APP (app));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	/* same */
+	if (g_strcmp0 (origin_hostname, priv->origin_hostname) == 0)
+		return;
+	g_free (priv->origin_hostname);
+
+	/* convert a URL */
+	uri = g_uri_parse (origin_hostname, SOUP_HTTP_URI_FLAGS, NULL);
+	if (uri != NULL)
+		origin_hostname = g_uri_get_host (uri);
+
+	/* remove some common prefixes */
+	for (i = 0; prefixes[i] != NULL; i++) {
+		if (g_str_has_prefix (origin_hostname, prefixes[i]))
+			origin_hostname += strlen (prefixes[i]);
+	}
+
+	/* fallback for localhost */
+	if (g_strcmp0 (origin_hostname, "") == 0)
+		origin_hostname = "localhost";
+
+	/* success */
+	priv->origin_hostname = g_strdup (origin_hostname);
+}
+
+/**
+ * gs_app_add_screenshot:
+ * @app: a #GsApp
+ * @screenshot: a #AsScreenshot
+ *
+ * Adds a screenshot to the application.
+ *
+ * Since: 40
+ **/
+void
+gs_app_add_screenshot (GsApp *app, AsScreenshot *screenshot)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (AS_IS_SCREENSHOT (screenshot));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+	g_ptr_array_add (priv->screenshots, g_object_ref (screenshot));
+}
+
+/**
+ * gs_app_get_screenshots:
+ * @app: a #GsApp
+ *
+ * Gets the list of screenshots.
+ *
+ * Returns: (element-type AsScreenshot) (transfer none): a list
+ *
+ * Since: 3.22
+ **/
+GPtrArray *
+gs_app_get_screenshots (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->screenshots;
+}
+
+/**
+ * gs_app_get_update_version:
+ * @app: a #GsApp
+ *
+ * Gets the newest update version.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_update_version (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->update_version;
+}
+
+/**
+ * gs_app_get_update_version_ui:
+ * @app: a #GsApp
+ *
+ * Gets the update version for the UI.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_update_version_ui (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+
+	/* work out the two version numbers */
+	if (priv->update_version != NULL &&
+	    priv->update_version_ui == NULL) {
+		gs_app_ui_versions_populate (app);
+	}
+
+	return priv->update_version_ui;
+}
+
+static void
+gs_app_set_update_version_internal (GsApp *app, const gchar *update_version)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	if (_g_set_str (&priv->update_version, update_version))
+		gs_app_ui_versions_invalidate (app);
+}
+
+/**
+ * gs_app_set_update_version:
+ * @app: a #GsApp
+ * @update_version: a string, e.g. "0.1.2.3"
+ *
+ * Sets the new version number of the update.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_update_version (GsApp *app, const gchar *update_version)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	gs_app_set_update_version_internal (app, update_version);
+	gs_app_queue_notify (app, obj_props[PROP_VERSION]);
+}
+
+/**
+ * gs_app_get_update_details_markup:
+ * @app: a #GsApp
+ *
+ * Gets the multi-line description for the update as a Pango markup.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 42.0
+ **/
+const gchar *
+gs_app_get_update_details_markup (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->update_details_markup;
+}
+
+/**
+ * gs_app_set_update_details_markup:
+ * @app: a #GsApp
+ * @markup: a Pango markup
+ *
+ * Sets the multi-line description for the update as markup.
+ *
+ * See: gs_app_set_update_details_text()
+ *
+ * Since: 42.0
+ **/
+void
+gs_app_set_update_details_markup (GsApp *app,
+				  const gchar *markup)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	_g_set_str (&priv->update_details_markup, markup);
+}
+
+/**
+ * gs_app_set_update_details_text:
+ * @app: a #GsApp
+ * @text: a text without Pango markup
+ *
+ * Sets the multi-line description for the update as text,
+ * escaping the @text to be safe for a Pango markup.
+ *
+ * See: gs_app_set_update_details_markup()
+ *
+ * Since: 42.0
+ **/
+void
+gs_app_set_update_details_text (GsApp *app,
+				const gchar *text)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	if (text == NULL) {
+		_g_set_str (&priv->update_details_markup, NULL);
+	} else {
+		gchar *markup = g_markup_escape_text (text, -1);
+		g_free (priv->update_details_markup);
+		priv->update_details_markup = markup;
+	}
+}
+
+/**
+ * gs_app_get_update_urgency:
+ * @app: a #GsApp
+ *
+ * Gets the update urgency.
+ *
+ * Returns: a #AsUrgencyKind, or %AS_URGENCY_KIND_UNKNOWN for unset
+ *
+ * Since: 40
+ **/
+AsUrgencyKind
+gs_app_get_update_urgency (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), AS_URGENCY_KIND_UNKNOWN);
+	return priv->update_urgency;
+}
+
+/**
+ * gs_app_set_update_urgency:
+ * @app: a #GsApp
+ * @update_urgency: a #AsUrgencyKind
+ *
+ * Sets the update urgency.
+ *
+ * Since: 40
+ **/
+void
+gs_app_set_update_urgency (GsApp *app, AsUrgencyKind update_urgency)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_if_fail (GS_IS_APP (app));
+	if (update_urgency == priv->update_urgency)
+		return;
+	priv->update_urgency = update_urgency;
+}
+
+/**
+ * gs_app_dup_management_plugin:
+ * @app: a #GsApp
+ *
+ * Gets the management plugin.
+ *
+ * This is some metadata about the application which gives which plugin should
+ * handle the install, remove or upgrade actions.
+ *
+ * Returns: (nullable) (transfer full): the management plugin, or %NULL for unset
+ *
+ * Since: 42
+ **/
+GsPlugin *
+gs_app_dup_management_plugin (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return g_weak_ref_get (&priv->management_plugin_weak);
+}
+
+/**
+ * gs_app_has_management_plugin:
+ * @app: a #GsApp
+ * @plugin: (nullable) (transfer none): a #GsPlugin to check against, or %NULL
+ *
+ * Check whether the management plugin for @app is set to @plugin.
+ *
+ * If @plugin is %NULL, %TRUE is returned only if the @app has no management
+ * plugin set.
+ *
+ * Returns: %TRUE if @plugin is the management plugin for @app, %FALSE otherwise
+ * Since: 42
+ */
+gboolean
+gs_app_has_management_plugin (GsApp    *app,
+                              GsPlugin *plugin)
+{
+	g_autoptr(GsPlugin) app_plugin = gs_app_dup_management_plugin (app);
+	return (app_plugin == plugin);
+}
+
+/**
+ * gs_app_set_management_plugin:
+ * @app: a #GsApp
+ * @management_plugin: (nullable) (transfer none): a plugin, or %NULL
+ *
+ * The management plugin is the plugin that can handle doing install and remove
+ * operations on the #GsApp.
+ *
+ * It is an error to attempt to change the management plugin once it has been
+ * previously set or to try to use this function on a wildcard application.
+ *
+ * Since: 42
+ **/
+void
+gs_app_set_management_plugin (GsApp    *app,
+                              GsPlugin *management_plugin)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_autoptr(GsPlugin) old_plugin = NULL;
+
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (management_plugin == NULL || GS_IS_PLUGIN (management_plugin));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	/* plugins cannot adopt wildcard packages */
+	if (gs_app_has_quirk (app, GS_APP_QUIRK_IS_WILDCARD)) {
+		g_warning ("plugins should not set the management plugin on "
+			   "%s to %s -- create a new GsApp in refine()!",
+			   gs_app_get_unique_id_unlocked (app),
+			   (management_plugin != NULL) ? gs_plugin_get_name (management_plugin) : "(null)");
+		return;
+	}
+
+	/* same */
+	old_plugin = g_weak_ref_get (&priv->management_plugin_weak);
+
+	if (old_plugin == management_plugin)
+		return;
+
+	/* trying to change */
+	if (old_plugin != NULL && management_plugin != NULL) {
+		g_warning ("automatically prevented from changing "
+			   "management plugin on %s from %s to %s!",
+			   gs_app_get_unique_id_unlocked (app),
+			   gs_plugin_get_name (old_plugin),
+			   gs_plugin_get_name (management_plugin));
+		return;
+	}
+
+	g_weak_ref_set (&priv->management_plugin_weak, management_plugin);
+}
+
+/**
+ * gs_app_get_rating:
+ * @app: a #GsApp
+ *
+ * Gets the percentage rating of the application, where 100 is 5 stars.
+ *
+ * Returns: a percentage, or -1 for unset
+ *
+ * Since: 3.22
+ **/
+gint
+gs_app_get_rating (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), -1);
+	return priv->rating;
+}
+
+/**
+ * gs_app_set_rating:
+ * @app: a #GsApp
+ * @rating: a percentage, or -1 for invalid
+ *
+ * Gets the percentage rating of the application.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_rating (GsApp *app, gint rating)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	if (rating == priv->rating)
+		return;
+	priv->rating = rating;
+	gs_app_queue_notify (app, obj_props[PROP_RATING]);
+}
+
+/**
+ * gs_app_get_review_ratings:
+ * @app: a #GsApp
+ *
+ * Gets the review ratings.
+ *
+ * Returns: (element-type guint32) (transfer none): a list
+ *
+ * Since: 3.22
+ **/
+GArray *
+gs_app_get_review_ratings (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->review_ratings;
+}
+
+/**
+ * gs_app_set_review_ratings:
+ * @app: a #GsApp
+ * @review_ratings: (element-type guint32): a list
+ *
+ * Sets the review ratings.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_review_ratings (GsApp *app, GArray *review_ratings)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	_g_set_array (&priv->review_ratings, review_ratings);
+}
+
+/**
+ * gs_app_get_reviews:
+ * @app: a #GsApp
+ *
+ * Gets all the user-submitted reviews for the application.
+ *
+ * Returns: (element-type AsReview) (transfer none): the list of reviews
+ *
+ * Since: 3.22
+ **/
+GPtrArray *
+gs_app_get_reviews (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->reviews;
+}
+
+/**
+ * gs_app_add_review:
+ * @app: a #GsApp
+ * @review: a #AsReview
+ *
+ * Adds a user-submitted review to the application.
+ *
+ * Since: 40
+ **/
+void
+gs_app_add_review (GsApp *app, AsReview *review)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (AS_IS_REVIEW (review));
+	locker = g_mutex_locker_new (&priv->mutex);
+	g_ptr_array_add (priv->reviews, g_object_ref (review));
+}
+
+/**
+ * gs_app_remove_review:
+ * @app: a #GsApp
+ * @review: a #AsReview
+ *
+ * Removes a user-submitted review to the application.
+ *
+ * Since: 40
+ **/
+void
+gs_app_remove_review (GsApp *app, AsReview *review)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	g_ptr_array_remove (priv->reviews, review);
+}
+
+/**
+ * gs_app_get_provided:
+ * @app: a #GsApp
+ *
+ * Gets all the provided item sets for the application.
+ *
+ * Returns: (element-type AsProvided) (transfer none): the list of provided items
+ *
+ * Since: 40
+ **/
+GPtrArray*
+gs_app_get_provided (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->provided;
+}
+
+/**
+ * gs_app_get_provided_for_kind:
+ * @cpt: a #AsComponent instance.
+ * @kind: kind of the provided item, e.g. %AS_PROVIDED_KIND_MIMETYPE
+ *
+ * Get an #AsProvided object for the given interface type, or %NULL if
+ * none was found.
+ *
+ * Returns: (nullable) (transfer none): the #AsProvided
+ *
+ * Since: 40
+ */
+AsProvided*
+gs_app_get_provided_for_kind (GsApp *app, AsProvidedKind kind)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+
+	for (guint i = 0; i < priv->provided->len; i++) {
+		AsProvided *prov = AS_PROVIDED (g_ptr_array_index (priv->provided, i));
+		if (as_provided_get_kind (prov) == kind)
+			return prov;
+	}
+	return NULL;
+}
+
+/**
+ * gs_app_add_provided:
+ * @app: a #GsApp
+ * @kind: the kind of the provided item, e.g. %AS_PROVIDED_KIND_MEDIATYPE
+ * @item: the item to add.
+ *
+ * Adds a provided items of the given kind to the application.
+ *
+ * Since: 40
+ **/
+void
+gs_app_add_provided_item (GsApp *app, AsProvidedKind kind, const gchar *item)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	AsProvided *prov;
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (item != NULL);
+	g_return_if_fail (kind != AS_PROVIDED_KIND_UNKNOWN && kind < AS_PROVIDED_KIND_LAST);
+
+	locker = g_mutex_locker_new (&priv->mutex);
+	prov = gs_app_get_provided_for_kind (app, kind);
+	if (prov == NULL) {
+		prov = as_provided_new ();
+		as_provided_set_kind (prov, kind);
+		g_ptr_array_add (priv->provided, prov);
+	}
+	as_provided_add_item (prov, item);
+}
+
+/**
+ * gs_app_get_size_download:
+ * @app: A #GsApp
+ * @size_bytes_out: (optional) (out caller-allocates): return location for
+ *   the download size, in bytes, or %NULL to ignore
+ *
+ * Get the values of #GsApp:size-download-type and #GsApp:size-download.
+ *
+ * If this returns %GS_SIZE_TYPE_VALID, @size_bytes_out (if non-%NULL) will be
+ * set to the download size. Otherwise, its value will be undefined.
+ *
+ * Returns: type of the download size
+ * Since: 43
+ **/
+GsSizeType
+gs_app_get_size_download (GsApp   *app,
+                          guint64 *size_bytes_out)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	g_return_val_if_fail (GS_IS_APP (app), GS_SIZE_TYPE_UNKNOWN);
+
+	if (size_bytes_out != NULL)
+		*size_bytes_out = (priv->size_download_type == GS_SIZE_TYPE_VALID) ? priv->size_download : 0;
+
+	return priv->size_download_type;
+}
+
+/**
+ * gs_app_set_size_download:
+ * @app: a #GsApp
+ * @size_type: type of the download size
+ * @size_bytes: size in bytes
+ *
+ * Sets the download size of the application, not including any
+ * required runtime.
+ *
+ * @size_bytes will be ignored unless @size_type is %GS_SIZE_TYPE_VALID.
+ *
+ * Since: 43
+ **/
+void
+gs_app_set_size_download (GsApp      *app,
+                          GsSizeType  size_type,
+                          guint64     size_bytes)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	g_return_if_fail (GS_IS_APP (app));
+
+	if (size_type != GS_SIZE_TYPE_VALID)
+		size_bytes = 0;
+
+	if (priv->size_download_type != size_type) {
+		priv->size_download_type = size_type;
+		gs_app_queue_notify (app, obj_props[PROP_SIZE_DOWNLOAD_TYPE]);
+	}
+
+	if (priv->size_download != size_bytes) {
+		priv->size_download = size_bytes;
+		gs_app_queue_notify (app, obj_props[PROP_SIZE_DOWNLOAD]);
+	}
+}
+
+/* Add two sizes, accounting for their validity, and checking for overflow. This
+ * is essentially `out_bytes = a_bytes + b_bytes` with additional checking.
+ *
+ * If either of @a_type or @b_type is %GS_SIZE_TYPE_UNKNOWN or
+ * %GS_SIZE_TYPE_UNKNOWABLE, that type will be propagated to @out_type.
+ *
+ * If the sum of @a_bytes and @b_bytes exceeds %G_MAXUINT64, the result in
+ * @out_bytes will silently be clamped to %G_MAXUINT64.
+ *
+ * The lifetime of @app must be at least as long as the lifetime of
+ * @covered_uids, which allows us to avoid some string copies.
+ */
+static gboolean
+add_sizes (GsApp      *app,
+           GHashTable *covered_uids,
+           GsSizeType  a_type,
+           guint64     a_bytes,
+           GsSizeType  b_type,
+           guint64     b_bytes,
+           GsSizeType *out_type,
+           guint64    *out_bytes)
+{
+	g_return_val_if_fail (out_type != NULL, FALSE);
+	g_return_val_if_fail (out_bytes != NULL, FALSE);
+
+	if (app != NULL && covered_uids != NULL) {
+		const gchar *id = gs_app_get_unique_id (app);
+		if (id != NULL &&
+		    !g_hash_table_add (covered_uids, (gpointer) id))
+			return TRUE;
+	}
+
+	if (a_type == GS_SIZE_TYPE_VALID && b_type == GS_SIZE_TYPE_VALID) {
+		*out_type = GS_SIZE_TYPE_VALID;
+		if (!g_uint64_checked_add (out_bytes, a_bytes, b_bytes))
+			*out_bytes = G_MAXUINT64;
+		return TRUE;
+	}
+
+	*out_type = (a_type == GS_SIZE_TYPE_UNKNOWABLE || b_type == GS_SIZE_TYPE_UNKNOWABLE) ? GS_SIZE_TYPE_UNKNOWABLE : GS_SIZE_TYPE_UNKNOWN;
+	*out_bytes = 0;
+
+	return FALSE;
+}
+
+static GsSizeType
+get_size_download_dependencies (GsApp *app,
+				guint64 *size_bytes_out,
+				GHashTable *covered_uids)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	GsSizeType size_type = GS_SIZE_TYPE_VALID;
+	guint64 size_bytes = 0;
+
+	g_return_val_if_fail (GS_IS_APP (app), GS_SIZE_TYPE_UNKNOWN);
+
+	/* add the runtime if this is not installed */
+	if (priv->runtime != NULL &&
+	    gs_app_get_state (priv->runtime) == GS_APP_STATE_AVAILABLE) {
+		GsSizeType runtime_size_download_type, runtime_size_download_dependencies_type;
+		guint64 runtime_size_download_bytes, runtime_size_download_dependencies_bytes;
+
+		runtime_size_download_type = gs_app_get_size_download (priv->runtime, &runtime_size_download_bytes);
+
+		if (add_sizes (priv->runtime, covered_uids,
+			       size_type, size_bytes,
+			       runtime_size_download_type, runtime_size_download_bytes,
+			       &size_type, &size_bytes)) {
+			runtime_size_download_dependencies_type = get_size_download_dependencies (priv->runtime,
+												  &runtime_size_download_dependencies_bytes,
+												  covered_uids);
+
+			add_sizes (NULL, NULL,
+				   size_type, size_bytes,
+				   runtime_size_download_dependencies_type, runtime_size_download_dependencies_bytes,
+				   &size_type, &size_bytes);
+		}
+	}
+
+	/* add related apps */
+	for (guint i = 0; i < gs_app_list_length (priv->related); i++) {
+		GsApp *app_related = gs_app_list_index (priv->related, i);
+		GsSizeType related_size_download_type, related_size_download_dependencies_type;
+		guint64 related_size_download_bytes, related_size_download_dependencies_bytes;
+
+		related_size_download_type = gs_app_get_size_download (app_related, &related_size_download_bytes);
+
+		if (!add_sizes (app_related, covered_uids,
+				size_type, size_bytes,
+				related_size_download_type, related_size_download_bytes,
+				&size_type, &size_bytes))
+			break;
+
+		related_size_download_dependencies_type = get_size_download_dependencies (app_related,
+											  &related_size_download_dependencies_bytes,
+											  covered_uids);
+
+		if (!add_sizes (NULL, NULL,
+				size_type, size_bytes,
+				related_size_download_dependencies_type, related_size_download_dependencies_bytes,
+				&size_type, &size_bytes))
+			break;
+	}
+
+	if (size_bytes_out != NULL)
+		*size_bytes_out = (size_type == GS_SIZE_TYPE_VALID) ? size_bytes : 0;
+
+	return size_type;
+}
+
+/**
+ * gs_app_get_size_download_dependencies:
+ * @app: A #GsApp
+ * @size_bytes_out: (optional) (out caller-allocates): return location for
+ *   the download size of dependencies, in bytes, or %NULL to ignore
+ *
+ * Get the value of #GsApp:size-download-dependencies-type and
+ * #GsApp:size-download-dependencies.
+ *
+ * If this returns %GS_SIZE_TYPE_VALID, @size_bytes_out (if non-%NULL) will be
+ * set to the download size of dependencies. Otherwise, its value will be
+ * undefined.
+ *
+ * Returns: type of the download size of dependencies
+ * Since: 43
+ **/
+GsSizeType
+gs_app_get_size_download_dependencies (GsApp   *app,
+                                       guint64 *size_bytes_out)
+{
+	g_autoptr(GHashTable) covered_uids = NULL;
+
+	g_return_val_if_fail (GS_IS_APP (app), GS_SIZE_TYPE_UNKNOWN);
+
+	covered_uids = g_hash_table_new_full ((GHashFunc) as_utils_data_id_hash, (GEqualFunc) as_utils_data_id_equal, NULL, NULL);
+
+	return get_size_download_dependencies (app, size_bytes_out, covered_uids);
+}
+
+/**
+ * gs_app_get_size_installed:
+ * @app: a #GsApp
+ * @size_bytes_out: (optional) (out caller-allocates): return location for
+ *   the installed size, in bytes, or %NULL to ignore
+ *
+ * Get the values of #GsApp:size-installed-type and #GsApp:size-installed.
+ *
+ * If this returns %GS_SIZE_TYPE_VALID, @size_bytes_out (if non-%NULL) will be
+ * set to the installed size. Otherwise, its value will be undefined.
+ *
+ * Returns: type of the installed size
+ * Since: 43
+ **/
+GsSizeType
+gs_app_get_size_installed (GsApp   *app,
+                           guint64 *size_bytes_out)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	g_return_val_if_fail (GS_IS_APP (app), GS_SIZE_TYPE_UNKNOWN);
+
+	if (size_bytes_out != NULL)
+		*size_bytes_out = (priv->size_installed_type == GS_SIZE_TYPE_VALID) ? priv->size_installed : 0;
+
+	return priv->size_installed_type;
+}
+
+/**
+ * gs_app_set_size_installed:
+ * @app: a #GsApp
+ * @size_type: type of the installed size
+ * @size_bytes: size in bytes
+ *
+ * Sets the installed size of the application.
+ *
+ * @size_bytes will be ignored unless @size_type is %GS_SIZE_TYPE_VALID.
+ *
+ * Since: 43
+ **/
+void
+gs_app_set_size_installed (GsApp      *app,
+                           GsSizeType  size_type,
+                           guint64     size_bytes)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	g_return_if_fail (GS_IS_APP (app));
+
+	if (size_type != GS_SIZE_TYPE_VALID)
+		size_bytes = 0;
+
+	if (priv->size_installed_type != size_type) {
+		priv->size_installed_type = size_type;
+		gs_app_queue_notify (app, obj_props[PROP_SIZE_INSTALLED_TYPE]);
+	}
+
+	if (priv->size_installed != size_bytes) {
+		priv->size_installed = size_bytes;
+		gs_app_queue_notify (app, obj_props[PROP_SIZE_INSTALLED]);
+	}
+}
+
+static GsSizeType
+get_size_installed_dependencies (GsApp *app,
+				 guint64 *size_bytes_out,
+				 GHashTable *covered_uids)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	GsSizeType size_type = GS_SIZE_TYPE_VALID;
+	guint64 size_bytes = 0;
+
+	g_return_val_if_fail (GS_IS_APP (app), GS_SIZE_TYPE_UNKNOWN);
+
+	/* add related apps */
+	for (guint i = 0; i < gs_app_list_length (priv->related); i++) {
+		GsApp *app_related = gs_app_list_index (priv->related, i);
+		GsSizeType related_size_installed_type, related_size_installed_dependencies_type;
+		guint64 related_size_installed_bytes, related_size_installed_dependencies_bytes;
+
+		related_size_installed_type = gs_app_get_size_installed (app_related, &related_size_installed_bytes);
+
+		if (!add_sizes (app_related, covered_uids,
+				size_type, size_bytes,
+				related_size_installed_type, related_size_installed_bytes,
+				&size_type, &size_bytes))
+			break;
+
+		related_size_installed_dependencies_type = get_size_installed_dependencies (app_related,
+											    &related_size_installed_dependencies_bytes,
+											    covered_uids);
+
+		if (!add_sizes (NULL, NULL,
+				size_type, size_bytes,
+				related_size_installed_dependencies_type, related_size_installed_dependencies_bytes,
+				&size_type, &size_bytes))
+			break;
+	}
+
+	if (size_bytes_out != NULL)
+		*size_bytes_out = (size_type == GS_SIZE_TYPE_VALID) ? size_bytes : 0;
+
+	return size_type;
+}
+
+/**
+ * gs_app_get_size_installed_dependencies:
+ * @app: a #GsApp
+ * @size_bytes_out: (optional) (out caller-allocates): return location for
+ *   the installed size of dependencies, in bytes, or %NULL to ignore
+ *
+ * Get the values of #GsApp:size-installed-dependencies-type and
+ * #GsApp:size-installed-dependencies.
+ *
+ * If this returns %GS_SIZE_TYPE_VALID, @size_bytes_out (if non-%NULL) will be
+ * set to the installed size of dependencies. Otherwise, its value will be
+ * undefined.
+ *
+ * Returns: type of the installed size of dependencies
+ * Since: 43
+ **/
+GsSizeType
+gs_app_get_size_installed_dependencies (GsApp   *app,
+                                        guint64 *size_bytes_out)
+{
+	g_autoptr(GHashTable) covered_uids = NULL;
+
+	g_return_val_if_fail (GS_IS_APP (app), GS_SIZE_TYPE_UNKNOWN);
+
+	covered_uids = g_hash_table_new_full ((GHashFunc) as_utils_data_id_hash, (GEqualFunc) as_utils_data_id_equal, NULL, NULL);
+
+	return get_size_installed_dependencies (app, size_bytes_out, covered_uids);
+}
+
+/**
+ * gs_app_get_size_user_data:
+ * @app: A #GsApp
+ * @size_bytes_out: (optional) (out caller-allocates): return location for
+ *   the user data size, in bytes, or %NULL to ignore
+ *
+ * Get the values of #GsApp:size-user-data-type and #GsApp:size-user-data.
+ *
+ * If this returns %GS_SIZE_TYPE_VALID, @size_bytes_out (if non-%NULL) will be
+ * set to the user data size. Otherwise, its value will be undefined.
+ *
+ * Returns: type of the user data size
+ * Since: 43
+ **/
+GsSizeType
+gs_app_get_size_user_data (GsApp   *app,
+                           guint64 *size_bytes_out)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	g_return_val_if_fail (GS_IS_APP (app), GS_SIZE_TYPE_UNKNOWN);
+
+	if (size_bytes_out != NULL)
+		*size_bytes_out = (priv->size_user_data_type == GS_SIZE_TYPE_VALID) ? priv->size_user_data : 0;
+
+	return priv->size_user_data_type;
+}
+
+/**
+ * gs_app_set_size_user_data:
+ * @app: a #GsApp
+ * @size_type: type of the user data size
+ * @size_bytes: size in bytes
+ *
+ * Sets the user data size of the @app.
+ *
+ * @size_bytes will be ignored unless @size_type is %GS_SIZE_TYPE_VALID.
+ *
+ * Since: 43
+ **/
+void
+gs_app_set_size_user_data (GsApp      *app,
+                           GsSizeType  size_type,
+                           guint64     size_bytes)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	g_return_if_fail (GS_IS_APP (app));
+
+	if (size_type != GS_SIZE_TYPE_VALID)
+		size_bytes = 0;
+
+	if (priv->size_user_data_type != size_type) {
+		priv->size_user_data_type = size_type;
+		gs_app_queue_notify (app, obj_props[PROP_SIZE_USER_DATA_TYPE]);
+	}
+
+	if (priv->size_user_data != size_bytes) {
+		priv->size_user_data = size_bytes;
+		gs_app_queue_notify (app, obj_props[PROP_SIZE_USER_DATA]);
+	}
+}
+
+/**
+ * gs_app_get_size_cache_data:
+ * @app: A #GsApp
+ * @size_bytes_out: (optional) (out caller-allocates): return location for
+ *   the cache data size, in bytes, or %NULL to ignore
+ *
+ * Get the values of #GsApp:size-cache-data-type and #GsApp:size-cache-data.
+ *
+ * If this returns %GS_SIZE_TYPE_VALID, @size_bytes_out (if non-%NULL) will be
+ * set to the cache data size. Otherwise, its value will be undefined.
+ *
+ * Returns: type of the cache data size
+ * Since: 43
+ **/
+GsSizeType
+gs_app_get_size_cache_data (GsApp   *app,
+                            guint64 *size_bytes_out)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	g_return_val_if_fail (GS_IS_APP (app), GS_SIZE_TYPE_UNKNOWN);
+
+	if (size_bytes_out != NULL)
+		*size_bytes_out = (priv->size_cache_data_type == GS_SIZE_TYPE_VALID) ? priv->size_cache_data : 0;
+
+	return priv->size_cache_data_type;
+}
+
+/**
+ * gs_app_set_size_cache_data:
+ * @app: a #GsApp
+ * @size_type: type of the cache data size
+ * @size_bytes: size in bytes
+ *
+ * Sets the cache data size of the @app.
+ *
+ * @size_bytes will be ignored unless @size_type is %GS_SIZE_TYPE_VALID.
+ *
+ * Since: 43
+ **/
+void
+gs_app_set_size_cache_data (GsApp      *app,
+                            GsSizeType  size_type,
+                            guint64     size_bytes)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	g_return_if_fail (GS_IS_APP (app));
+
+	if (size_type != GS_SIZE_TYPE_VALID)
+		size_bytes = 0;
+
+	if (priv->size_cache_data_type != size_type) {
+		priv->size_cache_data_type = size_type;
+		gs_app_queue_notify (app, obj_props[PROP_SIZE_CACHE_DATA_TYPE]);
+	}
+
+	if (priv->size_cache_data != size_bytes) {
+		priv->size_cache_data = size_bytes;
+		gs_app_queue_notify (app, obj_props[PROP_SIZE_CACHE_DATA]);
+	}
+}
+
+/**
+ * gs_app_get_metadata_item:
+ * @app: a #GsApp
+ * @key: a string, e.g. "fwupd::device-id"
+ *
+ * Gets some metadata for the application.
+ * Is is expected that plugins namespace any plugin-specific metadata,
+ * for example `fwupd::device-id`.
+ *
+ * Returns: a string, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_app_get_metadata_item (GsApp *app, const gchar *key)
+{
+	GVariant *tmp;
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	g_return_val_if_fail (key != NULL, NULL);
+	tmp = gs_app_get_metadata_variant (app, key);
+	if (tmp == NULL)
+		return NULL;
+	return g_variant_get_string (tmp, NULL);
+}
+
+/**
+ * gs_app_set_metadata:
+ * @app: a #GsApp
+ * @key: a string, e.g. "fwupd::DeviceID"
+ * @value: a string, e.g. "fubar"
+ *
+ * Sets some metadata for the application.
+ * Is is expected that plugins namespace any plugin-specific metadata.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_metadata (GsApp *app, const gchar *key, const gchar *value)
+{
+	g_autoptr(GVariant) tmp = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (key != NULL);
+	if (value != NULL)
+		tmp = g_variant_new_string (value);
+	gs_app_set_metadata_variant (app, key, tmp);
+}
+
+/**
+ * gs_app_get_metadata_variant:
+ * @app: a #GsApp
+ * @key: a string, e.g. "fwupd::device-id"
+ *
+ * Gets some metadata for the application.
+ * Is is expected that plugins namespace any plugin-specific metadata.
+ *
+ * Returns: (transfer none) (nullable): a variant, or %NULL for unset
+ *
+ * Since: 3.26
+ **/
+GVariant *
+gs_app_get_metadata_variant (GsApp *app, const gchar *key)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	g_return_val_if_fail (key != NULL, NULL);
+	return g_hash_table_lookup (priv->metadata, key);
+}
+
+/**
+ * gs_app_set_metadata_variant:
+ * @app: a #GsApp
+ * @key: a string, e.g. "fwupd::DeviceID"
+ * @value: a #GVariant
+ *
+ * Sets some metadata for the application.
+ * Is is expected that plugins namespace any plugin-specific metadata,
+ * for example `fwupd::device-id`.
+ *
+ * Since: 3.26
+ **/
+void
+gs_app_set_metadata_variant (GsApp *app, const gchar *key, GVariant *value)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	GVariant *found;
+
+	g_return_if_fail (GS_IS_APP (app));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	/* if no value, then remove the key */
+	if (value == NULL) {
+		g_hash_table_remove (priv->metadata, key);
+		return;
+	}
+
+	/* check we're not overwriting */
+	found = g_hash_table_lookup (priv->metadata, key);
+	if (found != NULL) {
+		if (g_variant_equal (found, value))
+			return;
+		if (g_variant_type_equal (g_variant_get_type (value), G_VARIANT_TYPE_STRING) &&
+		    g_variant_type_equal (g_variant_get_type (found), G_VARIANT_TYPE_STRING)) {
+			g_debug ("tried overwriting %s key %s from %s to %s",
+				 priv->id, key,
+				 g_variant_get_string (found, NULL),
+				 g_variant_get_string (value, NULL));
+		} else {
+			g_debug ("tried overwriting %s key %s (%s->%s)",
+				 priv->id, key,
+				 g_variant_get_type_string (found),
+				 g_variant_get_type_string (value));
+		}
+		return;
+	}
+	g_hash_table_insert (priv->metadata, g_strdup (key), g_variant_ref (value));
+}
+
+/**
+ * gs_app_dup_addons:
+ * @app: a #GsApp
+ *
+ * Gets the list of addons for the application.
+ *
+ * Returns: (transfer full) (nullable): a list of addons, or %NULL if there are none
+ *
+ * Since: 43
+ */
+GsAppList *
+gs_app_dup_addons (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	locker = g_mutex_locker_new (&priv->mutex);
+	return (priv->addons != NULL) ? g_object_ref (priv->addons) : NULL;
+}
+
+/**
+ * gs_app_add_addons:
+ * @app: a #GsApp
+ * @addons: (transfer none) (not nullable): a list of #GsApps
+ *
+ * Adds zero or more addons to the list of application addons.
+ *
+ * Since: 43
+ **/
+void
+gs_app_add_addons (GsApp     *app,
+                   GsAppList *addons)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_autoptr(GsAppList) new_addons = NULL;
+
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (GS_IS_APP_LIST (addons));
+
+	if (gs_app_list_length (addons) == 0)
+		return;
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	if (priv->addons != NULL)
+		new_addons = gs_app_list_copy (priv->addons);
+	else
+		new_addons = gs_app_list_new ();
+	gs_app_list_add_list (new_addons, addons);
+
+	g_set_object (&priv->addons, new_addons);
+}
+
+/**
+ * gs_app_remove_addon:
+ * @app: a #GsApp
+ * @addon: a #GsApp
+ *
+ * Removes an addon from the list of application addons.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_remove_addon (GsApp *app, GsApp *addon)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (GS_IS_APP (addon));
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	if (priv->addons != NULL)
+		gs_app_list_remove (priv->addons, addon);
+}
+
+/**
+ * gs_app_get_related:
+ * @app: a #GsApp
+ *
+ * Gets any related applications.
+ *
+ * Returns: (transfer none): a list of applications
+ *
+ * Since: 3.22
+ **/
+GsAppList *
+gs_app_get_related (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->related;
+}
+
+/**
+ * gs_app_add_related:
+ * @app: a #GsApp
+ * @app2: a #GsApp
+ *
+ * Adds a related application.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_add_related (GsApp *app, GsApp *app2)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	GsAppPrivate *priv2 = gs_app_get_instance_private (app2);
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (GS_IS_APP (app2));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	/* if the app is updatable-live and any related app is not then
+	 * degrade to the offline state */
+	if (priv->state == GS_APP_STATE_UPDATABLE_LIVE &&
+	    priv2->state == GS_APP_STATE_UPDATABLE)
+		priv->state = priv2->state;
+
+	gs_app_list_add (priv->related, app2);
+
+	/* The related apps add to the main app’s sizes. */
+	gs_app_queue_notify (app, obj_props[PROP_SIZE_DOWNLOAD_DEPENDENCIES_TYPE]);
+	gs_app_queue_notify (app, obj_props[PROP_SIZE_DOWNLOAD_DEPENDENCIES]);
+	gs_app_queue_notify (app, obj_props[PROP_SIZE_INSTALLED_DEPENDENCIES_TYPE]);
+	gs_app_queue_notify (app, obj_props[PROP_SIZE_INSTALLED_DEPENDENCIES]);
+}
+
+/**
+ * gs_app_get_history:
+ * @app: a #GsApp
+ *
+ * Gets the history of this application.
+ *
+ * Returns: (transfer none): a list
+ *
+ * Since: 3.22
+ **/
+GsAppList *
+gs_app_get_history (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->history;
+}
+
+/**
+ * gs_app_add_history:
+ * @app: a #GsApp
+ * @app2: a #GsApp
+ *
+ * Adds a history item for this package.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_add_history (GsApp *app, GsApp *app2)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (GS_IS_APP (app2));
+	locker = g_mutex_locker_new (&priv->mutex);
+	gs_app_list_add (priv->history, app2);
+}
+
+/**
+ * gs_app_get_install_date:
+ * @app: a #GsApp
+ *
+ * Gets the date that an application was installed.
+ *
+ * Returns: A UNIX epoch, or 0 for unset
+ *
+ * Since: 3.22
+ **/
+guint64
+gs_app_get_install_date (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), 0);
+	return priv->install_date;
+}
+
+/**
+ * gs_app_set_install_date:
+ * @app: a #GsApp
+ * @install_date: an epoch, or %GS_APP_INSTALL_DATE_UNKNOWN
+ *
+ * Sets the date that an application was installed.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_install_date (GsApp *app, guint64 install_date)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_if_fail (GS_IS_APP (app));
+	if (install_date == priv->install_date)
+		return;
+	priv->install_date = install_date;
+}
+
+/**
+ * gs_app_get_release_date:
+ * @app: a #GsApp
+ *
+ * Gets the date that an application was released.
+ *
+ * Returns: A UNIX epoch, or 0 for unset
+ *
+ * Since: 3.40
+ **/
+guint64
+gs_app_get_release_date (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), 0);
+	return priv->release_date;
+}
+
+/**
+ * gs_app_set_release_date:
+ * @app: a #GsApp
+ * @release_date: an epoch, or 0
+ *
+ * Sets the date that an application was released.
+ *
+ * Since: 3.40
+ **/
+void
+gs_app_set_release_date (GsApp *app, guint64 release_date)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_if_fail (GS_IS_APP (app));
+	if (release_date == priv->release_date)
+		return;
+	priv->release_date = release_date;
+
+	gs_app_queue_notify (app, obj_props[PROP_RELEASE_DATE]);
+}
+
+/**
+ * gs_app_is_installed:
+ * @app: a #GsApp
+ *
+ * Gets whether the app is installed or not.
+ *
+ * Returns: %TRUE if the app is installed, %FALSE otherwise.
+ *
+ * Since: 3.22
+ **/
+gboolean
+gs_app_is_installed (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+	return (priv->state == GS_APP_STATE_INSTALLED) ||
+	       (priv->state == GS_APP_STATE_UPDATABLE) ||
+	       (priv->state == GS_APP_STATE_UPDATABLE_LIVE) ||
+	       (priv->state == GS_APP_STATE_REMOVING);
+}
+
+/**
+ * gs_app_is_updatable:
+ * @app: a #GsApp
+ *
+ * Gets whether the app is updatable or not.
+ *
+ * Returns: %TRUE if the app is updatable, %FALSE otherwise.
+ *
+ * Since: 3.22
+ **/
+gboolean
+gs_app_is_updatable (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+	if (priv->kind == AS_COMPONENT_KIND_OPERATING_SYSTEM)
+		return TRUE;
+	return (priv->state == GS_APP_STATE_UPDATABLE) ||
+	       (priv->state == GS_APP_STATE_UPDATABLE_LIVE);
+}
+
+/**
+ * gs_app_get_categories:
+ * @app: a #GsApp
+ *
+ * Gets the list of categories for an application.
+ *
+ * Returns: (element-type utf8) (transfer none): a list
+ *
+ * Since: 3.22
+ **/
+GPtrArray *
+gs_app_get_categories (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	return priv->categories;
+}
+
+/**
+ * gs_app_has_category:
+ * @app: a #GsApp
+ * @category: a category ID, e.g. "AudioVideo"
+ *
+ * Checks if the application is in a specific category.
+ *
+ * Returns: %TRUE for success
+ *
+ * Since: 3.22
+ **/
+gboolean
+gs_app_has_category (GsApp *app, const gchar *category)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	const gchar *tmp;
+	guint i;
+
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+
+	/* find the category */
+	for (i = 0; i < priv->categories->len; i++) {
+		tmp = g_ptr_array_index (priv->categories, i);
+		if (g_strcmp0 (tmp, category) == 0)
+			return TRUE;
+	}
+	return FALSE;
+}
+
+/**
+ * gs_app_set_categories:
+ * @app: a #GsApp
+ * @categories: a set of categories
+ *
+ * Set the list of categories for an application.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_categories (GsApp *app, GPtrArray *categories)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (categories != NULL);
+	locker = g_mutex_locker_new (&priv->mutex);
+	_g_set_ptr_array (&priv->categories, categories);
+}
+
+/**
+ * gs_app_add_category:
+ * @app: a #GsApp
+ * @category: a category ID, e.g. "AudioVideo"
+ *
+ * Adds a category ID to an application.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_add_category (GsApp *app, const gchar *category)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (category != NULL);
+	locker = g_mutex_locker_new (&priv->mutex);
+	if (gs_app_has_category (app, category))
+		return;
+	g_ptr_array_add (priv->categories, g_strdup (category));
+}
+
+/**
+ * gs_app_remove_category:
+ * @app: a #GsApp
+ * @category: a category ID, e.g. "AudioVideo"
+ *
+ * Removes an category ID from an application, it exists.
+ *
+ * Returns: %TRUE for success
+ *
+ * Since: 3.24
+ **/
+gboolean
+gs_app_remove_category (GsApp *app, const gchar *category)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	const gchar *tmp;
+	guint i;
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	for (i = 0; i < priv->categories->len; i++) {
+		tmp = g_ptr_array_index (priv->categories, i);
+		if (g_strcmp0 (tmp, category) != 0)
+			continue;
+		g_ptr_array_remove_index_fast (priv->categories, i);
+		return TRUE;
+	}
+	return FALSE;
+}
+
+/**
+ * gs_app_set_is_update_downloaded:
+ * @app: a #GsApp
+ * @is_update_downloaded: Whether a new update is already downloaded locally
+ *
+ * Sets if the new update is already downloaded for the app.
+ *
+ * Since: 3.36
+ **/
+void
+gs_app_set_is_update_downloaded (GsApp *app, gboolean is_update_downloaded)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_if_fail (GS_IS_APP (app));
+	priv->is_update_downloaded = is_update_downloaded;
+}
+
+/**
+ * gs_app_get_is_update_downloaded:
+ * @app: a #GsApp
+ *
+ * Gets if the new update is already downloaded for the app and
+ * is locally available.
+ *
+ * Returns: (element-type gboolean): Whether a new update for the #GsApp is already downloaded.
+ *
+ * Since: 3.36
+ **/
+gboolean
+gs_app_get_is_update_downloaded (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+	return priv->is_update_downloaded;
+}
+
+static void
+calculate_key_colors (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GIcon) icon_small = NULL;
+	g_autoptr(GdkPixbuf) pb_small = NULL;
+	const gchar *overrides_str;
+
+	/* Lazily create the array */
+	if (priv->key_colors == NULL)
+		priv->key_colors = g_array_new (FALSE, FALSE, sizeof (GdkRGBA));
+	priv->user_key_colors = FALSE;
+
+	/* Look for an override first. Parse and use it if possible. This is
+	 * typically specified in the appdata for an app as:
+	 * |[
+	 * <component>
+	 *   <custom>
+	 *     <value key="GnomeSoftware::key-colors">[(124, 53, 77), (99, 16, 0)]</value>
+	 *   </custom>
+	 * </component>
+	 * ]|
+	 */
+	overrides_str = gs_app_get_metadata_item (app, "GnomeSoftware::key-colors");
+	if (overrides_str != NULL) {
+		g_autoptr(GVariant) overrides = NULL;
+		g_autoptr(GError) local_error = NULL;
+
+		overrides = g_variant_parse (G_VARIANT_TYPE ("a(yyy)"),
+					     overrides_str,
+					     NULL,
+					     NULL,
+					     &local_error);
+
+		if (overrides != NULL && g_variant_n_children (overrides) > 0) {
+			GVariantIter iter;
+			guint8 red, green, blue;
+
+			g_variant_iter_init (&iter, overrides);
+			while (g_variant_iter_loop (&iter, "(yyy)", &red, &green, &blue)) {
+				GdkRGBA rgba;
+				rgba.red = (gdouble) red / 255.0;
+				rgba.green = (gdouble) green / 255.0;
+				rgba.blue = (gdouble) blue / 255.0;
+				rgba.alpha = 1.0;
+				g_array_append_val (priv->key_colors, rgba);
+			}
+
+			priv->user_key_colors = TRUE;
+
+			return;
+		} else {
+			g_warning ("Invalid value for GnomeSoftware::key-colors for %s: %s",
+				   gs_app_get_id (app), local_error->message);
+			/* fall through */
+		}
+	}
+
+	/* Try and load the pixbuf. */
+	icon_small = gs_app_get_icon_for_size (app, 32, 1, NULL);
+
+	if (icon_small == NULL) {
+		g_debug ("no pixbuf, so no key colors");
+		return;
+	} else if (G_IS_LOADABLE_ICON (icon_small)) {
+		g_autoptr(GInputStream) icon_stream = g_loadable_icon_load (G_LOADABLE_ICON (icon_small), 32, NULL, NULL, NULL);
+		if (icon_stream)
+			pb_small = gdk_pixbuf_new_from_stream_at_scale (icon_stream, 32, 32, TRUE, NULL, NULL);
+	} else if (G_IS_THEMED_ICON (icon_small)) {
+		g_autoptr(GtkIconPaintable) icon_paintable = NULL;
+		g_autoptr(GtkIconTheme) theme = NULL;
+		GdkDisplay *display;
+
+		display = gdk_display_get_default ();
+		if (display != NULL) {
+			theme = g_object_ref (gtk_icon_theme_get_for_display (display));
+		} else {
+			const gchar *test_search_path;
+
+			/* This fallback path is needed for the unit tests,
+			 * which run without a screen, and in an environment
+			 * where the XDG dir variables don’t point to the system
+			 * datadir which contains the system icon theme. */
+			theme = gtk_icon_theme_new ();
+
+			test_search_path = g_getenv ("GS_SELF_TEST_ICON_THEME_PATH");
+			if (test_search_path != NULL) {
+				g_auto(GStrv) dirs = g_strsplit (test_search_path, ":", -1);
+				gtk_icon_theme_set_search_path (theme, (const char * const *)dirs);
+
+			}
+		}
+
+		icon_paintable = gtk_icon_theme_lookup_by_gicon (theme, icon_small,
+								 32, 1,
+								 gtk_get_locale_direction (),
+								 0);
+		if (icon_paintable != NULL) {
+			g_autoptr(GFile) file = NULL;
+			g_autofree gchar *path = NULL;
+
+			file = gtk_icon_paintable_get_file (icon_paintable);
+			if (file != NULL)
+				path = g_file_get_path (file);
+
+			if (path != NULL) {
+				pb_small = gdk_pixbuf_new_from_file_at_size (path, 32, 32, NULL);
+			} else {
+				g_autoptr(GskRenderNode) render_node = NULL;
+				g_autoptr(GtkSnapshot) snapshot = NULL;
+				cairo_surface_t *surface;
+				cairo_t *cr;
+
+				surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32, 32, 32);
+				cr = cairo_create (surface);
+
+				/* TODO: this can be done entirely on the GPU using shaders */
+				snapshot = gtk_snapshot_new ();
+				gdk_paintable_snapshot (GDK_PAINTABLE (icon_paintable),
+							GDK_SNAPSHOT (snapshot),
+							32.0,
+							32.0);
+
+				render_node = gtk_snapshot_free_to_node (g_steal_pointer (&snapshot));
+				gsk_render_node_draw (render_node, cr);
+
+				pb_small = gdk_pixbuf_get_from_surface (surface, 0, 0, 32, 32);
+
+				cairo_surface_destroy (surface);
+				cairo_destroy (cr);
+			}
+		}
+
+	} else {
+		g_debug ("unsupported pixbuf, so no key colors");
+		return;
+	}
+
+	if (pb_small == NULL) {
+		g_debug ("pixbuf couldn’t be loaded, so no key colors");
+		return;
+	}
+
+	/* get a list of key colors */
+	g_clear_pointer (&priv->key_colors, g_array_unref);
+	priv->key_colors = gs_calculate_key_colors (pb_small);
+}
+
+/**
+ * gs_app_get_key_colors:
+ * @app: a #GsApp
+ *
+ * Gets the key colors used in the application icon.
+ *
+ * Returns: (element-type GdkRGBA) (transfer none): a list
+ *
+ * Since: 40
+ **/
+GArray *
+gs_app_get_key_colors (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+
+	if (priv->key_colors == NULL)
+		calculate_key_colors (app);
+
+	return priv->key_colors;
+}
+
+/**
+ * gs_app_set_key_colors:
+ * @app: a #GsApp
+ * @key_colors: (element-type GdkRGBA): a set of key colors
+ *
+ * Sets the key colors used in the application icon.
+ *
+ * Since: 40
+ **/
+void
+gs_app_set_key_colors (GsApp *app, GArray *key_colors)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (key_colors != NULL);
+	locker = g_mutex_locker_new (&priv->mutex);
+	priv->user_key_colors = FALSE;
+	if (_g_set_array (&priv->key_colors, key_colors))
+		gs_app_queue_notify (app, obj_props[PROP_KEY_COLORS]);
+}
+
+/**
+ * gs_app_add_key_color:
+ * @app: a #GsApp
+ * @key_color: a #GdkRGBA
+ *
+ * Adds a key color used in the application icon.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_add_key_color (GsApp *app, GdkRGBA *key_color)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (key_color != NULL);
+
+	/* Lazily create the array */
+	if (priv->key_colors == NULL)
+		priv->key_colors = g_array_new (FALSE, FALSE, sizeof (GdkRGBA));
+
+	priv->user_key_colors = FALSE;
+	g_array_append_val (priv->key_colors, *key_color);
+	gs_app_queue_notify (app, obj_props[PROP_KEY_COLORS]);
+}
+
+/**
+ * gs_app_get_user_key_colors:
+ * @app: a #GsApp
+ *
+ * Returns whether the key colors provided by gs_app_get_key_colors()
+ * are set by the user (using `GnomeSoftware::key-colors`). %FALSE
+ * means the colors have been calculated from the @app icon.
+ *
+ * Returns: whether the key colors have been provided by the user.
+ *
+ * Since: 42
+ **/
+gboolean
+gs_app_get_user_key_colors (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+	return priv->user_key_colors;
+}
+
+/**
+ * gs_app_add_kudo:
+ * @app: a #GsApp
+ * @kudo: a #GsAppKudo, e.g. %GS_APP_KUDO_MY_LANGUAGE
+ *
+ * Adds a kudo to the application.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_add_kudo (GsApp *app, GsAppKudo kudo)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_if_fail (GS_IS_APP (app));
+	if (kudo & GS_APP_KUDO_SANDBOXED_SECURE)
+		kudo |= GS_APP_KUDO_SANDBOXED;
+	priv->kudos |= kudo;
+}
+
+/**
+ * gs_app_remove_kudo:
+ * @app: a #GsApp
+ * @kudo: a #GsAppKudo, e.g. %GS_APP_KUDO_MY_LANGUAGE
+ *
+ * Removes a kudo from the application.
+ *
+ * Since: 3.30
+ **/
+void
+gs_app_remove_kudo (GsApp *app, GsAppKudo kudo)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_if_fail (GS_IS_APP (app));
+	priv->kudos &= ~kudo;
+}
+
+/**
+ * gs_app_has_kudo:
+ * @app: a #GsApp
+ * @kudo: a #GsAppKudo, e.g. %GS_APP_KUDO_MY_LANGUAGE
+ *
+ * Finds out if a kudo has been awarded by the application.
+ *
+ * Returns: %TRUE if the app has the specified kudo
+ *
+ * Since: 3.22
+ **/
+gboolean
+gs_app_has_kudo (GsApp *app, GsAppKudo kudo)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+	return (priv->kudos & kudo) > 0;
+}
+
+/**
+ * gs_app_get_kudos:
+ * @app: a #GsApp
+ *
+ * Gets all the kudos the application has been awarded.
+ *
+ * Returns: the kudos, as a bitfield
+ *
+ * Since: 3.22
+ **/
+guint64
+gs_app_get_kudos (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), 0);
+	return priv->kudos;
+}
+
+/**
+ * gs_app_get_kudos_percentage:
+ * @app: a #GsApp
+ *
+ * Gets the kudos, as a percentage value.
+ *
+ * Returns: a percentage, with 0 for no kudos and a maximum of 100.
+ *
+ * Since: 3.22
+ **/
+guint
+gs_app_get_kudos_percentage (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	guint percentage = 0;
+
+	g_return_val_if_fail (GS_IS_APP (app), 0);
+
+	if ((priv->kudos & GS_APP_KUDO_MY_LANGUAGE) > 0)
+		percentage += 20;
+	if ((priv->kudos & GS_APP_KUDO_RECENT_RELEASE) > 0)
+		percentage += 20;
+	if ((priv->kudos & GS_APP_KUDO_FEATURED_RECOMMENDED) > 0)
+		percentage += 20;
+	if ((priv->kudos & GS_APP_KUDO_MODERN_TOOLKIT) > 0)
+		percentage += 20;
+	if ((priv->kudos & GS_APP_KUDO_SEARCH_PROVIDER) > 0)
+		percentage += 10;
+	if ((priv->kudos & GS_APP_KUDO_INSTALLS_USER_DOCS) > 0)
+		percentage += 10;
+	if ((priv->kudos & GS_APP_KUDO_USES_NOTIFICATIONS) > 0)
+		percentage += 20;
+	if ((priv->kudos & GS_APP_KUDO_HAS_KEYWORDS) > 0)
+		percentage += 5;
+	if ((priv->kudos & GS_APP_KUDO_HAS_SCREENSHOTS) > 0)
+		percentage += 20;
+	if ((priv->kudos & GS_APP_KUDO_HIGH_CONTRAST) > 0)
+		percentage += 20;
+	if ((priv->kudos & GS_APP_KUDO_HI_DPI_ICON) > 0)
+		percentage += 20;
+	if ((priv->kudos & GS_APP_KUDO_SANDBOXED) > 0)
+		percentage += 20;
+	if ((priv->kudos & GS_APP_KUDO_SANDBOXED_SECURE) > 0)
+		percentage += 20;
+
+	return MIN (percentage, 100);
+}
+
+/**
+ * gs_app_get_to_be_installed:
+ * @app: a #GsApp
+ *
+ * Gets if the application is queued for installation.
+ *
+ * This is only set for addons when the user has selected some addons to be
+ * installed before installing the main application.
+ * Plugins should check all the addons for this property when installing
+ * main applications so that the chosen set of addons is also installed at the
+ * same time. This is never set when applications do not have addons.
+ *
+ * Returns: %TRUE for success
+ *
+ * Since: 3.22
+ **/
+gboolean
+gs_app_get_to_be_installed (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+
+	return priv->to_be_installed;
+}
+
+/**
+ * gs_app_set_to_be_installed:
+ * @app: a #GsApp
+ * @to_be_installed: if the app is due to be installed
+ *
+ * Sets if the application is queued for installation.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_to_be_installed (GsApp *app, gboolean to_be_installed)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_if_fail (GS_IS_APP (app));
+
+	priv->to_be_installed = to_be_installed;
+}
+
+/**
+ * gs_app_has_quirk:
+ * @app: a #GsApp
+ * @quirk: a #GsAppQuirk, e.g. %GS_APP_QUIRK_COMPULSORY
+ *
+ * Finds out if an application has a specific quirk.
+ *
+ * Returns: %TRUE for success
+ *
+ * Since: 3.22
+ **/
+gboolean
+gs_app_has_quirk (GsApp *app, GsAppQuirk quirk)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+
+	return (priv->quirk & quirk) > 0;
+}
+
+/**
+ * gs_app_add_quirk:
+ * @app: a #GsApp
+ * @quirk: a #GsAppQuirk, e.g. %GS_APP_QUIRK_COMPULSORY
+ *
+ * Adds a quirk to an application.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_add_quirk (GsApp *app, GsAppQuirk quirk)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+
+	/* same */
+	if ((priv->quirk & quirk) > 0)
+		return;
+
+	locker = g_mutex_locker_new (&priv->mutex);
+	priv->quirk |= quirk;
+	gs_app_queue_notify (app, obj_props[PROP_QUIRK]);
+}
+
+/**
+ * gs_app_remove_quirk:
+ * @app: a #GsApp
+ * @quirk: a #GsAppQuirk, e.g. %GS_APP_QUIRK_COMPULSORY
+ *
+ * Removes a quirk from an application.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_remove_quirk (GsApp *app, GsAppQuirk quirk)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+
+	/* same */
+	if ((priv->quirk & quirk) == 0)
+		return;
+
+	locker = g_mutex_locker_new (&priv->mutex);
+	priv->quirk &= ~quirk;
+	gs_app_queue_notify (app, obj_props[PROP_QUIRK]);
+}
+
+/**
+ * gs_app_set_match_value:
+ * @app: a #GsApp
+ * @match_value: a value
+ *
+ * Set a match quality value, where higher values correspond to a
+ * "better" search match, and should be shown above lower results.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_match_value (GsApp *app, guint match_value)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_if_fail (GS_IS_APP (app));
+	priv->match_value = match_value;
+}
+
+/**
+ * gs_app_get_match_value:
+ * @app: a #GsApp
+ *
+ * Get a match quality value, where higher values correspond to a
+ * "better" search match, and should be shown above lower results.
+ *
+ * Note: This value is only valid when processing the result set
+ * and may be overwritten on subsequent searches if the plugin is using
+ * a cache.
+ *
+ * Returns: a value, where higher is better
+ *
+ * Since: 3.22
+ **/
+guint
+gs_app_get_match_value (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), 0);
+	return priv->match_value;
+}
+
+/**
+ * gs_app_set_priority:
+ * @app: a #GsApp
+ * @priority: a value
+ *
+ * Set a priority value.
+ *
+ * Since: 3.22
+ **/
+void
+gs_app_set_priority (GsApp *app, guint priority)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_if_fail (GS_IS_APP (app));
+	priv->priority = priority;
+}
+
+/**
+ * gs_app_get_priority:
+ * @app: a #GsApp
+ *
+ * Get a priority value, where higher values will be chosen where
+ * multiple #GsApp's match a specific rule.
+ *
+ * Returns: a value, where higher is better
+ *
+ * Since: 3.22
+ **/
+guint
+gs_app_get_priority (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_return_val_if_fail (GS_IS_APP (app), 0);
+
+	/* If the priority hasn’t been explicitly set, fetch it from the app’s
+	 * management plugin. */
+	if (priv->priority == 0) {
+		g_autoptr(GsPlugin) plugin = gs_app_dup_management_plugin (app);
+		if (plugin != NULL)
+			priv->priority = gs_plugin_get_priority (plugin);
+	}
+
+	return priv->priority;
+}
+
+/**
+ * gs_app_get_cancellable:
+ * @app: a #GsApp
+ *
+ * Get a cancellable to be used with operations related to the #GsApp. This is a
+ * way for views to be able to cancel an on-going operation. If the #GCancellable
+ * is canceled, it will be unreferenced and renewed before returning it, i.e. the
+ * cancellable object will always be ready to use for new operations. So be sure
+ * to keep a reference to it if you do more than just passing the cancellable to
+ * a process.
+ *
+ * Returns: a #GCancellable
+ *
+ * Since: 3.28
+ **/
+GCancellable *
+gs_app_get_cancellable (GsApp *app)
+{
+	g_autoptr(GCancellable) cancellable = NULL;
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	if (priv->cancellable == NULL || g_cancellable_is_cancelled (priv->cancellable)) {
+		cancellable = g_cancellable_new ();
+		g_set_object (&priv->cancellable, cancellable);
+	}
+	return priv->cancellable;
+}
+
+/**
+ * gs_app_get_pending_action:
+ * @app: a #GsApp
+ *
+ * Get the pending action for this #GsApp, or %NULL if no action is pending.
+ *
+ * Returns: the #GsAppAction of the @app.
+ **/
+GsPluginAction
+gs_app_get_pending_action (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_val_if_fail (GS_IS_APP (app), GS_PLUGIN_ACTION_UNKNOWN);
+	locker = g_mutex_locker_new (&priv->mutex);
+	return priv->pending_action;
+}
+
+/**
+ * gs_app_set_pending_action:
+ * @app: a #GsApp
+ * @action: a #GsPluginAction
+ *
+ * Set an action that is pending on this #GsApp.
+ **/
+void
+gs_app_set_pending_action (GsApp *app,
+			   GsPluginAction action)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	locker = g_mutex_locker_new (&priv->mutex);
+	gs_app_set_pending_action_internal (app, action);
+}
+
+static void
+gs_app_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
+{
+	GsApp *app = GS_APP (object);
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	switch ((GsAppProperty) prop_id) {
+	case PROP_ID:
+		g_value_set_string (value, priv->id);
+		break;
+	case PROP_NAME:
+		g_value_set_string (value, priv->name);
+		break;
+	case PROP_VERSION:
+		g_value_set_string (value, priv->version);
+		break;
+	case PROP_SUMMARY:
+		g_value_set_string (value, priv->summary);
+		break;
+	case PROP_DESCRIPTION:
+		g_value_set_string (value, priv->description);
+		break;
+	case PROP_RATING:
+		g_value_set_int (value, priv->rating);
+		break;
+	case PROP_KIND:
+		g_value_set_uint (value, priv->kind);
+		break;
+	case PROP_SPECIAL_KIND:
+		g_value_set_enum (value, priv->special_kind);
+		break;
+	case PROP_STATE:
+		g_value_set_enum (value, priv->state);
+		break;
+	case PROP_PROGRESS:
+		g_value_set_uint (value, priv->progress);
+		break;
+	case PROP_CAN_CANCEL_INSTALLATION:
+		g_value_set_boolean (value, priv->allow_cancel);
+		break;
+	case PROP_INSTALL_DATE:
+		g_value_set_uint64 (value, priv->install_date);
+		break;
+	case PROP_RELEASE_DATE:
+		g_value_set_uint64 (value, priv->release_date);
+		break;
+	case PROP_QUIRK:
+		g_value_set_flags (value, priv->quirk);
+		break;
+	case PROP_PENDING_ACTION:
+		g_value_set_enum (value, priv->pending_action);
+		break;
+	case PROP_KEY_COLORS:
+		g_value_set_boxed (value, gs_app_get_key_colors (app));
+		break;
+	case PROP_IS_UPDATE_DOWNLOADED:
+		g_value_set_boolean (value, priv->is_update_downloaded);
+		break;
+	case PROP_URLS:
+		g_value_set_boxed (value, priv->urls);
+		break;
+	case PROP_URL_MISSING:
+		g_value_set_string (value, priv->url_missing);
+		break;
+	case PROP_CONTENT_RATING:
+		g_value_set_object (value, priv->content_rating);
+		break;
+	case PROP_LICENSE:
+		g_value_set_string (value, priv->license);
+		break;
+	case PROP_SIZE_CACHE_DATA_TYPE:
+		g_value_set_enum (value, gs_app_get_size_cache_data (app, NULL));
+		break;
+	case PROP_SIZE_CACHE_DATA: {
+		guint64 size_bytes;
+		gs_app_get_size_cache_data (app, &size_bytes);
+		g_value_set_uint64 (value, size_bytes);
+		break;
+	}
+	case PROP_SIZE_DOWNLOAD_TYPE:
+		g_value_set_enum (value, gs_app_get_size_download (app, NULL));
+		break;
+	case PROP_SIZE_DOWNLOAD: {
+		guint64 size_bytes;
+		gs_app_get_size_download (app, &size_bytes);
+		g_value_set_uint64 (value, size_bytes);
+		break;
+	}
+	case PROP_SIZE_DOWNLOAD_DEPENDENCIES_TYPE:
+		g_value_set_enum (value, gs_app_get_size_download_dependencies (app, NULL));
+		break;
+	case PROP_SIZE_DOWNLOAD_DEPENDENCIES: {
+		guint64 size_bytes;
+		gs_app_get_size_download_dependencies (app, &size_bytes);
+		g_value_set_uint64 (value, size_bytes);
+		break;
+	}
+	case PROP_SIZE_INSTALLED_TYPE:
+		g_value_set_enum (value, gs_app_get_size_installed (app, NULL));
+		break;
+	case PROP_SIZE_INSTALLED: {
+		guint64 size_bytes;
+		gs_app_get_size_installed (app, &size_bytes);
+		g_value_set_uint64 (value, size_bytes);
+		break;
+	}
+	case PROP_SIZE_INSTALLED_DEPENDENCIES_TYPE:
+		g_value_set_enum (value, gs_app_get_size_installed_dependencies (app, NULL));
+		break;
+	case PROP_SIZE_INSTALLED_DEPENDENCIES: {
+		guint64 size_bytes;
+		gs_app_get_size_installed_dependencies (app, &size_bytes);
+		g_value_set_uint64 (value, size_bytes);
+		break;
+	}
+	case PROP_SIZE_USER_DATA_TYPE:
+		g_value_set_enum (value, gs_app_get_size_user_data (app, NULL));
+		break;
+	case PROP_SIZE_USER_DATA: {
+		guint64 size_bytes;
+		gs_app_get_size_user_data (app, &size_bytes);
+		g_value_set_uint64 (value, size_bytes);
+		break;
+	}
+	case PROP_PERMISSIONS:
+		g_value_take_object (value, gs_app_dup_permissions (app));
+		break;
+	case PROP_RELATIONS:
+		g_value_take_boxed (value, gs_app_get_relations (app));
+		break;
+	case PROP_ORIGIN_UI:
+		g_value_take_string (value, gs_app_dup_origin_ui (app, TRUE));
+		break;
+	case PROP_HAS_TRANSLATIONS:
+		g_value_set_boolean (value, gs_app_get_has_translations (app));
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_app_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
+{
+	GsApp *app = GS_APP (object);
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	switch ((GsAppProperty) prop_id) {
+	case PROP_ID:
+		gs_app_set_id (app, g_value_get_string (value));
+		break;
+	case PROP_NAME:
+		gs_app_set_name (app,
+				 GS_APP_QUALITY_UNKNOWN,
+				 g_value_get_string (value));
+		break;
+	case PROP_VERSION:
+		gs_app_set_version (app, g_value_get_string (value));
+		break;
+	case PROP_SUMMARY:
+		gs_app_set_summary (app,
+				    GS_APP_QUALITY_UNKNOWN,
+				    g_value_get_string (value));
+		break;
+	case PROP_DESCRIPTION:
+		gs_app_set_description (app,
+					GS_APP_QUALITY_UNKNOWN,
+					g_value_get_string (value));
+		break;
+	case PROP_RATING:
+		gs_app_set_rating (app, g_value_get_int (value));
+		break;
+	case PROP_KIND:
+		gs_app_set_kind (app, g_value_get_uint (value));
+		break;
+	case PROP_SPECIAL_KIND:
+		gs_app_set_special_kind (app, g_value_get_enum (value));
+		break;
+	case PROP_STATE:
+		gs_app_set_state_internal (app, g_value_get_enum (value));
+		break;
+	case PROP_PROGRESS:
+		gs_app_set_progress (app, g_value_get_uint (value));
+		break;
+	case PROP_CAN_CANCEL_INSTALLATION:
+		priv->allow_cancel = g_value_get_boolean (value);
+		break;
+	case PROP_INSTALL_DATE:
+		gs_app_set_install_date (app, g_value_get_uint64 (value));
+		break;
+	case PROP_RELEASE_DATE:
+		gs_app_set_release_date (app, g_value_get_uint64 (value));
+		break;
+	case PROP_QUIRK:
+		priv->quirk = g_value_get_flags (value);
+		break;
+	case PROP_PENDING_ACTION:
+		/* Read only */
+		g_assert_not_reached ();
+		break;
+	case PROP_KEY_COLORS:
+		gs_app_set_key_colors (app, g_value_get_boxed (value));
+		break;
+	case PROP_IS_UPDATE_DOWNLOADED:
+		gs_app_set_is_update_downloaded (app, g_value_get_boolean (value));
+		break;
+	case PROP_URLS:
+		/* Read only */
+		g_assert_not_reached ();
+		break;
+	case PROP_URL_MISSING:
+		gs_app_set_url_missing (app, g_value_get_string (value));
+		break;
+	case PROP_CONTENT_RATING:
+		gs_app_set_content_rating (app, g_value_get_object (value));
+		break;
+	case PROP_LICENSE:
+		/* Read-only */
+		g_assert_not_reached ();
+	case PROP_SIZE_CACHE_DATA_TYPE:
+		gs_app_set_size_cache_data (app, g_value_get_enum (value), priv->size_cache_data);
+		break;
+	case PROP_SIZE_CACHE_DATA:
+		gs_app_set_size_cache_data (app, priv->size_cache_data_type, g_value_get_uint64 (value));
+		break;
+	case PROP_SIZE_DOWNLOAD_TYPE:
+		gs_app_set_size_download (app, g_value_get_enum (value), priv->size_download);
+		break;
+	case PROP_SIZE_DOWNLOAD:
+		gs_app_set_size_download (app, priv->size_download_type, g_value_get_uint64 (value));
+		break;
+	case PROP_SIZE_DOWNLOAD_DEPENDENCIES_TYPE:
+	case PROP_SIZE_DOWNLOAD_DEPENDENCIES:
+		/* Read-only */
+		g_assert_not_reached ();
+	case PROP_SIZE_INSTALLED_TYPE:
+		gs_app_set_size_installed (app, g_value_get_enum (value), priv->size_installed);
+		break;
+	case PROP_SIZE_INSTALLED:
+		gs_app_set_size_installed (app, priv->size_installed_type, g_value_get_uint64 (value));
+		break;
+	case PROP_SIZE_INSTALLED_DEPENDENCIES_TYPE:
+	case PROP_SIZE_INSTALLED_DEPENDENCIES:
+		/* Read-only */
+		g_assert_not_reached ();
+	case PROP_SIZE_USER_DATA_TYPE:
+		gs_app_set_size_user_data (app, g_value_get_enum (value), priv->size_user_data);
+		break;
+	case PROP_SIZE_USER_DATA:
+		gs_app_set_size_user_data (app, priv->size_user_data_type, g_value_get_uint64 (value));
+		break;
+	case PROP_PERMISSIONS:
+		gs_app_set_permissions (app, g_value_get_object (value));
+		break;
+	case PROP_RELATIONS:
+		gs_app_set_relations (app, g_value_get_boxed (value));
+		break;
+	case PROP_ORIGIN_UI:
+		gs_app_set_origin_ui (app, g_value_get_string (value));
+		break;
+	case PROP_HAS_TRANSLATIONS:
+		gs_app_set_has_translations (app, g_value_get_boolean (value));
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_app_dispose (GObject *object)
+{
+	GsApp *app = GS_APP (object);
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	g_clear_object (&priv->runtime);
+
+	g_clear_pointer (&priv->addons, g_object_unref);
+	g_clear_pointer (&priv->history, g_object_unref);
+	g_clear_pointer (&priv->related, g_object_unref);
+	g_clear_pointer (&priv->screenshots, g_ptr_array_unref);
+	g_clear_pointer (&priv->review_ratings, g_array_unref);
+	g_clear_pointer (&priv->reviews, g_ptr_array_unref);
+	g_clear_pointer (&priv->provided, g_ptr_array_unref);
+	g_clear_pointer (&priv->icons, g_ptr_array_unref);
+	g_clear_pointer (&priv->version_history, g_ptr_array_unref);
+	g_clear_pointer (&priv->relations, g_ptr_array_unref);
+	g_weak_ref_clear (&priv->management_plugin_weak);
+
+	G_OBJECT_CLASS (gs_app_parent_class)->dispose (object);
+}
+
+static void
+gs_app_finalize (GObject *object)
+{
+	GsApp *app = GS_APP (object);
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	g_mutex_clear (&priv->mutex);
+	g_free (priv->id);
+	g_free (priv->unique_id);
+	g_free (priv->branch);
+	g_free (priv->name);
+	g_free (priv->renamed_from);
+	g_free (priv->url_missing);
+	g_clear_pointer (&priv->urls, g_hash_table_unref);
+	g_hash_table_unref (priv->launchables);
+	g_free (priv->license);
+	g_strfreev (priv->menu_path);
+	g_free (priv->origin);
+	g_free (priv->origin_ui);
+	g_free (priv->origin_appstream);
+	g_free (priv->origin_hostname);
+	g_ptr_array_unref (priv->sources);
+	g_ptr_array_unref (priv->source_ids);
+	g_free (priv->project_group);
+	g_free (priv->developer_name);
+	g_free (priv->agreement);
+	g_free (priv->version);
+	g_free (priv->version_ui);
+	g_free (priv->summary);
+	g_free (priv->summary_missing);
+	g_free (priv->description);
+	g_free (priv->update_version);
+	g_free (priv->update_version_ui);
+	g_free (priv->update_details_markup);
+	g_hash_table_unref (priv->metadata);
+	g_ptr_array_unref (priv->categories);
+	g_clear_pointer (&priv->key_colors, g_array_unref);
+	g_clear_object (&priv->cancellable);
+	g_clear_object (&priv->local_file);
+	g_clear_object (&priv->content_rating);
+	g_clear_object (&priv->action_screenshot);
+	g_clear_object (&priv->update_permissions);
+	g_clear_object (&priv->permissions);
+
+	G_OBJECT_CLASS (gs_app_parent_class)->finalize (object);
+}
+
+static void
+gs_app_class_init (GsAppClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+	object_class->dispose = gs_app_dispose;
+	object_class->finalize = gs_app_finalize;
+	object_class->get_property = gs_app_get_property;
+	object_class->set_property = gs_app_set_property;
+
+	/**
+	 * GsApp:id:
+	 */
+	obj_props[PROP_ID] = g_param_spec_string ("id", NULL, NULL,
+				     NULL,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:name:
+	 */
+	obj_props[PROP_NAME] = g_param_spec_string ("name", NULL, NULL,
+				     NULL,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:version:
+	 */
+	obj_props[PROP_VERSION] = g_param_spec_string ("version", NULL, NULL,
+				     NULL,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:summary:
+	 */
+	obj_props[PROP_SUMMARY] = g_param_spec_string ("summary", NULL, NULL,
+				     NULL,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:description:
+	 */
+	obj_props[PROP_DESCRIPTION] = g_param_spec_string ("description", NULL, NULL,
+				     NULL,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:rating:
+	 */
+	obj_props[PROP_RATING] = g_param_spec_int ("rating", NULL, NULL,
+				  -1, 100, -1,
+				  G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:kind:
+	 */
+	/* FIXME: Should use AS_TYPE_APP_KIND when it’s available */
+	obj_props[PROP_KIND] = g_param_spec_uint ("kind", NULL, NULL,
+				   AS_COMPONENT_KIND_UNKNOWN,
+				   AS_COMPONENT_KIND_LAST,
+				   AS_COMPONENT_KIND_UNKNOWN,
+				   G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:special-kind:
+	 *
+	 * GNOME Software specific occupation of the #GsApp entity
+	 * that does not reflect a software type defined by AppStream.
+	 *
+	 * Since: 40
+	 */
+	obj_props[PROP_SPECIAL_KIND] = g_param_spec_enum ("special-kind", NULL, NULL,
+					GS_TYPE_APP_SPECIAL_KIND,
+					GS_APP_SPECIAL_KIND_NONE,
+					G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:state:
+	 */
+	obj_props[PROP_STATE] = g_param_spec_enum ("state", NULL, NULL,
+				   GS_TYPE_APP_STATE,
+				   GS_APP_STATE_UNKNOWN,
+				   G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:progress:
+	 *
+	 * A percentage (0–100, inclusive) indicating the progress through the
+	 * current task on this app. The value may otherwise be
+	 * %GS_APP_PROGRESS_UNKNOWN if the progress is unknown or has a wide
+	 * confidence interval.
+	 */
+	obj_props[PROP_PROGRESS] = g_param_spec_uint ("progress", NULL, NULL,
+				   0, GS_APP_PROGRESS_UNKNOWN, GS_APP_PROGRESS_UNKNOWN,
+				   G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:allow-cancel:
+	 */
+	obj_props[PROP_CAN_CANCEL_INSTALLATION] =
+		g_param_spec_boolean ("allow-cancel", NULL, NULL, TRUE,
+				      G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:install-date:
+	 */
+	obj_props[PROP_INSTALL_DATE] = g_param_spec_uint64 ("install-date", NULL, NULL,
+				     0, G_MAXUINT64, 0,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:release-date:
+	 *
+	 * Set to the release date of the application on the server. Can be 0,
+	 * which means the release date is unknown.
+	 *
+	 * Since: 3.40
+	 */
+	obj_props[PROP_RELEASE_DATE] = g_param_spec_uint64 ("release-date", NULL, NULL,
+				     0, G_MAXUINT64, 0,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:quirk:
+	 */
+	obj_props[PROP_QUIRK] = g_param_spec_flags ("quirk", NULL, NULL,
+				     GS_TYPE_APP_QUIRK, GS_APP_QUIRK_NONE,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:pending-action:
+	 */
+	obj_props[PROP_PENDING_ACTION] = g_param_spec_enum ("pending-action", NULL, NULL,
+				     GS_TYPE_PLUGIN_ACTION, GS_PLUGIN_ACTION_UNKNOWN,
+				     G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:key-colors:
+	 */
+	obj_props[PROP_KEY_COLORS] = g_param_spec_boxed ("key-colors", NULL, NULL,
+				    G_TYPE_ARRAY, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:is-update-downloaded:
+	 */
+	obj_props[PROP_IS_UPDATE_DOWNLOADED] = g_param_spec_boolean ("is-update-downloaded", NULL, NULL,
+					       FALSE,
+					       G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:urls: (nullable) (element-type AsUrlKind utf8)
+	 *
+	 * The URLs associated with the app.
+	 *
+	 * This is %NULL if no URLs are available. If provided, it is a mapping
+	 * from #AsUrlKind to the URLs.
+	 *
+	 * This property is read-only: use gs_app_set_url() to set URLs.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_URLS] =
+		g_param_spec_boxed ("urls", NULL, NULL,
+				    G_TYPE_HASH_TABLE,
+				    G_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:url-missing:
+	 *
+	 * A web URL pointing to explanations why this app
+	 * does not have an installation candidate.
+	 *
+	 * Since: 40
+	 */
+	obj_props[PROP_URL_MISSING] = g_param_spec_string ("url-missing", NULL, NULL,
+					NULL,
+					G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:content-rating: (nullable)
+	 *
+	 * The content rating for the app, which gives information on how
+	 * suitable it is for different age ranges of user.
+	 *
+	 * This is %NULL if no content rating information is available.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_CONTENT_RATING] =
+		g_param_spec_object ("content-rating", NULL, NULL,
+				     /* FIXME: Use the get_type() function directly here to work
+				      * around https://github.com/ximion/appstream/pull/318 */
+				     as_content_rating_get_type (),
+				     G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:license: (nullable)
+	 *
+	 * The license for the app, which is typically its source code license.
+	 *
+	 * Use gs_app_set_license() to set this.
+	 *
+	 * This is %NULL if no licensing information is available.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_LICENSE] =
+		g_param_spec_string ("license", NULL, NULL,
+				     NULL,
+				     G_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:size-cache-data-type
+	 *
+	 * The type of #GsApp:size-cache-data.
+	 *
+	 * Since: 43
+	 */
+	obj_props[PROP_SIZE_CACHE_DATA_TYPE] =
+		g_param_spec_enum ("size-cache-data-type", NULL, NULL,
+				   GS_TYPE_SIZE_TYPE, GS_SIZE_TYPE_UNKNOWN,
+				   G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:size-cache-data
+	 *
+	 * The size on the disk for the cache data of the application.
+	 *
+	 * This is undefined if #GsApp:size-cache-data-type is not
+	 * %GS_SIZE_TYPE_VALID.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_SIZE_CACHE_DATA] =
+		g_param_spec_uint64 ("size-cache-data", NULL, NULL,
+				     0, G_MAXUINT64, 0,
+				     G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:size-download-type
+	 *
+	 * The type of #GsApp:size-download.
+	 *
+	 * Since: 43
+	 */
+	obj_props[PROP_SIZE_DOWNLOAD_TYPE] =
+		g_param_spec_enum ("size-download-type", NULL, NULL,
+				   GS_TYPE_SIZE_TYPE, GS_SIZE_TYPE_UNKNOWN,
+				   G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:size-download
+	 *
+	 * The size of the total download needed to either install or update
+	 * this application, in bytes. If the app is partially downloaded, this
+	 * is the number of bytes remaining to download.
+	 *
+	 * This is undefined if #GsApp:size-download-type is not
+	 * %GS_SIZE_TYPE_VALID.
+	 *
+	 * To get the runtime or other dependencies download size,
+	 * use #GsApp:size-download-dependencies.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_SIZE_DOWNLOAD] =
+		g_param_spec_uint64 ("size-download", NULL, NULL,
+				     0, G_MAXUINT64, 0,
+				     G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:size-download-dependencies-type
+	 *
+	 * The type of #GsApp:size-download-dependencies.
+	 *
+	 * Since: 43
+	 */
+	obj_props[PROP_SIZE_DOWNLOAD_DEPENDENCIES_TYPE] =
+		g_param_spec_enum ("size-download-dependencies-type", NULL, NULL,
+				   GS_TYPE_SIZE_TYPE, GS_SIZE_TYPE_UNKNOWN,
+				   G_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:size-download-dependencies
+	 *
+	 * The size of the total download needed to either install or update
+	 * this application's dependencies, in bytes. If the dependencies are partially
+	 * downloaded, this is the number of bytes remaining to download.
+	 *
+	 * This is undefined if #GsApp:size-download-dependencies-type is not
+	 * %GS_SIZE_TYPE_VALID.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_SIZE_DOWNLOAD_DEPENDENCIES] =
+		g_param_spec_uint64 ("size-download-dependencies", NULL, NULL,
+				     0, G_MAXUINT64, 0,
+				     G_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:size-installed-type
+	 *
+	 * The type of #GsApp:size-installed.
+	 *
+	 * Since: 43
+	 */
+	obj_props[PROP_SIZE_INSTALLED_TYPE] =
+		g_param_spec_enum ("size-installed-type", NULL, NULL,
+				   GS_TYPE_SIZE_TYPE, GS_SIZE_TYPE_UNKNOWN,
+				   G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:size-installed
+	 *
+	 * The size of the application on disk, in bytes. If the application is
+	 * not yet installed, this is the size it would need, once installed.
+	 *
+	 * This is undefined if #GsApp:size-installed-type is not
+	 * %GS_SIZE_TYPE_VALID.
+	 *
+	 * To get the application runtime or extensions installed sizes,
+	 * use #GsApp:size-installed-dependencies.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_SIZE_INSTALLED] =
+		g_param_spec_uint64 ("size-installed", NULL, NULL,
+				     0, G_MAXUINT64, 0,
+				     G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:size-installed-dependencies-type
+	 *
+	 * The type of #GsApp:size-installed-dependencies.
+	 *
+	 * Since: 43
+	 */
+	obj_props[PROP_SIZE_INSTALLED_DEPENDENCIES_TYPE] =
+		g_param_spec_enum ("size-installed-dependencies-type", NULL, NULL,
+				   GS_TYPE_SIZE_TYPE, GS_SIZE_TYPE_UNKNOWN,
+				   G_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:size-installed-dependencies
+	 *
+	 * The size of the application's dependencies on disk, in bytes. If the dependencies are
+	 * not yet installed, this is the size it would need, once installed.
+	 *
+	 * This is undefined if #GsApp:size-installed-dependencies-type is not
+	 * %GS_SIZE_TYPE_VALID.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_SIZE_INSTALLED_DEPENDENCIES] =
+		g_param_spec_uint64 ("size-installed-dependencies", NULL, NULL,
+				     0, G_MAXUINT64, 0,
+				     G_PARAM_READABLE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:size-user-data-type
+	 *
+	 * The type of #GsApp:size-user-data.
+	 *
+	 * Since: 43
+	 */
+	obj_props[PROP_SIZE_USER_DATA_TYPE] =
+		g_param_spec_enum ("size-user-data-type", NULL, NULL,
+				   GS_TYPE_SIZE_TYPE, GS_SIZE_TYPE_UNKNOWN,
+				   G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:size-user-data
+	 *
+	 * The size on the disk for the user data of the application.
+	 *
+	 * This is undefined if #GsApp:size-user-data-type is not
+	 * %GS_SIZE_TYPE_VALID.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_SIZE_USER_DATA] =
+		g_param_spec_uint64 ("size-user-data", NULL, NULL,
+				     0, G_MAXUINT64, 0,
+				     G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:permissions
+	 *
+	 * The permissions the app requires to run, as a #GsAppPermissions object.
+	 *
+	 * This is %NULL, if the permissions are unknown.
+	 *
+	 * Since: 43
+	 */
+	obj_props[PROP_PERMISSIONS] =
+		g_param_spec_object ("permissions", NULL, NULL,
+				     GS_TYPE_APP_PERMISSIONS,
+				     G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:relations: (nullable) (element-type AsRelation)
+	 *
+	 * Relations between this app and other things. For example,
+	 * requirements or recommendations that the computer have certain input
+	 * devices to use the app (the app requires a touchscreen or gamepad),
+	 * or that the screen is a certain size.
+	 *
+	 * %NULL is equivalent to an empty array. Relations of kind
+	 * %AS_RELATION_KIND_REQUIRES are conjunctive, so each additional
+	 * relation further restricts the set of computers which can run the
+	 * app. Relations of kind %AS_RELATION_KIND_RECOMMENDS and
+	 * %AS_RELATION_KIND_SUPPORTS are disjunctive.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_RELATIONS] =
+		g_param_spec_boxed ("relations", NULL, NULL,
+				    G_TYPE_PTR_ARRAY,
+				    G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:origin-ui: (not nullable)
+	 *
+	 * The package origin, in a human readable format suitable for use in
+	 * the UI. For example ‘Local file (RPM)’ or ‘Flathub (Flatpak)’.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_ORIGIN_UI] =
+		g_param_spec_string ("origin-ui", NULL, NULL,
+				     NULL,
+				     G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsApp:has-translations
+	 *
+	 * Whether the app has any information about provided translations. If
+	 * this is %TRUE, the app provides information about the translations
+	 * it ships. If %FALSE, the app does not provide any information (but
+	 * might ship translations which aren’t mentioned).
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_HAS_TRANSLATIONS] =
+		g_param_spec_boolean ("has-translations", NULL, NULL,
+				      FALSE,
+				      G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	g_object_class_install_properties (object_class, G_N_ELEMENTS (obj_props), obj_props);
+}
+
+static void
+gs_app_init (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	priv->rating = -1;
+	priv->sources = g_ptr_array_new_with_free_func (g_free);
+	priv->source_ids = g_ptr_array_new_with_free_func (g_free);
+	priv->categories = g_ptr_array_new_with_free_func (g_free);
+	priv->related = gs_app_list_new ();
+	priv->history = gs_app_list_new ();
+	priv->screenshots = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);
+	priv->reviews = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);
+	priv->provided = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);
+	priv->metadata = g_hash_table_new_full (g_str_hash,
+	                                        g_str_equal,
+	                                        g_free,
+	                                        (GDestroyNotify) g_variant_unref);
+	priv->launchables = g_hash_table_new_full (g_str_hash,
+	                                           g_str_equal,
+	                                           NULL,
+	                                           g_free);
+	priv->allow_cancel = TRUE;
+	priv->size_download_type = GS_SIZE_TYPE_UNKNOWN;
+	priv->size_installed_type = GS_SIZE_TYPE_UNKNOWN;
+	priv->size_cache_data_type = GS_SIZE_TYPE_UNKNOWN;
+	priv->size_user_data_type = GS_SIZE_TYPE_UNKNOWN;
+	g_mutex_init (&priv->mutex);
+}
+
+/**
+ * gs_app_new:
+ * @id: an application ID, or %NULL, e.g. "org.gnome.Software.desktop"
+ *
+ * Creates a new application object.
+ *
+ * The ID should only be set when the application ID (with optional prefix) is
+ * known; it is perfectly valid to use gs_app_new() with an @id of %NULL, and
+ * then relying on another plugin to set the @id using gs_app_set_id() based on
+ * some other information.
+ *
+ * For instance, a #GsApp is created with no ID when returning results from the
+ * packagekit plugin, but with the default source name set as the package name.
+ * The source name is read by the appstream plugin, and if matched in the
+ * AppStream XML the correct ID is set, along with other higher quality data
+ * like the application icon and long description.
+ *
+ * Returns: a new #GsApp
+ *
+ * Since: 3.22
+ **/
+GsApp *
+gs_app_new (const gchar *id)
+{
+	GsApp *app;
+	app = g_object_new (GS_TYPE_APP,
+			    "id", id,
+			    NULL);
+	return GS_APP (app);
+}
+
+/**
+ * gs_app_set_from_unique_id:
+ * @app: a #GsApp
+ * @unique_id: an application unique ID, e.g.
+ *	`system/flatpak/gnome/desktop/org.gnome.Software.desktop/master`
+ *
+ * Sets details on an application object.
+ *
+ * The unique ID will be parsed to set some information in the application such
+ * as the scope, bundle kind, id, etc.
+ *
+ * Since: 3.26
+ **/
+void
+gs_app_set_from_unique_id (GsApp *app, const gchar *unique_id, AsComponentKind kind)
+{
+	g_auto(GStrv) split = NULL;
+
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (unique_id != NULL);
+
+	if (kind != AS_COMPONENT_KIND_UNKNOWN)
+		gs_app_set_kind (app, kind);
+
+	split = g_strsplit (unique_id, "/", -1);
+	if (g_strv_length (split) != 5)
+		return;
+	if (g_strcmp0 (split[0], "*") != 0)
+		gs_app_set_scope (app, as_component_scope_from_string (split[0]));
+	if (g_strcmp0 (split[1], "*") != 0)
+		gs_app_set_bundle_kind (app, as_bundle_kind_from_string (split[1]));
+	if (g_strcmp0 (split[2], "*") != 0)
+		gs_app_set_origin (app, split[2]);
+	if (g_strcmp0 (split[3], "*") != 0)
+		gs_app_set_id (app, split[3]);
+	if (g_strcmp0 (split[4], "*") != 0)
+		gs_app_set_branch (app, split[4]);
+}
+
+/**
+ * gs_app_new_from_unique_id:
+ * @unique_id: an application unique ID, e.g.
+ *	`system/flatpak/gnome/desktop/org.gnome.Software.desktop/master`
+ *
+ * Creates a new application object.
+ *
+ * The unique ID will be parsed to set some information in the application such
+ * as the scope, bundle kind, id, etc. Unlike gs_app_new(), it cannot take a
+ * %NULL argument.
+ *
+ * Returns: a new #GsApp
+ *
+ * Since: 3.22
+ **/
+GsApp *
+gs_app_new_from_unique_id (const gchar *unique_id)
+{
+	GsApp *app;
+	g_return_val_if_fail (unique_id != NULL, NULL);
+	app = gs_app_new (NULL);
+	gs_app_set_from_unique_id (app, unique_id, AS_COMPONENT_KIND_UNKNOWN);
+	return app;
+}
+
+/**
+ * gs_app_dup_origin_ui:
+ * @app: a #GsApp
+ * @with_packaging_format: %TRUE, to include also packaging format
+ *
+ * Gets the package origin that's suitable for UI use, i.e. the value of
+ * #GsApp:origin-ui.
+ *
+ * Returns: (not nullable) (transfer full): The package origin for UI use
+ *
+ * Since: 43
+ **/
+gchar *
+gs_app_dup_origin_ui (GsApp *app,
+		      gboolean with_packaging_format)
+{
+	GsAppPrivate *priv;
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_autoptr(GsOsRelease) os_release = NULL;
+	const gchar *origin_str = NULL;
+
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+
+	/* use the distro name for official packages */
+	if (gs_app_has_quirk (app, GS_APP_QUIRK_PROVENANCE) &&
+	    gs_app_get_kind (app) != AS_COMPONENT_KIND_REPOSITORY) {
+		os_release = gs_os_release_new (NULL);
+		if (os_release != NULL)
+			origin_str = gs_os_release_get_name (os_release);
+	}
+
+	priv = gs_app_get_instance_private (app);
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	if (!origin_str) {
+		origin_str = priv->origin_ui;
+
+		if (origin_str == NULL || origin_str[0] == '\0') {
+			/* use "Local file" rather than the filename for local files */
+			if (gs_app_get_state (app) == GS_APP_STATE_AVAILABLE_LOCAL ||
+			    gs_app_get_local_file (app) != NULL)
+				origin_str = _("Local file");
+			else if (g_strcmp0 (gs_app_get_origin (app), "flathub") == 0)
+				origin_str = "Flathub";
+			else if (g_strcmp0 (gs_app_get_origin (app), "flathub-beta") == 0)
+				origin_str = "Flathub Beta";
+			else
+				origin_str = gs_app_get_origin (app);
+		}
+	}
+
+	if (with_packaging_format) {
+		g_autofree gchar *packaging_format = NULL;
+
+		packaging_format = gs_app_get_packaging_format (app);
+
+		if (packaging_format) {
+			/* TRANSLATORS: the first %s is replaced with an origin name;
+			   the second %s is replaced with the packaging format.
+			   Example string: "Local file (RPM)" */
+			return g_strdup_printf (_("%s (%s)"), origin_str, packaging_format);
+		}
+	}
+
+	return g_strdup (origin_str);
+}
+
+/**
+ * gs_app_set_origin_ui:
+ * @app: a #GsApp
+ * @origin_ui: (not nullable): the new origin UI
+ *
+ * Set the value of #GsApp:origin-ui.
+ */
+void
+gs_app_set_origin_ui (GsApp *app,
+		      const gchar *origin_ui)
+{
+	GsAppPrivate *priv;
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_APP (app));
+
+	priv = gs_app_get_instance_private (app);
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	if (origin_ui && !*origin_ui)
+		origin_ui = NULL;
+
+	if (g_strcmp0 (priv->origin_ui, origin_ui) == 0)
+		return;
+
+	g_free (priv->origin_ui);
+	priv->origin_ui = g_strdup (origin_ui);
+	gs_app_queue_notify (app, obj_props[PROP_ORIGIN_UI]);
+}
+
+/**
+ * gs_app_get_packaging_format:
+ * @app: a #GsApp
+ *
+ * Gets the packaging format, e.g. 'RPM' or 'Flatpak'.
+ *
+ * Returns: The packaging format
+ *
+ * Since: 3.32
+ **/
+gchar *
+gs_app_get_packaging_format (GsApp *app)
+{
+	AsBundleKind bundle_kind;
+	const gchar *bundle_kind_ui;
+	const gchar *packaging_format;
+
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+
+	/* does the app have packaging format set? */
+	packaging_format = gs_app_get_metadata_item (app, "GnomeSoftware::PackagingFormat");
+	if (packaging_format != NULL)
+		return g_strdup (packaging_format);
+
+	/* fall back to bundle kind */
+	bundle_kind = gs_app_get_bundle_kind (app);
+	switch (bundle_kind) {
+	case AS_BUNDLE_KIND_UNKNOWN:
+		bundle_kind_ui = NULL;
+		break;
+	case AS_BUNDLE_KIND_LIMBA:
+		bundle_kind_ui = "Limba";
+		break;
+	case AS_BUNDLE_KIND_FLATPAK:
+		bundle_kind_ui = "Flatpak";
+		break;
+	case AS_BUNDLE_KIND_SNAP:
+		bundle_kind_ui = "Snap";
+		break;
+	case AS_BUNDLE_KIND_PACKAGE:
+		bundle_kind_ui = _("Package");
+		break;
+	case AS_BUNDLE_KIND_CABINET:
+		bundle_kind_ui = "Cabinet";
+		break;
+	case AS_BUNDLE_KIND_APPIMAGE:
+		bundle_kind_ui = "AppImage";
+		break;
+	default:
+		g_warning ("unhandled bundle kind %s", as_bundle_kind_to_string (bundle_kind));
+		bundle_kind_ui = as_bundle_kind_to_string (bundle_kind);
+	}
+
+	return g_strdup (bundle_kind_ui);
+}
+
+/**
+ * gs_app_get_packaging_format_raw:
+ * @app: a #GsApp
+ *
+ * Similar to gs_app_get_packaging_format(), but it does not return a newly
+ * allocated string and the value is not suitable for the UI. Depending on
+ * the plugin, it can be "deb", "flatpak", "package", "RPM", "snap", ....
+ *
+ * Returns: The raw value of the packaging format
+ *
+ * Since: 41
+ **/
+const gchar *
+gs_app_get_packaging_format_raw (GsApp *app)
+{
+	const gchar *packaging_format;
+
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+
+	packaging_format = gs_app_get_metadata_item (app, "GnomeSoftware::PackagingFormat");
+	if (packaging_format != NULL)
+		return packaging_format;
+
+	return as_bundle_kind_to_string (gs_app_get_bundle_kind (app));
+}
+
+/**
+ * gs_app_subsume_metadata:
+ * @app: a #GsApp
+ * @donor: another #GsApp
+ *
+ * Copies any metadata from @donor to @app.
+ *
+ * Since: 3.32
+ **/
+void
+gs_app_subsume_metadata (GsApp *app, GsApp *donor)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (donor);
+	g_autoptr(GList) keys = NULL;
+
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (GS_IS_APP (donor));
+
+	keys = g_hash_table_get_keys (priv->metadata);
+	for (GList *l = keys; l != NULL; l = l->next) {
+		const gchar *key = l->data;
+		GVariant *tmp = gs_app_get_metadata_variant (donor, key);
+		if (gs_app_get_metadata_variant (app, key) != NULL)
+			continue;
+		gs_app_set_metadata_variant (app, key, tmp);
+	}
+}
+
+/**
+ * gs_app_dup_permissions:
+ * @app: a #GsApp
+ *
+ * Get a reference to the @app permissions. The returned value can
+ * be %NULL, when the app's permissions are unknown. Free the returned pointer,
+ * if not %NULL, with g_object_unref(), when no longer needed.
+ *
+ * Returns: (nullable) (transfer full): referenced #GsAppPermissions,
+ *    or %NULL
+ *
+ * Since: 43
+ **/
+GsAppPermissions *
+gs_app_dup_permissions (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	locker = g_mutex_locker_new (&priv->mutex);
+	return priv->permissions ? g_object_ref (priv->permissions) : NULL;
+}
+
+/**
+ * gs_app_set_permissions:
+ * @app: a #GsApp
+ * @permissions: (nullable) (transfer none): a #GsAppPermissions, or %NULL
+ *
+ * Set permissions for the @app. The @permissions is referenced,
+ * if not %NULL.
+ *
+ * Note the @permissions need to be sealed.
+ *
+ * Since: 43
+ **/
+void
+gs_app_set_permissions (GsApp *app,
+			GsAppPermissions *permissions)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (permissions == NULL || gs_app_permissions_is_sealed (permissions));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+	if (priv->permissions == permissions)
+		return;
+	g_clear_object (&priv->permissions);
+	if (permissions != NULL)
+		priv->permissions = g_object_ref (permissions);
+	gs_app_queue_notify (app, obj_props[PROP_PERMISSIONS]);
+}
+
+/**
+ * gs_app_dup_update_permissions:
+ * @app: a #GsApp
+ *
+ * Get a reference to the update permissions. The returned value can
+ * be %NULL, when no update permissions had been set. Free
+ * the returned pointer, if not %NULL, with g_object_unref(), when
+ * no longer needed.
+ *
+ * Returns: (nullable) (transfer full): referenced #GsAppPermissions,
+ *    or %NULL
+ *
+ * Since: 43
+ **/
+GsAppPermissions *
+gs_app_dup_update_permissions (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+	locker = g_mutex_locker_new (&priv->mutex);
+	return priv->update_permissions ? g_object_ref (priv->update_permissions) : NULL;
+}
+
+/**
+ * gs_app_set_update_permissions:
+ * @app: a #GsApp
+ * @update_permissions: (nullable) (transfer none): a #GsAppPermissions, or %NULL
+ *
+ * Set update permissions for the @app, that is, the permissions, which change
+ * in an update or similar reasons. The @update_permissions is referenced,
+ * if not %NULL.
+ *
+ * Note the @update_permissions need to be sealed.
+ *
+ * Since: 43
+ **/
+void
+gs_app_set_update_permissions (GsApp *app,
+			       GsAppPermissions *update_permissions)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (update_permissions == NULL || gs_app_permissions_is_sealed (update_permissions));
+	locker = g_mutex_locker_new (&priv->mutex);
+	if (priv->update_permissions != update_permissions) {
+		g_clear_object (&priv->update_permissions);
+		if (update_permissions != NULL)
+			priv->update_permissions = g_object_ref (update_permissions);
+	}
+}
+
+/**
+ * gs_app_get_version_history:
+ * @app: a #GsApp
+ *
+ * Gets the list of past releases for an application (including the latest
+ * one).
+ *
+ * Returns: (element-type AsRelease) (transfer container) (nullable): a list, or
+ *     %NULL if the version history is not known
+ *
+ * Since: 41
+ **/
+GPtrArray *
+gs_app_get_version_history (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+
+	locker = g_mutex_locker_new (&priv->mutex);
+	if (priv->version_history == NULL)
+		return NULL;
+	return g_ptr_array_ref (priv->version_history);
+}
+
+/**
+ * gs_app_set_version_history:
+ * @app: a #GsApp
+ * @version_history: (element-type AsRelease) (nullable): a set of entries
+ *   representing the version history, or %NULL if none are known
+ *
+ * Set the list of past releases for an application (including the latest one).
+ *
+ * Since: 40
+ **/
+void
+gs_app_set_version_history (GsApp *app, GPtrArray *version_history)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_return_if_fail (GS_IS_APP (app));
+
+	if (version_history != NULL && version_history->len == 0)
+		version_history = NULL;
+
+	locker = g_mutex_locker_new (&priv->mutex);
+	_g_set_ptr_array (&priv->version_history, version_history);
+}
+
+/**
+ * gs_app_ensure_icons_downloaded:
+ * @app: a #GsApp
+ * @soup_session: a #SoupSession
+ * @maximum_icon_size: maximum icon size
+ * @cancellable: (nullable): optional #GCancellable object
+ *
+ * Ensure all remote icons in the @app's icons are locally cached.
+ *
+ * Since: 41
+ **/
+void
+gs_app_ensure_icons_downloaded (GsApp *app,
+				SoupSession *soup_session,
+				guint maximum_icon_size,
+				GCancellable *cancellable)
+{
+	GsAppPrivate *priv;
+	g_autoptr(GMutexLocker) locker = NULL;
+	GPtrArray *icons;
+	guint i;
+
+	g_return_if_fail (GS_IS_APP (app));
+
+	priv = gs_app_get_instance_private (app);
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	/* process all icons */
+	icons = priv->icons;
+
+	for (i = 0; icons != NULL && i < icons->len; i++) {
+		GIcon *icon = g_ptr_array_index (icons, i);
+		g_autoptr(GError) error_local = NULL;
+
+		/* Only remote icons need to be cached. */
+		if (!GS_IS_REMOTE_ICON (icon))
+			continue;
+
+		if (!gs_remote_icon_ensure_cached (GS_REMOTE_ICON (icon),
+						   soup_session,
+						   maximum_icon_size,
+						   cancellable,
+						   &error_local)) {
+			/* we failed, but keep going */
+			g_debug ("failed to cache icon for %s: %s",
+				 gs_app_get_id (app),
+				 error_local->message);
+		}
+	}
+}
+
+/**
+ * gs_app_get_relations:
+ * @app: a #GsApp
+ *
+ * Gets the value of #GsApp:relations. %NULL is equivalent to an empty array.
+ *
+ * The returned array should not be modified.
+ *
+ * Returns: (transfer container) (element-type AsRelation) (nullable): the value of
+ *     #GsApp:relations, or %NULL
+ * Since: 41
+ */
+GPtrArray *
+gs_app_get_relations (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_val_if_fail (GS_IS_APP (app), NULL);
+
+	locker = g_mutex_locker_new (&priv->mutex);
+	return (priv->relations != NULL) ? g_ptr_array_ref (priv->relations) : NULL;
+}
+
+/**
+ * gs_app_add_relation:
+ * @app: a #GsApp
+ * @relation: (transfer none) (not nullable): a new #AsRelation to add to the app
+ *
+ * Adds @relation to #GsApp:relations. @relation must have all its properties
+ * set already.
+ *
+ * Since: 41
+ */
+void
+gs_app_add_relation (GsApp      *app,
+                     AsRelation *relation)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_APP (app));
+	g_return_if_fail (AS_IS_RELATION (relation));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	if (priv->relations == NULL)
+		priv->relations = g_ptr_array_new_with_free_func (g_object_unref);
+	g_ptr_array_add (priv->relations, g_object_ref (relation));
+
+	gs_app_queue_notify (app, obj_props[PROP_RELATIONS]);
+}
+
+/**
+ * gs_app_set_relations:
+ * @app: a #GsApp
+ * @relations: (element-type AsRelation) (nullable) (transfer none): a new set
+ *     of relations for #GsApp:relations; %NULL represents an empty array
+ *
+ * Set #GsApp:relations to @relations, replacing its previous value. %NULL is
+ * equivalent to an empty array.
+ *
+ * Since: 41
+ */
+void
+gs_app_set_relations (GsApp     *app,
+                      GPtrArray *relations)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_autoptr(GPtrArray) old_relations = NULL;
+
+	g_return_if_fail (GS_IS_APP (app));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	if (relations == NULL && priv->relations == NULL)
+		return;
+
+	if (priv->relations != NULL)
+		old_relations = g_steal_pointer (&priv->relations);
+
+	if (relations != NULL)
+		priv->relations = g_ptr_array_ref (relations);
+
+	gs_app_queue_notify (app, obj_props[PROP_RELATIONS]);
+}
+
+/**
+ * gs_app_get_has_translations:
+ * @app: a #GsApp
+ *
+ * Get the value of #GsApp:has-translations.
+ *
+ * Returns: %TRUE if the app has translation metadata, %FALSE otherwise
+ * Since: 41
+ */
+gboolean
+gs_app_get_has_translations (GsApp *app)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+
+	return priv->has_translations;
+}
+
+/**
+ * gs_app_set_has_translations:
+ * @app: a #GsApp
+ * @has_translations: %TRUE if the app has translation metadata, %FALSE otherwise
+ *
+ * Set the value of #GsApp:has-translations.
+ *
+ * Since: 41
+ */
+void
+gs_app_set_has_translations (GsApp    *app,
+                             gboolean  has_translations)
+{
+	GsAppPrivate *priv = gs_app_get_instance_private (app);
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_APP (app));
+
+	locker = g_mutex_locker_new (&priv->mutex);
+
+	if (priv->has_translations == has_translations)
+		return;
+
+	priv->has_translations = has_translations;
+	gs_app_queue_notify (app, obj_props[PROP_HAS_TRANSLATIONS]);
+}
+
+/**
+ * gs_app_is_downloaded:
+ * @app: a #GsApp
+ *
+ * Returns whether the @app is downloaded for updates or not,
+ * considering also its dependencies.
+ *
+ * Returns: %TRUE, when the @app is downloaded, %FALSE otherwise
+ *
+ * Since: 43
+ **/
+gboolean
+gs_app_is_downloaded (GsApp *app)
+{
+	GsSizeType size_type;
+	guint64 size_bytes = 0;
+
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+
+	if (!gs_app_has_quirk (app, GS_APP_QUIRK_IS_PROXY)) {
+		size_type = gs_app_get_size_download (app, &size_bytes);
+		if (size_type != GS_SIZE_TYPE_VALID || size_bytes != 0)
+			return FALSE;
+	}
+
+	size_type = gs_app_get_size_download_dependencies (app, &size_bytes);
+	if (size_type != GS_SIZE_TYPE_VALID || size_bytes != 0)
+		return FALSE;
+
+	return TRUE;
+}
diff --git a/lib/gs-app.h b/lib/gs-app.h
new file mode 100644
index 0000000..5240b2e
--- /dev/null
+++ b/lib/gs-app.h
@@ -0,0 +1,524 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2013-2018 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2014-2018 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib-object.h>
+#include <gdk/gdk.h>
+#include <gdk-pixbuf/gdk-pixbuf.h>
+#include <libsoup/soup.h>
+#include <appstream.h>
+
+#include <gs-app-permissions.h>
+
+G_BEGIN_DECLS
+
+/* Dependency loop means we can’t include the header. */
+typedef struct _GsPlugin GsPlugin;
+typedef struct _GsAppList GsAppList;
+
+#define GS_TYPE_APP (gs_app_get_type ())
+
+G_DECLARE_DERIVABLE_TYPE (GsApp, gs_app, GS, APP, GObject)
+
+struct _GsAppClass
+{
+	GObjectClass		 parent_class;
+	void			 (*to_string)	(GsApp		*app,
+						 GString	*str);
+	gpointer		 padding[30];
+};
+
+/**
+ * GsAppState:
+ * @GS_APP_STATE_UNKNOWN:			Unknown state
+ * @GS_APP_STATE_INSTALLED:			Application is installed
+ * @GS_APP_STATE_AVAILABLE:			Application is available
+ * @GS_APP_STATE_AVAILABLE_LOCAL:		Application is locally available as a file
+ * @GS_APP_STATE_UPDATABLE:			Application is installed and updatable
+ * @GS_APP_STATE_UNAVAILABLE:			Application is referenced, but not available
+ * @GS_APP_STATE_QUEUED_FOR_INSTALL:		Application is queued for install
+ * @GS_APP_STATE_INSTALLING:			Application is being installed
+ * @GS_APP_STATE_REMOVING:			Application is being removed
+ * @GS_APP_STATE_UPDATABLE_LIVE:		Application is installed and updatable live
+ * @GS_APP_STATE_PURCHASABLE:			Application is available for purchasing
+ * @GS_APP_STATE_PURCHASING:			Application is being purchased
+ * @GS_APP_STATE_PENDING_INSTALL:		Application is installed, but may have pending some actions,
+ *						like restart, to finish it
+ * @GS_APP_STATE_PENDING_REMOVE:		Application is removed, but may have pending some actions,
+ *						like restart, to finish it
+ *
+ * The application state.
+ **/
+typedef enum {
+	GS_APP_STATE_UNKNOWN,				/* Since: 0.2.2 */
+	GS_APP_STATE_INSTALLED,				/* Since: 0.2.2 */
+	GS_APP_STATE_AVAILABLE,				/* Since: 0.2.2 */
+	GS_APP_STATE_AVAILABLE_LOCAL,			/* Since: 0.2.2 */
+	GS_APP_STATE_UPDATABLE,				/* Since: 0.2.2 */
+	GS_APP_STATE_UNAVAILABLE,			/* Since: 0.2.2 */
+	GS_APP_STATE_QUEUED_FOR_INSTALL,		/* Since: 0.2.2 */
+	GS_APP_STATE_INSTALLING,			/* Since: 0.2.2 */
+	GS_APP_STATE_REMOVING,				/* Since: 0.2.2 */
+	GS_APP_STATE_UPDATABLE_LIVE,			/* Since: 0.5.4 */
+	GS_APP_STATE_PURCHASABLE,			/* Since: 0.5.17 */
+	GS_APP_STATE_PURCHASING,			/* Since: 0.5.17 */
+	GS_APP_STATE_PENDING_INSTALL,			/* Since: 41 */
+	GS_APP_STATE_PENDING_REMOVE,			/* Since: 41 */
+	GS_APP_STATE_LAST  /*< skip >*/
+} GsAppState;
+
+/**
+ * GsAppSpecialKind:
+ * @GS_APP_SPECIAL_KIND_NONE:			No special occupation
+ * @GS_APP_SPECIAL_KIND_OS_UPDATE:		Application represents an OS update
+ *
+ * A special occupation for #GsApp. #AsComponentKind can not represent certain
+ * GNOME Software specific features, like representing a #GsApp as OS updates
+ * which have no associated AppStream entry.
+ * They are represented by a #GsApp of kind %AS_COMPONENT_KIND_GENERIC and a value
+ * from #GsAppSpecialKind. which does not match any AppStream component type.
+ **/
+typedef enum {
+	GS_APP_SPECIAL_KIND_NONE,		/* Since: 40 */
+	GS_APP_SPECIAL_KIND_OS_UPDATE,		/* Since: 40 */
+} GsAppSpecialKind;
+
+/**
+ * GsAppKudo:
+ * @GS_APP_KUDO_MY_LANGUAGE:		Localised in my language
+ * @GS_APP_KUDO_RECENT_RELEASE:		Released recently
+ * @GS_APP_KUDO_FEATURED_RECOMMENDED:	Chosen for the front page
+ * @GS_APP_KUDO_MODERN_TOOLKIT:		Uses a modern toolkit
+ * @GS_APP_KUDO_SEARCH_PROVIDER:	Provides a search provider
+ * @GS_APP_KUDO_INSTALLS_USER_DOCS:	Installs user docs
+ * @GS_APP_KUDO_USES_NOTIFICATIONS:	Registers notifications
+ * @GS_APP_KUDO_HAS_KEYWORDS:		Has at least 1 keyword
+ * @GS_APP_KUDO_HAS_SCREENSHOTS:	Supplies screenshots
+ * @GS_APP_KUDO_HIGH_CONTRAST:		Installs a high contrast icon
+ * @GS_APP_KUDO_HI_DPI_ICON:		Installs a HiDPI icon
+ * @GS_APP_KUDO_SANDBOXED:		Application is sandboxed
+ * @GS_APP_KUDO_SANDBOXED_SECURE:	Application is sandboxed securely
+ *
+ * Any awards given to the application.
+ **/
+typedef enum {
+	GS_APP_KUDO_MY_LANGUAGE			= 1 << 0,
+	GS_APP_KUDO_RECENT_RELEASE		= 1 << 1,
+	GS_APP_KUDO_FEATURED_RECOMMENDED	= 1 << 2,
+	GS_APP_KUDO_MODERN_TOOLKIT		= 1 << 3,
+	GS_APP_KUDO_SEARCH_PROVIDER		= 1 << 4,
+	GS_APP_KUDO_INSTALLS_USER_DOCS		= 1 << 5,
+	GS_APP_KUDO_USES_NOTIFICATIONS		= 1 << 6,
+	GS_APP_KUDO_HAS_KEYWORDS		= 1 << 7,
+	GS_APP_KUDO_HAS_SCREENSHOTS		= 1 << 9,
+	GS_APP_KUDO_HIGH_CONTRAST		= 1 << 13,
+	GS_APP_KUDO_HI_DPI_ICON			= 1 << 14,
+	GS_APP_KUDO_SANDBOXED			= 1 << 15,
+	GS_APP_KUDO_SANDBOXED_SECURE		= 1 << 16,
+	GS_APP_KUDO_LAST  /*< skip >*/
+} GsAppKudo;
+
+/**
+ * GsAppQuirk:
+ * @GS_APP_QUIRK_NONE:			No special attributes
+ * @GS_APP_QUIRK_PROVENANCE:		Installed by OS vendor
+ * @GS_APP_QUIRK_COMPULSORY:		Cannot be removed
+ * @GS_APP_QUIRK_HAS_SOURCE:		Has a source to allow staying up-to-date
+ * @GS_APP_QUIRK_IS_WILDCARD:		Matches applications from any plugin
+ * @GS_APP_QUIRK_NEEDS_REBOOT:		A reboot is required after the action
+ * @GS_APP_QUIRK_NOT_REVIEWABLE:	The app is not reviewable
+ * @GS_APP_QUIRK_NOT_LAUNCHABLE:	The app is not launchable (run-able)
+ * @GS_APP_QUIRK_NEEDS_USER_ACTION:	The component requires some kind of user action
+ * @GS_APP_QUIRK_IS_PROXY:		Is a proxy app that operates on other applications
+ * @GS_APP_QUIRK_REMOVABLE_HARDWARE:	The device is unusable whilst the action is performed
+ * @GS_APP_QUIRK_DEVELOPER_VERIFIED:	The app developer has been verified
+ * @GS_APP_QUIRK_PARENTAL_FILTER:	The app has been filtered by parental controls, and should be hidden
+ * @GS_APP_QUIRK_NEW_PERMISSIONS:	The update requires new permissions
+ * @GS_APP_QUIRK_PARENTAL_NOT_LAUNCHABLE:	The app cannot be run by the current user due to parental controls, and should not be launchable
+ * @GS_APP_QUIRK_HIDE_FROM_SEARCH:	The app should not be shown in search results
+ * @GS_APP_QUIRK_HIDE_EVERYWHERE:	The app should not be shown anywhere (it’s blocklisted)
+ * @GS_APP_QUIRK_DO_NOT_AUTO_UPDATE:	The app should not be automatically updated
+ * @GS_APP_QUIRK_DEVELOPMENT_SOURCE:	The app is from a development source (Since: 43)
+ *
+ * The application attributes.
+ **/
+typedef enum {
+	GS_APP_QUIRK_NONE		= 0,		/* Since: 3.32 */
+	GS_APP_QUIRK_PROVENANCE		= 1 << 0,	/* Since: 3.32 */
+	GS_APP_QUIRK_COMPULSORY		= 1 << 1,	/* Since: 3.32 */
+	GS_APP_QUIRK_HAS_SOURCE		= 1 << 2,	/* Since: 3.32 */
+	GS_APP_QUIRK_IS_WILDCARD	= 1 << 3,	/* Since: 3.32 */
+	GS_APP_QUIRK_NEEDS_REBOOT	= 1 << 4,	/* Since: 3.32 */
+	GS_APP_QUIRK_NOT_REVIEWABLE	= 1 << 5,	/* Since: 3.32 */
+	/* there’s a hole here where GS_APP_QUIRK_HAS_SHORTCUT used to be */
+	GS_APP_QUIRK_NOT_LAUNCHABLE	= 1 << 7,	/* Since: 3.32 */
+	GS_APP_QUIRK_NEEDS_USER_ACTION	= 1 << 8,	/* Since: 3.32 */
+	GS_APP_QUIRK_IS_PROXY 		= 1 << 9,	/* Since: 3.32 */
+	GS_APP_QUIRK_REMOVABLE_HARDWARE	= 1 << 10,	/* Since: 3.32 */
+	GS_APP_QUIRK_DEVELOPER_VERIFIED	= 1 << 11,	/* Since: 3.32 */
+	GS_APP_QUIRK_PARENTAL_FILTER	= 1 << 12,	/* Since: 3.32 */
+	GS_APP_QUIRK_NEW_PERMISSIONS	= 1 << 13,	/* Since: 3.32 */
+	GS_APP_QUIRK_PARENTAL_NOT_LAUNCHABLE	= 1 << 14,	/* Since: 3.32 */
+	GS_APP_QUIRK_HIDE_FROM_SEARCH	= 1 << 15,	/* Since: 3.32 */
+	GS_APP_QUIRK_HIDE_EVERYWHERE	= 1 << 16,	/* Since: 3.36 */
+	GS_APP_QUIRK_DO_NOT_AUTO_UPDATE	= 1 << 17,	/* Since: 3.36 */
+	GS_APP_QUIRK_DEVELOPMENT_SOURCE	= 1 << 18,	/* Since: 43 */
+	GS_APP_QUIRK_LAST  /*< skip >*/
+} GsAppQuirk;
+
+#define	GS_APP_INSTALL_DATE_UNSET		0
+#define	GS_APP_INSTALL_DATE_UNKNOWN		1 /* 1s past the epoch */
+
+/**
+ * GsSizeType:
+ * @GS_SIZE_TYPE_UNKNOWN:	Size is unknown
+ * @GS_SIZE_TYPE_UNKNOWABLE:	Size is unknown and is impossible to calculate
+ * @GS_SIZE_TYPE_VALID:		Size is known and valid
+ *
+ * Types of download or file size for applications.
+ *
+ * These are used to represent the validity of properties like
+ * #GsApp:size-download.
+ *
+ * Since: 43
+ */
+typedef enum {
+	GS_SIZE_TYPE_UNKNOWN,
+	GS_SIZE_TYPE_UNKNOWABLE,
+	GS_SIZE_TYPE_VALID,
+} GsSizeType;
+
+/**
+ * GsAppQuality:
+ * @GS_APP_QUALITY_UNKNOWN:	The quality value is unknown
+ * @GS_APP_QUALITY_LOWEST:	Lowest quality
+ * @GS_APP_QUALITY_NORMAL:	Normal quality
+ * @GS_APP_QUALITY_HIGHEST:	Highest quality
+ *
+ * Any awards given to the application.
+ **/
+typedef enum {
+	GS_APP_QUALITY_UNKNOWN,
+	GS_APP_QUALITY_LOWEST,
+	GS_APP_QUALITY_NORMAL,
+	GS_APP_QUALITY_HIGHEST,
+	GS_APP_QUALITY_LAST  /*< skip >*/
+} GsAppQuality;
+
+/**
+ * GS_APP_PROGRESS_UNKNOWN:
+ *
+ * A value returned by gs_app_get_progress() if the app’s progress is unknown
+ * or has a wide confidence interval. Typically this would be represented in the
+ * UI using a pulsing progress bar or spinner.
+ *
+ * Since: 3.38
+ */
+#define GS_APP_PROGRESS_UNKNOWN G_MAXUINT
+
+const gchar 	*gs_app_state_to_string (GsAppState state);
+
+GsApp		*gs_app_new			(const gchar	*id);
+G_DEPRECATED_FOR(gs_app_set_from_unique_id)
+GsApp		*gs_app_new_from_unique_id	(const gchar	*unique_id);
+void		 gs_app_set_from_unique_id	(GsApp		*app,
+						 const gchar	*unique_id,
+						 AsComponentKind kind);
+gchar		*gs_app_to_string		(GsApp		*app);
+void		 gs_app_to_string_append	(GsApp		*app,
+						 GString	*str);
+
+const gchar	*gs_app_get_id			(GsApp		*app);
+void		 gs_app_set_id			(GsApp		*app,
+						 const gchar	*id);
+AsComponentKind	 gs_app_get_kind		(GsApp		*app);
+void		 gs_app_set_kind		(GsApp		*app,
+						 AsComponentKind kind);
+GsAppState	 gs_app_get_state		(GsApp		*app);
+void		 gs_app_set_state		(GsApp		*app,
+						 GsAppState	 state);
+AsComponentScope gs_app_get_scope		(GsApp		*app);
+void		 gs_app_set_scope		(GsApp		*app,
+						 AsComponentScope scope);
+AsBundleKind	 gs_app_get_bundle_kind		(GsApp		*app);
+void		 gs_app_set_bundle_kind		(GsApp		*app,
+						 AsBundleKind	 bundle_kind);
+GsAppSpecialKind gs_app_get_special_kind	(GsApp		*app);
+void		 gs_app_set_special_kind	(GsApp		*app,
+						 GsAppSpecialKind kind);
+void		 gs_app_set_state_recover	(GsApp		*app);
+guint		 gs_app_get_progress		(GsApp		*app);
+void		 gs_app_set_progress		(GsApp		*app,
+						 guint		 percentage);
+gboolean	gs_app_get_allow_cancel		(GsApp	*app);
+void		gs_app_set_allow_cancel		 (GsApp	*app,
+						  gboolean	allow_cancel);
+const gchar	*gs_app_get_unique_id		(GsApp		*app);
+const gchar	*gs_app_get_branch		(GsApp		*app);
+void		 gs_app_set_branch		(GsApp		*app,
+						 const gchar	*branch);
+const gchar	*gs_app_get_name		(GsApp		*app);
+void		 gs_app_set_name		(GsApp		*app,
+						 GsAppQuality	 quality,
+						 const gchar	*name);
+const gchar	*gs_app_get_renamed_from	(GsApp		*app);
+void		 gs_app_set_renamed_from	(GsApp		*app,
+						 const gchar	*renamed_from);
+const gchar	*gs_app_get_source_default	(GsApp		*app);
+void		 gs_app_add_source		(GsApp		*app,
+						 const gchar	*source);
+GPtrArray	*gs_app_get_sources		(GsApp		*app);
+void		 gs_app_set_sources		(GsApp		*app,
+						 GPtrArray	*sources);
+const gchar	*gs_app_get_source_id_default	(GsApp		*app);
+void		 gs_app_add_source_id		(GsApp		*app,
+						 const gchar	*source_id);
+GPtrArray	*gs_app_get_source_ids		(GsApp		*app);
+void		 gs_app_set_source_ids		(GsApp		*app,
+						 GPtrArray	*source_ids);
+void		 gs_app_clear_source_ids	(GsApp		*app);
+const gchar	*gs_app_get_project_group	(GsApp		*app);
+void		 gs_app_set_project_group	(GsApp		*app,
+						 const gchar	*project_group);
+const gchar	*gs_app_get_developer_name	(GsApp		*app);
+void		 gs_app_set_developer_name	(GsApp		*app,
+						 const gchar	*developer_name);
+const gchar	*gs_app_get_agreement		(GsApp		*app);
+void		 gs_app_set_agreement		(GsApp		*app,
+						 const gchar	*agreement);
+const gchar	*gs_app_get_version		(GsApp		*app);
+const gchar	*gs_app_get_version_ui		(GsApp		*app);
+void		 gs_app_set_version		(GsApp		*app,
+						 const gchar	*version);
+const gchar	*gs_app_get_summary		(GsApp		*app);
+void		 gs_app_set_summary		(GsApp		*app,
+						 GsAppQuality	 quality,
+						 const gchar	*summary);
+const gchar	*gs_app_get_summary_missing	(GsApp		*app);
+void		 gs_app_set_summary_missing	(GsApp		*app,
+						 const gchar	*summary_missing);
+const gchar	*gs_app_get_description		(GsApp		*app);
+void		 gs_app_set_description		(GsApp		*app,
+						 GsAppQuality	 quality,
+						 const gchar	*description);
+const gchar	*gs_app_get_url			(GsApp		*app,
+						 AsUrlKind	 kind);
+void		 gs_app_set_url			(GsApp		*app,
+						 AsUrlKind	 kind,
+						 const gchar	*url);
+const gchar	*gs_app_get_url_missing		(GsApp		*app);
+void		 gs_app_set_url_missing		(GsApp		*app,
+						 const gchar	*url);
+const gchar	*gs_app_get_launchable		(GsApp		*app,
+						 AsLaunchableKind kind);
+void		 gs_app_set_launchable		(GsApp		*app,
+						 AsLaunchableKind kind,
+						 const gchar	*launchable);
+const gchar	*gs_app_get_license		(GsApp		*app);
+gboolean	 gs_app_get_license_is_free	(GsApp		*app);
+void		 gs_app_set_license		(GsApp		*app,
+						 GsAppQuality	 quality,
+						 const gchar	*license);
+gchar		**gs_app_get_menu_path		(GsApp		*app);
+void		 gs_app_set_menu_path		(GsApp		*app,
+						 gchar		**menu_path);
+const gchar	*gs_app_get_origin		(GsApp		*app);
+void		 gs_app_set_origin		(GsApp		*app,
+						 const gchar	*origin);
+const gchar	*gs_app_get_origin_appstream	(GsApp		*app);
+void		 gs_app_set_origin_appstream	(GsApp		*app,
+						 const gchar	*origin_appstream);
+const gchar	*gs_app_get_origin_hostname	(GsApp		*app);
+void		 gs_app_set_origin_hostname	(GsApp		*app,
+						 const gchar	*origin_hostname);
+GPtrArray	*gs_app_get_screenshots		(GsApp		*app);
+void		 gs_app_add_screenshot		(GsApp		*app,
+						 AsScreenshot	*screenshot);
+AsScreenshot	*gs_app_get_action_screenshot	(GsApp		*app);
+void		 gs_app_set_action_screenshot	(GsApp		*app,
+						 AsScreenshot	*screenshot);
+const gchar	*gs_app_get_update_version	(GsApp		*app);
+const gchar	*gs_app_get_update_version_ui	(GsApp		*app);
+void		 gs_app_set_update_version	(GsApp		*app,
+						 const gchar	*update_version);
+const gchar	*gs_app_get_update_details_markup
+						(GsApp		*app);
+void		 gs_app_set_update_details_markup
+						(GsApp		*app,
+						 const gchar	*markup);
+void		 gs_app_set_update_details_text	(GsApp		*app,
+						 const gchar	*text);
+AsUrgencyKind	 gs_app_get_update_urgency	(GsApp		*app);
+void		 gs_app_set_update_urgency	(GsApp		*app,
+						 AsUrgencyKind	 update_urgency);
+GsPlugin	*gs_app_dup_management_plugin	(GsApp		*app);
+gboolean	 gs_app_has_management_plugin	(GsApp		*app,
+						 GsPlugin	*plugin);
+void		 gs_app_set_management_plugin	(GsApp		*app,
+						 GsPlugin	*management_plugin);
+GIcon		*gs_app_get_icon_for_size	(GsApp		*app,
+						 guint		 size,
+						 guint		 scale,
+						 const gchar	*fallback_icon_name);
+GPtrArray	*gs_app_get_icons		(GsApp		*app);
+void		 gs_app_add_icon		(GsApp		*app,
+						 GIcon		*icon);
+void		 gs_app_remove_all_icons	(GsApp		*app);
+GFile		*gs_app_get_local_file		(GsApp		*app);
+void		 gs_app_set_local_file		(GsApp		*app,
+						 GFile		*local_file);
+AsContentRating	*gs_app_dup_content_rating	(GsApp		*app);
+void		 gs_app_set_content_rating	(GsApp		*app,
+						 AsContentRating *content_rating);
+GsApp		*gs_app_get_runtime		(GsApp		*app);
+void		 gs_app_set_runtime		(GsApp		*app,
+						 GsApp		*runtime);
+const gchar	*gs_app_get_metadata_item	(GsApp		*app,
+						 const gchar	*key);
+GVariant	*gs_app_get_metadata_variant	(GsApp		*app,
+						 const gchar	*key);
+void		 gs_app_set_metadata		(GsApp		*app,
+						 const gchar	*key,
+						 const gchar	*value);
+void		 gs_app_set_metadata_variant	(GsApp		*app,
+						 const gchar	*key,
+						 GVariant	*value);
+gint		 gs_app_get_rating		(GsApp		*app);
+void		 gs_app_set_rating		(GsApp		*app,
+						 gint		 rating);
+GArray		*gs_app_get_review_ratings	(GsApp		*app);
+void		 gs_app_set_review_ratings	(GsApp		*app,
+						 GArray		*review_ratings);
+GPtrArray	*gs_app_get_reviews		(GsApp		*app);
+void		 gs_app_add_review		(GsApp		*app,
+						 AsReview	*review);
+void		 gs_app_remove_review		(GsApp		*app,
+						 AsReview	*review);
+GPtrArray	*gs_app_get_provided		(GsApp		*app);
+AsProvided	*gs_app_get_provided_for_kind	(GsApp		*app,
+						 AsProvidedKind kind);
+void		 gs_app_add_provided_item	(GsApp		*app,
+						 AsProvidedKind kind,
+						 const gchar	*item);
+GsSizeType	 gs_app_get_size_installed	(GsApp		*app,
+						 guint64	*size_bytes_out);
+void		 gs_app_set_size_installed	(GsApp		*app,
+						 GsSizeType	 size_type,
+						 guint64	 size_bytes);
+GsSizeType	 gs_app_get_size_installed_dependencies
+						(GsApp		*app,
+						 guint64	*size_bytes_out);
+GsSizeType	 gs_app_get_size_user_data	(GsApp		*app,
+						 guint64	*size_bytes_out);
+void		 gs_app_set_size_user_data	(GsApp		*app,
+						 GsSizeType	 size_type,
+						 guint64	 size_bytes);
+GsSizeType	 gs_app_get_size_cache_data	(GsApp		*app,
+						 guint64	*size_bytes_out);
+void		 gs_app_set_size_cache_data	(GsApp		*app,
+						 GsSizeType	 size_type,
+						 guint64	 size_bytes);
+GsSizeType	 gs_app_get_size_download	(GsApp		*app,
+						 guint64	*size_bytes_out);
+void		 gs_app_set_size_download	(GsApp		*app,
+						 GsSizeType	 size_type,
+						 guint64	 size_bytes);
+GsSizeType	 gs_app_get_size_download_dependencies
+						(GsApp		*app,
+						 guint64	*size_bytes_out);
+void		 gs_app_add_related		(GsApp		*app,
+						 GsApp		*app2);
+void		 gs_app_add_addons		(GsApp		*app,
+						 GsAppList	*addons);
+void		 gs_app_add_history		(GsApp		*app,
+						 GsApp		*app2);
+guint64		 gs_app_get_install_date	(GsApp		*app);
+void		 gs_app_set_install_date	(GsApp		*app,
+						 guint64	 install_date);
+guint64		 gs_app_get_release_date	(GsApp		*app);
+void		 gs_app_set_release_date	(GsApp		*app,
+						 guint64	 release_date);
+GPtrArray	*gs_app_get_categories		(GsApp		*app);
+void		 gs_app_set_categories		(GsApp		*app,
+						 GPtrArray	*categories);
+GArray		*gs_app_get_key_colors		(GsApp		*app);
+void		 gs_app_set_key_colors		(GsApp		*app,
+						 GArray		*key_colors);
+void		 gs_app_add_key_color		(GsApp		*app,
+						 GdkRGBA	*key_color);
+gboolean	gs_app_get_user_key_colors	(GsApp		*app);
+void            gs_app_set_is_update_downloaded (GsApp         *app,
+                                                 gboolean       is_update_downloaded);
+gboolean        gs_app_get_is_update_downloaded (GsApp         *app);
+gboolean	 gs_app_has_category		(GsApp		*app,
+						 const gchar	*category);
+void		 gs_app_add_category		(GsApp		*app,
+						 const gchar	*category);
+gboolean	 gs_app_remove_category		(GsApp		*app,
+						 const gchar	*category);
+void		 gs_app_add_kudo		(GsApp		*app,
+						 GsAppKudo	 kudo);
+void		 gs_app_remove_kudo		(GsApp		*app,
+						 GsAppKudo	 kudo);
+gboolean	 gs_app_has_kudo		(GsApp		*app,
+						 GsAppKudo	 kudo);
+guint64		 gs_app_get_kudos		(GsApp		*app);
+guint		 gs_app_get_kudos_percentage	(GsApp		*app);
+gboolean	 gs_app_get_to_be_installed	(GsApp		*app);
+void		 gs_app_set_to_be_installed	(GsApp		*app,
+						 gboolean	 to_be_installed);
+void		 gs_app_set_match_value		(GsApp		*app,
+						 guint		 match_value);
+guint		 gs_app_get_match_value		(GsApp		*app);
+
+gboolean	 gs_app_has_quirk		(GsApp		*app,
+						 GsAppQuirk	 quirk);
+void		 gs_app_add_quirk		(GsApp		*app,
+						 GsAppQuirk	 quirk);
+void		 gs_app_remove_quirk		(GsApp		*app,
+						 GsAppQuirk	 quirk);
+gboolean	 gs_app_is_installed		(GsApp		*app);
+gboolean	 gs_app_is_updatable		(GsApp		*app);
+gchar		*gs_app_dup_origin_ui		(GsApp		*app,
+						 gboolean	 with_packaging_format);
+void		 gs_app_set_origin_ui		(GsApp		*app,
+						 const gchar	*origin_ui);
+gchar		*gs_app_get_packaging_format	(GsApp		*app);
+const gchar	*gs_app_get_packaging_format_raw(GsApp *app);
+void		 gs_app_subsume_metadata	(GsApp		*app,
+						 GsApp		*donor);
+GsAppPermissions *
+		 gs_app_dup_permissions		(GsApp		*app);
+void		 gs_app_set_permissions		(GsApp		*app,
+						 GsAppPermissions *permissions);
+GsAppPermissions *
+		 gs_app_dup_update_permissions	(GsApp		*app);
+void		 gs_app_set_update_permissions	(GsApp		*app,
+						 GsAppPermissions *update_permissions);
+GPtrArray	*gs_app_get_version_history	(GsApp		*app);
+void		 gs_app_set_version_history	(GsApp		*app,
+						 GPtrArray	*version_history);
+void		gs_app_ensure_icons_downloaded	(GsApp		*app,
+						 SoupSession	*soup_session,
+						 guint		 maximum_icon_size,
+						 GCancellable	*cancellable);
+
+GPtrArray	*gs_app_get_relations		(GsApp		*app);
+void		 gs_app_add_relation		(GsApp		*app,
+						 AsRelation	*relation);
+void		 gs_app_set_relations		(GsApp		*app,
+						 GPtrArray	*relations);
+
+gboolean	 gs_app_get_has_translations	(GsApp		*app);
+void		 gs_app_set_has_translations	(GsApp		*app,
+						 gboolean	 has_translations);
+gboolean	 gs_app_is_downloaded		(GsApp		*app);
+
+G_END_DECLS
diff --git a/lib/gs-appstream.c b/lib/gs-appstream.c
new file mode 100644
index 0000000..fa94a6e
--- /dev/null
+++ b/lib/gs-appstream.c
@@ -0,0 +1,2165 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2015-2017 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2018-2019 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include "config.h"
+
+#include <gnome-software.h>
+#include <locale.h>
+
+#include "gs-appstream.h"
+
+#define	GS_APPSTREAM_MAX_SCREENSHOTS	5
+
+GsApp *
+gs_appstream_create_app (GsPlugin *plugin, XbSilo *silo, XbNode *component, GError **error)
+{
+	GsApp *app;
+	g_autoptr(GsApp) app_new = NULL;
+
+	/* The 'plugin' can be NULL, when creating app for --show-metainfo */
+	g_return_val_if_fail (XB_IS_SILO (silo), NULL);
+	g_return_val_if_fail (XB_IS_NODE (component), NULL);
+
+	app_new = gs_app_new (NULL);
+
+	/* refine enough to get the unique ID */
+	if (!gs_appstream_refine_app (plugin, app_new, silo, component,
+				      GS_PLUGIN_REFINE_FLAGS_REQUIRE_ID,
+				      error))
+		return NULL;
+
+	/* never add wildcard apps to the plugin cache, and only add to
+	 * the cache if it’s available */
+	if (gs_app_has_quirk (app_new, GS_APP_QUIRK_IS_WILDCARD) || plugin == NULL)
+		return g_steal_pointer (&app_new);
+
+	if (plugin == NULL)
+		return g_steal_pointer (&app_new);
+
+	/* look for existing object */
+	app = gs_plugin_cache_lookup (plugin, gs_app_get_unique_id (app_new));
+	if (app != NULL)
+		return app;
+
+	/* use the temp object we just created */
+	gs_app_set_metadata (app_new, "GnomeSoftware::Creator",
+			     gs_plugin_get_name (plugin));
+	gs_plugin_cache_add (plugin, NULL, app_new);
+	return g_steal_pointer (&app_new);
+}
+
+/* Helper function to do the equivalent of
+ *  *node = xb_node_get_next (*node)
+ * but with correct reference counting, since xb_node_get_next() returns a new
+ * ref. */
+static void
+node_set_to_next (XbNode **node)
+{
+	g_autoptr(XbNode) next_node = NULL;
+
+	g_assert (node != NULL);
+	g_assert (*node != NULL);
+
+	next_node = xb_node_get_next (*node);
+	g_object_unref (*node);
+	*node = g_steal_pointer (&next_node);
+}
+
+/* Returns escaped text */
+static gchar *
+gs_appstream_format_description_text (XbNode *node)
+{
+	g_autoptr(GString) str = g_string_new (NULL);
+	const gchar *node_text;
+
+	if (node == NULL)
+		return NULL;
+
+	node_text = xb_node_get_text (node);
+	if (node_text != NULL && *node_text != '\0') {
+		g_autofree gchar *escaped = g_markup_escape_text (node_text, -1);
+		g_string_append (str, escaped);
+	}
+
+	for (g_autoptr(XbNode) n = xb_node_get_child (node); n != NULL; node_set_to_next (&n)) {
+		const gchar *start_elem = "", *end_elem = "";
+		g_autofree gchar *text = NULL;
+		if (g_strcmp0 (xb_node_get_element (n), "em") == 0) {
+			start_elem = "<i>";
+			end_elem = "</i>";
+		} else if (g_strcmp0 (xb_node_get_element (n), "code") == 0) {
+			start_elem = "<tt>";
+			end_elem = "</tt>";
+		}
+
+		/* These can be nested */
+		text = gs_appstream_format_description_text (n);
+		if (text != NULL) {
+			g_string_append_printf (str, "%s%s%s", start_elem, text, end_elem);
+		}
+
+		node_text = xb_node_get_tail (n);
+		if (node_text != NULL && *node_text != '\0') {
+			g_autofree gchar *escaped = g_markup_escape_text (node_text, -1);
+			g_string_append (str, escaped);
+		}
+	}
+
+	if (str->len == 0)
+		return NULL;
+
+	return g_string_free (g_steal_pointer (&str), FALSE);
+}
+
+static gchar *
+gs_appstream_format_description (XbNode *root, GError **error)
+{
+	g_autoptr(GString) str = g_string_new (NULL);
+
+	for (g_autoptr(XbNode) n = xb_node_get_child (root); n != NULL; node_set_to_next (&n)) {
+		/* support <p>, <em>, <code>, <ul>, <ol> and <li>, ignore all else */
+		if (g_strcmp0 (xb_node_get_element (n), "p") == 0) {
+			g_autofree gchar *escaped = gs_appstream_format_description_text (n);
+			/* Treat a self-closing paragraph (`<p/>`) as
+			 * nonexistent. This is consistent with Firefox. */
+			if (escaped != NULL)
+				g_string_append_printf (str, "%s\n\n", escaped);
+		} else if (g_strcmp0 (xb_node_get_element (n), "ul") == 0) {
+			g_autoptr(GPtrArray) children = xb_node_get_children (n);
+
+			for (guint i = 0; i < children->len; i++) {
+				XbNode *nc = g_ptr_array_index (children, i);
+				if (g_strcmp0 (xb_node_get_element (nc), "li") == 0) {
+					g_autofree gchar *escaped = gs_appstream_format_description_text (nc);
+
+					/* Treat a self-closing `<li/>` as an empty
+					 * list element (equivalent to `<li></li>`).
+					 * This is consistent with Firefox. */
+					g_string_append_printf (str, " • %s\n",
+								(escaped != NULL) ? escaped : "");
+				}
+			}
+			g_string_append (str, "\n");
+		} else if (g_strcmp0 (xb_node_get_element (n), "ol") == 0) {
+			g_autoptr(GPtrArray) children = xb_node_get_children (n);
+			for (guint i = 0; i < children->len; i++) {
+				XbNode *nc = g_ptr_array_index (children, i);
+				if (g_strcmp0 (xb_node_get_element (nc), "li") == 0) {
+					g_autofree gchar *escaped = gs_appstream_format_description_text (nc);
+
+					/* Treat self-closing elements as with `<ul>` above. */
+					g_string_append_printf (str, " %u. %s\n",
+								i + 1,
+								(escaped != NULL) ? escaped : "");
+				}
+			}
+			g_string_append (str, "\n");
+		}
+	}
+
+	/* remove extra newlines */
+	while (str->len > 0 && str->str[str->len - 1] == '\n')
+		g_string_truncate (str, str->len - 1);
+
+	/* success */
+	return g_string_free (g_steal_pointer (&str), FALSE);
+}
+
+static gchar *
+gs_appstream_build_icon_prefix (XbNode *component)
+{
+	const gchar *origin;
+	const gchar *tmp;
+	gint npath;
+	g_auto(GStrv) path = NULL;
+	g_autoptr(XbNode) components = NULL;
+
+	/* no parent, e.g. AppData */
+	components = xb_node_get_parent (component);
+	if (components == NULL)
+		return NULL;
+
+	/* set explicitly */
+	tmp = xb_node_query_text (components, "info/icon-prefix", NULL);
+	if (tmp != NULL)
+		return g_strdup (tmp);
+
+	/* fall back to origin */
+	origin = xb_node_get_attr (components, "origin");
+	if (origin == NULL)
+		return NULL;
+
+	/* no metadata */
+	tmp = xb_node_query_text (components, "info/filename", NULL);
+	if (tmp == NULL)
+		return NULL;
+
+	/* check format */
+	path = g_strsplit (tmp, "/", -1);
+	npath = g_strv_length (path);
+	if (npath < 3 ||
+	    !(g_strcmp0 (path[npath-2], "xmls") == 0 ||
+	      g_strcmp0 (path[npath-2], "yaml") == 0 ||
+	      g_strcmp0 (path[npath-2], "xml") == 0))
+		return NULL;
+
+	/* fix the new path */
+	g_free (path[npath-1]);
+	g_free (path[npath-2]);
+	path[npath-1] = g_strdup (origin);
+	path[npath-2] = g_strdup ("icons");
+	return g_strjoinv ("/", path);
+}
+
+/* This function is designed to do no disk or network I/O. */
+static AsIcon *
+gs_appstream_new_icon (XbNode *component, XbNode *n, AsIconKind icon_kind, guint sz)
+{
+	AsIcon *icon = as_icon_new ();
+	g_autofree gchar *icon_path = NULL;
+	as_icon_set_kind (icon, icon_kind);
+	switch (icon_kind) {
+	case AS_ICON_KIND_LOCAL:
+		as_icon_set_filename (icon, xb_node_get_text (n));
+		break;
+	case AS_ICON_KIND_REMOTE:
+		as_icon_set_url (icon, xb_node_get_text (n));
+		break;
+	default:
+		as_icon_set_name (icon, xb_node_get_text (n));
+	}
+	if (sz == 0) {
+		guint64 width = xb_node_get_attr_as_uint (n, "width");
+		if (width > 0 && width < G_MAXUINT)
+			sz = width;
+	}
+
+	if (sz > 0) {
+		as_icon_set_width (icon, sz);
+		as_icon_set_height (icon, sz);
+	}
+
+	if (icon_kind != AS_ICON_KIND_LOCAL && icon_kind != AS_ICON_KIND_REMOTE) {
+		/* add partial filename for now, we will compose the full one later */
+		icon_path = gs_appstream_build_icon_prefix (component);
+		as_icon_set_filename (icon, icon_path);
+	}
+	return icon;
+}
+
+static void
+app_add_icon (GsApp  *app,
+              AsIcon *as_icon)
+{
+	g_autoptr(GIcon) icon = gs_icon_new_for_appstream_icon (as_icon);
+	if (icon != NULL)
+		gs_app_add_icon (app, icon);
+}
+
+static void
+traverse_component_icons (GsApp *app,
+			  XbNode *component,
+			  GPtrArray *icons)
+{
+	if (!icons)
+		return;
+
+	/* This code deliberately does *not* check that the icon files or theme
+	 * icons exist, as that would mean doing disk I/O for all the apps in
+	 * the appstream file, regardless of whether the calling code is
+	 * actually going to use the icons. Better to add all the possible icons
+	 * and let the calling code check which ones exist, if it needs to. */
+	for (guint i = 0; i < icons->len; i++) {
+		XbNode *icon_node = g_ptr_array_index (icons, i);
+		g_autoptr(AsIcon) icon = NULL;
+		const gchar *icon_kind_str = xb_node_get_attr (icon_node, "type");
+		AsIconKind icon_kind = as_icon_kind_from_string (icon_kind_str);
+
+		if (icon_kind == AS_ICON_KIND_UNKNOWN) {
+			g_debug ("unknown icon kind ‘%s’", icon_kind_str);
+			continue;
+		}
+
+		icon = gs_appstream_new_icon (component, icon_node, icon_kind, 0);
+		app_add_icon (app, icon);
+	}
+}
+
+static void
+traverse_components_xpath_for_icons (GsApp *app,
+				     XbSilo *silo,
+				     const gchar *xpath,
+				     gboolean try_with_launchable)
+{
+	g_autoptr(GPtrArray) components = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	components = xb_silo_query (silo, xpath, 0, &local_error);
+	if (components) {
+		for (guint i = 0; i < components->len; i++) {
+			g_autoptr(GPtrArray) icons = NULL;  /* (element-type XbNode) */
+			XbNode *component = g_ptr_array_index (components, i);
+			g_autofree gchar *xml = xb_node_export (component, 0, NULL);
+			icons = xb_node_query (component, "icon", 0, NULL);
+			traverse_component_icons (app, component, icons);
+
+			if (try_with_launchable && gs_app_get_icons (app) == NULL) {
+				const gchar *launchable_id = xb_node_query_text (component, "launchable[@type='desktop-id']", NULL);
+				if (launchable_id != NULL) {
+					g_autofree gchar *xpath2 = NULL;
+
+					/* Inherit the icon from the .desktop file */
+					xpath2 = g_strdup_printf ("/component[@type='desktop-application']/launchable[@type='desktop-id'][text()='%s']/..",
+								  launchable_id);
+					traverse_components_xpath_for_icons (app, silo, xpath2, FALSE);
+				}
+			}
+		}
+	}
+}
+
+static void
+gs_appstream_refine_icon (GsApp *app,
+			  XbSilo *silo,
+			  XbNode *component)
+{
+	g_autoptr(GError) local_error = NULL;
+	g_autoptr(GPtrArray) icons = NULL;  /* (element-type XbNode) */
+
+	icons = xb_node_query (component, "icon", 0, &local_error);
+	traverse_component_icons (app, component, icons);
+	g_clear_pointer (&icons, g_ptr_array_unref);
+
+	/* If no icon found, try to inherit the icon from the .desktop file */
+	if (gs_app_get_icons (app) == NULL) {
+		g_autofree gchar *xpath = NULL;
+		const gchar *launchable_id = xb_node_query_text (component, "launchable[@type='desktop-id']", NULL);
+		if (launchable_id != NULL) {
+			xpath = g_strdup_printf ("/component[@type='desktop-application']/launchable[@type='desktop-id'][text()='%s']/..",
+						 launchable_id);
+			traverse_components_xpath_for_icons (app, silo, xpath, FALSE);
+			g_clear_pointer (&xpath, g_free);
+		}
+
+		xpath = g_strdup_printf ("/component[@type='desktop-application']/launchable[@type='desktop-id'][text()='%s']/..",
+					 gs_app_get_id (app));
+		traverse_components_xpath_for_icons (app, silo, xpath, FALSE);
+	}
+}
+
+static gboolean
+gs_appstream_refine_add_addons (GsPlugin *plugin,
+				GsApp *app,
+				XbSilo *silo,
+				GError **error)
+{
+	g_autofree gchar *xpath = NULL;
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GPtrArray) addons = NULL;
+	g_autoptr(GsAppList) addons_list = NULL;
+
+	/* get all components */
+	xpath = g_strdup_printf ("components/component/extends[text()='%s']/..",
+				 gs_app_get_id (app));
+	addons = xb_silo_query (silo, xpath, 0, &error_local);
+	if (addons == NULL) {
+		if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+			return TRUE;
+		g_propagate_error (error, g_steal_pointer (&error_local));
+		return FALSE;
+	}
+
+	addons_list = gs_app_list_new ();
+
+	for (guint i = 0; i < addons->len; i++) {
+		XbNode *addon = g_ptr_array_index (addons, i);
+		g_autoptr(GsApp) addon_app = NULL;
+
+		addon_app = gs_appstream_create_app (plugin, silo, addon, error);
+		if (addon_app == NULL)
+			return FALSE;
+
+		gs_app_list_add (addons_list, addon_app);
+	}
+
+	gs_app_add_addons (app, addons_list);
+
+	return TRUE;
+}
+
+static gboolean
+gs_appstream_refine_add_images (GsApp *app,
+				AsScreenshot *ss,
+				XbNode *screenshot,
+				gboolean *out_any_added,
+				GError **error)
+{
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GPtrArray) images = NULL;
+
+	/* get all components */
+	images = xb_node_query (screenshot, "image", 0, &error_local);
+	if (images == NULL) {
+		if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+			return TRUE;
+		g_propagate_error (error, g_steal_pointer (&error_local));
+		return FALSE;
+	}
+	for (guint i = 0; i < images->len; i++) {
+		XbNode *image = g_ptr_array_index (images, i);
+		g_autoptr(AsImage) im = as_image_new ();
+		as_image_set_height (im, xb_node_get_attr_as_uint (image, "height"));
+		as_image_set_width (im, xb_node_get_attr_as_uint (image, "width"));
+		as_image_set_kind (im, as_image_kind_from_string (xb_node_get_attr (image, "type")));
+		as_image_set_url (im, xb_node_get_text (image));
+		as_screenshot_add_image (ss, im);
+	}
+
+	*out_any_added = *out_any_added || images->len > 0;
+
+	/* success */
+	return TRUE;
+}
+
+static gboolean
+gs_appstream_refine_add_videos (GsApp *app,
+				AsScreenshot *ss,
+				XbNode *screenshot,
+				gboolean *out_any_added,
+				GError **error)
+{
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GPtrArray) videos = NULL;
+
+	videos = xb_node_query (screenshot, "video", 0, &error_local);
+	if (videos == NULL) {
+		if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+			return TRUE;
+		g_propagate_error (error, g_steal_pointer (&error_local));
+		return FALSE;
+	}
+	for (guint i = 0; i < videos->len; i++) {
+		XbNode *video = g_ptr_array_index (videos, i);
+		g_autoptr(AsVideo) vid = as_video_new ();
+		as_video_set_height (vid, xb_node_get_attr_as_uint (video, "height"));
+		as_video_set_width (vid, xb_node_get_attr_as_uint (video, "width"));
+		as_video_set_codec_kind (vid, as_video_codec_kind_from_string (xb_node_get_attr (video, "codec")));
+		as_video_set_container_kind (vid, as_video_container_kind_from_string (xb_node_get_attr (video, "container")));
+		as_video_set_url (vid, xb_node_get_text (video));
+		as_screenshot_add_video (ss, vid);
+	}
+
+	*out_any_added = *out_any_added || videos->len > 0;
+
+	return TRUE;
+}
+
+static gboolean
+gs_appstream_refine_add_screenshots (GsApp *app, XbNode *component, GError **error)
+{
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GPtrArray) screenshots = NULL;
+
+	/* get all components */
+	screenshots = xb_node_query (component, "screenshots/screenshot", 0, &error_local);
+	if (screenshots == NULL) {
+		if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+			return TRUE;
+		g_propagate_error (error, g_steal_pointer (&error_local));
+		return FALSE;
+	}
+	for (guint i = 0; i < screenshots->len; i++) {
+		XbNode *screenshot = g_ptr_array_index (screenshots, i);
+		g_autoptr(AsScreenshot) ss = as_screenshot_new ();
+		gboolean any_added = FALSE;
+		if (!gs_appstream_refine_add_images (app, ss, screenshot, &any_added, error) ||
+		    !gs_appstream_refine_add_videos (app, ss, screenshot, &any_added, error))
+			return FALSE;
+		if (any_added)
+			gs_app_add_screenshot (app, ss);
+	}
+
+	/* FIXME: move into no refine flags section? */
+	if (screenshots ->len > 0)
+		gs_app_add_kudo (app, GS_APP_KUDO_HAS_SCREENSHOTS);
+
+	/* success */
+	return TRUE;
+}
+
+static gboolean
+gs_appstream_refine_add_provides (GsApp *app, XbNode *component, GError **error)
+{
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GPtrArray) provides = NULL;
+
+	/* get all components */
+	provides = xb_node_query (component, "provides/*", 0, &error_local);
+	if (provides == NULL) {
+		if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+			return TRUE;
+		g_propagate_error (error, g_steal_pointer (&error_local));
+		return FALSE;
+	}
+	for (guint i = 0; i < provides->len; i++) {
+		AsProvidedKind kind;
+		const gchar *element_name;
+		XbNode *provide = g_ptr_array_index (provides, i);
+		element_name = xb_node_get_element (provide);
+
+		/* try the simple case */
+		kind = as_provided_kind_from_string (element_name);
+		if (kind == AS_PROVIDED_KIND_UNKNOWN) {
+			/* try the complex cases */
+
+			if (g_strcmp0 (element_name, "library") == 0) {
+				kind = AS_PROVIDED_KIND_LIBRARY;
+			} else if (g_strcmp0 (element_name, "binary") == 0) {
+				kind = AS_PROVIDED_KIND_BINARY;
+			} else if (g_strcmp0 (element_name, "firmware") == 0) {
+				const gchar *fw_type = xb_node_get_attr (provide, "type");
+				if (g_strcmp0 (fw_type, "runtime") == 0)
+					kind = AS_PROVIDED_KIND_FIRMWARE_RUNTIME;
+				else if (g_strcmp0 (fw_type, "flashed") == 0)
+					kind = AS_PROVIDED_KIND_FIRMWARE_FLASHED;
+			} else if (g_strcmp0 (element_name, "python2") == 0) {
+				kind = AS_PROVIDED_KIND_PYTHON_2;
+			} else if (g_strcmp0 (element_name, "python3") == 0) {
+				kind = AS_PROVIDED_KIND_PYTHON;
+			} else if (g_strcmp0 (element_name, "dbus") == 0) {
+				const gchar *dbus_type = xb_node_get_attr (provide, "type");
+				if (g_strcmp0 (dbus_type, "system") == 0)
+					kind = AS_PROVIDED_KIND_DBUS_SYSTEM;
+				else if ((g_strcmp0 (dbus_type, "user") == 0) || (g_strcmp0 (dbus_type, "session") == 0))
+					kind = AS_PROVIDED_KIND_DBUS_USER;
+			}
+		}
+
+		if (kind == AS_PROVIDED_KIND_UNKNOWN ||
+		    xb_node_get_text (provide) == NULL) {
+			/* give up */
+			g_warning ("ignoring unknown or empty provided item type: %s", element_name);
+			continue;
+		}
+
+		gs_app_add_provided_item (app,
+					  kind,
+					  xb_node_get_text (provide));
+	}
+
+	/* success */
+	return TRUE;
+}
+
+static guint64
+component_get_release_timestamp (XbNode *component)
+{
+	guint64 timestamp;
+	const gchar *date_str;
+
+	/* Spec says to prefer `timestamp` over `date` if both are provided:
+	 * https://www.freedesktop.org/software/appstream/docs/chap-Metadata.html#tag-releases */
+	timestamp = xb_node_query_attr_as_uint (component, "releases/release", "timestamp", NULL);
+	date_str = xb_node_query_attr (component, "releases/release", "date", NULL);
+
+	if (timestamp != G_MAXUINT64) {
+		return timestamp;
+	} else if (date_str != NULL) {
+		g_autoptr(GDateTime) date = g_date_time_new_from_iso8601 (date_str, NULL);
+		if (date != NULL)
+			return g_date_time_to_unix (date);
+	}
+
+	/* Unknown. */
+	return G_MAXUINT64;
+}
+
+static gboolean
+gs_appstream_is_recent_release (XbNode *component)
+{
+	guint64 ts;
+	gint64 secs;
+
+	/* get newest release */
+	ts = component_get_release_timestamp (component);
+	if (ts == G_MAXUINT64)
+		return FALSE;
+
+	/* is last build less than one year ago? */
+	secs = (g_get_real_time () / G_USEC_PER_SEC) - ts;
+	return secs / (60 * 60 * 24) < 365;
+}
+
+static gboolean
+gs_appstream_copy_metadata (GsApp *app, XbNode *component, GError **error)
+{
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GPtrArray) values = NULL;
+
+	/* get all components */
+	values = xb_node_query (component, "custom/value", 0, &error_local);
+	if (values == NULL) {
+		if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+			return TRUE;
+		g_propagate_error (error, g_steal_pointer (&error_local));
+		return FALSE;
+	}
+	for (guint i = 0; i < values->len; i++) {
+		XbNode *value = g_ptr_array_index (values, i);
+		const gchar *key = xb_node_get_attr (value, "key");
+		if (key == NULL)
+			continue;
+		if (gs_app_get_metadata_item (app, key) != NULL)
+			continue;
+		gs_app_set_metadata (app, key, xb_node_get_text (value));
+	}
+	return TRUE;
+}
+
+static gboolean
+gs_appstream_refine_app_updates (GsApp *app,
+				 XbSilo *silo,
+				 XbNode *component,
+				 GError **error)
+{
+	AsUrgencyKind urgency_best = AS_URGENCY_KIND_UNKNOWN;
+	g_autofree gchar *xpath = NULL;
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GHashTable) installed = g_hash_table_new (g_str_hash, g_str_equal);
+	g_autoptr(GPtrArray) releases_inst = NULL;
+	g_autoptr(GPtrArray) releases = NULL;
+	g_autoptr(GPtrArray) updates_list = g_ptr_array_new ();
+
+	/* only for UPDATABLE apps */
+	if (!gs_app_is_updatable (app))
+		return TRUE;
+
+	/* find out which releases are already installed */
+	xpath = g_strdup_printf ("component/id[text()='%s']/../releases/*[@version]",
+				 gs_app_get_id (app));
+	releases_inst = xb_silo_query (silo, xpath, 0, &error_local);
+	if (releases_inst == NULL) {
+		if (!g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND)) {
+			g_propagate_error (error, g_steal_pointer (&error_local));
+			return FALSE;
+		}
+	} else {
+		for (guint i = 0; i < releases_inst->len; i++) {
+			XbNode *release = g_ptr_array_index (releases_inst, i);
+			g_hash_table_insert (installed,
+					     (gpointer) xb_node_get_attr (release, "version"),
+					     (gpointer) release);
+		}
+	}
+	g_clear_error (&error_local);
+
+	/* get all components */
+	releases = xb_node_query (component, "releases/*", 0, &error_local);
+	if (releases == NULL) {
+		if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+			return TRUE;
+		g_propagate_error (error, g_steal_pointer (&error_local));
+		return FALSE;
+	}
+	for (guint i = 0; i < releases->len; i++) {
+		XbNode *release = g_ptr_array_index (releases, i);
+		const gchar *version = xb_node_get_attr (release, "version");
+		g_autoptr(XbNode) description = NULL;
+		AsUrgencyKind urgency_tmp;
+
+		/* ignore releases with no version */
+		if (version == NULL)
+			continue;
+
+		/* already installed */
+		if (g_hash_table_lookup (installed, version) != NULL)
+			continue;
+
+		/* limit this to three versions backwards if there has never
+		 * been a detected installed version */
+		if (g_hash_table_size (installed) == 0 && i >= 3)
+			break;
+
+		/* use the 'worst' urgency, e.g. critical over enhancement */
+		urgency_tmp = as_urgency_kind_from_string (xb_node_get_attr (release, "urgency"));
+		if (urgency_tmp > urgency_best)
+			urgency_best = urgency_tmp;
+
+		/* add updates with a description */
+		description = xb_node_query_first (release, "description", NULL);
+		if (description == NULL)
+			continue;
+		g_ptr_array_add (updates_list, release);
+	}
+
+	/* only set if known */
+	if (urgency_best != AS_URGENCY_KIND_UNKNOWN)
+		gs_app_set_update_urgency (app, urgency_best);
+
+	/* no prefix on each release */
+	if (updates_list->len == 1) {
+		XbNode *release = g_ptr_array_index (updates_list, 0);
+		g_autoptr(XbNode) n = NULL;
+		g_autofree gchar *desc = NULL;
+		n = xb_node_query_first (release, "description", NULL);
+		desc = gs_appstream_format_description (n, NULL);
+		gs_app_set_update_details_markup (app, desc);
+
+	/* get the descriptions with a version prefix */
+	} else if (updates_list->len > 1) {
+		const gchar *version = gs_app_get_version (app);
+		g_autoptr(GString) update_desc = g_string_new ("");
+		for (guint i = 0; i < updates_list->len; i++) {
+			XbNode *release = g_ptr_array_index (updates_list, i);
+			const gchar *release_version = xb_node_get_attr (release, "version");
+			g_autofree gchar *desc = NULL;
+			g_autoptr(XbNode) n = NULL;
+
+			/* skip the currently installed version and all below it */
+			if (version != NULL && as_vercmp_simple (version, release_version) >= 0)
+				continue;
+
+			n = xb_node_query_first (release, "description", NULL);
+			desc = gs_appstream_format_description (n, NULL);
+			g_string_append_printf (update_desc,
+						"Version %s:\n%s\n\n",
+						xb_node_get_attr (release, "version"),
+						desc);
+		}
+
+		/* remove trailing newlines */
+		if (update_desc->len > 2)
+			g_string_truncate (update_desc, update_desc->len - 2);
+		if (update_desc->len > 0)
+			gs_app_set_update_details_markup (app, update_desc->str);
+	}
+
+	/* if there is no already set update version use the newest */
+	if (gs_app_get_update_version (app) == NULL &&
+	    updates_list->len > 0) {
+		XbNode *release = g_ptr_array_index (updates_list, 0);
+		gs_app_set_update_version (app, xb_node_get_attr (release, "version"));
+	}
+
+	/* success */
+	return TRUE;
+}
+
+static gboolean
+gs_appstream_refine_add_version_history (GsApp *app, XbNode *component, GError **error)
+{
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GPtrArray) version_history = NULL; /* (element-type AsRelease) */
+	g_autoptr(GPtrArray) releases = NULL; /* (element-type XbNode) */
+
+	/* get all components */
+	releases = xb_node_query (component, "releases/*", 0, &error_local);
+	if (releases == NULL) {
+		if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+			return TRUE;
+		g_propagate_error (error, g_steal_pointer (&error_local));
+		return FALSE;
+	}
+
+	version_history = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);
+	for (guint i = 0; i < releases->len; i++) {
+		XbNode *release_node = g_ptr_array_index (releases, i);
+		const gchar *version = xb_node_get_attr (release_node, "version");
+		g_autoptr(XbNode) description_node = NULL;
+		g_autofree gchar *description = NULL;
+		guint64 timestamp;
+		const gchar *date_str;
+		g_autoptr(AsRelease) release = NULL;
+		g_autofree char *timestamp_xpath = NULL;
+
+		/* ignore releases with no version */
+		if (version == NULL)
+			continue;
+
+		timestamp_xpath = g_strdup_printf ("releases/release[%u]", i+1);
+		timestamp = xb_node_query_attr_as_uint (component, timestamp_xpath, "timestamp", NULL);
+		date_str = xb_node_query_attr (component, timestamp_xpath, "date", NULL);
+
+		/* include updates with or without a description */
+		description_node = xb_node_query_first (release_node, "description", NULL);
+		if (description_node != NULL)
+			description = gs_appstream_format_description (description_node, NULL);
+
+		release = as_release_new ();
+		as_release_set_version (release, version);
+		if (timestamp != G_MAXUINT64)
+			as_release_set_timestamp (release, timestamp);
+		else if (date_str != NULL)  /* timestamp takes precedence over date */
+			as_release_set_date (release, date_str);
+		if (description != NULL)
+			as_release_set_description (release, description, NULL);
+
+		g_ptr_array_add (version_history, g_steal_pointer (&release));
+	}
+
+	if (version_history->len > 0)
+		gs_app_set_version_history (app, version_history);
+
+	/* success */
+	return TRUE;
+}
+
+/**
+ * _gs_utils_locale_has_translations:
+ * @locale: A locale, e.g. `en_GB` or `uz_UZ.utf8@cyrillic`
+ *
+ * Looks up if the locale is likely to have translations.
+ *
+ * Returns: %TRUE if the locale should have translations
+ **/
+static gboolean
+_gs_utils_locale_has_translations (const gchar *locale)
+{
+	g_autofree gchar *locale_copy = g_strdup (locale);
+	gchar *separator;
+
+	/* Strip off the territory, codeset and modifier, if present. */
+	separator = strpbrk (locale_copy, "_.@");
+	if (separator != NULL)
+		*separator = '\0';
+
+	if (g_strcmp0 (locale_copy, "C") == 0)
+		return FALSE;
+	if (g_strcmp0 (locale_copy, "en") == 0)
+		return FALSE;
+	return TRUE;
+}
+
+static gboolean
+gs_appstream_origin_valid (const gchar *origin)
+{
+	if (origin == NULL)
+		return FALSE;
+	if (g_strcmp0 (origin, "") == 0)
+		return FALSE;
+	return TRUE;
+}
+
+static gboolean
+gs_appstream_is_valid_project_group (const gchar *project_group)
+{
+	if (project_group == NULL)
+		return FALSE;
+	return as_utils_is_desktop_environment (project_group);
+}
+
+static gboolean
+gs_appstream_refine_app_content_rating (GsApp *app,
+					XbNode *content_rating,
+					GError **error)
+{
+	g_autoptr(AsContentRating) cr = as_content_rating_new ();
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GPtrArray) content_attributes = NULL;
+	const gchar *content_rating_kind = NULL;
+
+	/* get kind */
+	content_rating_kind = xb_node_get_attr (content_rating, "type");
+	/* we only really expect/support OARS 1.0 and 1.1 */
+	if (content_rating_kind == NULL ||
+	    (g_strcmp0 (content_rating_kind, "oars-1.0") != 0 &&
+	     g_strcmp0 (content_rating_kind, "oars-1.1") != 0)) {
+		return TRUE;
+	}
+
+	as_content_rating_set_kind (cr, content_rating_kind);
+
+	/* get attributes; no attributes being found (i.e.
+	 * `<content_rating type="*"/>`) is OK: it means that all attributes have
+	 * value `none`, as per the
+	 * [OARS semantics](https://github.com/hughsie/oars/blob/HEAD/specification/oars-1.1.md) */
+	content_attributes = xb_node_query (content_rating, "content_attribute", 0, &error_local);
+	if (content_attributes == NULL &&
+	    g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND)) {
+		g_clear_error (&error_local);
+	} else if (content_attributes == NULL) {
+		g_propagate_error (error, g_steal_pointer (&error_local));
+		return FALSE;
+	}
+
+	for (guint i = 0; content_attributes != NULL && i < content_attributes->len; i++) {
+		XbNode *content_attribute = g_ptr_array_index (content_attributes, i);
+		as_content_rating_add_attribute (cr,
+						 xb_node_get_attr (content_attribute, "id"),
+						 as_content_rating_value_from_string (xb_node_get_text (content_attribute)));
+	}
+
+	gs_app_set_content_rating (app, cr);
+	return TRUE;
+}
+
+static gboolean
+gs_appstream_refine_app_content_ratings (GsApp *app,
+					 XbNode *component,
+					 GError **error)
+{
+	g_autoptr(GPtrArray) content_ratings = NULL;
+	g_autoptr(GError) error_local = NULL;
+
+	/* find any content ratings */
+	content_ratings = xb_node_query (component, "content_rating", 0, &error_local);
+	if (content_ratings == NULL) {
+		if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+			return TRUE;
+		g_propagate_error (error, g_steal_pointer (&error_local));
+		return FALSE;
+	}
+	for (guint i = 0; i < content_ratings->len; i++) {
+		XbNode *content_rating = g_ptr_array_index (content_ratings, i);
+		if (!gs_appstream_refine_app_content_rating (app, content_rating, error))
+			return FALSE;
+	}
+	return TRUE;
+}
+
+static gboolean
+gs_appstream_refine_app_relation (GsApp           *app,
+                                  XbNode          *relation_node,
+                                  AsRelationKind   kind,
+                                  GError         **error)
+{
+	/* Iterate over the children, which might be any combination of zero or
+	 * more <id/>, <modalias/>, <kernel/>, <memory/>, <firmware/>,
+	 * <control/> or <display_length/> elements. For the moment, we only
+	 * support some of these. */
+	for (g_autoptr(XbNode) child = xb_node_get_child (relation_node); child != NULL; node_set_to_next (&child)) {
+		const gchar *item_kind = xb_node_get_element (child);
+		g_autoptr(AsRelation) relation = as_relation_new ();
+
+		as_relation_set_kind (relation, kind);
+
+		if (g_str_equal (item_kind, "control")) {
+			/* https://www.freedesktop.org/software/appstream/docs/chap-Metadata.html#tag-relations-control */
+			as_relation_set_item_kind (relation, AS_RELATION_ITEM_KIND_CONTROL);
+			as_relation_set_value_control_kind (relation, as_control_kind_from_string (xb_node_get_text (child)));
+		} else if (g_str_equal (item_kind, "display_length")) {
+			AsDisplayLengthKind display_length_kind;
+			const gchar *compare;
+
+			/* https://www.freedesktop.org/software/appstream/docs/chap-Metadata.html#tag-relations-display_length */
+			as_relation_set_item_kind (relation, AS_RELATION_ITEM_KIND_DISPLAY_LENGTH);
+
+			compare = xb_node_get_attr (child, "compare");
+			as_relation_set_compare (relation, (compare != NULL) ? as_relation_compare_from_string (compare) : AS_RELATION_COMPARE_GE);
+
+			display_length_kind = as_display_length_kind_from_string (xb_node_get_text (child));
+			if (display_length_kind != AS_DISPLAY_LENGTH_KIND_UNKNOWN) {
+				/* Ignore the `side` attribute */
+				as_relation_set_value_display_length_kind (relation, display_length_kind);
+			} else {
+				const gchar *side = xb_node_get_attr (child, "side");
+				as_relation_set_display_side_kind (relation, (side != NULL) ? as_display_side_kind_from_string (side) : AS_DISPLAY_SIDE_KIND_SHORTEST);
+				as_relation_set_value_px (relation, xb_node_get_text_as_uint (child));
+			}
+		} else {
+			g_debug ("Relation type ‘%s’ not currently supported for %s; ignoring",
+				 item_kind, gs_app_get_id (app));
+			continue;
+		}
+
+		gs_app_add_relation (app, relation);
+	}
+
+	return TRUE;
+}
+
+static gboolean
+gs_appstream_refine_app_relations (GsApp     *app,
+                                   XbNode    *component,
+                                   GError   **error)
+{
+	const struct {
+		const gchar *element_name;
+		AsRelationKind relation_kind;
+	} relation_types[] = {
+#if AS_CHECK_VERSION(0, 15, 0)
+		{ "supports", AS_RELATION_KIND_SUPPORTS },
+#endif
+		{ "recommends", AS_RELATION_KIND_RECOMMENDS },
+		{ "requires", AS_RELATION_KIND_REQUIRES },
+	};
+
+	for (gsize i = 0; i < G_N_ELEMENTS (relation_types); i++) {
+		g_autoptr(GPtrArray) relations = NULL;
+		g_autoptr(GError) error_local = NULL;
+
+		/* find any instances of this @element_name */
+		relations = xb_node_query (component, relation_types[i].element_name, 0, &error_local);
+		if (relations == NULL &&
+		    !g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND)) {
+			g_propagate_error (error, g_steal_pointer (&error_local));
+			return FALSE;
+		}
+
+		for (guint j = 0; relations != NULL && j < relations->len; j++) {
+			XbNode *relation = g_ptr_array_index (relations, j);
+			if (!gs_appstream_refine_app_relation (app, relation, relation_types[i].relation_kind, error))
+				return FALSE;
+		}
+	}
+
+	return TRUE;
+}
+
+gboolean
+gs_appstream_refine_app (GsPlugin *plugin,
+			 GsApp *app,
+			 XbSilo *silo,
+			 XbNode *component,
+			 GsPluginRefineFlags refine_flags,
+			 GError **error)
+{
+	const gchar *tmp;
+	guint64 timestamp;
+	g_autoptr(GPtrArray) bundles = NULL;
+	g_autoptr(GPtrArray) launchables = NULL;
+	g_autoptr(XbNode) req = NULL;
+
+	/* The 'plugin' can be NULL, when creating app for --show-metainfo */
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+	g_return_val_if_fail (XB_IS_SILO (silo), FALSE);
+	g_return_val_if_fail (XB_IS_NODE (component), FALSE);
+
+	/* is compatible */
+	req = xb_node_query_first (component,
+				   "requires/id[@type='id']"
+				   "[text()='org.gnome.Software.desktop']", NULL);
+	if (req != NULL) {
+		gint rc = as_vercmp_simple (xb_node_get_attr (req, "version"),
+					    PACKAGE_VERSION);
+		if (rc > 0) {
+			g_set_error (error,
+				     GS_PLUGIN_ERROR,
+				     GS_PLUGIN_ERROR_NOT_SUPPORTED,
+				     "not for this gnome-software");
+			return FALSE;
+		}
+	}
+
+	/* set id kind */
+	if (gs_app_get_kind (app) == AS_COMPONENT_KIND_UNKNOWN ||
+	    gs_app_get_kind (app) == AS_COMPONENT_KIND_GENERIC) {
+		AsComponentKind kind;
+		tmp = xb_node_get_attr (component, "type");
+		kind = as_component_kind_from_string (tmp);
+		if (kind != AS_COMPONENT_KIND_UNKNOWN)
+			gs_app_set_kind (app, kind);
+	}
+
+	/* types we can never launch */
+	switch (gs_app_get_kind (app)) {
+	case AS_COMPONENT_KIND_ADDON:
+	case AS_COMPONENT_KIND_CODEC:
+	case AS_COMPONENT_KIND_DRIVER:
+	case AS_COMPONENT_KIND_FIRMWARE:
+	case AS_COMPONENT_KIND_FONT:
+	case AS_COMPONENT_KIND_GENERIC:
+	case AS_COMPONENT_KIND_INPUT_METHOD:
+	case AS_COMPONENT_KIND_LOCALIZATION:
+	case AS_COMPONENT_KIND_OPERATING_SYSTEM:
+	case AS_COMPONENT_KIND_RUNTIME:
+	case AS_COMPONENT_KIND_REPOSITORY:
+		gs_app_add_quirk (app, GS_APP_QUIRK_NOT_LAUNCHABLE);
+		break;
+	default:
+		break;
+	}
+
+	/* check if the special metadata affects the not-launchable quirk */
+	tmp = gs_app_get_metadata_item (app, "GnomeSoftware::quirks::not-launchable");
+	if (tmp != NULL) {
+		if (g_strcmp0 (tmp, "true") == 0)
+			gs_app_add_quirk (app, GS_APP_QUIRK_NOT_LAUNCHABLE);
+		else if (g_strcmp0 (tmp, "false") == 0)
+			gs_app_remove_quirk (app, GS_APP_QUIRK_NOT_LAUNCHABLE);
+	}
+
+	tmp = gs_app_get_metadata_item (app, "GnomeSoftware::quirks::hide-everywhere");
+	if (tmp != NULL) {
+		if (g_strcmp0 (tmp, "true") == 0)
+			gs_app_add_quirk (app, GS_APP_QUIRK_HIDE_EVERYWHERE);
+		else if (g_strcmp0 (tmp, "false") == 0)
+			gs_app_remove_quirk (app, GS_APP_QUIRK_HIDE_EVERYWHERE);
+	}
+
+	/* try to detect old-style AppStream 'override'
+	 * files without the merge attribute */
+	if (xb_node_query_text (component, "name", NULL) == NULL &&
+	    xb_node_query_text (component, "metadata_license", NULL) == NULL) {
+		gs_app_add_quirk (app, GS_APP_QUIRK_IS_WILDCARD);
+	}
+
+	/* set id */
+	tmp = xb_node_query_text (component, "id", NULL);
+	if (tmp != NULL && gs_app_get_id (app) == NULL)
+		gs_app_set_id (app, tmp);
+
+	/* set source */
+	tmp = xb_node_query_text (component, "info/filename", NULL);
+	if (tmp == NULL)
+		tmp = xb_node_query_text (component, "../info/filename", NULL);
+	if (tmp != NULL && gs_app_get_metadata_item (app, "appstream::source-file") == NULL) {
+		gs_app_set_metadata (app, "appstream::source-file", tmp);
+	}
+
+	/* set scope */
+	tmp = xb_node_query_text (component, "../info/scope", NULL);
+	if (tmp != NULL)
+		gs_app_set_scope (app, as_component_scope_from_string (tmp));
+
+	/* set content rating */
+	if (TRUE) {
+		if (!gs_appstream_refine_app_content_ratings (app, component, error))
+			return FALSE;
+	}
+
+	/* recommends/requires
+	 * FIXME: Technically this could do with a more specific refine flag,
+	 * but essentially the relations are used on the details page and so
+	 * are the permissions. It would be good to eliminate refine flags at
+	 * some point in the future. */
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_PERMISSIONS) {
+		if (!gs_appstream_refine_app_relations (app, component, error))
+			return FALSE;
+	}
+
+	/* set name */
+	tmp = xb_node_query_text (component, "name", NULL);
+	if (tmp != NULL)
+		gs_app_set_name (app, GS_APP_QUALITY_HIGHEST, tmp);
+
+	/* set summary */
+	tmp = xb_node_query_text (component, "summary", NULL);
+	if (tmp != NULL)
+		gs_app_set_summary (app, GS_APP_QUALITY_HIGHEST, tmp);
+
+	/* add urls */
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_URL) {
+		g_autoptr(GPtrArray) urls = NULL;
+		urls = xb_node_query (component, "url", 0, NULL);
+		if (urls != NULL) {
+			for (guint i = 0; i < urls->len; i++) {
+				XbNode *url = g_ptr_array_index (urls, i);
+				const gchar *kind = xb_node_get_attr (url, "type");
+				if (kind == NULL)
+					continue;
+				gs_app_set_url (app,
+						as_url_kind_from_string (kind),
+						xb_node_get_text (url));
+			}
+		}
+	}
+
+	/* add launchables */
+	launchables = xb_node_query (component, "launchable", 0, NULL);
+	if (launchables != NULL) {
+		for (guint i = 0; i < launchables->len; i++) {
+			XbNode *launchable = g_ptr_array_index (launchables, i);
+			const gchar *kind = xb_node_get_attr (launchable, "type");
+			if (g_strcmp0 (kind, "desktop-id") == 0) {
+				gs_app_set_launchable (app,
+						       AS_LAUNCHABLE_KIND_DESKTOP_ID,
+						       xb_node_get_text (launchable));
+				break;
+			} else if (g_strcmp0 (kind, "url") == 0) {
+				gs_app_set_launchable (app,
+						       AS_LAUNCHABLE_KIND_URL,
+						       xb_node_get_text (launchable));
+			}
+		}
+	}
+
+	/* set license */
+	if ((refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_LICENSE) > 0 &&
+	    gs_app_get_license (app) == NULL) {
+		tmp = xb_node_query_text (component, "project_license", NULL);
+		if (tmp != NULL)
+			gs_app_set_license (app, GS_APP_QUALITY_HIGHEST, tmp);
+	}
+
+	/* set description */
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_DESCRIPTION) {
+		g_autofree gchar *description = NULL;
+		g_autoptr(XbNode) n = xb_node_query_first (component, "description", NULL);
+		if (n != NULL)
+			description = gs_appstream_format_description (n, NULL);
+		if (description != NULL)
+			gs_app_set_description (app, GS_APP_QUALITY_HIGHEST, description);
+	}
+
+	/* set icon */
+	if ((refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_ICON) > 0 &&
+	    gs_app_get_icons (app) == NULL)
+		gs_appstream_refine_icon (app, silo, component);
+
+	/* set categories */
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_CATEGORIES) {
+		g_autoptr(GPtrArray) categories = NULL;
+		categories = xb_node_query (component, "categories/category", 0, NULL);
+		if (categories != NULL) {
+			for (guint i = 0; i < categories->len; i++) {
+				XbNode *category = g_ptr_array_index (categories, i);
+				gs_app_add_category (app, xb_node_get_text (category));
+
+				/* Special case: We used to use the `Blacklisted`
+				 * category to hide apps from their .desktop
+				 * file or appdata. We now use a quirk for that.
+				 * This special case can be removed when all
+				 * appstream files no longer use the `Blacklisted`
+				 * category (including external-appstream files
+				 * put together by distributions). */
+				if (g_strcmp0 (xb_node_get_text (category), "Blacklisted") == 0)
+					gs_app_add_quirk (app, GS_APP_QUIRK_HIDE_EVERYWHERE);
+			}
+		}
+	}
+
+	/* set project group */
+	if ((refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_PROJECT_GROUP) > 0 &&
+	    gs_app_get_project_group (app) == NULL) {
+		tmp = xb_node_query_text (component, "project_group", NULL);
+		if (tmp != NULL && gs_appstream_is_valid_project_group (tmp))
+			gs_app_set_project_group (app, tmp);
+	}
+
+	/* set developer name */
+	if ((refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_DEVELOPER_NAME) > 0 &&
+	    gs_app_get_developer_name (app) == NULL) {
+		tmp = xb_node_query_text (component, "developer_name", NULL);
+		if (tmp != NULL)
+			gs_app_set_developer_name (app, tmp);
+	}
+
+	/* set the release date */
+	timestamp = component_get_release_timestamp (component);
+	if (timestamp != G_MAXUINT64)
+		gs_app_set_release_date (app, timestamp);
+
+	/* set the version history */
+	if (!gs_appstream_refine_add_version_history (app, component, error))
+		return FALSE;
+
+	/* copy all the metadata */
+	if (!gs_appstream_copy_metadata (app, component, error))
+		return FALSE;
+
+	/* add bundles */
+	bundles = xb_node_query (component, "bundle", 0, NULL);
+	if (bundles != NULL && gs_app_get_sources(app)->len == 0) {
+		for (guint i = 0; i < bundles->len; i++) {
+			XbNode *bundle = g_ptr_array_index (bundles, i);
+			const gchar *kind = xb_node_get_attr (bundle, "type");
+			const gchar *bundle_id = xb_node_get_text (bundle);
+
+			if (bundle_id == NULL || kind == NULL)
+				continue;
+
+			gs_app_add_source (app, bundle_id);
+			gs_app_set_bundle_kind (app, as_bundle_kind_from_string (kind));
+
+			/* get the type/name/arch/branch */
+			if (gs_app_get_bundle_kind (app) == AS_BUNDLE_KIND_FLATPAK) {
+				g_auto(GStrv) split = g_strsplit (bundle_id, "/", -1);
+				if (g_strv_length (split) != 4) {
+					g_set_error (error,
+						     GS_PLUGIN_ERROR,
+						     GS_PLUGIN_ERROR_NOT_SUPPORTED,
+						     "invalid ID %s for a flatpak ref",
+						     bundle_id);
+					return FALSE;
+				}
+
+				/* we only need the branch for the unique ID */
+				gs_app_set_branch (app, split[3]);
+			}
+		}
+	}
+
+	/* add legacy package names */
+	if (gs_app_get_bundle_kind (app) == AS_BUNDLE_KIND_UNKNOWN) {
+		g_autoptr(GPtrArray) pkgnames = NULL;
+		pkgnames = xb_node_query (component, "pkgname", 0, NULL);
+		if (pkgnames != NULL && gs_app_get_sources(app)->len == 0) {
+			for (guint i = 0; i < pkgnames->len; i++) {
+				XbNode *pkgname = g_ptr_array_index (pkgnames, i);
+				tmp = xb_node_get_text (pkgname);
+				if (tmp != NULL && tmp[0] != '\0')
+					gs_app_add_source (app, tmp);
+			}
+			gs_app_set_bundle_kind (app, AS_BUNDLE_KIND_PACKAGE);
+		}
+	}
+
+	/* set origin */
+	tmp = xb_node_query_attr (component, "..", "origin", NULL);
+	if (gs_appstream_origin_valid (tmp)) {
+		gs_app_set_origin_appstream (app, tmp);
+
+		if (gs_app_get_origin (app) == NULL && (
+		    gs_app_get_bundle_kind (app) == AS_BUNDLE_KIND_FLATPAK ||
+		    gs_app_get_bundle_kind (app) == AS_BUNDLE_KIND_PACKAGE)) {
+			gs_app_set_origin (app, tmp);
+		}
+	}
+
+	/* set addons */
+	if ((refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_ADDONS) != 0 &&
+	    plugin != NULL && silo != NULL) {
+		if (!gs_appstream_refine_add_addons (plugin, app, silo, error))
+			return FALSE;
+	}
+
+	/* set screenshots */
+	if ((refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_SCREENSHOTS) > 0 &&
+	    gs_app_get_screenshots(app)->len == 0) {
+		if (!gs_appstream_refine_add_screenshots (app, component, error))
+			return FALSE;
+	}
+
+	/* set provides */
+	if (!gs_appstream_refine_add_provides (app, component, error))
+		return FALSE;
+
+	/* add kudos */
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_KUDOS) {
+		g_autoptr(GPtrArray) kudos = NULL;
+		tmp = setlocale (LC_MESSAGES, NULL);
+		if (!_gs_utils_locale_has_translations (tmp)) {
+			gs_app_add_kudo (app, GS_APP_KUDO_MY_LANGUAGE);
+		} else {
+
+			g_autoptr(GString) xpath = g_string_new (NULL);
+			g_auto(GStrv) variants = g_get_locale_variants (tmp);
+
+			/* @variants includes @tmp */
+			for (gsize i = 0; variants[i] != NULL; i++)
+				xb_string_append_union (xpath, "languages/lang[(text()='%s') and (@percentage>50)]", variants[i]);
+
+			if (xb_node_query_text (component, xpath->str, NULL) != NULL)
+				gs_app_add_kudo (app, GS_APP_KUDO_MY_LANGUAGE);
+		}
+
+		/* Set this under the FLAGS_REQUIRE_KUDOS flag because it’s
+		 * only useful in combination with KUDO_MY_LANGUAGE */
+		if (xb_node_query_text (component, "languages/lang", NULL) != NULL)
+			gs_app_set_has_translations (app, TRUE);
+
+		/* any keywords */
+		if (xb_node_query_text (component, "keywords/keyword", NULL) != NULL)
+			gs_app_add_kudo (app, GS_APP_KUDO_HAS_KEYWORDS);
+
+		/* HiDPI icon */
+		if (xb_node_query_text (component, "icon[@width='128']", NULL) != NULL)
+			gs_app_add_kudo (app, GS_APP_KUDO_HI_DPI_ICON);
+
+		/* was this application released recently */
+		if (gs_appstream_is_recent_release (component))
+			gs_app_add_kudo (app, GS_APP_KUDO_RECENT_RELEASE);
+
+		/* add a kudo to featured and popular apps */
+		if (xb_node_query_text (component, "kudos/kudo[text()='GnomeSoftware::popular']", NULL) != NULL)
+			gs_app_add_kudo (app, GS_APP_KUDO_FEATURED_RECOMMENDED);
+		if (xb_node_query_text (component, "categories/category[text()='Featured']", NULL) != NULL)
+			gs_app_add_kudo (app, GS_APP_KUDO_FEATURED_RECOMMENDED);
+	}
+
+	/* we have an origin in the XML */
+	if ((refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN) > 0 &&
+	    gs_app_get_origin_appstream (app) == NULL) {
+		g_autoptr(XbNode) parent = xb_node_get_parent (component);
+		if (parent != NULL) {
+			tmp = xb_node_get_attr (parent, "origin");
+			if (gs_appstream_origin_valid (tmp))
+				gs_app_set_origin_appstream (app, tmp);
+		}
+	}
+
+	/* is there any update information */
+	if ((refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_UPDATE_DETAILS) != 0 &&
+	    silo != NULL) {
+		if (!gs_appstream_refine_app_updates (app,
+						      silo,
+						      component,
+						      error))
+			return FALSE;
+	}
+
+	return TRUE;
+}
+
+typedef struct {
+	AsSearchTokenMatch	 match_value;
+	XbQuery			*query;
+} GsAppstreamSearchHelper;
+
+static void
+gs_appstream_search_helper_free (GsAppstreamSearchHelper *helper)
+{
+	g_object_unref (helper->query);
+	g_free (helper);
+}
+
+static guint16
+gs_appstream_silo_search_component2 (GPtrArray *array, XbNode *component, const gchar *search)
+{
+	guint16 match_value = 0;
+
+	/* do searches */
+	for (guint i = 0; i < array->len; i++) {
+		g_autoptr(GPtrArray) n = NULL;
+		GsAppstreamSearchHelper *helper = g_ptr_array_index (array, i);
+#if LIBXMLB_CHECK_VERSION(0, 3, 0)
+		g_auto(XbQueryContext) context = XB_QUERY_CONTEXT_INIT ();
+		xb_value_bindings_bind_str (xb_query_context_get_bindings (&context), 0, search, NULL);
+		n = xb_node_query_with_context (component, helper->query, &context, NULL);
+#else
+		xb_query_bind_str (helper->query, 0, search, NULL);
+		n = xb_node_query_full (component, helper->query, NULL);
+#endif
+		if (n != NULL)
+			match_value |= helper->match_value;
+	}
+	return match_value;
+}
+
+static guint16
+gs_appstream_silo_search_component (GPtrArray *array, XbNode *component, const gchar * const *search)
+{
+	guint16 matches_sum = 0;
+
+	/* do *all* search keywords match */
+	for (guint i = 0; search[i] != NULL; i++) {
+		guint tmp = gs_appstream_silo_search_component2 (array, component, search[i]);
+		if (tmp == 0)
+			return 0;
+		matches_sum |= tmp;
+	}
+	return matches_sum;
+}
+
+typedef struct {
+	AsSearchTokenMatch	match_value;
+	const gchar		*xpath;
+} Query;
+
+static gboolean
+gs_appstream_do_search (GsPlugin *plugin,
+			XbSilo *silo,
+			const gchar * const *values,
+			const Query queries[],
+			GsAppList *list,
+			GCancellable *cancellable,
+			GError **error)
+{
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GPtrArray) array = g_ptr_array_new_with_free_func ((GDestroyNotify) gs_appstream_search_helper_free);
+	g_autoptr(GPtrArray) components = NULL;
+	g_autoptr(GTimer) timer = g_timer_new ();
+
+	g_return_val_if_fail (GS_IS_PLUGIN (plugin), FALSE);
+	g_return_val_if_fail (XB_IS_SILO (silo), FALSE);
+	g_return_val_if_fail (values != NULL, FALSE);
+	g_return_val_if_fail (GS_IS_APP_LIST (list), FALSE);
+
+	/* add some weighted queries */
+	for (guint i = 0; queries[i].xpath != NULL; i++) {
+		g_autoptr(GError) error_query = NULL;
+		g_autoptr(XbQuery) query = xb_query_new (silo, queries[i].xpath, &error_query);
+		if (query != NULL) {
+			GsAppstreamSearchHelper *helper = g_new0 (GsAppstreamSearchHelper, 1);
+			helper->match_value = queries[i].match_value;
+			helper->query = g_steal_pointer (&query);
+			g_ptr_array_add (array, helper);
+		} else {
+			g_debug ("ignoring: %s", error_query->message);
+		}
+	}
+
+	/* get all components */
+	components = xb_silo_query (silo, "components/component", 0, &error_local);
+	if (components == NULL) {
+		if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+			return TRUE;
+		g_propagate_error (error, g_steal_pointer (&error_local));
+		return FALSE;
+	}
+	for (guint i = 0; i < components->len; i++) {
+		XbNode *component = g_ptr_array_index (components, i);
+		guint16 match_value = gs_appstream_silo_search_component (array, component, values);
+		if (match_value != 0) {
+			g_autoptr(GsApp) app = gs_appstream_create_app (plugin, silo, component, error);
+			if (app == NULL)
+				return FALSE;
+			if (gs_app_has_quirk (app, GS_APP_QUIRK_IS_WILDCARD)) {
+				g_debug ("not returning wildcard %s",
+					 gs_app_get_unique_id (app));
+				continue;
+			}
+			g_debug ("add %s", gs_app_get_unique_id (app));
+
+			/* The match value is used for prioritising results.
+			 * Drop the ID token from it as it’s the highest
+			 * numeric value but isn’t visible to the user in the
+			 * UI, which leads to confusing results ordering. */
+			gs_app_set_match_value (app, match_value & (~AS_SEARCH_TOKEN_MATCH_ID));
+			gs_app_list_add (list, app);
+
+			if (gs_app_get_kind (app) == AS_COMPONENT_KIND_ADDON) {
+				g_autoptr(GPtrArray) extends = NULL;
+
+				/* add the parent app as a wildcard, to be refined later */
+				extends = xb_node_query (component, "extends", 0, NULL);
+				for (guint jj = 0; extends && jj < extends->len; jj++) {
+					XbNode *extend = g_ptr_array_index (extends, jj);
+					g_autoptr(GsApp) app2 = NULL;
+					const gchar *tmp;
+					app2 = gs_app_new (xb_node_get_text (extend));
+					gs_app_add_quirk (app2, GS_APP_QUIRK_IS_WILDCARD);
+					tmp = xb_node_query_attr (extend, "../..", "origin", NULL);
+					if (gs_appstream_origin_valid (tmp))
+						gs_app_set_origin_appstream (app2, tmp);
+					gs_app_list_add (list, app2);
+				}
+			}
+		}
+
+		if (g_cancellable_set_error_if_cancelled (cancellable, error))
+			return FALSE;
+	}
+	g_debug ("search took %fms", g_timer_elapsed (timer, NULL) * 1000);
+	return TRUE;
+}
+
+/* This tokenises and stems @values internally for comparison against the
+ * already-stemmed tokens in the libxmlb silo */
+gboolean
+gs_appstream_search (GsPlugin *plugin,
+		     XbSilo *silo,
+		     const gchar * const *values,
+		     GsAppList *list,
+		     GCancellable *cancellable,
+		     GError **error)
+{
+	const Query queries[] = {
+		{ AS_SEARCH_TOKEN_MATCH_MIMETYPE,	"mimetypes/mimetype[text()~=stem(?)]" },
+		{ AS_SEARCH_TOKEN_MATCH_PKGNAME,	"pkgname[text()~=stem(?)]" },
+		{ AS_SEARCH_TOKEN_MATCH_SUMMARY,	"summary[text()~=stem(?)]" },
+		{ AS_SEARCH_TOKEN_MATCH_NAME,	"name[text()~=stem(?)]" },
+		{ AS_SEARCH_TOKEN_MATCH_KEYWORD,	"keywords/keyword[text()~=stem(?)]" },
+		{ AS_SEARCH_TOKEN_MATCH_ID,	"id[text()~=stem(?)]" },
+		{ AS_SEARCH_TOKEN_MATCH_ID,	"launchable[text()~=stem(?)]" },
+		{ AS_SEARCH_TOKEN_MATCH_ORIGIN,	"../components[@origin~=stem(?)]" },
+		{ AS_SEARCH_TOKEN_MATCH_NONE,	NULL }
+	};
+
+	return gs_appstream_do_search (plugin, silo, values, queries, list, cancellable, error);
+}
+
+gboolean
+gs_appstream_search_developer_apps (GsPlugin *plugin,
+				    XbSilo *silo,
+				    const gchar * const *values,
+				    GsAppList *list,
+				    GCancellable *cancellable,
+				    GError **error)
+{
+	const Query queries[] = {
+		{ AS_SEARCH_TOKEN_MATCH_PKGNAME,	"developer_name[text()~=stem(?)]" },
+		{ AS_SEARCH_TOKEN_MATCH_SUMMARY,	"project_group[text()~=stem(?)]" },
+		{ AS_SEARCH_TOKEN_MATCH_NONE,		NULL }
+	};
+
+	return gs_appstream_do_search (plugin, silo, values, queries, list, cancellable, error);
+}
+
+gboolean
+gs_appstream_add_category_apps (GsPlugin *plugin,
+				XbSilo *silo,
+				GsCategory *category,
+				GsAppList *list,
+				GCancellable *cancellable,
+				GError **error)
+{
+	GPtrArray *desktop_groups;
+
+	g_return_val_if_fail (GS_IS_PLUGIN (plugin), FALSE);
+	g_return_val_if_fail (XB_IS_SILO (silo), FALSE);
+	g_return_val_if_fail (GS_IS_CATEGORY (category), FALSE);
+	g_return_val_if_fail (GS_IS_APP_LIST (list), FALSE);
+
+	desktop_groups = gs_category_get_desktop_groups (category);
+	if (desktop_groups->len == 0) {
+		g_warning ("no desktop_groups for %s", gs_category_get_id (category));
+		return TRUE;
+	}
+	for (guint j = 0; j < desktop_groups->len; j++) {
+		const gchar *desktop_group = g_ptr_array_index (desktop_groups, j);
+		g_autofree gchar *xpath = NULL;
+		g_auto(GStrv) split = g_strsplit (desktop_group, "::", -1);
+		g_autoptr(GPtrArray) components = NULL;
+		g_autoptr(GError) error_local = NULL;
+
+		/* generate query */
+		if (g_strv_length (split) == 1) {
+			xpath = g_strdup_printf ("components/component/categories/"
+						 "category[text()='%s']/../..",
+						 split[0]);
+		} else if (g_strv_length (split) == 2) {
+			xpath = g_strdup_printf ("components/component/categories/"
+						 "category[text()='%s']/../"
+						 "category[text()='%s']/../..",
+						 split[0], split[1]);
+		}
+		components = xb_silo_query (silo, xpath, 0, &error_local);
+		if (components == NULL) {
+			if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+				continue;
+			g_propagate_error (error, g_steal_pointer (&error_local));
+			return FALSE;
+		}
+
+		/* create app */
+		for (guint i = 0; i < components->len; i++) {
+			XbNode *component = g_ptr_array_index (components, i);
+			g_autoptr(GsApp) app = NULL;
+			const gchar *id = xb_node_query_text (component, "id", NULL);
+			if (id == NULL)
+				continue;
+			app = gs_app_new (id);
+			gs_app_set_metadata (app, "GnomeSoftware::Creator",
+					     gs_plugin_get_name (plugin));
+			gs_app_add_quirk (app, GS_APP_QUIRK_IS_WILDCARD);
+			gs_app_list_add (list, app);
+		}
+
+	}
+	return TRUE;
+}
+
+static guint
+gs_appstream_count_component_for_groups (XbSilo      *silo,
+                                         const gchar *desktop_group)
+{
+	guint limit = 10;
+	g_autofree gchar *xpath = NULL;
+	g_auto(GStrv) split = g_strsplit (desktop_group, "::", -1);
+	g_autoptr(GPtrArray) array = NULL;
+	g_autoptr(GError) error_local = NULL;
+
+	if (g_strv_length (split) == 1) { /* "all" group for a parent category */
+		xpath = g_strdup_printf ("components/component/categories/"
+					 "category[text()='%s']/../..",
+					 split[0]);
+	} else if (g_strv_length (split) == 2) {
+		xpath = g_strdup_printf ("components/component/categories/"
+					 "category[text()='%s']/../"
+					 "category[text()='%s']/../..",
+					 split[0], split[1]);
+	} else {
+		return 0;
+	}
+
+	array = xb_silo_query (silo, xpath, limit, &error_local);
+	if (array == NULL) {
+		if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+			return 0;
+		g_warning ("%s", error_local->message);
+		return 0;
+	}
+	return array->len;
+}
+
+/* we're not actually adding categories here, we're just setting the number of
+ * applications available in each category */
+gboolean
+gs_appstream_refine_category_sizes (XbSilo        *silo,
+                                    GPtrArray     *list,
+                                    GCancellable  *cancellable,
+                                    GError       **error)
+{
+	g_return_val_if_fail (XB_IS_SILO (silo), FALSE);
+	g_return_val_if_fail (list != NULL, FALSE);
+
+	for (guint j = 0; j < list->len; j++) {
+		GsCategory *parent = GS_CATEGORY (g_ptr_array_index (list, j));
+		GPtrArray *children = gs_category_get_children (parent);
+
+		for (guint i = 0; i < children->len; i++) {
+			GsCategory *cat = g_ptr_array_index (children, i);
+			GPtrArray *groups = gs_category_get_desktop_groups (cat);
+			for (guint k = 0; k < groups->len; k++) {
+				const gchar *group = g_ptr_array_index (groups, k);
+				guint cnt = gs_appstream_count_component_for_groups (silo, group);
+				if (cnt > 0) {
+					gs_category_increment_size (parent, cnt);
+					if (children->len > 1) {
+						/* Parent category has multiple groups, so increment
+						 * each group's size too */
+						gs_category_increment_size (cat, cnt);
+					}
+				}
+			}
+		}
+		continue;
+	}
+	return TRUE;
+}
+
+gboolean
+gs_appstream_add_installed (GsPlugin      *plugin,
+                            XbSilo        *silo,
+                            GsAppList     *list,
+                            GCancellable  *cancellable,
+                            GError       **error)
+{
+	g_autoptr(GPtrArray) components = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	g_return_val_if_fail (GS_IS_PLUGIN (plugin), FALSE);
+	g_return_val_if_fail (XB_IS_SILO (silo), FALSE);
+	g_return_val_if_fail (GS_IS_APP_LIST (list), FALSE);
+
+	/* get all installed appdata files (notice no 'components/' prefix...) */
+	components = xb_silo_query (silo, "component/description/..", 0, NULL);
+	if (components == NULL)
+		return TRUE;
+
+	for (guint i = 0; i < components->len; i++) {
+		XbNode *component = g_ptr_array_index (components, i);
+		g_autoptr(GsApp) app = gs_appstream_create_app (plugin, silo, component, error);
+		if (app == NULL)
+			return FALSE;
+
+		/* Can get cached GsApp, which has the state already updated */
+		if (gs_app_get_state (app) != GS_APP_STATE_UPDATABLE &&
+		    gs_app_get_state (app) != GS_APP_STATE_UPDATABLE_LIVE)
+			gs_app_set_state (app, GS_APP_STATE_INSTALLED);
+		gs_app_set_scope (app, AS_COMPONENT_SCOPE_SYSTEM);
+		gs_app_list_add (list, app);
+	}
+
+	return TRUE;
+}
+
+gboolean
+gs_appstream_add_popular (XbSilo *silo,
+			  GsAppList *list,
+			  GCancellable *cancellable,
+			  GError **error)
+{
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GPtrArray) array = NULL;
+
+	g_return_val_if_fail (XB_IS_SILO (silo), FALSE);
+	g_return_val_if_fail (GS_IS_APP_LIST (list), FALSE);
+
+	/* find out how many packages are in each category */
+	array = xb_silo_query (silo,
+			       "components/component/kudos/"
+			       "kudo[text()='GnomeSoftware::popular']/../..",
+			       0, &error_local);
+	if (array == NULL) {
+		if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+			return TRUE;
+		g_propagate_error (error, g_steal_pointer (&error_local));
+		return FALSE;
+	}
+	for (guint i = 0; i < array->len; i++) {
+		g_autoptr(GsApp) app = NULL;
+		XbNode *component = g_ptr_array_index (array, i);
+		const gchar *component_id = xb_node_query_text (component, "id", NULL);
+		if (component_id == NULL)
+			continue;
+		app = gs_app_new (component_id);
+		gs_app_add_quirk (app, GS_APP_QUIRK_IS_WILDCARD);
+		gs_app_list_add (list, app);
+	}
+	return TRUE;
+}
+
+gboolean
+gs_appstream_add_recent (GsPlugin *plugin,
+			 XbSilo *silo,
+			 GsAppList *list,
+			 guint64 age,
+			 GCancellable *cancellable,
+			 GError **error)
+{
+	guint64 now = (guint64) g_get_real_time () / G_USEC_PER_SEC;
+	g_autofree gchar *xpath = NULL;
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GPtrArray) array = NULL;
+
+	g_return_val_if_fail (GS_IS_PLUGIN (plugin), FALSE);
+	g_return_val_if_fail (XB_IS_SILO (silo), FALSE);
+	g_return_val_if_fail (GS_IS_APP_LIST (list), FALSE);
+
+	/* use predicate conditions to the max */
+	xpath = g_strdup_printf ("components/component/releases/"
+				 "release[@timestamp>%" G_GUINT64_FORMAT "]/../..",
+				 now - age);
+	array = xb_silo_query (silo, xpath, 0, &error_local);
+	if (array == NULL) {
+		if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+			return TRUE;
+		g_propagate_error (error, g_steal_pointer (&error_local));
+		return FALSE;
+	}
+	for (guint i = 0; i < array->len; i++) {
+		XbNode *component = g_ptr_array_index (array, i);
+		g_autoptr(GsApp) app = gs_appstream_create_app (plugin, silo, component, error);
+		guint64 timestamp;
+		if (app == NULL)
+			return FALSE;
+		/* set the release date */
+		timestamp = component_get_release_timestamp (component);
+		if (timestamp != G_MAXUINT64)
+			gs_app_set_release_date (app, timestamp);
+		gs_app_list_add (list, app);
+	}
+	return TRUE;
+}
+
+gboolean
+gs_appstream_add_alternates (XbSilo *silo,
+			     GsApp *app,
+			     GsAppList *list,
+			     GCancellable *cancellable,
+			     GError **error)
+{
+	GPtrArray *sources = gs_app_get_sources (app);
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GPtrArray) ids = NULL;
+	g_autoptr(GString) xpath = g_string_new (NULL);
+
+	g_return_val_if_fail (XB_IS_SILO (silo), FALSE);
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+	g_return_val_if_fail (GS_IS_APP_LIST (list), FALSE);
+
+	/* probably a package we know nothing about */
+	if (gs_app_get_id (app) == NULL)
+		return TRUE;
+
+	/* actual ID */
+	xb_string_append_union (xpath, "components/component/id[text()='%s']",
+				gs_app_get_id (app));
+
+	/* new ID -> old ID */
+	xb_string_append_union (xpath, "components/component/id[text()='%s']/../provides/id",
+				gs_app_get_id (app));
+
+	/* old ID -> new ID */
+	xb_string_append_union (xpath, "components/component/provides/id[text()='%s']/../../id",
+				gs_app_get_id (app));
+
+	/* find apps that use the same pkgname */
+	for (guint j = 0; j < sources->len; j++) {
+		const gchar *source = g_ptr_array_index (sources, j);
+		g_autofree gchar *source_safe = xb_string_escape (source);
+		xb_string_append_union (xpath,
+					"components/component/pkgname[text()='%s']/../id",
+					source_safe);
+	}
+
+	/* do a big query, and return all the unique results */
+	ids = xb_silo_query (silo, xpath->str, 0, &error_local);
+	if (ids == NULL) {
+		if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+			return TRUE;
+		g_propagate_error (error, g_steal_pointer (&error_local));
+		return FALSE;
+	}
+	for (guint i = 0; i < ids->len; i++) {
+		XbNode *n = g_ptr_array_index (ids, i);
+		g_autoptr(GsApp) app2 = NULL;
+		const gchar *tmp;
+		app2 = gs_app_new (xb_node_get_text (n));
+		gs_app_add_quirk (app2, GS_APP_QUIRK_IS_WILDCARD);
+
+		tmp = xb_node_query_attr (n, "../..", "origin", NULL);
+		if (gs_appstream_origin_valid (tmp))
+			gs_app_set_origin_appstream (app2, tmp);
+		gs_app_list_add (list, app2);
+	}
+	return TRUE;
+}
+
+static gboolean
+gs_appstream_add_featured_with_query (XbSilo *silo,
+				      const gchar *query,
+				      GsAppList *list,
+				      GCancellable *cancellable,
+				      GError **error)
+{
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GPtrArray) array = NULL;
+
+	g_return_val_if_fail (XB_IS_SILO (silo), FALSE);
+	g_return_val_if_fail (GS_IS_APP_LIST (list), FALSE);
+
+	/* find out how many packages are in each category */
+	array = xb_silo_query (silo, query, 0, &error_local);
+	if (array == NULL) {
+		if (g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+			return TRUE;
+		g_propagate_error (error, g_steal_pointer (&error_local));
+		return FALSE;
+	}
+	for (guint i = 0; i < array->len; i++) {
+		g_autoptr(GsApp) app = NULL;
+		XbNode *component = g_ptr_array_index (array, i);
+		const gchar *component_id = xb_node_query_text (component, "id", NULL);
+		if (component_id == NULL)
+			continue;
+		app = gs_app_new (component_id);
+		gs_app_add_quirk (app, GS_APP_QUIRK_IS_WILDCARD);
+		if (!gs_appstream_copy_metadata (app, component, error))
+			return FALSE;
+		gs_app_list_add (list, app);
+	}
+	return TRUE;
+}
+
+gboolean
+gs_appstream_add_featured (XbSilo *silo,
+			   GsAppList *list,
+			   GCancellable *cancellable,
+			   GError **error)
+{
+	const gchar *query = "components/component/custom/value[@key='GnomeSoftware::FeatureTile']/../..|"
+			     "components/component/custom/value[@key='GnomeSoftware::FeatureTile-css']/../..";
+	return gs_appstream_add_featured_with_query (silo, query, list, cancellable, error);
+}
+
+gboolean
+gs_appstream_add_deployment_featured (XbSilo *silo,
+				      const gchar * const *deployments,
+				      GsAppList *list,
+				      GCancellable *cancellable,
+				      GError **error)
+{
+	g_autoptr(GString) query = g_string_new (NULL);
+	g_return_val_if_fail (XB_IS_SILO (silo), FALSE);
+	g_return_val_if_fail (deployments != NULL, FALSE);
+	g_return_val_if_fail (GS_IS_APP_LIST (list), FALSE);
+	for (guint ii = 0; deployments[ii] != NULL; ii++) {
+		g_autofree gchar *escaped = xb_string_escape (deployments[ii]);
+		if (escaped != NULL && *escaped != '\0') {
+			xb_string_append_union (query,
+				"components/component/custom/value[@key='GnomeSoftware::DeploymentFeatured'][text()='%s']/../..",
+				escaped);
+		}
+	}
+	if (!query->len)
+		return TRUE;
+	return gs_appstream_add_featured_with_query (silo, query->str, list, cancellable, error);
+}
+
+gboolean
+gs_appstream_url_to_app (GsPlugin *plugin,
+			 XbSilo *silo,
+			 GsAppList *list,
+			 const gchar *url,
+			 GCancellable *cancellable,
+			 GError **error)
+{
+	g_autofree gchar *path = NULL;
+	g_autofree gchar *scheme = NULL;
+	g_autofree gchar *xpath = NULL;
+	g_autoptr(GPtrArray) components = NULL;
+
+	g_return_val_if_fail (GS_IS_PLUGIN (plugin), FALSE);
+	g_return_val_if_fail (XB_IS_SILO (silo), FALSE);
+	g_return_val_if_fail (GS_IS_APP_LIST (list), FALSE);
+	g_return_val_if_fail (url != NULL, FALSE);
+
+	/* not us */
+	scheme = gs_utils_get_url_scheme (url);
+	if (g_strcmp0 (scheme, "appstream") != 0)
+		return TRUE;
+
+	path = gs_utils_get_url_path (url);
+	xpath = g_strdup_printf ("components/component/id[text()='%s']/..", path);
+	components = xb_silo_query (silo, xpath, 0, NULL);
+	if (components == NULL)
+		return TRUE;
+
+	for (guint i = 0; i < components->len; i++) {
+		XbNode *component = g_ptr_array_index (components, i);
+		g_autoptr(GsApp) app = NULL;
+		app = gs_appstream_create_app (plugin, silo, component, error);
+		if (app == NULL)
+			return FALSE;
+		gs_app_set_scope (app, AS_COMPONENT_SCOPE_SYSTEM);
+		gs_app_list_add (list, app);
+	}
+
+	return TRUE;
+}
+
+void
+gs_appstream_component_add_keyword (XbBuilderNode *component, const gchar *str)
+{
+	g_autoptr(XbBuilderNode) keyword = NULL;
+	g_autoptr(XbBuilderNode) keywords = NULL;
+
+	g_return_if_fail (XB_IS_BUILDER_NODE (component));
+	g_return_if_fail (str != NULL);
+
+	/* create <keywords> if it does not already exist */
+	keywords = xb_builder_node_get_child (component, "keywords", NULL);
+	if (keywords == NULL)
+		keywords = xb_builder_node_insert (component, "keywords", NULL);
+
+	/* create <keyword>str</keyword> if it does not already exist */
+	keyword = xb_builder_node_get_child (keywords, "keyword", str);
+	if (keyword == NULL) {
+		keyword = xb_builder_node_insert (keywords, "keyword", NULL);
+		xb_builder_node_set_text (keyword, str, -1);
+	}
+}
+
+void
+gs_appstream_component_add_provide (XbBuilderNode *component, const gchar *str)
+{
+	g_autoptr(XbBuilderNode) provide = NULL;
+	g_autoptr(XbBuilderNode) provides = NULL;
+
+	g_return_if_fail (XB_IS_BUILDER_NODE (component));
+	g_return_if_fail (str != NULL);
+
+	/* create <provides> if it does not already exist */
+	provides = xb_builder_node_get_child (component, "provides", NULL);
+	if (provides == NULL)
+		provides = xb_builder_node_insert (component, "provides", NULL);
+
+	/* create <id>str</id> if it does not already exist */
+	provide = xb_builder_node_get_child (provides, "id", str);
+	if (provide == NULL) {
+		provide = xb_builder_node_insert (provides, "id", NULL);
+		xb_builder_node_set_text (provide, str, -1);
+	}
+}
+
+void
+gs_appstream_component_add_category (XbBuilderNode *component, const gchar *str)
+{
+	g_autoptr(XbBuilderNode) category = NULL;
+	g_autoptr(XbBuilderNode) categories = NULL;
+
+	g_return_if_fail (XB_IS_BUILDER_NODE (component));
+	g_return_if_fail (str != NULL);
+
+	/* create <categories> if it does not already exist */
+	categories = xb_builder_node_get_child (component, "categories", NULL);
+	if (categories == NULL)
+		categories = xb_builder_node_insert (component, "categories", NULL);
+
+	/* create <category>str</category> if it does not already exist */
+	category = xb_builder_node_get_child (categories, "category", str);
+	if (category == NULL) {
+		category = xb_builder_node_insert (categories, "category", NULL);
+		xb_builder_node_set_text (category, str, -1);
+	}
+}
+
+void
+gs_appstream_component_add_icon (XbBuilderNode *component, const gchar *str)
+{
+	g_autoptr(XbBuilderNode) icon = NULL;
+
+	g_return_if_fail (XB_IS_BUILDER_NODE (component));
+	g_return_if_fail (str != NULL);
+
+	/* create <icon>str</icon> if it does not already exist */
+	icon = xb_builder_node_get_child (component, "icon", NULL);
+	if (icon == NULL) {
+		icon = xb_builder_node_insert (component, "icon",
+					       "type", "stock",
+					       NULL);
+		xb_builder_node_set_text (icon, str, -1);
+	}
+}
+
+void
+gs_appstream_component_add_extra_info (XbBuilderNode *component)
+{
+	const gchar *kind;
+
+	g_return_if_fail (XB_IS_BUILDER_NODE (component));
+
+	kind = xb_builder_node_get_attr (component, "type");
+
+	/* add the gnome-software-specific 'Addon' group and ensure they
+	 * all have an icon set */
+	switch (as_component_kind_from_string (kind)) {
+	case AS_COMPONENT_KIND_WEB_APP:
+		gs_appstream_component_add_keyword (component, kind);
+		break;
+	case AS_COMPONENT_KIND_FONT:
+		gs_appstream_component_add_category (component, "Addon");
+		gs_appstream_component_add_category (component, "Font");
+		break;
+	case AS_COMPONENT_KIND_DRIVER:
+		gs_appstream_component_add_category (component, "Addon");
+		gs_appstream_component_add_category (component, "Driver");
+		gs_appstream_component_add_icon (component, "system-component-driver");
+		break;
+	case AS_COMPONENT_KIND_LOCALIZATION:
+		gs_appstream_component_add_category (component, "Addon");
+		gs_appstream_component_add_category (component, "Localization");
+		gs_appstream_component_add_icon (component, "system-component-language");
+		break;
+	case AS_COMPONENT_KIND_CODEC:
+		gs_appstream_component_add_category (component, "Addon");
+		gs_appstream_component_add_category (component, "Codec");
+		gs_appstream_component_add_icon (component, "system-component-codecs");
+		break;
+	case AS_COMPONENT_KIND_INPUT_METHOD:
+		gs_appstream_component_add_keyword (component, kind);
+		gs_appstream_component_add_category (component, "Addon");
+		gs_appstream_component_add_category (component, "InputSource");
+		gs_appstream_component_add_icon (component, "system-component-input-sources");
+		break;
+	case AS_COMPONENT_KIND_FIRMWARE:
+		gs_appstream_component_add_icon (component, "system-component-firmware");
+		break;
+	default:
+		break;
+	}
+}
+
+/* Resolve any media URIs which are actually relative
+ * paths against the media_baseurl property */
+void
+gs_appstream_component_fix_url (XbBuilderNode *component, const gchar *baseurl)
+{
+	const gchar *text;
+	g_autofree gchar *url = NULL;
+
+	g_return_if_fail (XB_IS_BUILDER_NODE (component));
+	g_return_if_fail (baseurl != NULL);
+
+	text = xb_builder_node_get_text (component);
+
+	if (text == NULL)
+		return;
+
+	if (g_str_has_prefix (text, "http:") ||
+	    g_str_has_prefix (text, "https:"))
+		return;
+
+	url = g_strconcat (baseurl, "/", text, NULL);
+	xb_builder_node_set_text (component, url , -1);
+}
diff --git a/lib/gs-appstream.h b/lib/gs-appstream.h
new file mode 100644
index 0000000..d0d6ea2
--- /dev/null
+++ b/lib/gs-appstream.h
@@ -0,0 +1,95 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2015-2017 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <gnome-software.h>
+#include <xmlb.h>
+
+G_BEGIN_DECLS
+
+GsApp		*gs_appstream_create_app		(GsPlugin	*plugin,
+							 XbSilo		*silo,
+							 XbNode		*component,
+							 GError		**error);
+gboolean	 gs_appstream_refine_app		(GsPlugin	*plugin,
+							 GsApp		*app,
+							 XbSilo		*silo,
+							 XbNode		*component,
+							 GsPluginRefineFlags flags,
+							 GError		**error);
+gboolean	 gs_appstream_search			(GsPlugin	*plugin,
+							 XbSilo		*silo,
+							 const gchar * const *values,
+							 GsAppList	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+gboolean	 gs_appstream_search_developer_apps	(GsPlugin	*plugin,
+							 XbSilo		*silo,
+							 const gchar * const *values,
+							 GsAppList	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+gboolean	 gs_appstream_refine_category_sizes	(XbSilo		*silo,
+							 GPtrArray	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+gboolean	 gs_appstream_add_category_apps		(GsPlugin	*plugin,
+							 XbSilo		*silo,
+							 GsCategory	*category,
+							 GsAppList	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+gboolean	 gs_appstream_add_installed		(GsPlugin	*plugin,
+							 XbSilo		*silo,
+							 GsAppList	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+gboolean	 gs_appstream_add_popular		(XbSilo		*silo,
+							 GsAppList	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+gboolean	 gs_appstream_add_featured		(XbSilo		*silo,
+							 GsAppList	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+gboolean	 gs_appstream_add_deployment_featured	(XbSilo		*silo,
+							 const gchar * const *deployments,
+							 GsAppList	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+gboolean	 gs_appstream_add_alternates		(XbSilo		*silo,
+							 GsApp		*app,
+							 GsAppList	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+gboolean	 gs_appstream_add_recent		(GsPlugin	*plugin,
+							 XbSilo		*silo,
+							 GsAppList	*list,
+							 guint64	 age,
+							 GCancellable	*cancellable,
+							 GError		**error);
+gboolean	gs_appstream_url_to_app			(GsPlugin	*plugin,
+							 XbSilo		*silo,
+							 GsAppList	*list,
+							 const gchar	*url,
+							 GCancellable	*cancellable,
+							 GError		**error);
+void		 gs_appstream_component_add_extra_info	(XbBuilderNode	*component);
+void		 gs_appstream_component_add_keyword	(XbBuilderNode	*component,
+							 const gchar	*str);
+void		 gs_appstream_component_add_category	(XbBuilderNode	*component,
+							 const gchar	*str);
+void		 gs_appstream_component_add_icon	(XbBuilderNode	*component,
+							 const gchar	*str);
+void		 gs_appstream_component_add_provide	(XbBuilderNode	*component,
+							 const gchar	*str);
+void		 gs_appstream_component_fix_url		(XbBuilderNode  *component,
+							 const gchar    *baseurl);
+
+G_END_DECLS
diff --git a/lib/gs-build-ident.h.in b/lib/gs-build-ident.h.in
new file mode 100644
index 0000000..92cd79a
--- /dev/null
+++ b/lib/gs-build-ident.h.in
@@ -0,0 +1,32 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Matthew Leeds <mwleeds@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+
+G_BEGIN_DECLS
+
+/**
+ * SECTION:gs-build-ident
+ * @title: Build Identifier
+ * @short_description: Identify a build by unique build identifier
+ *
+ * Since: 40
+ */
+
+/**
+ * GS_BUILD_IDENTIFIER:
+ *
+ * A string containing a tag that defines the version of Software that
+ * was built. Generally, this will be a small version tag plus some
+ * information to identify the git commit hash when applicable.
+ */
+#define GS_BUILD_IDENTIFIER "@VCS_TAG@"
+
+G_END_DECLS
diff --git a/lib/gs-category-manager.c b/lib/gs-category-manager.c
new file mode 100644
index 0000000..0e37264
--- /dev/null
+++ b/lib/gs-category-manager.c
@@ -0,0 +1,151 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-category-manager
+ * @short_description: A container to store #GsCategory instances in
+ *
+ * #GsCategoryManager is a container object which stores #GsCategory instances,
+ * so that they can be consistently reused by other code, without creating
+ * multiple #GsCategory instances for the same category ID.
+ *
+ * It is intended to be used as a singleton, and typically accessed by calling
+ * gs_plugin_loader_get_category_manager().
+ *
+ * Since: 40
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <glib-object.h>
+#include <glib/gi18n.h>
+
+#include "gs-category-manager.h"
+#include "gs-desktop-data.h"
+
+struct _GsCategoryManager
+{
+	GObject		 parent;
+
+	/* Array of #GsCategory instances corresponding to the entries in gs_desktop_get_data()
+	 * The +1 is for a NULL terminator */
+	GsCategory	*categories[GS_DESKTOP_DATA_N_ENTRIES + 1];
+};
+
+G_DEFINE_TYPE (GsCategoryManager, gs_category_manager, G_TYPE_OBJECT)
+
+static void
+gs_category_manager_dispose (GObject *object)
+{
+	GsCategoryManager *self = GS_CATEGORY_MANAGER (object);
+
+	for (gsize i = 0; i < G_N_ELEMENTS (self->categories); i++)
+		g_clear_object (&self->categories[i]);
+
+	G_OBJECT_CLASS (gs_category_manager_parent_class)->dispose (object);
+}
+
+static void
+gs_category_manager_class_init (GsCategoryManagerClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+	object_class->dispose = gs_category_manager_dispose;
+}
+
+static void
+gs_category_manager_init (GsCategoryManager *self)
+{
+	const GsDesktopData *msdata;
+
+	/* Set up the category data, and check our expectations about the length
+	 * of gs_desktop_get_data() match reality. */
+	msdata = gs_desktop_get_data ();
+	for (gsize i = 0; msdata[i].id != NULL; i++) {
+		g_assert (i < G_N_ELEMENTS (self->categories) - 1);
+		self->categories[i] = gs_category_new_for_desktop_data (&msdata[i]);
+	}
+
+	g_assert (self->categories[G_N_ELEMENTS (self->categories) - 2] != NULL);
+	g_assert (self->categories[G_N_ELEMENTS (self->categories) - 1] == NULL);
+}
+
+/**
+ * gs_category_manager_new:
+ *
+ * Create a new #GsCategoryManager. It will contain all the categories, but
+ * their sizes will not be set until gs_category_increment_size() is called
+ * on them.
+ *
+ * Returns: (transfer full): a new #GsCategoryManager
+ * Since: 40
+ */
+GsCategoryManager *
+gs_category_manager_new (void)
+{
+	return g_object_new (GS_TYPE_CATEGORY_MANAGER, NULL);
+}
+
+/**
+ * gs_category_manager_lookup:
+ * @self: a #GsCategoryManager
+ * @id: ID of the category to look up
+ *
+ * Look up a category by its ID. If the category is not found, %NULL is
+ * returned.
+ *
+ * Returns: (transfer full) (nullable): the #GsCategory, or %NULL
+ * Since: 40
+ */
+GsCategory *
+gs_category_manager_lookup (GsCategoryManager *self,
+                            const gchar       *id)
+{
+	g_return_val_if_fail (GS_IS_CATEGORY_MANAGER (self), NULL);
+	g_return_val_if_fail (id != NULL && *id != '\0', NULL);
+
+	/* There are only on the order of 10 categories, so this is quick */
+	for (gsize i = 0; i < G_N_ELEMENTS (self->categories) - 1; i++) {
+		if (g_str_equal (gs_category_get_id (self->categories[i]), id))
+			return g_object_ref (self->categories[i]);
+	}
+
+	return NULL;
+}
+
+/**
+ * gs_category_manager_get_categories:
+ * @self: a #GsCategoryManager
+ * @out_n_categories: (optional) (out caller-allocates): return location for
+ *     the number of categories in the return value, or %NULL to ignore
+ *
+ * Get the full list of categories from the category manager. The returned array
+ * is %NULL terminated and guaranteed to be non-%NULL (although it may be
+ * empty).
+ *
+ * If @out_n_categories is provided, it will be set to the number of #GsCategory
+ * objects in the return value, not including the %NULL terminator.
+ *
+ * Returns: (array length=out_n_categories) (transfer none) (not nullable): the
+ *     categories; do not free this memory
+ * Since: 40
+ */
+GsCategory * const *
+gs_category_manager_get_categories (GsCategoryManager *self,
+                                    gsize             *out_n_categories)
+{
+	g_return_val_if_fail (GS_IS_CATEGORY_MANAGER (self), NULL);
+
+	if (out_n_categories != NULL)
+		*out_n_categories = G_N_ELEMENTS (self->categories) - 1;
+
+	return self->categories;
+}
diff --git a/lib/gs-category-manager.h b/lib/gs-category-manager.h
new file mode 100644
index 0000000..8e85fa3
--- /dev/null
+++ b/lib/gs-category-manager.h
@@ -0,0 +1,32 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <glib-object.h>
+
+#include "gs-category.h"
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_CATEGORY_MANAGER (gs_category_manager_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsCategoryManager, gs_category_manager, GS, CATEGORY_MANAGER, GObject)
+
+GsCategoryManager	*gs_category_manager_new	(void);
+
+GsCategory		*gs_category_manager_lookup	(GsCategoryManager	*self,
+							 const gchar		*id);
+
+GsCategory * const	*gs_category_manager_get_categories (GsCategoryManager	*self,
+							      gsize		*out_n_categories);
+
+G_END_DECLS
diff --git a/lib/gs-category-private.h b/lib/gs-category-private.h
new file mode 100644
index 0000000..1c9c292
--- /dev/null
+++ b/lib/gs-category-private.h
@@ -0,0 +1,21 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2013-2016 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2013 Matthias Clasen <mclasen@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include "gs-category.h"
+
+G_BEGIN_DECLS
+
+void		 gs_category_sort_children	(GsCategory	*category);
+void		 gs_category_set_size		(GsCategory	*category,
+						 guint		 size);
+gchar		*gs_category_to_string		(GsCategory	*category);
+
+G_END_DECLS
diff --git a/lib/gs-category.c b/lib/gs-category.c
new file mode 100644
index 0000000..befc167
--- /dev/null
+++ b/lib/gs-category.c
@@ -0,0 +1,724 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2013-2016 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2013 Matthias Clasen <mclasen@redhat.com>
+ * Copyright (C) 2015 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-category
+ * @short_description: An category that contains applications
+ *
+ * This object provides functionality that allows a plugin to create
+ * a tree structure of categories that each contain #GsApp's.
+ */
+
+#include "config.h"
+
+#include <glib/gi18n.h>
+
+#include "gs-category-private.h"
+#include "gs-desktop-data.h"
+
+struct _GsCategory
+{
+	GObject		 parent_instance;
+
+	const GsDesktopData	*desktop_data;  /* NULL for subcategories */
+	const GsDesktopMap	*desktop_map;  /* NULL for parent categories */
+
+	GPtrArray	*desktop_groups;  /* potentially NULL if empty */
+	GsCategory	*parent;
+	guint		 size;  /* (atomic) */
+	GPtrArray	*children;  /* potentially NULL if empty */
+};
+
+G_DEFINE_TYPE (GsCategory, gs_category, G_TYPE_OBJECT)
+
+typedef enum {
+	PROP_ID = 1,
+	PROP_NAME,
+	PROP_ICON_NAME,
+	PROP_SCORE,
+	PROP_PARENT,
+	PROP_SIZE,
+} GsCategoryProperty;
+
+static GParamSpec *obj_props[PROP_SIZE + 1] = { NULL, };
+
+/**
+ * gs_category_to_string:
+ * @category: a #GsCategory
+ *
+ * Returns a string representation of the category
+ *
+ * Returns: a string
+ *
+ * Since: 3.22
+ **/
+gchar *
+gs_category_to_string (GsCategory *category)
+{
+	guint i;
+	GString *str = g_string_new (NULL);
+	g_string_append_printf (str, "GsCategory[%p]:\n", category);
+	g_string_append_printf (str, "  id: %s\n",
+				gs_category_get_id (category));
+	if (gs_category_get_name (category) != NULL) {
+		g_string_append_printf (str, "  name: %s\n",
+					gs_category_get_name (category));
+	}
+	if (gs_category_get_icon_name (category) != NULL) {
+		g_string_append_printf (str, "  icon-name: %s\n",
+					gs_category_get_icon_name (category));
+	}
+	g_string_append_printf (str, "  size: %u\n",
+				gs_category_get_size (category));
+	g_string_append_printf (str, "  desktop-groups: %u\n",
+				(category->desktop_groups != NULL) ? category->desktop_groups->len : 0);
+	if (category->parent != NULL) {
+		g_string_append_printf (str, "  parent: %s\n",
+					gs_category_get_id (category->parent));
+	}
+	g_string_append_printf (str, "  score: %i\n", gs_category_get_score (category));
+	if (category->children == NULL || category->children->len == 0) {
+		g_string_append_printf (str, "  children: %u\n", 0u);
+	} else {
+		g_string_append_printf (str, "  children: %u\n", category->children->len);
+		for (i = 0; i < category->children->len; i++) {
+			GsCategory *child = g_ptr_array_index (category->children, i);
+			g_string_append_printf (str, "  - %s\n",
+						gs_category_get_id (child));
+		}
+	}
+	return g_string_free (str, FALSE);
+}
+
+/**
+ * gs_category_get_size:
+ * @category: a #GsCategory
+ *
+ * Returns how many applications the category could contain.
+ *
+ * NOTE: This may over-estimate the number if duplicate applications are
+ * filtered or core applications are not shown.
+ *
+ * Returns: the number of apps in the category
+ *
+ * Since: 3.22
+ **/
+guint
+gs_category_get_size (GsCategory *category)
+{
+	g_return_val_if_fail (GS_IS_CATEGORY (category), 0);
+
+	/* The ‘all’ subcategory is a bit special. */
+	if (category->parent != NULL && g_str_equal (gs_category_get_id (category), "all"))
+		return gs_category_get_size (category->parent);
+
+	return g_atomic_int_get (&category->size);
+}
+
+/**
+ * gs_category_set_size:
+ * @category: a #GsCategory
+ * @size: the number of applications
+ *
+ * Sets the number of applications in the category.
+ * Most plugins do not need to call this function.
+ *
+ * Since: 3.22
+ **/
+void
+gs_category_set_size (GsCategory *category, guint size)
+{
+	g_return_if_fail (GS_IS_CATEGORY (category));
+
+	g_atomic_int_set (&category->size, size);
+	g_object_notify_by_pspec (G_OBJECT (category), obj_props[PROP_SIZE]);
+}
+
+/**
+ * gs_category_increment_size:
+ * @category: a #GsCategory
+ * @value: how many to add
+ *
+ * Adds @value to the size count.
+ *
+ * Since: 3.22
+ **/
+void
+gs_category_increment_size (GsCategory *category,
+			    guint value)
+{
+	g_return_if_fail (GS_IS_CATEGORY (category));
+
+	g_atomic_int_add (&category->size, value);
+	if (value != 0)
+		g_object_notify_by_pspec (G_OBJECT (category), obj_props[PROP_SIZE]);
+}
+
+/**
+ * gs_category_get_id:
+ * @category: a #GsCategory
+ *
+ * Gets the category ID.
+ *
+ * Returns: the string, e.g. "other"
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_category_get_id (GsCategory *category)
+{
+	g_return_val_if_fail (GS_IS_CATEGORY (category), NULL);
+
+	if (category->desktop_data != NULL)
+		return category->desktop_data->id;
+	else if (category->desktop_map != NULL)
+		return category->desktop_map->id;
+	g_assert_not_reached ();
+}
+
+/**
+ * gs_category_get_name:
+ * @category: a #GsCategory
+ *
+ * Gets the category name.
+ *
+ * Returns: the string, or %NULL
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_category_get_name (GsCategory *category)
+{
+	const gchar *category_id;
+
+	g_return_val_if_fail (GS_IS_CATEGORY (category), NULL);
+
+	category_id = gs_category_get_id (category);
+
+	/* special case, we don't want translations in the plugins */
+	if (g_strcmp0 (category_id, "other") == 0) {
+		/* TRANSLATORS: this is where all applications that don't
+		 * fit in other groups are put */
+		return _("Other");
+	}
+	if (g_strcmp0 (category_id, "all") == 0) {
+		/* TRANSLATORS: this is a subcategory matching all the
+		 * different apps in the parent category, e.g. "Games" */
+		return C_("Category", "All");
+	}
+	if (g_strcmp0 (category_id, "featured") == 0) {
+		/* TRANSLATORS: this is a subcategory of featured apps */
+		return _("Featured");
+	}
+
+	/* normal case */
+	if (category->desktop_data != NULL) {
+		return gettext (category->desktop_data->name);
+	} else if (category->desktop_map != NULL) {
+		g_autofree gchar *msgctxt = g_strdup_printf ("Menu of %s", category->parent->desktop_data->name);
+		return g_dpgettext2 (GETTEXT_PACKAGE, msgctxt, category->desktop_map->name);
+	}
+
+	g_assert_not_reached ();
+}
+
+/**
+ * gs_category_get_icon_name:
+ * @category: a #GsCategory
+ *
+ * Gets the category icon name.
+ *
+ * Returns: the string, or %NULL
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_category_get_icon_name (GsCategory *category)
+{
+	const gchar *category_id;
+
+	g_return_val_if_fail (GS_IS_CATEGORY (category), NULL);
+
+	category_id = gs_category_get_id (category);
+
+	/* special case */
+	if (g_strcmp0 (category_id, "other") == 0)
+		return "emblem-system-symbolic";
+	if (g_strcmp0 (category_id, "all") == 0)
+		return "emblem-default-symbolic";
+	if (g_strcmp0 (category_id, "featured") == 0)
+		return "emblem-favorite-symbolic";
+
+	if (category->desktop_data != NULL)
+		return category->desktop_data->icon;
+	else
+		return NULL;
+}
+
+/**
+ * gs_category_get_score:
+ * @category: a #GsCategory
+ *
+ * Gets if the category score.
+ * Important categories may be shown before other categories, or tagged in a
+ * different way, for example with color or in a different section.
+ *
+ * Returns: the string, or %NULL
+ *
+ * Since: 3.22
+ **/
+gint
+gs_category_get_score (GsCategory *category)
+{
+	g_return_val_if_fail (GS_IS_CATEGORY (category), FALSE);
+
+	if (category->desktop_data != NULL)
+		return category->desktop_data->score;
+	else
+		return 0;
+}
+
+/**
+ * gs_category_get_desktop_groups:
+ * @category: a #GsCategory
+ *
+ * Gets the list of AppStream groups for the category.
+ *
+ * Returns: (element-type utf8) (transfer none): An array
+ *
+ * Since: 3.22
+ **/
+GPtrArray *
+gs_category_get_desktop_groups (GsCategory *category)
+{
+	g_return_val_if_fail (GS_IS_CATEGORY (category), NULL);
+
+	if (category->desktop_groups == NULL)
+		category->desktop_groups = g_ptr_array_new_with_free_func (g_free);
+
+	return category->desktop_groups;
+}
+
+/**
+ * gs_category_has_desktop_group:
+ * @category: a #GsCategory
+ * @desktop_group: a group of categories found in AppStream, e.g. "AudioVisual::Player"
+ *
+ * Finds out if the category has the specific AppStream desktop group.
+ *
+ * Returns: %TRUE if found, %FALSE otherwise
+ *
+ * Since: 3.22
+ **/
+gboolean
+gs_category_has_desktop_group (GsCategory *category, const gchar *desktop_group)
+{
+	guint i;
+
+	g_return_val_if_fail (GS_IS_CATEGORY (category), FALSE);
+	g_return_val_if_fail (desktop_group != NULL, FALSE);
+
+	if (category->desktop_groups == NULL)
+		return FALSE;
+
+	for (i = 0; i < category->desktop_groups->len; i++) {
+		const gchar *tmp = g_ptr_array_index (category->desktop_groups, i);
+		if (g_strcmp0 (tmp, desktop_group) == 0)
+			return TRUE;
+	}
+	return FALSE;
+}
+
+/*
+ * gs_category_add_desktop_group:
+ * @category: a #GsCategory
+ * @desktop_group: a group of categories found in AppStream, e.g. "AudioVisual::Player"
+ *
+ * Adds a desktop group to the category.
+ * A desktop group is a set of category strings that all must exist.
+ *
+ * Since: 3.22
+ */
+static void
+gs_category_add_desktop_group (GsCategory *category, const gchar *desktop_group)
+{
+	g_return_if_fail (GS_IS_CATEGORY (category));
+	g_return_if_fail (desktop_group != NULL);
+
+	/* add if not already found, and lazily create the groups array
+	 * (since it’s only needed in child categories) */
+	if (gs_category_has_desktop_group (category, desktop_group))
+		return;
+	if (category->desktop_groups == NULL)
+		category->desktop_groups = g_ptr_array_new_with_free_func (g_free);
+	g_ptr_array_add (category->desktop_groups, g_strdup (desktop_group));
+}
+
+/**
+ * gs_category_find_child:
+ * @category: a #GsCategory
+ * @id: a category ID, e.g. "other"
+ *
+ * Find a child category with a specific ID.
+ *
+ * Returns: (transfer none): the #GsCategory, or %NULL
+ *
+ * Since: 3.22
+ **/
+GsCategory *
+gs_category_find_child (GsCategory *category, const gchar *id)
+{
+	GsCategory *tmp;
+	guint i;
+
+	if (category->children == NULL)
+		return NULL;
+
+	/* find the subcategory */
+	for (i = 0; i < category->children->len; i++) {
+		tmp = GS_CATEGORY (g_ptr_array_index (category->children, i));
+		if (g_strcmp0 (id, gs_category_get_id (tmp)) == 0)
+			return tmp;
+	}
+	return NULL;
+}
+
+/**
+ * gs_category_get_parent:
+ * @category: a #GsCategory
+ *
+ * Gets the parent category.
+ *
+ * Returns: the #GsCategory or %NULL
+ *
+ * Since: 3.22
+ **/
+GsCategory *
+gs_category_get_parent (GsCategory *category)
+{
+	g_return_val_if_fail (GS_IS_CATEGORY (category), NULL);
+	return category->parent;
+}
+
+/**
+ * gs_category_get_children:
+ * @category: a #GsCategory
+ *
+ * Gets the list if children for a category.
+ *
+ * Return value: (element-type GsApp) (transfer none): A list of children
+ *
+ * Since: 3.22
+ **/
+GPtrArray *
+gs_category_get_children (GsCategory *category)
+{
+	g_return_val_if_fail (GS_IS_CATEGORY (category), NULL);
+
+	if (category->children == NULL)
+		category->children = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);
+
+	return category->children;
+}
+
+/*
+ * gs_category_add_child:
+ * @category: a #GsCategory
+ * @subcategory: a #GsCategory
+ *
+ * Adds a child category to a parent category.
+ *
+ * Since: 3.22
+ */
+static void
+gs_category_add_child (GsCategory *category, GsCategory *subcategory)
+{
+	g_return_if_fail (GS_IS_CATEGORY (category));
+	g_return_if_fail (GS_IS_CATEGORY (subcategory));
+
+	/* lazily create the array to save memory in subcategories, which don’t
+	 * recursively have children */
+	if (category->children == NULL)
+		category->children = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);
+
+	/* FIXME: do we need this? */
+	subcategory->parent = category;
+	g_object_add_weak_pointer (G_OBJECT (subcategory->parent),
+				   (gpointer *) &subcategory->parent);
+
+	g_ptr_array_add (category->children,
+			 g_object_ref (subcategory));
+}
+
+static gchar *
+gs_category_get_sort_key (GsCategory *category)
+{
+	guint sort_order = 5;
+	if (g_strcmp0 (gs_category_get_id (category), "featured") == 0)
+		sort_order = 0;
+	else if (g_strcmp0 (gs_category_get_id (category), "all") == 0)
+		sort_order = 2;
+	else if (g_strcmp0 (gs_category_get_id (category), "other") == 0)
+		sort_order = 9;
+	return g_strdup_printf ("%u:%s",
+				sort_order,
+				gs_category_get_name (category));
+}
+
+static gint
+gs_category_sort_children_cb (gconstpointer a, gconstpointer b)
+{
+	GsCategory *ca = GS_CATEGORY (*(GsCategory **) a);
+	GsCategory *cb = GS_CATEGORY (*(GsCategory **) b);
+	g_autofree gchar *id_a = gs_category_get_sort_key (ca);
+	g_autofree gchar *id_b = gs_category_get_sort_key (cb);
+	return g_strcmp0 (id_a, id_b);
+}
+
+/**
+ * gs_category_sort_children:
+ * @category: a #GsCategory
+ *
+ * Sorts the list of children.
+ *
+ * Since: 3.22
+ **/
+void
+gs_category_sort_children (GsCategory *category)
+{
+	if (category->children == NULL)
+		return;
+
+	g_ptr_array_sort (category->children,
+			  gs_category_sort_children_cb);
+}
+
+static void
+gs_category_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
+{
+	GsCategory *self = GS_CATEGORY (object);
+
+	switch ((GsCategoryProperty) prop_id) {
+	case PROP_ID:
+		g_value_set_string (value, gs_category_get_id (self));
+		break;
+	case PROP_NAME:
+		g_value_set_string (value, gs_category_get_name (self));
+		break;
+	case PROP_ICON_NAME:
+		g_value_set_string (value, gs_category_get_icon_name (self));
+		break;
+	case PROP_SCORE:
+		g_value_set_int (value, gs_category_get_score (self));
+		break;
+	case PROP_PARENT:
+		g_value_set_object (value, self->parent);
+		break;
+	case PROP_SIZE:
+		g_value_set_uint (value, gs_category_get_size (self));
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_category_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
+{
+	GsCategory *self = GS_CATEGORY (object);
+
+	switch ((GsCategoryProperty) prop_id) {
+	case PROP_ID:
+	case PROP_NAME:
+	case PROP_ICON_NAME:
+	case PROP_SCORE:
+	case PROP_PARENT:
+		/* Read only */
+		g_assert_not_reached ();
+		break;
+	case PROP_SIZE:
+		gs_category_set_size (self, g_value_get_uint (value));
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_category_finalize (GObject *object)
+{
+	GsCategory *category = GS_CATEGORY (object);
+
+	if (category->parent != NULL)
+		g_object_remove_weak_pointer (G_OBJECT (category->parent),
+		                              (gpointer *) &category->parent);
+	g_clear_pointer (&category->children, g_ptr_array_unref);
+	g_clear_pointer (&category->desktop_groups, g_ptr_array_unref);
+
+	G_OBJECT_CLASS (gs_category_parent_class)->finalize (object);
+}
+
+static void
+gs_category_class_init (GsCategoryClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+	object_class->get_property = gs_category_get_property;
+	object_class->set_property = gs_category_set_property;
+	object_class->finalize = gs_category_finalize;
+
+	/**
+	 * GsCategory:id:
+	 *
+	 * A machine readable identifier for the category. Must be non-empty
+	 * and in a valid format to be a
+	 * [desktop category ID](https://specifications.freedesktop.org/menu-spec/latest/).
+	 *
+	 * Since: 40
+	 */
+	obj_props[PROP_ID] =
+		g_param_spec_string ("id", NULL, NULL,
+				     NULL,
+				     G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsCategory:name:
+	 *
+	 * Human readable name for the category.
+	 *
+	 * Since: 40
+	 */
+	obj_props[PROP_NAME] =
+		g_param_spec_string ("name", NULL, NULL,
+				     NULL,
+				     G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsCategory:icon-name: (nullable)
+	 *
+	 * Name of the icon to use for the category, or %NULL if none is set.
+	 *
+	 * Since: 40
+	 */
+	obj_props[PROP_ICON_NAME] =
+		g_param_spec_string ("icon-name", NULL, NULL,
+				     NULL,
+				     G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsCategory:score:
+	 *
+	 * Score for sorting the category. Lower numeric values indicate more
+	 * important categories.
+	 *
+	 * Since: 40
+	 */
+	obj_props[PROP_SCORE] =
+		g_param_spec_int ("score", NULL, NULL,
+				  G_MININT, G_MAXINT, 0,
+				  G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsCategory:parent: (nullable)
+	 *
+	 * The parent #GsCategory, or %NULL if this category is at the top
+	 * level.
+	 *
+	 * Since: 40
+	 */
+	obj_props[PROP_PARENT] =
+		g_param_spec_object ("parent", NULL, NULL,
+				     GS_TYPE_CATEGORY,
+				     G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
+
+	/**
+	 * GsCategory:size:
+	 *
+	 * Number of apps in this category, including apps in its subcategories.
+	 *
+	 * This has to be initialised externally to the #GsCategory by calling
+	 * gs_category_increment_size().
+	 *
+	 * Since: 40
+	 */
+	obj_props[PROP_SIZE] =
+		g_param_spec_uint ("size", NULL, NULL,
+				   0, G_MAXUINT, 0,
+				   G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	g_object_class_install_properties (object_class, G_N_ELEMENTS (obj_props), obj_props);
+}
+
+static void
+gs_category_init (GsCategory *category)
+{
+}
+
+/**
+ * gs_category_new_for_desktop_data:
+ * @data: data for the category, which must be static and constant
+ *
+ * Create a new #GsCategory instance which wraps the desktop category
+ * information in @data. Where possible, the static data will be reused, so
+ * @data must be static and constant across the lifetime of the process.
+ *
+ * Returns: (transfer full): a new #GsCategory wrapping @data
+ * Since: 40
+ */
+GsCategory *
+gs_category_new_for_desktop_data (const GsDesktopData *data)
+{
+	g_autoptr(GsCategory) category = NULL;
+	GsCategory *subcategory_all = NULL;
+
+	/* parent category */
+	category = g_object_new (GS_TYPE_CATEGORY, NULL);
+	category->desktop_data = data;
+
+	/* add subcategories */
+	for (gsize j = 0; data->mapping[j].id != NULL; j++) {
+		const GsDesktopMap *map = &data->mapping[j];
+		g_autoptr(GsCategory) sub = g_object_new (GS_TYPE_CATEGORY, NULL);
+		sub->desktop_map = map;
+		for (gsize k = 0; map->fdo_cats[k] != NULL; k++)
+			gs_category_add_desktop_group (sub, map->fdo_cats[k]);
+		gs_category_add_child (category, sub);
+
+		if (g_str_equal (map->id, "all"))
+			subcategory_all = sub;
+	}
+
+	/* set up the ‘all’ subcategory specially, adding all the desktop groups
+	 * from all other child categories to it */
+	if (subcategory_all != NULL) {
+		g_assert (category->children != NULL);
+
+		for (guint i = 0; i < category->children->len; i++) {
+			GPtrArray *desktop_groups;
+			GsCategory *child;
+
+			/* ignore the all category */
+			child = g_ptr_array_index (category->children, i);
+			if (child == subcategory_all)
+				continue;
+
+			/* add all desktop groups */
+			desktop_groups = gs_category_get_desktop_groups (child);
+			for (guint j = 0; j < desktop_groups->len; j++) {
+				const gchar *tmp = g_ptr_array_index (desktop_groups, j);
+				gs_category_add_desktop_group (subcategory_all, tmp);
+			}
+		}
+	}
+
+	return g_steal_pointer (&category);
+}
diff --git a/lib/gs-category.h b/lib/gs-category.h
new file mode 100644
index 0000000..1e82591
--- /dev/null
+++ b/lib/gs-category.h
@@ -0,0 +1,45 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2013-2016 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2013 Matthias Clasen <mclasen@redhat.com>
+ * Copyright (C) 2015 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <glib-object.h>
+
+#include "gs-desktop-data.h"
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_CATEGORY (gs_category_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsCategory, gs_category, GS, CATEGORY, GObject)
+
+GsCategory	*gs_category_new_for_desktop_data	(const GsDesktopData	*data);
+
+const gchar	*gs_category_get_id		(GsCategory	*category);
+GsCategory	*gs_category_get_parent		(GsCategory	*category);
+
+const gchar	*gs_category_get_name		(GsCategory	*category);
+const gchar	*gs_category_get_icon_name	(GsCategory	*category);
+gint		 gs_category_get_score		(GsCategory	*category);
+
+GPtrArray	*gs_category_get_desktop_groups	(GsCategory	*category);
+gboolean	 gs_category_has_desktop_group	(GsCategory	*category,
+						 const gchar	*desktop_group);
+
+GsCategory	*gs_category_find_child		(GsCategory	*category,
+						 const gchar	*id);
+GPtrArray	*gs_category_get_children	(GsCategory	*category);
+
+guint		 gs_category_get_size		(GsCategory	*category);
+void		 gs_category_increment_size	(GsCategory	*category,
+						 guint		 value);
+
+G_END_DECLS
diff --git a/lib/gs-cmd.c b/lib/gs-cmd.c
new file mode 100644
index 0000000..895e1b8
--- /dev/null
+++ b/lib/gs-cmd.c
@@ -0,0 +1,847 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2013-2017 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2014-2015 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include "config.h"
+
+#include <glib/gi18n.h>
+#include <gtk/gtk.h>
+#include <locale.h>
+
+#include "gnome-software-private.h"
+
+#include "gs-debug.h"
+
+typedef struct {
+	GsPluginLoader	*plugin_loader;
+	guint64		 refine_flags;
+	guint		 max_results;
+	gboolean	 interactive;
+} GsCmdSelf;
+
+static void
+gs_cmd_show_results_apps (GsAppList *list)
+{
+	for (guint j = 0; j < gs_app_list_length (list); j++) {
+		GsApp *app = gs_app_list_index (list, j);
+		GsAppList *related = gs_app_get_related (app);
+		g_autofree gchar *tmp = gs_app_to_string (app);
+		g_print ("%s\n", tmp);
+		for (guint i = 0; i < gs_app_list_length (related); i++) {
+			g_autofree gchar *tmp_rel = NULL;
+			GsApp *app_rel = GS_APP (gs_app_list_index (related, i));
+			tmp_rel = gs_app_to_string (app_rel);
+			g_print ("\t%s\n", tmp_rel);
+		}
+	}
+}
+
+static gchar *
+gs_cmd_pad_spaces (const gchar *text, guint length)
+{
+	gsize i;
+	GString *str;
+	str = g_string_sized_new (length + 1);
+	g_string_append (str, text);
+	for (i = strlen (text); i < length; i++)
+		g_string_append_c (str, ' ');
+	return g_string_free (str, FALSE);
+}
+
+static void
+gs_cmd_show_results_categories (GPtrArray *list)
+{
+	for (guint i = 0; i < list->len; i++) {
+		GsCategory *cat = GS_CATEGORY (g_ptr_array_index (list, i));
+		GsCategory *parent = gs_category_get_parent (cat);
+		g_autofree gchar *tmp = NULL;
+		if (parent != NULL){
+			g_autofree gchar *id = NULL;
+			id = g_strdup_printf ("%s/%s [%u]",
+					      gs_category_get_id (parent),
+					      gs_category_get_id (cat),
+					      gs_category_get_size (cat));
+			tmp = gs_cmd_pad_spaces (id, 32);
+			g_print ("%s : %s\n",
+				 tmp, gs_category_get_name (cat));
+		} else {
+			GPtrArray *subcats = gs_category_get_children (cat);
+			tmp = gs_cmd_pad_spaces (gs_category_get_id (cat), 32);
+			g_print ("%s : %s\n",
+				 tmp, gs_category_get_name (cat));
+			gs_cmd_show_results_categories (subcats);
+		}
+	}
+}
+
+static GsPluginRefineFlags
+gs_cmd_refine_flag_from_string (const gchar *flag, GError **error)
+{
+	if (g_strcmp0 (flag, "all") == 0)
+		return G_MAXINT32;
+	if (g_strcmp0 (flag, "license") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_LICENSE;
+	if (g_strcmp0 (flag, "url") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_URL;
+	if (g_strcmp0 (flag, "description") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_DESCRIPTION;
+	if (g_strcmp0 (flag, "size") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_SIZE;
+	if (g_strcmp0 (flag, "rating") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_RATING;
+	if (g_strcmp0 (flag, "version") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_VERSION;
+	if (g_strcmp0 (flag, "history") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_HISTORY;
+	if (g_strcmp0 (flag, "setup-action") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_SETUP_ACTION;
+	if (g_strcmp0 (flag, "update-details") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_UPDATE_DETAILS;
+	if (g_strcmp0 (flag, "origin") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN;
+	if (g_strcmp0 (flag, "related") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_RELATED;
+	if (g_strcmp0 (flag, "menu-path") == 0)
+		/* no longer supported by itself; categories are largely equivalent */
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_CATEGORIES;
+	if (g_strcmp0 (flag, "upgrade-removed") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_UPGRADE_REMOVED;
+	if (g_strcmp0 (flag, "provenance") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_PROVENANCE;
+	if (g_strcmp0 (flag, "reviews") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_REVIEWS;
+	if (g_strcmp0 (flag, "review-ratings") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_REVIEW_RATINGS;
+	if (g_strcmp0 (flag, "key-colors") == 0)
+		/* no longer supported by itself; derived automatically from the icon */
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_ICON;
+	if (g_strcmp0 (flag, "icon") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_ICON;
+	if (g_strcmp0 (flag, "permissions") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_PERMISSIONS;
+	if (g_strcmp0 (flag, "origin-hostname") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN_HOSTNAME;
+	if (g_strcmp0 (flag, "origin-ui") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN_UI;
+	if (g_strcmp0 (flag, "runtime") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_RUNTIME;
+	if (g_strcmp0 (flag, "categories") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_CATEGORIES;
+	if (g_strcmp0 (flag, "project-group") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_PROJECT_GROUP;
+	if (g_strcmp0 (flag, "developer-name") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_DEVELOPER_NAME;
+	if (g_strcmp0 (flag, "kudos") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_KUDOS;
+	if (g_strcmp0 (flag, "content-rating") == 0)
+		return GS_PLUGIN_REFINE_FLAGS_REQUIRE_CONTENT_RATING;
+	g_set_error (error,
+		     GS_PLUGIN_ERROR,
+		     GS_PLUGIN_ERROR_NOT_SUPPORTED,
+		     "GsPluginRefineFlag '%s' not recognised", flag);
+	return 0;
+}
+
+static guint64
+gs_cmd_parse_refine_flags (const gchar *extra, GError **error)
+{
+	GsPluginRefineFlags tmp;
+	guint i;
+	guint64 refine_flags = GS_PLUGIN_REFINE_FLAGS_NONE;
+	g_auto(GStrv) split = NULL;
+
+	if (extra == NULL)
+		return GS_PLUGIN_REFINE_FLAGS_NONE;
+
+	split = g_strsplit (extra, ",", -1);
+	for (i = 0; split[i] != NULL; i++) {
+		tmp = gs_cmd_refine_flag_from_string (split[i], error);
+		if (tmp == 0)
+			return G_MAXUINT64;
+		refine_flags |= tmp;
+	}
+	return refine_flags;
+}
+
+static guint
+gs_cmd_prompt_for_number (guint maxnum)
+{
+	gint retval;
+	guint answer = 0;
+
+	do {
+		char buffer[64];
+
+		/* swallow the \n at end of line too */
+		if (!fgets (buffer, sizeof (buffer), stdin))
+			break;
+		if (strlen (buffer) == sizeof (buffer) - 1)
+			continue;
+
+		/* get a number */
+		retval = sscanf (buffer, "%u", &answer);
+
+		/* positive */
+		if (retval == 1 && answer > 0 && answer <= maxnum)
+			break;
+
+		/* TRANSLATORS: the user isn't reading the question */
+		g_print (_("Please enter a number from 1 to %u: "), maxnum);
+	} while (TRUE);
+	return answer;
+}
+
+static gboolean
+gs_cmd_action_exec (GsCmdSelf *self, GsPluginAction action, const gchar *name, GError **error)
+{
+	g_autoptr(GsApp) app = NULL;
+	g_autoptr(GsAppList) list = NULL;
+	g_autoptr(GsAppList) list_filtered = NULL;
+	g_autoptr(GsAppQuery) query = NULL;
+	g_autoptr(GsPluginJob) plugin_job2 = NULL;
+	g_autoptr(GsPluginJob) plugin_job = NULL;
+	gboolean show_installed = TRUE;
+	const gchar * const keywords[] = { name, NULL };
+	GsPluginListAppsFlags flags = GS_PLUGIN_LIST_APPS_FLAGS_NONE;
+
+	/* ensure set */
+	self->refine_flags |= GS_PLUGIN_REFINE_FLAGS_REQUIRE_ICON;
+	self->refine_flags |= GS_PLUGIN_REFINE_FLAGS_REQUIRE_SETUP_ACTION;
+
+	/* do search */
+	query = gs_app_query_new ("keywords", keywords,
+				  "refine-flags", self->refine_flags,
+				  "max-results", self->max_results,
+				  "dedupe-flags", GS_PLUGIN_JOB_DEDUPE_FLAGS_DEFAULT,
+				  "sort-func", gs_utils_app_sort_match_value,
+				  NULL);
+
+	if (self->interactive)
+		flags |= GS_PLUGIN_LIST_APPS_FLAGS_INTERACTIVE;
+
+	plugin_job = gs_plugin_job_list_apps_new (query, flags);
+	list = gs_plugin_loader_job_process (self->plugin_loader, plugin_job, NULL, error);
+	if (list == NULL)
+		return FALSE;
+	if (gs_app_list_length (list) == 0) {
+		g_set_error (error,
+			     GS_PLUGIN_ERROR,
+			     GS_PLUGIN_ERROR_FAILED,
+			     "no components matched '%s'",
+			     name);
+		return FALSE;
+	}
+
+	/* filter */
+	if (action == GS_PLUGIN_ACTION_INSTALL)
+		show_installed = FALSE;
+	list_filtered = gs_app_list_new ();
+	for (guint i = 0; i < gs_app_list_length (list); i++) {
+		GsApp *app_tmp = gs_app_list_index (list, i);
+		if (gs_app_is_installed (app_tmp) == show_installed)
+			gs_app_list_add (list_filtered, app_tmp);
+	}
+
+	/* nothing */
+	if (gs_app_list_length (list_filtered) == 0) {
+		g_set_error (error,
+			     GS_PLUGIN_ERROR,
+			     GS_PLUGIN_ERROR_FAILED,
+			     "no components were in the correct state for '%s %s'",
+			     gs_plugin_action_to_string (action), name);
+		return FALSE;
+	}
+
+	/* get one GsApp */
+	if (gs_app_list_length (list_filtered) == 1) {
+		app = g_object_ref (gs_app_list_index (list_filtered, 0));
+	} else {
+		guint idx;
+		/* TRANSLATORS: asking the user to choose an app from a list */
+		g_print ("%s\n", _("Choose an application:"));
+		for (guint i = 0; i < gs_app_list_length (list_filtered); i++) {
+			GsApp *app_tmp = gs_app_list_index (list_filtered, i);
+			g_print ("%u.\t%s\n",
+				 i + 1,
+				 gs_app_get_unique_id (app_tmp));
+		}
+		idx = gs_cmd_prompt_for_number (gs_app_list_length (list_filtered));
+		app = g_object_ref (gs_app_list_index (list_filtered, idx - 1));
+	}
+
+	/* install */
+	plugin_job2 = gs_plugin_job_newv (action,
+					  "app", app,
+					  "interactive", self->interactive,
+					  NULL);
+	return gs_plugin_loader_job_action (self->plugin_loader, plugin_job2,
+					    NULL, error);
+}
+
+static void
+gs_cmd_self_free (GsCmdSelf *self)
+{
+	if (self->plugin_loader != NULL)
+		g_object_unref (self->plugin_loader);
+	g_free (self);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC(GsCmdSelf, gs_cmd_self_free)
+
+static gint
+app_sort_kind_cb (GsApp *app1, GsApp *app2, gpointer user_data)
+{
+	if (gs_app_get_kind (app1) == AS_COMPONENT_KIND_DESKTOP_APP)
+		return -1;
+	if (gs_app_get_kind (app2) == AS_COMPONENT_KIND_DESKTOP_APP)
+		return 1;
+	return 0;
+}
+
+int
+main (int argc, char **argv)
+{
+	g_autoptr(GOptionContext) context = NULL;
+	gboolean prefer_local = FALSE;
+	gboolean ret;
+	gboolean show_results = FALSE;
+	gboolean verbose = FALSE;
+	gint i;
+	guint64 cache_age_secs = 0;
+	gint repeat = 1;
+	g_auto(GStrv) plugin_blocklist = NULL;
+	g_auto(GStrv) plugin_allowlist = NULL;
+	g_autoptr(GError) error = NULL;
+	g_autoptr(GsAppList) list = NULL;
+	g_autoptr(GPtrArray) categories = NULL;
+	g_autoptr(GsDebug) debug = gs_debug_new_from_environment ();
+	g_autofree gchar *plugin_blocklist_str = NULL;
+	g_autofree gchar *plugin_allowlist_str = NULL;
+	g_autofree gchar *refine_flags_str = NULL;
+	g_autoptr(GsApp) app = NULL;
+	g_autoptr(GFile) file = NULL;
+	g_autoptr(GsCmdSelf) self = g_new0 (GsCmdSelf, 1);
+	const GOptionEntry options[] = {
+		{ "show-results", '\0', 0, G_OPTION_ARG_NONE, &show_results,
+		  "Show the results for the action", NULL },
+		{ "refine-flags", '\0', 0, G_OPTION_ARG_STRING, &refine_flags_str,
+		  "Set any refine flags required for the action", NULL },
+		{ "repeat", '\0', 0, G_OPTION_ARG_INT, &repeat,
+		  "Repeat the action this number of times", NULL },
+		{ "cache-age", '\0', 0, G_OPTION_ARG_INT64, &cache_age_secs,
+		  "Use this maximum cache age in seconds", NULL },
+		{ "max-results", '\0', 0, G_OPTION_ARG_INT, &self->max_results,
+		  "Return a maximum number of results", NULL },
+		{ "prefer-local", '\0', 0, G_OPTION_ARG_NONE, &prefer_local,
+		  "Prefer local file sources to AppStream", NULL },
+		{ "plugin-blocklist", '\0', 0, G_OPTION_ARG_STRING, &plugin_blocklist_str,
+		  "Do not load specific plugins", NULL },
+		{ "plugin-allowlist", '\0', 0, G_OPTION_ARG_STRING, &plugin_allowlist_str,
+		  "Only load specific plugins", NULL },
+		{ "verbose", '\0', 0, G_OPTION_ARG_NONE, &verbose,
+		  "Show verbose debugging information", NULL },
+		{ "interactive", 'i', 0, G_OPTION_ARG_NONE, &self->interactive,
+		  "Allow interactive authentication", NULL },
+		{ NULL}
+	};
+
+	setlocale (LC_ALL, "");
+
+	bindtextdomain (GETTEXT_PACKAGE, LOCALEDIR);
+	bind_textdomain_codeset (GETTEXT_PACKAGE, "UTF-8");
+	textdomain (GETTEXT_PACKAGE);
+
+	gtk_init ();
+
+	context = g_option_context_new (NULL);
+	g_option_context_set_summary (context, "GNOME Software Test Program");
+	g_option_context_add_main_entries (context, options, NULL);
+	ret = g_option_context_parse (context, &argc, &argv, &error);
+	if (!ret) {
+		g_print ("Failed to parse options: %s\n", error->message);
+		return EXIT_FAILURE;
+	}
+	gs_debug_set_verbose (debug, verbose);
+
+	/* prefer local sources */
+	if (prefer_local)
+		g_setenv ("GNOME_SOFTWARE_PREFER_LOCAL", "true", TRUE);
+
+	/* parse any refine flags */
+	self->refine_flags = gs_cmd_parse_refine_flags (refine_flags_str, &error);
+	if (self->refine_flags == G_MAXUINT64) {
+		g_print ("Flag unknown: %s\n", error->message);
+		return EXIT_FAILURE;
+	}
+
+	/* load plugins */
+	self->plugin_loader = gs_plugin_loader_new (NULL, NULL);
+	if (g_file_test (LOCALPLUGINDIR, G_FILE_TEST_EXISTS))
+		gs_plugin_loader_add_location (self->plugin_loader, LOCALPLUGINDIR);
+	if (plugin_allowlist_str != NULL)
+		plugin_allowlist = g_strsplit (plugin_allowlist_str, ",", -1);
+	if (plugin_blocklist_str != NULL)
+		plugin_blocklist = g_strsplit (plugin_blocklist_str, ",", -1);
+	ret = gs_plugin_loader_setup (self->plugin_loader,
+				      (const gchar * const *) plugin_allowlist,
+				      (const gchar * const *) plugin_blocklist,
+				      NULL,
+				      &error);
+	if (!ret) {
+		g_print ("Failed to setup plugins: %s\n", error->message);
+		return EXIT_FAILURE;
+	}
+	gs_plugin_loader_dump_state (self->plugin_loader);
+
+	/* ensure that at least some metadata of any age is present, and also
+	 * spin up the plugins enough as to prime caches */
+	if (g_getenv ("GS_CMD_NO_INITIAL_REFRESH") == NULL) {
+		g_autoptr(GsPluginJob) plugin_job = NULL;
+		GsPluginRefreshMetadataFlags refresh_metadata_flags = GS_PLUGIN_REFRESH_METADATA_FLAGS_NONE;
+
+		if (self->interactive)
+			refresh_metadata_flags |= GS_PLUGIN_REFRESH_METADATA_FLAGS_INTERACTIVE;
+
+		plugin_job = gs_plugin_job_refresh_metadata_new (G_MAXUINT64, refresh_metadata_flags);
+		ret = gs_plugin_loader_job_action (self->plugin_loader, plugin_job,
+						    NULL, &error);
+		if (!ret) {
+			g_print ("Failed to refresh plugins: %s\n", error->message);
+			return EXIT_FAILURE;
+		}
+	}
+
+	/* do action */
+	if (argc == 2 && g_strcmp0 (argv[1], "installed") == 0) {
+		for (i = 0; i < repeat; i++) {
+			g_autoptr(GsAppQuery) query = NULL;
+			g_autoptr(GsPluginJob) plugin_job = NULL;
+			GsPluginListAppsFlags flags = GS_PLUGIN_LIST_APPS_FLAGS_NONE;
+
+			if (list != NULL)
+				g_object_unref (list);
+
+			query = gs_app_query_new ("is-installed", GS_APP_QUERY_TRISTATE_TRUE,
+						  "refine-flags", self->refine_flags,
+						  "max-results", self->max_results,
+						  "dedupe-flags", GS_PLUGIN_JOB_DEDUPE_FLAGS_DEFAULT,
+						  NULL);
+
+			if (self->interactive)
+				flags |= GS_PLUGIN_LIST_APPS_FLAGS_INTERACTIVE;
+
+			plugin_job = gs_plugin_job_list_apps_new (query, flags);
+			list = gs_plugin_loader_job_process (self->plugin_loader, plugin_job,
+							     NULL, &error);
+			if (list == NULL) {
+				ret = FALSE;
+				break;
+			}
+		}
+	} else if (argc == 3 && g_strcmp0 (argv[1], "search") == 0) {
+		for (i = 0; i < repeat; i++) {
+			g_autoptr(GsAppQuery) query = NULL;
+			g_autoptr(GsPluginJob) plugin_job = NULL;
+			GsPluginListAppsFlags flags = GS_PLUGIN_LIST_APPS_FLAGS_NONE;
+			const gchar *keywords[2] = { argv[2], NULL };
+
+			if (list != NULL)
+				g_object_unref (list);
+
+			query = gs_app_query_new ("keywords", keywords,
+						  "refine-flags", self->refine_flags,
+						  "max-results", self->max_results,
+						  "dedupe-flags", GS_PLUGIN_JOB_DEDUPE_FLAGS_DEFAULT,
+						  "sort-func", gs_utils_app_sort_match_value,
+						  NULL);
+
+			if (self->interactive)
+				flags |= GS_PLUGIN_LIST_APPS_FLAGS_INTERACTIVE;
+
+			plugin_job = gs_plugin_job_list_apps_new (query, flags);
+			list = gs_plugin_loader_job_process (self->plugin_loader, plugin_job, NULL, &error);
+			if (list == NULL) {
+				ret = FALSE;
+				break;
+			}
+		}
+	} else if (argc == 3 && g_strcmp0 (argv[1], "get-alternates") == 0) {
+		app = gs_app_new (argv[2]);
+		gs_app_add_quirk (app, GS_APP_QUIRK_IS_WILDCARD);
+		for (i = 0; i < repeat; i++) {
+			g_autoptr(GsAppQuery) query = NULL;
+			g_autoptr(GsPluginJob) plugin_job = NULL;
+			GsPluginListAppsFlags flags = GS_PLUGIN_LIST_APPS_FLAGS_NONE;
+
+			if (list != NULL)
+				g_object_unref (list);
+
+			query = gs_app_query_new ("alternate-of", app,
+						  "refine-flags", self->refine_flags,
+						  "max-results", self->max_results,
+						  "dedupe-flags", GS_PLUGIN_JOB_DEDUPE_FLAGS_DEFAULT,
+						  "sort-func", gs_utils_app_sort_priority,
+						  NULL);
+
+			if (self->interactive)
+				flags |= GS_PLUGIN_LIST_APPS_FLAGS_INTERACTIVE;
+
+			plugin_job = gs_plugin_job_list_apps_new (query, flags);
+			list = gs_plugin_loader_job_process (self->plugin_loader, plugin_job, NULL, &error);
+			if (list == NULL) {
+				ret = FALSE;
+				break;
+			}
+		}
+	} else if (argc == 4 && g_strcmp0 (argv[1], "action") == 0) {
+		GsPluginAction action = gs_plugin_action_from_string (argv[2]);
+		if (action == GS_PLUGIN_ACTION_UNKNOWN) {
+			ret = FALSE;
+			g_set_error (&error,
+				     GS_PLUGIN_ERROR,
+				     GS_PLUGIN_ERROR_FAILED,
+				     "Did not recognise action '%s'", argv[2]);
+		} else {
+			ret = gs_cmd_action_exec (self, action, argv[3], &error);
+		}
+	} else if (argc == 3 && g_strcmp0 (argv[1], "action-upgrade-download") == 0) {
+		g_autoptr(GsPluginJob) plugin_job = NULL;
+		app = gs_app_new (argv[2]);
+		gs_app_set_kind (app, AS_COMPONENT_KIND_OPERATING_SYSTEM);
+		plugin_job = gs_plugin_job_newv (GS_PLUGIN_ACTION_UPGRADE_DOWNLOAD,
+						 "app", app,
+						 "interactive", self->interactive,
+						 NULL);
+		ret = gs_plugin_loader_job_action (self->plugin_loader, plugin_job,
+						    NULL, &error);
+		if (ret)
+			gs_app_list_add (list, app);
+	} else if (argc == 3 && g_strcmp0 (argv[1], "refine") == 0) {
+		app = gs_app_new (argv[2]);
+		for (i = 0; i < repeat; i++) {
+			g_autoptr(GsPluginJob) plugin_job = NULL;
+			plugin_job = gs_plugin_job_refine_new_for_app (app, self->refine_flags);
+			ret = gs_plugin_loader_job_action (self->plugin_loader, plugin_job,
+							    NULL, &error);
+			if (!ret)
+				break;
+		}
+		list = gs_app_list_new ();
+		gs_app_list_add (list, app);
+	} else if (argc == 3 && g_strcmp0 (argv[1], "launch") == 0) {
+		app = gs_app_new (argv[2]);
+		for (i = 0; i < repeat; i++) {
+			g_autoptr(GsPluginJob) plugin_job = NULL;
+			plugin_job = gs_plugin_job_newv (GS_PLUGIN_ACTION_LAUNCH,
+							 "app", app,
+							 "interactive", self->interactive,
+							 NULL);
+			ret = gs_plugin_loader_job_action (self->plugin_loader, plugin_job,
+							    NULL, &error);
+			if (!ret)
+				break;
+		}
+	} else if (argc == 3 && g_strcmp0 (argv[1], "filename-to-app") == 0) {
+		g_autoptr(GsPluginJob) plugin_job = NULL;
+		file = g_file_new_for_path (argv[2]);
+		plugin_job = gs_plugin_job_newv (GS_PLUGIN_ACTION_FILE_TO_APP,
+						 "file", file,
+						 "refine-flags", self->refine_flags,
+						 "max-results", self->max_results,
+						 "interactive", self->interactive,
+						 NULL);
+		app = gs_plugin_loader_job_process_app (self->plugin_loader, plugin_job, NULL, &error);
+		if (app == NULL) {
+			ret = FALSE;
+		} else {
+			list = gs_app_list_new ();
+			gs_app_list_add (list, app);
+		}
+	} else if (argc == 3 && g_strcmp0 (argv[1], "url-to-app") == 0) {
+		g_autoptr(GsPluginJob) plugin_job = NULL;
+		plugin_job = gs_plugin_job_newv (GS_PLUGIN_ACTION_URL_TO_APP,
+						 "search", argv[2],
+						 "refine-flags", self->refine_flags,
+						 "max-results", self->max_results,
+						 "interactive", self->interactive,
+						 NULL);
+		app = gs_plugin_loader_job_process_app (self->plugin_loader, plugin_job,
+						    NULL, &error);
+		if (app == NULL) {
+			ret = FALSE;
+		} else {
+			list = gs_app_list_new ();
+			gs_app_list_add (list, app);
+		}
+	} else if (argc == 2 && g_strcmp0 (argv[1], "updates") == 0) {
+		for (i = 0; i < repeat; i++) {
+			g_autoptr(GsPluginJob) plugin_job = NULL;
+			if (list != NULL)
+				g_object_unref (list);
+			plugin_job = gs_plugin_job_newv (GS_PLUGIN_ACTION_GET_UPDATES,
+							 "refine-flags", self->refine_flags,
+							 "max-results", self->max_results,
+							 "interactive", self->interactive,
+							 NULL);
+			list = gs_plugin_loader_job_process (self->plugin_loader, plugin_job,
+							     NULL, &error);
+			if (list == NULL) {
+				ret = FALSE;
+				break;
+			}
+		}
+	} else if (argc == 2 && g_strcmp0 (argv[1], "upgrades") == 0) {
+		for (i = 0; i < repeat; i++) {
+			g_autoptr(GsPluginJob) plugin_job = NULL;
+			GsPluginListDistroUpgradesFlags upgrades_flags = GS_PLUGIN_LIST_DISTRO_UPGRADES_FLAGS_NONE;
+
+			if (list != NULL)
+				g_object_unref (list);
+
+			if (self->interactive)
+				upgrades_flags |= GS_PLUGIN_LIST_DISTRO_UPGRADES_FLAGS_INTERACTIVE;
+
+			plugin_job = gs_plugin_job_list_distro_upgrades_new (upgrades_flags, self->refine_flags);
+			list = gs_plugin_loader_job_process (self->plugin_loader, plugin_job,
+							     NULL, &error);
+			if (list == NULL) {
+				ret = FALSE;
+				break;
+			}
+		}
+	} else if (argc == 2 && g_strcmp0 (argv[1], "sources") == 0) {
+		g_autoptr(GsPluginJob) plugin_job = NULL;
+		plugin_job = gs_plugin_job_newv (GS_PLUGIN_ACTION_GET_SOURCES,
+						 "refine-flags", self->refine_flags,
+						 "max-results", self->max_results,
+						 "interactive", self->interactive,
+						 NULL);
+		list = gs_plugin_loader_job_process (self->plugin_loader,
+						     plugin_job,
+						     NULL,
+						     &error);
+		if (list == NULL)
+			ret = FALSE;
+	} else if (argc == 2 && g_strcmp0 (argv[1], "popular") == 0) {
+		for (i = 0; i < repeat; i++) {
+			g_autoptr(GsPluginJob) plugin_job = NULL;
+			g_autoptr(GsAppQuery) query = NULL;
+			GsPluginListAppsFlags flags = GS_PLUGIN_LIST_APPS_FLAGS_NONE;
+
+			if (list != NULL)
+				g_object_unref (list);
+
+			query = gs_app_query_new ("is-curated", GS_APP_QUERY_TRISTATE_TRUE,
+						  "refine-flags", self->refine_flags,
+						  "max-results", self->max_results,
+						  "sort-func", app_sort_kind_cb,
+						  NULL);
+
+			if (self->interactive)
+				flags |= GS_PLUGIN_LIST_APPS_FLAGS_INTERACTIVE;
+
+			plugin_job = gs_plugin_job_list_apps_new (query, flags);
+			list = gs_plugin_loader_job_process (self->plugin_loader, plugin_job,
+							     NULL, &error);
+			if (list == NULL) {
+				ret = FALSE;
+				break;
+			}
+		}
+	} else if (argc == 2 && g_strcmp0 (argv[1], "featured") == 0) {
+		for (i = 0; i < repeat; i++) {
+			g_autoptr(GsPluginJob) plugin_job = NULL;
+			g_autoptr(GsAppQuery) query = NULL;
+			GsPluginListAppsFlags flags = GS_PLUGIN_LIST_APPS_FLAGS_NONE;
+
+			if (list != NULL)
+				g_object_unref (list);
+
+			query = gs_app_query_new ("is-featured", GS_APP_QUERY_TRISTATE_TRUE,
+						  "refine-flags", self->refine_flags,
+						  "max-results", self->max_results,
+						  NULL);
+
+			if (self->interactive)
+				flags |= GS_PLUGIN_LIST_APPS_FLAGS_INTERACTIVE;
+
+			plugin_job = gs_plugin_job_list_apps_new (query, flags);
+			list = gs_plugin_loader_job_process (self->plugin_loader, plugin_job,
+							     NULL, &error);
+
+			if (list == NULL) {
+				ret = FALSE;
+				break;
+			}
+		}
+	} else if (argc == 3 && g_strcmp0 (argv[1], "deployment-featured") == 0) {
+		g_auto(GStrv) split = g_strsplit (argv[2], ",", -1);
+		for (i = 0; i < repeat; i++) {
+			g_autoptr(GsPluginJob) plugin_job = NULL;
+			g_autoptr(GsAppQuery) query = NULL;
+			GsPluginListAppsFlags flags = GS_PLUGIN_LIST_APPS_FLAGS_NONE;
+
+			if (list != NULL)
+				g_object_unref (list);
+
+			query = gs_app_query_new ("deployment-featured", split,
+						  "refine-flags", self->refine_flags,
+						  "dedupe-flags", GS_APP_LIST_FILTER_FLAG_KEY_ID,
+						  "max-results", self->max_results,
+						  NULL);
+
+			if (self->interactive)
+				flags |= GS_PLUGIN_LIST_APPS_FLAGS_INTERACTIVE;
+
+			plugin_job = gs_plugin_job_list_apps_new (query, flags);
+			list = gs_plugin_loader_job_process (self->plugin_loader, plugin_job,
+							     NULL, &error);
+			if (list == NULL) {
+				ret = FALSE;
+				break;
+			}
+		}
+	} else if (argc == 2 && g_strcmp0 (argv[1], "recent") == 0) {
+		if (cache_age_secs == 0)
+			cache_age_secs = 60 * 60 * 24 * 60;
+		for (i = 0; i < repeat; i++) {
+			g_autoptr(GsPluginJob) plugin_job = NULL;
+			g_autoptr(GDateTime) now = NULL;
+			g_autoptr(GDateTime) released_since = NULL;
+			g_autoptr(GsAppQuery) query = NULL;
+			GsPluginListAppsFlags flags = GS_PLUGIN_LIST_APPS_FLAGS_NONE;
+
+			if (list != NULL)
+				g_object_unref (list);
+
+			now = g_date_time_new_now_local ();
+			released_since = g_date_time_add_seconds (now, -cache_age_secs);
+			query = gs_app_query_new ("released-since", released_since,
+						  "refine-flags", self->refine_flags,
+						  "dedupe-flags", GS_APP_LIST_FILTER_FLAG_KEY_ID,
+						  "max-results", self->max_results,
+						  "sort-func", app_sort_kind_cb,
+						  NULL);
+
+			if (self->interactive)
+				flags |= GS_PLUGIN_LIST_APPS_FLAGS_INTERACTIVE;
+
+			plugin_job = gs_plugin_job_list_apps_new (query, flags);
+			list = gs_plugin_loader_job_process (self->plugin_loader, plugin_job,
+							     NULL, &error);
+			if (list == NULL) {
+				ret = FALSE;
+				break;
+			}
+		}
+	} else if (argc == 2 && g_strcmp0 (argv[1], "get-categories") == 0) {
+		for (i = 0; i < repeat; i++) {
+			g_autoptr(GsPluginJob) plugin_job = NULL;
+			GsPluginRefineCategoriesFlags flags = GS_PLUGIN_REFINE_CATEGORIES_FLAGS_SIZE;
+
+			if (categories != NULL)
+				g_ptr_array_unref (categories);
+
+			if (self->interactive)
+				flags |= GS_PLUGIN_REFINE_CATEGORIES_FLAGS_INTERACTIVE;
+
+			plugin_job = gs_plugin_job_list_categories_new (flags);
+			if (!gs_plugin_loader_job_action (self->plugin_loader, plugin_job, NULL, &error)) {
+				ret = FALSE;
+				break;
+			}
+
+			categories = g_ptr_array_ref (gs_plugin_job_list_categories_get_result_list (GS_PLUGIN_JOB_LIST_CATEGORIES (plugin_job)));
+		}
+	} else if (argc == 3 && g_strcmp0 (argv[1], "get-category-apps") == 0) {
+		g_autoptr(GsCategory) category_owned = NULL;
+		GsCategory *category = NULL;
+		g_auto(GStrv) split = NULL;
+		GsCategoryManager *manager = gs_plugin_loader_get_category_manager (self->plugin_loader);
+
+		split = g_strsplit (argv[2], "/", 2);
+		if (g_strv_length (split) == 1) {
+			category_owned = gs_category_manager_lookup (manager, split[0]);
+			category = category_owned;
+		} else {
+			g_autoptr(GsCategory) parent = gs_category_manager_lookup (manager, split[0]);
+			if (parent != NULL)
+				category = gs_category_find_child (parent, split[1]);
+		}
+
+		if (category == NULL) {
+			g_printerr ("Error: Could not find category ‘%s’\n", argv[2]);
+			return EXIT_FAILURE;
+		}
+
+		for (i = 0; i < repeat; i++) {
+			g_autoptr(GsPluginJob) plugin_job = NULL;
+			g_autoptr(GsAppQuery) query = NULL;
+			GsPluginListAppsFlags flags = GS_PLUGIN_LIST_APPS_FLAGS_NONE;
+
+			if (list != NULL)
+				g_object_unref (list);
+
+			query = gs_app_query_new ("category", category,
+						  "refine-flags", self->refine_flags,
+						  "max-results", self->max_results,
+						  "sort-func", gs_utils_app_sort_name,
+						  NULL);
+
+			if (self->interactive)
+				flags |= GS_PLUGIN_LIST_APPS_FLAGS_INTERACTIVE;
+
+			plugin_job = gs_plugin_job_list_apps_new (query, flags);
+			list = gs_plugin_loader_job_process (self->plugin_loader, plugin_job, NULL, &error);
+			if (list == NULL) {
+				ret = FALSE;
+				break;
+			}
+		}
+	} else if (argc >= 2 && g_strcmp0 (argv[1], "refresh") == 0) {
+		g_autoptr(GsPluginJob) plugin_job = NULL;
+		GsPluginRefreshMetadataFlags refresh_metadata_flags = GS_PLUGIN_REFRESH_METADATA_FLAGS_NONE;
+
+		if (self->interactive)
+			refresh_metadata_flags |= GS_PLUGIN_REFRESH_METADATA_FLAGS_INTERACTIVE;
+
+		plugin_job = gs_plugin_job_refresh_metadata_new (cache_age_secs, refresh_metadata_flags);
+		ret = gs_plugin_loader_job_action (self->plugin_loader, plugin_job,
+						    NULL, &error);
+	} else if (argc >= 1 && g_strcmp0 (argv[1], "user-hash") == 0) {
+		g_autofree gchar *user_hash = gs_utils_get_user_hash (&error);
+		if (user_hash == NULL) {
+			ret = FALSE;
+		} else {
+			g_print ("%s\n", user_hash);
+			ret = TRUE;
+		}
+	} else {
+		ret = FALSE;
+		g_set_error_literal (&error,
+				     GS_PLUGIN_ERROR,
+				     GS_PLUGIN_ERROR_FAILED,
+				     "Did not recognise option, use 'installed', "
+				     "'updates', 'popular', 'get-categories', "
+				     "'get-category-apps', 'get-alternates', 'filename-to-app', "
+				     "'action install', 'action remove', "
+				     "'sources', 'refresh', 'launch' or 'search'");
+	}
+	if (!ret) {
+		g_print ("Failed: %s\n", error->message);
+		return EXIT_FAILURE;
+	}
+
+	if (show_results) {
+		if (list != NULL)
+			gs_cmd_show_results_apps (list);
+		if (categories != NULL)
+			gs_cmd_show_results_categories (categories);
+	}
+	return EXIT_SUCCESS;
+}
diff --git a/lib/gs-debug.c b/lib/gs-debug.c
new file mode 100644
index 0000000..f76788a
--- /dev/null
+++ b/lib/gs-debug.c
@@ -0,0 +1,295 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2016 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2017 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include "config.h"
+
+#include <stdio.h>
+#include <unistd.h>
+
+#include "gs-os-release.h"
+#include "gs-debug.h"
+
+struct _GsDebug
+{
+	GObject		  parent_instance;
+
+	gchar		**domains;  /* (owned) (nullable), read-only after construction, guaranteed to be %NULL if empty */
+	gboolean	  verbose;  /* (atomic) */
+	gboolean	  use_time;  /* read-only after construction */
+};
+
+G_DEFINE_TYPE (GsDebug, gs_debug, G_TYPE_OBJECT)
+
+static GLogWriterOutput
+gs_log_writer_console (GLogLevelFlags log_level,
+		       const GLogField *fields,
+		       gsize n_fields,
+		       gpointer user_data)
+{
+	GsDebug *debug = GS_DEBUG (user_data);
+	gboolean verbose;
+	const gchar * const *domains = NULL;
+	const gchar *log_domain = NULL;
+	const gchar *log_message = NULL;
+	g_autofree gchar *tmp = NULL;
+	g_autoptr(GString) domain = NULL;
+
+	domains = (const gchar * const *) debug->domains;
+	verbose = g_atomic_int_get (&debug->verbose);
+
+	/* check enabled, fast path without parsing fields */
+	if ((log_level == G_LOG_LEVEL_DEBUG ||
+	     log_level == G_LOG_LEVEL_INFO) &&
+	    !verbose &&
+	    debug->domains == NULL)
+		return G_LOG_WRITER_HANDLED;
+
+	/* get data from arguments */
+	for (gsize i = 0; i < n_fields; i++) {
+		if (g_strcmp0 (fields[i].key, "MESSAGE") == 0) {
+			log_message = fields[i].value;
+			continue;
+		}
+		if (g_strcmp0 (fields[i].key, "GLIB_DOMAIN") == 0) {
+			log_domain = fields[i].value;
+			continue;
+		}
+	}
+
+	/* check enabled, slower path */
+	if ((log_level == G_LOG_LEVEL_DEBUG ||
+	     log_level == G_LOG_LEVEL_INFO) &&
+	    !verbose &&
+	    debug->domains != NULL &&
+	    g_strcmp0 (debug->domains[0], "all") != 0 &&
+	    (log_domain == NULL || !g_strv_contains (domains, log_domain)))
+		return G_LOG_WRITER_HANDLED;
+
+	/* this is really verbose */
+	if ((g_strcmp0 (log_domain, "dconf") == 0 ||
+	     g_strcmp0 (log_domain, "GLib-GIO") == 0 ||
+	     g_strcmp0 (log_domain, "GLib-Net") == 0 ||
+	     g_strcmp0 (log_domain, "GdkPixbuf") == 0) &&
+	    log_level == G_LOG_LEVEL_DEBUG)
+		return G_LOG_WRITER_HANDLED;
+
+	/* time header */
+	if (debug->use_time) {
+		g_autoptr(GDateTime) dt = g_date_time_new_now_utc ();
+		tmp = g_strdup_printf ("%02i:%02i:%02i:%03i",
+				       g_date_time_get_hour (dt),
+				       g_date_time_get_minute (dt),
+				       g_date_time_get_second (dt),
+				       g_date_time_get_microsecond (dt) / 1000);
+	}
+
+	/* make these shorter */
+	if (g_strcmp0 (log_domain, "PackageKit") == 0) {
+		log_domain = "PK";
+	} else if (g_strcmp0 (log_domain, "GsPlugin") == 0) {
+		log_domain = "Gs";
+	}
+
+	/* pad out domain */
+	domain = g_string_new (log_domain);
+	for (guint i = domain->len; i < 3; i++)
+		g_string_append (domain, " ");
+
+	switch (log_level) {
+	case G_LOG_LEVEL_ERROR:
+	case G_LOG_LEVEL_CRITICAL:
+	case G_LOG_LEVEL_WARNING:
+		/* to screen */
+		if (isatty (fileno (stderr)) == 1) {
+			/* critical in red */
+			if (tmp != NULL)
+				g_printerr ("%c[%dm%s ", 0x1B, 32, tmp);
+			g_printerr ("%s ", domain->str);
+			g_printerr ("%c[%dm%s\n%c[%dm", 0x1B, 31, log_message, 0x1B, 0);
+		} else { /* to file */
+			if (tmp != NULL)
+				g_printerr ("%s ", tmp);
+			g_printerr ("%s ", domain->str);
+			g_printerr ("%s\n", log_message);
+		}
+		break;
+	default:
+		/* to screen */
+		if (isatty (fileno (stdout)) == 1) {
+			/* debug in blue */
+			if (tmp != NULL)
+				g_print ("%c[%dm%s ", 0x1B, 32, tmp);
+			g_print ("%s ", domain->str);
+			g_print ("%c[%dm%s\n%c[%dm", 0x1B, 34, log_message, 0x1B, 0);
+			break;
+		} else { /* to file */
+			if (tmp != NULL)
+				g_print ("%s ", tmp);
+			g_print ("%s ", domain->str);
+			g_print ("%s\n", log_message);
+		}
+	}
+
+	/* success */
+	return G_LOG_WRITER_HANDLED;
+}
+
+static GLogWriterOutput
+gs_log_writer_journald (GLogLevelFlags log_level,
+                        const GLogField *fields,
+                        gsize n_fields,
+                        gpointer user_data)
+{
+	/* important enough to force to the journal */
+	switch (log_level) {
+	case G_LOG_LEVEL_ERROR:
+	case G_LOG_LEVEL_CRITICAL:
+	case G_LOG_LEVEL_WARNING:
+	case G_LOG_LEVEL_INFO:
+		return g_log_writer_journald (log_level, fields, n_fields, user_data);
+		break;
+	default:
+		break;
+	}
+
+	return G_LOG_WRITER_UNHANDLED;
+}
+
+static GLogWriterOutput
+gs_debug_log_writer (GLogLevelFlags log_level,
+		     const GLogField *fields,
+		     gsize n_fields,
+		     gpointer user_data)
+{
+	if (g_log_writer_is_journald (fileno (stderr)))
+		return gs_log_writer_journald (log_level, fields, n_fields, user_data);
+	else
+		return gs_log_writer_console (log_level, fields, n_fields, user_data);
+}
+
+static void
+gs_debug_finalize (GObject *object)
+{
+	GsDebug *debug = GS_DEBUG (object);
+
+	g_clear_pointer (&debug->domains, g_strfreev);
+
+	G_OBJECT_CLASS (gs_debug_parent_class)->finalize (object);
+}
+
+static void
+gs_debug_class_init (GsDebugClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+	object_class->finalize = gs_debug_finalize;
+}
+
+static void
+gs_debug_init (GsDebug *debug)
+{
+	g_log_set_writer_func (gs_debug_log_writer,
+			       g_object_ref (debug),
+			       (GDestroyNotify) g_object_unref);
+}
+
+/**
+ * gs_debug_new:
+ * @domains: (transfer full) (nullable): a #GStrv of debug log domains to output,
+ *     or `{ "all", NULL }` to output all debug log domains; %NULL is equivalent
+ *     to an empty array
+ * @verbose: whether to output log debug messages
+ * @use_time: whether to output a timestamp with each log message
+ *
+ * Create a new #GsDebug with the given configuration.
+ *
+ * Ownership of @domains is transferred to this function. It will be freed with
+ * g_strfreev() when the #GsDebug is destroyed.
+ *
+ * Returns: (transfer full): a new #GsDebug
+ * Since: 40
+ */
+GsDebug *
+gs_debug_new (gchar    **domains,
+              gboolean   verbose,
+              gboolean   use_time)
+{
+	g_autoptr(GsDebug) debug = g_object_new (GS_TYPE_DEBUG, NULL);
+
+	/* Strictly speaking these should be set before g_log_set_writer_func()
+	 * is called, but threads probably haven’t been started at this point. */
+	debug->domains = (domains != NULL && domains[0] != NULL) ? g_steal_pointer (&domains) : NULL;
+	debug->verbose = verbose;
+	debug->use_time = use_time;
+
+	return g_steal_pointer (&debug);
+}
+
+/**
+ * gs_debug_new_from_environment:
+ *
+ * Create a new #GsDebug with its configuration loaded from environment
+ * variables.
+ *
+ * Returns: (transfer full): a new #GsDebug
+ * Since: 40
+ */
+GsDebug *
+gs_debug_new_from_environment (void)
+{
+	g_auto(GStrv) domains = NULL;
+	gboolean verbose, use_time;
+
+	if (g_getenv ("G_MESSAGES_DEBUG") != NULL) {
+		domains = g_strsplit (g_getenv ("G_MESSAGES_DEBUG"), " ", -1);
+		if (domains[0] == NULL)
+			g_clear_pointer (&domains, g_strfreev);
+	}
+
+	verbose = (g_getenv ("GS_DEBUG") != NULL);
+	use_time = (g_getenv ("GS_DEBUG_NO_TIME") == NULL);
+
+	return gs_debug_new (g_steal_pointer (&domains), verbose, use_time);
+}
+
+/**
+ * gs_debug_set_verbose:
+ * @self: a #GsDebug
+ * @verbose: whether to output log debug messages
+ *
+ * Enable or disable verbose logging mode.
+ *
+ * This can be called at any time, from any thread.
+ *
+ * Since: 40
+ */
+void
+gs_debug_set_verbose (GsDebug  *self,
+                      gboolean  verbose)
+{
+	g_return_if_fail (GS_IS_DEBUG (self));
+
+	/* If we’re changing from !verbose → verbose, print OS information.
+	 * This is helpful in verbose logs when people file bug reports. */
+	if (g_atomic_int_compare_and_exchange (&self->verbose, !verbose, verbose) &&
+	    verbose) {
+		g_autoptr(GsOsRelease) os_release = NULL;
+		g_autoptr(GError) error = NULL;
+
+		g_debug (PACKAGE_NAME " " PACKAGE_VERSION);
+
+		os_release = gs_os_release_new (&error);
+		if (os_release) {
+			g_debug ("OS: %s; %s",
+				gs_os_release_get_name (os_release),
+				gs_os_release_get_version (os_release));
+		} else {
+			g_debug ("Failed to get OS Release information: %s", error->message);
+		}
+	}
+}
diff --git a/lib/gs-debug.h b/lib/gs-debug.h
new file mode 100644
index 0000000..d927f81
--- /dev/null
+++ b/lib/gs-debug.h
@@ -0,0 +1,27 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2016 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <glib-object.h>
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_DEBUG (gs_debug_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsDebug, gs_debug, GS, DEBUG, GObject)
+
+GsDebug		*gs_debug_new		(gchar		**domains,
+					 gboolean	  verbose,
+					 gboolean	  use_time);
+GsDebug		*gs_debug_new_from_environment	(void);
+void		 gs_debug_set_verbose	(GsDebug	*self,
+					 gboolean	 verbose);
+
+G_END_DECLS
diff --git a/lib/gs-desktop-data.c b/lib/gs-desktop-data.c
new file mode 100644
index 0000000..c2ee93b
--- /dev/null
+++ b/lib/gs-desktop-data.c
@@ -0,0 +1,320 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2015-2016 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include "config.h"
+
+#include <glib/gi18n.h>
+
+#include "gs-desktop-data.h"
+
+static const GsDesktopMap map_create[] = {
+	{ "all",		NC_("Menu of Graphics & Photography", "All"),
+					{ "Graphics",
+					  "AudioVideo",
+					  NULL } },
+	{ "featured",		NC_("Menu of Graphics & Photography", "Featured"),
+					{ "Graphics::Featured",
+					  "AudioVideo::Featured",
+					  NULL} },
+	{ "3d",			NC_("Menu of Graphics & Photography", "3D Graphics"),
+					{ "Graphics::3DGraphics",
+					  NULL} },
+	{ "photography",	NC_("Menu of Graphics & Photography", "Photography"),
+					{ "Graphics::Photography",
+					  NULL} },
+	{ "scanning",		NC_("Menu of Graphics & Photography", "Scanning"),
+					{ "Graphics::Scanning",
+					  NULL} },
+	{ "vector",		NC_("Menu of Graphics & Photography", "Vector Graphics"),
+					{ "Graphics::VectorGraphics",
+					  NULL} },
+	{ "viewers",		NC_("Menu of Graphics & Photography", "Viewers"),
+					{ "Graphics::Viewer",
+					  NULL} },
+	{ "creation-editing",	NC_("Menu of Audio & Video", "Audio Creation & Editing"),
+					{ "AudioVideo::AudioVideoEditing",
+					  "AudioVideo::Midi",
+					  "AudioVideo::DiscBurning",
+					  "AudioVideo::Sequencer",
+					  NULL} },
+	{ "music-players",	NC_("Menu of Audio & Video", "Music Players"),
+					{ "AudioVideo::Music",
+					  "AudioVideo::Player",
+					  NULL} },
+	{ NULL }
+};
+
+static const GsDesktopMap map_work[] = {
+	{ "all",		NC_("Menu of Productivity", "All"),
+					{ "Office",
+					  "Utility",
+					  "Network::WebBrowser",
+					  NULL } },
+	{ "featured",		NC_("Menu of Productivity", "Featured"),
+					{ "Office::Featured",
+					  "Utility::Featured",
+					  NULL} },
+	{ "calendar",		NC_("Menu of Productivity", "Calendar"),
+					{ "Office::Calendar",
+					  "Office::ProjectManagement",
+					  NULL} },
+	{ "database",		NC_("Menu of Productivity", "Database"),
+					{ "Office::Database",
+					  NULL} },
+	{ "finance",		NC_("Menu of Productivity", "Finance"),
+					{ "Office::Finance",
+					  "Office::Spreadsheet",
+					  NULL} },
+	{ "word-processor",	NC_("Menu of Productivity", "Word Processor"),
+					{ "Office::WordProcessor",
+					  "Office::Dictionary",
+					  NULL} },
+	{ "text-editors",	NC_("Menu of Utilities", "Text Editors"),
+					{ "Utility::TextEditor",
+					  NULL} },
+	{ "web-browsers",	NC_("Menu of Communication & News", "Web Browsers"),
+					{ "Network::WebBrowser",
+					  NULL} },
+	{ NULL }
+};
+
+static const GsDesktopMap map_play[] = {
+	{ "all",		NC_("Menu of Audio & Video", "All"),
+					{ "Game",
+					  NULL } },
+	{ "featured",		NC_("Menu of Audio & Video", "Featured"),
+					{ "Game::Featured",
+					  NULL} },
+	{ "action",		NC_("Menu of Games", "Action"),
+					{ "Game::ActionGame",
+					  NULL} },
+	{ "adventure",		NC_("Menu of Games", "Adventure"),
+					{ "Game::AdventureGame",
+					  NULL} },
+	{ "arcade",		NC_("Menu of Games", "Arcade"),
+					{ "Game::ArcadeGame",
+					  NULL} },
+	{ "blocks",		NC_("Menu of Games", "Blocks"),
+					{ "Game::BlocksGame",
+					  NULL} },
+	{ "board",		NC_("Menu of Games", "Board"),
+					{ "Game::BoardGame",
+					  NULL} },
+	{ "card",		NC_("Menu of Games", "Card"),
+					{ "Game::CardGame",
+					  NULL} },
+	{ "emulator",		NC_("Menu of Games", "Emulators"),
+					{ "Game::Emulator",
+					  NULL} },
+	{ "kids",		NC_("Menu of Games", "Kids"),
+					{ "Game::KidsGame",
+					  NULL} },
+	{ "logic",		NC_("Menu of Games", "Logic"),
+					{ "Game::LogicGame",
+					  "Game::Simulation",
+					  NULL} },
+	{ "role-playing",	NC_("Menu of Games", "Role Playing"),
+					{ "Game::RolePlaying",
+					  NULL} },
+	{ "sports",		NC_("Menu of Games", "Sports"),
+					{ "Game::SportsGame",
+					  NULL} },
+	{ "strategy",		NC_("Menu of Games", "Strategy"),
+					{ "Game::StrategyGame",
+					  NULL} },
+	{ NULL }
+};
+
+static const GsDesktopMap map_socialize[] = {
+	{ "all",		NC_("Menu of Communication & News", "All"),
+					{ "Network",
+					  NULL } },
+	{ "featured",		NC_("Menu of Communication & News", "Featured"),
+					{ "Network::Featured",
+					  NULL} },
+	{ "chat",		NC_("Menu of Communication & News", "Chat"),
+					{ "Network::Chat",
+					  "Network::IRCClient",
+					  "Network::Telephony",
+					  "Network::VideoConference",
+					  "Network::Email",
+					  NULL} },
+	{ NULL }
+};
+
+static const GsDesktopMap map_learn[] = {
+	{ "all",		NC_("Menu of Education & Science", "All"),
+					{ "Education",
+					  "Science",
+					  "Reference",
+					  "Network::Feed",
+					  "Network::News",
+					  NULL } },
+	{ "featured",		NC_("Menu of Education & Science", "Featured"),
+					{ "Education::Featured",
+					  "Science::Featured",
+					  "Reference::Featured",
+					  NULL} },
+	{ "artificial-intelligence", NC_("Menu of Education & Science", "Artificial Intelligence"),
+					{ "Science::ArtificialIntelligence",
+					  NULL} },
+	{ "astronomy",		NC_("Menu of Education & Science", "Astronomy"),
+					{ "Education::Astronomy",
+					  "Science::Astronomy",
+					  NULL} },
+	{ "chemistry",		NC_("Menu of Education & Science", "Chemistry"),
+					{ "Education::Chemistry",
+					  "Science::Chemistry",
+					  NULL} },
+	{ "languages",		NC_("Menu of Education & Science", "Languages"),
+					{ "Education::Languages",
+					  "Education::Literature",
+					  NULL} },
+	{ "math",		NC_("Menu of Education & Science", "Math"),
+					{ "Education::Math",
+					  "Education::NumericalAnalysis",
+					  "Science::Math",
+					  "Science::Physics",
+					  "Science::NumericalAnalysis",
+					  NULL} },
+	{ "news",		NC_("Menu of Communication & News", "News"),
+					{ "Network::Feed",
+					  "Network::News",
+					  NULL} },
+	{ "robotics",		NC_("Menu of Education & Science", "Robotics"),
+					{ "Science::Robotics",
+					  NULL} },
+	{ "art",		NC_("Menu of Art", "Art"),
+					{ "Reference::Art",
+					  NULL} },
+	{ "biography",		NC_("Menu of Reference", "Biography"),
+					{ "Reference::Biography",
+					  NULL} },
+	{ "comics",		NC_("Menu of Reference", "Comics"),
+					{ "Reference::Comics",
+					  NULL} },
+	{ "fiction",		NC_("Menu of Reference", "Fiction"),
+					{ "Reference::Fiction",
+					  NULL} },
+	{ "health",		NC_("Menu of Reference", "Health"),
+					{ "Reference::Health",
+					  NULL} },
+	{ "history",		NC_("Menu of Reference", "History"),
+					{ "Reference::History",
+					  NULL} },
+	{ "lifestyle",		NC_("Menu of Reference", "Lifestyle"),
+					{ "Reference::Lifestyle",
+					  NULL} },
+	{ "politics",		NC_("Menu of Reference", "Politics"),
+					{ "Reference::Politics",
+					  NULL} },
+	{ "sports",		NC_("Menu of Reference", "Sports"),
+					{ "Reference::Sports",
+					  NULL} },
+	{ NULL }
+};
+
+static const GsDesktopMap map_develop[] = {
+	{ "all",		NC_("Menu of Developer Tools", "All"),
+					{ "Development",
+					  NULL } },
+	{ "featured",		NC_("Menu of Developer Tools", "Featured"),
+					{ "Development::Featured",
+					  NULL} },
+	{ "debuggers",		NC_("Menu of Developer Tools", "Debuggers"),
+					{ "Development::Debugger",
+					  NULL} },
+	{ "ide",		NC_("Menu of Developer Tools", "IDEs"),
+					{ "Development::IDE",
+					  "Development::GUIDesigner",
+					  NULL} },
+	{ NULL }
+};
+
+static const GsDesktopMap map_addon_codecs[] = {
+	{ "all",		NC_("Menu of Add-ons", "Codecs"),
+					{ "Addon::Codec",
+					  NULL } },
+	{ NULL }
+};
+
+static const GsDesktopMap map_addon_drivers[] = {
+	{ "all",		NC_("Menu of Add-ons", "Hardware Drivers"),
+					{ "Addon::Driver",
+					  NULL } },
+	{ NULL }
+};
+
+static const GsDesktopMap map_addon_fonts[] = {
+	{ "all",		NC_("Menu of Add-ons", "Fonts"),
+					{ "Addon::Font",
+					  NULL } },
+	{ NULL }
+};
+
+static const GsDesktopMap map_addon_input_sources[] = {
+	{ "all",		NC_("Menu of Add-ons", "Input Sources"),
+					{ "Addon::InputSource",
+					  NULL } },
+	{ NULL }
+};
+
+static const GsDesktopMap map_addon_language_packs[] = {
+	{ "all",		NC_("Menu of Add-ons", "Language Packs"),
+					{ "Addon::LanguagePack",
+					  NULL } },
+	{ NULL }
+};
+
+static const GsDesktopMap map_addon_localization[] = {
+	{ "all",		NC_("Menu of Add-ons", "Localization"),
+					{ "Addon::Localization",
+					  NULL } },
+	{ NULL }
+};
+
+/* main categories */
+/* Please keep category name and subcategory context synchronized!!! */
+static const GsDesktopData msdata[] = {
+	/* Translators: this is a menu category */
+	{ "create", map_create, N_("Create"), "org.gnome.Software.Create", 100 },
+	/* Translators: this is a menu category */
+	{ "work", map_work, N_("Work"), "org.gnome.Software.Work", 90 },
+	/* Translators: this is a menu category */
+	{ "play", map_play, N_("Play"), "org.gnome.Software.Play", 80 },
+	/* Translators: this is a menu category */
+	{ "socialize", map_socialize, N_("Socialize"), "org.gnome.Software.Socialize", 70 },
+	/* Translators: this is a menu category */
+	{ "learn", map_learn, N_("Learn"), "org.gnome.Software.Learn", 60 },
+	/* Translators: this is a menu category */
+	{ "develop", map_develop, N_("Develop"), "org.gnome.Software.Develop", 50 },
+
+	/* Translators: this is a menu category */
+	{ "codecs", map_addon_codecs, N_("Codecs"), NULL, 10 },
+	/* Translators: this is a menu category */
+	{ "drivers", map_addon_drivers, N_("Hardware Drivers"), NULL, 10 },
+	/* Translators: this is a menu category */
+	{ "fonts", map_addon_fonts, N_("Fonts"), NULL, 10 },
+	/* Translators: this is a menu category */
+	{ "input-sources", map_addon_input_sources, N_("Input Sources"), NULL, 10 },
+	/* Translators: this is a menu category */
+	{ "language-packs", map_addon_language_packs, N_("Language Packs"), NULL, 10 },
+	/* Translators: this is a menu category */
+	{ "localization", map_addon_localization, N_("Localization"), NULL, 10 },
+
+	{ NULL }
+};
+
+/* the -1 is for the NULL terminator */
+G_STATIC_ASSERT (G_N_ELEMENTS (msdata) - 1 == GS_DESKTOP_DATA_N_ENTRIES);
+
+const GsDesktopData *
+gs_desktop_get_data (void)
+{
+	return msdata;
+}
diff --git a/lib/gs-desktop-data.h b/lib/gs-desktop-data.h
new file mode 100644
index 0000000..049656a
--- /dev/null
+++ b/lib/gs-desktop-data.h
@@ -0,0 +1,43 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2011-2016 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib-object.h>
+
+G_BEGIN_DECLS
+
+typedef struct {
+	const gchar	*id;
+	const gchar	*name;
+	const gchar	*fdo_cats[16];
+} GsDesktopMap;
+
+typedef struct {
+	const gchar	*id;
+	const GsDesktopMap *mapping;
+	const gchar	*name;
+	const gchar	*icon;
+	gint		 score;
+} GsDesktopData;
+
+const GsDesktopData	*gs_desktop_get_data		(void);
+
+/**
+ * GS_DESKTOP_DATA_N_ENTRIES:
+ *
+ * Number of entries in the array returned by gs_desktop_get_data(). This is
+ * static and guaranteed to be up to date. It’s intended to be used when
+ * defining static arrays which need to be the same size as the array returned
+ * by gs_desktop_get_data().
+ *
+ * Since: 40
+ */
+#define GS_DESKTOP_DATA_N_ENTRIES 12
+
+G_END_DECLS
diff --git a/lib/gs-download-utils.c b/lib/gs-download-utils.c
new file mode 100644
index 0000000..4949064
--- /dev/null
+++ b/lib/gs-download-utils.c
@@ -0,0 +1,870 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021, 2022 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-download-utils
+ * @short_description: Download and HTTP utilities
+ *
+ * A set of utilities for downloading things and doing HTTP requests.
+ *
+ * Since: 42
+ */
+
+#include "config.h"
+
+#include <gio/gio.h>
+#include <glib.h>
+#include <glib-object.h>
+#include <glib/gi18n.h>
+#include <libsoup/soup.h>
+
+#include "gs-download-utils.h"
+#include "gs-utils.h"
+
+G_DEFINE_QUARK (gs-download-error-quark, gs_download_error)
+
+/**
+ * gs_build_soup_session:
+ *
+ * Build a new #SoupSession configured with the gnome-software user agent.
+ *
+ * A new #SoupSession should be used for each independent download context, such
+ * as in different plugins. Each #SoupSession caches HTTP connections and
+ * authentication information, and these likely needn’t be shared between
+ * plugins. Using separate sessions reduces thread contention.
+ *
+ * Returns: (transfer full): a new #SoupSession
+ * Since: 42
+ */
+SoupSession *
+gs_build_soup_session (void)
+{
+	return soup_session_new_with_options ("user-agent", gs_user_agent (),
+					      "timeout", 10,
+					      NULL);
+}
+
+/* See https://httpwg.org/specs/rfc7231.html#http.date
+ * For example: Sun, 06 Nov 1994 08:49:37 GMT */
+static gchar *
+date_time_to_rfc7231 (GDateTime *date_time)
+{
+#if SOUP_CHECK_VERSION(3, 0, 0)
+	return soup_date_time_to_string (date_time, SOUP_DATE_HTTP);
+#else
+	const gchar *day_names[] = { "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun" };
+	const gchar *month_names[] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
+
+	/* We can’t just use g_date_time_format() here because its output
+	 * (particularly day and month names) is locale-dependent.
+	 * #SoupDate is also a pain to use because there’s no easy way to
+	 * convert from a #GDateTime with libsoup-2.4, while preserving the timezone. */
+	g_autofree gchar *time_str = g_date_time_format (date_time, "%H:%M:%S %Z");
+
+	return g_strdup_printf ("%s, %02d %s %d %s",
+				day_names[g_date_time_get_day_of_week (date_time) - 1],
+				g_date_time_get_day_of_month (date_time),
+				month_names[g_date_time_get_month (date_time) - 1],
+				g_date_time_get_year (date_time),
+				time_str);
+#endif
+}
+
+static GDateTime *
+date_time_from_rfc7231 (const gchar *rfc7231_str)
+{
+#if SOUP_CHECK_VERSION(3, 0, 0)
+	return soup_date_time_new_from_http_string (rfc7231_str);
+#else
+	g_autoptr(SoupDate) soup_date = NULL;
+	g_autoptr(GTimeZone) tz = NULL;
+
+	soup_date = soup_date_new_from_string (rfc7231_str);
+	if (soup_date == NULL)
+		return NULL;
+
+	if (soup_date->utc)
+		tz = g_time_zone_new_utc ();
+	else
+		tz = g_time_zone_new_offset (soup_date->offset * 60);
+
+	return g_date_time_new (tz, soup_date->year, soup_date->month,
+				soup_date->day, soup_date->hour,
+				soup_date->minute, soup_date->second);
+#endif
+}
+
+typedef struct {
+	/* Input data. */
+	gchar *uri;  /* (not nullable) (owned) */
+	GInputStream *input_stream;  /* (nullable) (owned) */
+	GOutputStream *output_stream;  /* (nullable) (owned) */
+	gsize buffer_size_bytes;
+	gchar *last_etag;  /* (nullable) (owned) */
+	GDateTime *last_modified_date;  /* (nullable) (owned) */
+	int io_priority;
+	GsDownloadProgressCallback progress_callback;  /* (nullable) */
+	gpointer progress_user_data;
+
+	/* In-progress state. */
+	SoupMessage *message;  /* (nullable) (owned) */
+	gboolean close_input_stream;
+	gboolean close_output_stream;
+	gboolean discard_output_stream;
+	gsize total_read_bytes;
+	gsize total_written_bytes;
+	gsize expected_stream_size_bytes;
+	GBytes *currently_unwritten_chunk;  /* (nullable) (owned) */
+
+	/* Output data. */
+	gchar *new_etag;  /* (nullable) (owned) */
+	GDateTime *new_last_modified_date;  /* (nullable) (owned) */
+	GError *error;  /* (nullable) (owned) */
+} DownloadData;
+
+static void
+download_data_free (DownloadData *data)
+{
+	g_assert (data->input_stream == NULL || g_input_stream_is_closed (data->input_stream));
+	g_assert (data->output_stream == NULL || g_output_stream_is_closed (data->output_stream));
+
+	g_assert (data->currently_unwritten_chunk == NULL || data->error != NULL);
+
+	g_clear_object (&data->input_stream);
+	g_clear_object (&data->output_stream);
+
+	g_clear_pointer (&data->last_etag, g_free);
+	g_clear_pointer (&data->last_modified_date, g_date_time_unref);
+	g_clear_object (&data->message);
+	g_clear_pointer (&data->uri, g_free);
+	g_clear_pointer (&data->new_etag, g_free);
+	g_clear_pointer (&data->new_last_modified_date, g_date_time_unref);
+	g_clear_pointer (&data->currently_unwritten_chunk, g_bytes_unref);
+	g_clear_error (&data->error);
+
+	g_free (data);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (DownloadData, download_data_free)
+
+static void open_input_stream_cb (GObject      *source_object,
+                                  GAsyncResult *result,
+                                  gpointer      user_data);
+static void read_bytes_cb (GObject      *source_object,
+                           GAsyncResult *result,
+                           gpointer      user_data);
+static void write_bytes_cb (GObject      *source_object,
+                            GAsyncResult *result,
+                            gpointer      user_data);
+static void finish_download (GTask  *task,
+                             GError *error);
+static void close_stream_cb (GObject      *source_object,
+                             GAsyncResult *result,
+                             gpointer      user_data);
+static void download_progress (GTask *task);
+
+/**
+ * gs_download_stream_async:
+ * @soup_session: a #SoupSession
+ * @uri: (not nullable): the URI to download
+ * @output_stream: (not nullable): an output stream to write the download to
+ * @last_etag: (nullable): the last-known ETag of the URI, or %NULL if unknown
+ * @last_modified_date: (nullable): the last-known Last-Modified date of the
+ *   URI, or %NULL if unknown
+ * @io_priority: I/O priority to download and write at
+ * @progress_callback: (nullable): callback to call with progress information
+ * @progress_user_data: (nullable) (closure progress_callback): data to pass
+ *   to @progress_callback
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @callback: callback to call once the operation is complete
+ * @user_data: (closure callback): data to pass to @callback
+ *
+ * Download @uri and write it to @output_stream asynchronously.
+ *
+ * If @last_etag is non-%NULL or @last_modified_date is non-%NULL, they will be
+ * sent to the server, which may return a ‘not modified’ response. If so,
+ * @output_stream will not be written to, and will be closed with a cancelled
+ * close operation. This will ensure that the existing content of the output
+ * stream (if it’s a file, for example) will not be overwritten.
+ *
+ * Note that @last_etag must be the ETag value returned by the server last time
+ * the file was downloaded, not the local file ETag generated by GLib.
+ *
+ * If specified, @progress_callback will be called zero or more times until
+ * @callback is called, providing progress updates on the download.
+ *
+ * Since: 43
+ */
+void
+gs_download_stream_async (SoupSession                *soup_session,
+                          const gchar                *uri,
+                          GOutputStream              *output_stream,
+                          const gchar                *last_etag,
+                          GDateTime                  *last_modified_date,
+                          int                         io_priority,
+                          GsDownloadProgressCallback  progress_callback,
+                          gpointer                    progress_user_data,
+                          GCancellable               *cancellable,
+                          GAsyncReadyCallback         callback,
+                          gpointer                    user_data)
+{
+	g_autoptr(GTask) task = NULL;
+	g_autoptr(GError) local_error = NULL;
+	g_autoptr(SoupMessage) msg = NULL;
+	DownloadData *data;
+	g_autoptr(DownloadData) data_owned = NULL;
+
+	g_return_if_fail (SOUP_IS_SESSION (soup_session));
+	g_return_if_fail (uri != NULL);
+	g_return_if_fail (G_IS_OUTPUT_STREAM (output_stream));
+	g_return_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable));
+
+	task = g_task_new (soup_session, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_download_stream_async);
+
+	data = data_owned = g_new0 (DownloadData, 1);
+	data->uri = g_strdup (uri);
+	data->output_stream = g_object_ref (output_stream);
+	data->close_output_stream = TRUE;
+	data->buffer_size_bytes = 8192;  /* arbitrarily chosen */
+	data->io_priority = io_priority;
+	data->progress_callback = progress_callback;
+	data->progress_user_data = progress_user_data;
+
+	g_task_set_task_data (task, g_steal_pointer (&data_owned), (GDestroyNotify) download_data_free);
+
+	/* local */
+	if (g_str_has_prefix (uri, "file://")) {
+		g_autoptr(GFile) local_file = g_file_new_for_path (uri + strlen ("file://"));
+		g_file_read_async (local_file, io_priority, cancellable, open_input_stream_cb, g_steal_pointer (&task));
+		return;
+	}
+
+	/* remote */
+	g_debug ("Downloading %s to %s", uri, G_OBJECT_TYPE_NAME (output_stream));
+	msg = soup_message_new (SOUP_METHOD_GET, uri);
+	if (msg == NULL) {
+		finish_download (task,
+				 g_error_new (G_IO_ERROR,
+					      G_IO_ERROR_INVALID_ARGUMENT,
+					      "Failed to parse URI ‘%s’", uri));
+		return;
+	}
+
+	data->message = g_object_ref (msg);
+
+	/* Caching support. Prefer ETags to modification dates, as the latter
+	 * have problems with rapid updates and clock drift. */
+	if (last_etag != NULL && *last_etag == '\0')
+		last_etag = NULL;
+	data->last_etag = g_strdup (last_etag);
+
+	if (last_modified_date != NULL)
+		data->last_modified_date = g_date_time_ref (last_modified_date);
+
+	if (last_etag != NULL) {
+#if SOUP_CHECK_VERSION(3, 0, 0)
+		soup_message_headers_append (soup_message_get_request_headers (msg), "If-None-Match", last_etag);
+#else
+		soup_message_headers_append (msg->request_headers, "If-None-Match", last_etag);
+#endif
+	} else if (last_modified_date != NULL) {
+		g_autofree gchar *last_modified_date_str = date_time_to_rfc7231 (last_modified_date);
+#if SOUP_CHECK_VERSION(3, 0, 0)
+		soup_message_headers_append (soup_message_get_request_headers (msg), "If-Modified-Since", last_modified_date_str);
+#else
+		soup_message_headers_append (msg->request_headers, "If-Modified-Since", last_modified_date_str);
+#endif
+	}
+
+#if SOUP_CHECK_VERSION(3, 0, 0)
+	soup_session_send_async (soup_session, msg, data->io_priority, cancellable, open_input_stream_cb, g_steal_pointer (&task));
+#else
+	soup_session_send_async (soup_session, msg, cancellable, open_input_stream_cb, g_steal_pointer (&task));
+#endif
+}
+
+static void
+open_input_stream_cb (GObject      *source_object,
+                      GAsyncResult *result,
+                      gpointer      user_data)
+{
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	DownloadData *data = g_task_get_task_data (task);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+	g_autoptr(GInputStream) input_stream = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	/* This function can be called as a result of either reading a local
+	 * file, or sending an HTTP request, so @source_object’s type can vary. */
+	if (G_IS_FILE (source_object)) {
+		GFile *local_file = G_FILE (source_object);
+
+		/* Local file. */
+		input_stream = G_INPUT_STREAM (g_file_read_finish (local_file, result, &local_error));
+
+		if (input_stream == NULL) {
+			g_prefix_error (&local_error, "Failed to read ‘%s’: ",
+					g_file_peek_path (local_file));
+			finish_download (task, g_steal_pointer (&local_error));
+			return;
+		}
+
+		g_assert (data->input_stream == NULL);
+		data->input_stream = g_object_ref (input_stream);
+		data->close_input_stream = TRUE;
+	} else if (SOUP_IS_SESSION (source_object)) {
+		SoupSession *soup_session = SOUP_SESSION (source_object);
+		guint status_code;
+		const gchar *new_etag, *new_last_modified_str;
+
+		/* HTTP request. */
+#if SOUP_CHECK_VERSION(3, 0, 0)
+		input_stream = soup_session_send_finish (soup_session, result, &local_error);
+		status_code = soup_message_get_status (data->message);
+#else
+		input_stream = soup_session_send_finish (soup_session, result, &local_error);
+		status_code = data->message->status_code;
+#endif
+
+		if (input_stream != NULL) {
+			g_assert (data->input_stream == NULL);
+			data->input_stream = g_object_ref (input_stream);
+			data->close_input_stream = TRUE;
+		}
+
+		if (status_code == SOUP_STATUS_NOT_MODIFIED) {
+			/* If the file has not been modified from the ETag or
+			 * Last-Modified date we have, finish the download
+			 * early. Ensure to close the output stream so that its
+			 * existing content is *not* overwritten.
+			 *
+			 * Preserve the existing ETag. */
+			data->discard_output_stream = TRUE;
+			data->new_etag = g_strdup (data->last_etag);
+			data->new_last_modified_date = (data->last_modified_date != NULL) ? g_date_time_ref (data->last_modified_date) : NULL;
+			finish_download (task,
+					 g_error_new (GS_DOWNLOAD_ERROR,
+						      GS_DOWNLOAD_ERROR_NOT_MODIFIED,
+						      "Skipped downloading ‘%s’: %s",
+						      data->uri, soup_status_get_phrase (status_code)));
+			return;
+		} else if (status_code != SOUP_STATUS_OK) {
+			g_autoptr(GString) str = g_string_new (NULL);
+			g_string_append (str, soup_status_get_phrase (status_code));
+
+			if (local_error != NULL) {
+				g_string_append (str, ": ");
+				g_string_append (str, local_error->message);
+			}
+
+			finish_download (task,
+					 g_error_new (G_IO_ERROR,
+						      G_IO_ERROR_FAILED,
+						      "Failed to download ‘%s’: %s",
+						      data->uri, str->str));
+			return;
+		}
+
+		g_assert (input_stream != NULL);
+
+		/* Get the expected download size. */
+#if SOUP_CHECK_VERSION(3, 0, 0)
+		data->expected_stream_size_bytes = soup_message_headers_get_content_length (soup_message_get_response_headers (data->message));
+#else
+		data->expected_stream_size_bytes = soup_message_headers_get_content_length (data->message->response_headers);
+#endif
+
+		/* Store the new ETag for later use. */
+#if SOUP_CHECK_VERSION(3, 0, 0)
+		new_etag = soup_message_headers_get_one (soup_message_get_response_headers (data->message), "ETag");
+#else
+		new_etag = soup_message_headers_get_one (data->message->response_headers, "ETag");
+#endif
+		if (new_etag != NULL && *new_etag == '\0')
+			new_etag = NULL;
+		data->new_etag = g_strdup (new_etag);
+
+		/* Store the Last-Modified date for later use. */
+#if SOUP_CHECK_VERSION(3, 0, 0)
+		new_last_modified_str = soup_message_headers_get_one (soup_message_get_response_headers (data->message), "Last-Modified");
+#else
+		new_last_modified_str = soup_message_headers_get_one (data->message->response_headers, "Last-Modified");
+#endif
+		if (new_last_modified_str != NULL && *new_last_modified_str == '\0')
+			new_last_modified_str = NULL;
+		if (new_last_modified_str != NULL)
+			data->new_last_modified_date = date_time_from_rfc7231 (new_last_modified_str);
+	} else {
+		g_assert_not_reached ();
+	}
+
+	/* Splice in an asynchronous loop. We unfortunately can’t use
+	 * g_output_stream_splice_async() here, as it doesn’t provide a progress
+	 * callback. The approach is the same though. */
+	g_input_stream_read_bytes_async (input_stream, data->buffer_size_bytes, data->io_priority,
+					 cancellable, read_bytes_cb, g_steal_pointer (&task));
+}
+
+static void
+read_bytes_cb (GObject      *source_object,
+               GAsyncResult *result,
+               gpointer      user_data)
+{
+	GInputStream *input_stream = G_INPUT_STREAM (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	DownloadData *data = g_task_get_task_data (task);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+	g_autoptr(GBytes) bytes = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	bytes = g_input_stream_read_bytes_finish (input_stream, result, &local_error);
+
+	if (bytes == NULL) {
+		finish_download (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	/* Report progress. */
+	data->total_read_bytes += g_bytes_get_size (bytes);
+	data->expected_stream_size_bytes = MAX (data->expected_stream_size_bytes, data->total_read_bytes);
+	download_progress (task);
+
+	/* Write the downloaded data. */
+	if (g_bytes_get_size (bytes) > 0) {
+		g_clear_pointer (&data->currently_unwritten_chunk, g_bytes_unref);
+		data->currently_unwritten_chunk = g_bytes_ref (bytes);
+
+		g_output_stream_write_bytes_async (data->output_stream, bytes, data->io_priority,
+						   cancellable, write_bytes_cb, g_steal_pointer (&task));
+	} else {
+		finish_download (task, NULL);
+	}
+}
+
+static void
+write_bytes_cb (GObject      *source_object,
+                GAsyncResult *result,
+                gpointer      user_data)
+{
+	GOutputStream *output_stream = G_OUTPUT_STREAM (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	DownloadData *data = g_task_get_task_data (task);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+	gssize bytes_written_signed;
+	gsize bytes_written;
+	g_autoptr(GError) local_error = NULL;
+
+	bytes_written_signed = g_output_stream_write_bytes_finish (output_stream, result, &local_error);
+
+	if (bytes_written_signed < 0) {
+		finish_download (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	/* We know this is non-negative now. */
+	bytes_written = (gsize) bytes_written_signed;
+
+	/* Report progress. */
+	data->total_written_bytes += bytes_written;
+	download_progress (task);
+
+	g_assert (data->currently_unwritten_chunk != NULL);
+
+	if (bytes_written < g_bytes_get_size (data->currently_unwritten_chunk)) {
+		/* Partial write; try again with the remaining bytes. */
+		g_autoptr(GBytes) sub_bytes = g_bytes_new_from_bytes (data->currently_unwritten_chunk, bytes_written, g_bytes_get_size (data->currently_unwritten_chunk) - bytes_written);
+		g_assert (bytes_written > 0);
+
+		g_clear_pointer (&data->currently_unwritten_chunk, g_bytes_unref);
+		data->currently_unwritten_chunk = g_bytes_ref (sub_bytes);
+
+		g_output_stream_write_bytes_async (output_stream, sub_bytes, data->io_priority,
+						   cancellable, write_bytes_cb, g_steal_pointer (&task));
+	} else {
+		/* Full write succeeded. Start the next read. */
+		g_clear_pointer (&data->currently_unwritten_chunk, g_bytes_unref);
+
+		g_input_stream_read_bytes_async (data->input_stream, data->buffer_size_bytes, data->io_priority,
+						 cancellable, read_bytes_cb, g_steal_pointer (&task));
+	}
+}
+
+static inline gboolean
+is_not_modidifed_error (GError *error)
+{
+	return g_error_matches (error, GS_DOWNLOAD_ERROR, GS_DOWNLOAD_ERROR_NOT_MODIFIED);
+}
+
+/* error is (transfer full) */
+static void
+finish_download (GTask  *task,
+                 GError *error)
+{
+	DownloadData *data = g_task_get_task_data (task);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+
+	/* Final progress update. */
+	if (error == NULL || is_not_modidifed_error (error)) {
+		data->expected_stream_size_bytes = data->total_read_bytes;
+		download_progress (task);
+	}
+
+	/* Record the error from the operation, if set. */
+	g_assert (data->error == NULL);
+	data->error = g_steal_pointer (&error);
+
+	g_assert (!data->discard_output_stream || data->close_output_stream);
+
+	if (data->close_output_stream) {
+		g_autoptr(GCancellable) output_cancellable = NULL;
+
+		g_assert (data->output_stream != NULL);
+
+		/* If there’s been a prior error, or we are aborting writing the
+		 * output stream (perhaps because of a cache hit), close the
+		 * output stream but cancel the close operation so that the old
+		 * output file is not overwritten. */
+		if ((data->error != NULL && !is_not_modidifed_error (data->error)) || data->discard_output_stream) {
+			output_cancellable = g_cancellable_new ();
+			g_cancellable_cancel (output_cancellable);
+		} else if (g_task_get_cancellable (task) != NULL) {
+			output_cancellable = g_object_ref (g_task_get_cancellable (task));
+		}
+
+		g_output_stream_close_async (data->output_stream, data->io_priority, output_cancellable, close_stream_cb, g_object_ref (task));
+	}
+
+	if (data->close_input_stream && data->input_stream != NULL) {
+		g_input_stream_close_async (data->input_stream, data->io_priority, cancellable, close_stream_cb, g_object_ref (task));
+	}
+
+	/* Check in case both streams are already closed. */
+	close_stream_cb (NULL, NULL, g_object_ref (task));
+}
+
+static void
+close_stream_cb (GObject      *source_object,
+                 GAsyncResult *result,
+                 gpointer      user_data)
+{
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	DownloadData *data = g_task_get_task_data (task);
+	g_autoptr(GError) local_error = NULL;
+
+	if (G_IS_INPUT_STREAM (source_object)) {
+		/* Errors in closing the input stream are not fatal. */
+		if (!g_input_stream_close_finish (G_INPUT_STREAM (source_object),
+						  result, &local_error))
+			g_debug ("Error closing input stream: %s", local_error->message);
+		g_clear_error (&local_error);
+
+		data->close_input_stream = FALSE;
+	} else if (G_IS_OUTPUT_STREAM (source_object)) {
+		/* Errors in closing the output stream are fatal, but don’t
+		 * overwrite errors set earlier in the operation. */
+		if (!g_output_stream_close_finish (G_OUTPUT_STREAM (source_object),
+						   result, &local_error)) {
+			/* If we are aborting writing the output stream (perhaps
+			 * because of a cache hit), don’t report the error at
+			 * all. */
+			if (data->discard_output_stream &&
+			    g_error_matches (local_error, G_IO_ERROR, G_IO_ERROR_CANCELLED))
+				g_clear_error (&local_error);
+			else if (data->error == NULL)
+				data->error = g_steal_pointer (&local_error);
+			else if (!g_error_matches (local_error, G_IO_ERROR, G_IO_ERROR_CANCELLED))
+				g_debug ("Error closing output stream: %s", local_error->message);
+		}
+		g_clear_error (&local_error);
+
+		data->close_output_stream = FALSE;
+		data->discard_output_stream = FALSE;
+	} else {
+		/* finish_download() calls this with a NULL source_object */
+	}
+
+	/* Still waiting for one of the streams to close? */
+	if (data->close_input_stream || data->close_output_stream)
+		return;
+
+	if (data->error != NULL) {
+		g_task_return_error (task, g_error_copy (data->error));
+	} else {
+		g_task_return_boolean (task, TRUE);
+	}
+}
+
+static void
+download_progress (GTask *task)
+{
+	DownloadData *data = g_task_get_task_data (task);
+
+	if (data->progress_callback != NULL) {
+		/* This should be guaranteed by the rest of the download code. */
+		g_assert (data->expected_stream_size_bytes >= data->total_written_bytes);
+
+		data->progress_callback (data->total_written_bytes, data->expected_stream_size_bytes,
+					 data->progress_user_data);
+	}
+}
+
+/**
+ * gs_download_stream_finish:
+ * @soup_session: a #SoupSession
+ * @result: result of the asynchronous operation
+ * @new_etag_out: (out callee-allocates) (transfer full) (optional) (nullable):
+ *   return location for the ETag of the downloaded file (which may be %NULL),
+ *   or %NULL to ignore it
+ * @new_last_modified_date_out: (out callee-allocates) (transfer full) (optional) (nullable):
+ *   return location for the new Last-Modified date of the downloaded file
+ *   (which may be %NULL), or %NULL to ignore it
+ * @error: return location for a #GError
+ *
+ * Finish an asynchronous download operation started with
+ * gs_download_stream_async().
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 43
+ */
+gboolean
+gs_download_stream_finish (SoupSession   *soup_session,
+                           GAsyncResult  *result,
+                           gchar        **new_etag_out,
+                           GDateTime    **new_last_modified_date_out,
+                           GError       **error)
+{
+	DownloadData *data;
+
+	g_return_val_if_fail (g_task_is_valid (result, soup_session), FALSE);
+	g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gs_download_stream_async, FALSE);
+	g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
+
+	data = g_task_get_task_data (G_TASK (result));
+
+	if (new_etag_out != NULL)
+		*new_etag_out = g_strdup (data->new_etag);
+	if (new_last_modified_date_out != NULL)
+		*new_last_modified_date_out = (data->new_last_modified_date != NULL) ? g_date_time_ref (data->new_last_modified_date) : NULL;
+
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+typedef struct {
+	/* Input data. */
+	gchar *uri;  /* (not nullable) (owned) */
+	GFile *output_file;  /* (not nullable) (owned) */
+	int io_priority;
+	GsDownloadProgressCallback progress_callback;
+	gpointer progress_user_data;
+
+	/* In-progress data. */
+	gchar *last_etag;  /* (nullable) (owned) */
+	GDateTime *last_modified_date;  /* (nullable) (owned) */
+} DownloadFileData;
+
+static void
+download_file_data_free (DownloadFileData *data)
+{
+	g_free (data->uri);
+	g_clear_object (&data->output_file);
+	g_free (data->last_etag);
+	g_clear_pointer (&data->last_modified_date, g_date_time_unref);
+	g_free (data);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (DownloadFileData, download_file_data_free)
+
+static void download_replace_file_cb (GObject      *source_object,
+                                      GAsyncResult *result,
+                                      gpointer      user_data);
+static void download_file_cb (GObject      *source_object,
+                              GAsyncResult *result,
+                              gpointer      user_data);
+
+/**
+ * gs_download_file_async:
+ * @soup_session: a #SoupSession
+ * @uri: (not nullable): the URI to download
+ * @output_file: (not nullable): an output file to write the download to
+ * @io_priority: I/O priority to download and write at
+ * @progress_callback: (nullable): callback to call with progress information
+ * @progress_user_data: (nullable) (closure progress_callback): data to pass
+ *   to @progress_callback
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @callback: callback to call once the operation is complete
+ * @user_data: (closure callback): data to pass to @callback
+ *
+ * Download @uri and write it to @output_file asynchronously, overwriting the
+ * existing content of @output_file.
+ *
+ * The ETag and modification time of @output_file will be queried and, if known,
+ * used to skip the download if @output_file is already up to date.
+ *
+ * If specified, @progress_callback will be called zero or more times until
+ * @callback is called, providing progress updates on the download.
+ *
+ * Since: 42
+ */
+void
+gs_download_file_async (SoupSession                *soup_session,
+                        const gchar                *uri,
+                        GFile                      *output_file,
+                        int                         io_priority,
+                        GsDownloadProgressCallback  progress_callback,
+                        gpointer                    progress_user_data,
+                        GCancellable               *cancellable,
+                        GAsyncReadyCallback         callback,
+                        gpointer                    user_data)
+{
+	g_autoptr(GTask) task = NULL;
+	DownloadFileData *data;
+	g_autoptr(DownloadFileData) data_owned = NULL;
+	g_autoptr(GFile) output_file_parent = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	g_return_if_fail (SOUP_IS_SESSION (soup_session));
+	g_return_if_fail (uri != NULL);
+	g_return_if_fail (G_IS_FILE (output_file));
+	g_return_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable));
+
+	task = g_task_new (soup_session, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_download_file_async);
+
+	data = data_owned = g_new0 (DownloadFileData, 1);
+	data->uri = g_strdup (uri);
+	data->output_file = g_object_ref (output_file);
+	data->io_priority = io_priority;
+	data->progress_callback = progress_callback;
+	data->progress_user_data = progress_user_data;
+	g_task_set_task_data (task, g_steal_pointer (&data_owned), (GDestroyNotify) download_file_data_free);
+
+	/* Create the destination file’s directory.
+	 * FIXME: This should be made async; it hasn’t done for now as it’s
+	 * likely to be fast. */
+	output_file_parent = g_file_get_parent (output_file);
+
+	if (output_file_parent != NULL &&
+	    !g_file_make_directory_with_parents (output_file_parent, cancellable, &local_error) &&
+	    !g_error_matches (local_error, G_IO_ERROR, G_IO_ERROR_EXISTS)) {
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	g_clear_error (&local_error);
+
+	/* Query the old ETag and modification date if the file already exists. */
+	data->last_etag = gs_utils_get_file_etag (output_file, &data->last_modified_date, cancellable);
+
+	/* Create the output file.
+	 *
+	 * Note that `data->last_etag` is *not* passed in here, as the ETag from
+	 * the server and the file modification ETag that GLib uses are
+	 * different things. For g_file_replace_async(), GLib always uses an
+	 * ETag it generates internally based on the file mtime (see
+	 * _g_local_file_info_create_etag()), which will never match what the
+	 * server returns in its ETag header.
+	 *
+	 * This is fine, as we are using the ETag to avoid an unnecessary HTTP
+	 * download if possible. We don’t care about tracking changes to the
+	 * file on disk. */
+	g_file_replace_async (output_file,
+			      NULL,  /* ETag */
+			      FALSE,  /* make_backup */
+			      G_FILE_CREATE_PRIVATE | G_FILE_CREATE_REPLACE_DESTINATION,
+			      io_priority,
+			      cancellable,
+			      download_replace_file_cb,
+			      g_steal_pointer (&task));
+}
+
+static void
+download_replace_file_cb (GObject      *source_object,
+                          GAsyncResult *result,
+                          gpointer      user_data)
+{
+	GFile *output_file = G_FILE (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	SoupSession *soup_session = g_task_get_source_object (task);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+	DownloadFileData *data = g_task_get_task_data (task);
+	g_autoptr(GFileOutputStream) output_stream = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	output_stream = g_file_replace_finish (output_file, result, &local_error);
+
+	if (output_stream == NULL) {
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	/* Do the download. */
+	gs_download_stream_async (soup_session, data->uri, G_OUTPUT_STREAM (output_stream),
+				  data->last_etag, data->last_modified_date, data->io_priority,
+				  data->progress_callback, data->progress_user_data,
+				  cancellable, download_file_cb, g_steal_pointer (&task));
+}
+
+static void
+download_file_cb (GObject      *source_object,
+                  GAsyncResult *result,
+                  gpointer      user_data)
+{
+	SoupSession *soup_session = SOUP_SESSION (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+	DownloadFileData *data = g_task_get_task_data (task);
+	g_autofree gchar *new_etag = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	if (!gs_download_stream_finish (soup_session, result, &new_etag, NULL, &local_error)) {
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	/* Update the stored HTTP ETag.
+	 *
+	 * Under the assumption that this code is only ever used for locally
+	 * cached copies of remote files (i.e. the local copies are never
+	 * modified except by downloading an updated version from the server),
+	 * it’s safe to use the local file modification date for Last-Modified,
+	 * and save having to update that explicitly. This is because the
+	 * modification time of the local file equals when gnome-software last
+	 * checked for updates to it — which is correct to send as the
+	 * If-Modified-Since the next time gnome-software checks for updates to
+	 * the file. */
+	gs_utils_set_file_etag (data->output_file, new_etag, cancellable);
+
+	g_task_return_boolean (task, TRUE);
+}
+
+/**
+ * gs_download_file_finish:
+ * @soup_session: a #SoupSession
+ * @result: result of the asynchronous operation
+ * @error: return location for a #GError
+ *
+ * Finish an asynchronous download operation started with
+ * gs_download_file_async().
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 42
+ */
+gboolean
+gs_download_file_finish (SoupSession   *soup_session,
+                         GAsyncResult  *result,
+                         GError       **error)
+{
+	g_return_val_if_fail (g_task_is_valid (result, soup_session), FALSE);
+	g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gs_download_file_async, FALSE);
+	g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
+
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
diff --git a/lib/gs-download-utils.h b/lib/gs-download-utils.h
new file mode 100644
index 0000000..cd9dd46
--- /dev/null
+++ b/lib/gs-download-utils.h
@@ -0,0 +1,88 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2022 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <glib-object.h>
+#include <gio/gio.h>
+#include <libsoup/soup.h>
+
+G_BEGIN_DECLS
+
+SoupSession *gs_build_soup_session (void);
+
+/**
+ * GsDownloadProgressCallback:
+ * @bytes_downloaded: number of bytes downloaded so far
+ * @total_download_size: the total size of the download, in bytes
+ * @user_data: data passed to the calling function
+ *
+ * A progress callback to indicate how far a download has progressed.
+ *
+ * @total_download_size may be zero (for example, at the start of the download),
+ * so implementations of this callback must be careful to avoid division by zero
+ * errors.
+ *
+ * @total_download_size is guaranteed to always be greater than or equal to
+ * @bytes_downloaded.
+ *
+ * Since: 42
+ */
+typedef void (*GsDownloadProgressCallback) (gsize    bytes_downloaded,
+                                            gsize    total_download_size,
+                                            gpointer user_data);
+
+/**
+ * GsExternalAppstreamError:
+ * @GS_DOWNLOAD_ERROR_NOT_MODIFIED: The ETag matches that of the server file.
+ *
+ * Error codes for download operations.
+ *
+ * Since: 44
+ */
+typedef enum {
+	GS_DOWNLOAD_ERROR_NOT_MODIFIED,
+} GsDownloadError;
+
+#define GS_DOWNLOAD_ERROR gs_download_error_quark ()
+GQuark		 gs_download_error_quark (void);
+
+void		gs_download_stream_async	(SoupSession                *soup_session,
+						 const gchar                *uri,
+						 GOutputStream              *output_stream,
+						 const gchar                *last_etag,
+						 GDateTime                  *last_modified_date,
+						 int                         io_priority,
+						 GsDownloadProgressCallback  progress_callback,
+						 gpointer                    progress_user_data,
+						 GCancellable               *cancellable,
+						 GAsyncReadyCallback         callback,
+						 gpointer                    user_data);
+gboolean	gs_download_stream_finish	(SoupSession   *soup_session,
+						 GAsyncResult  *result,
+						 gchar        **new_etag_out,
+						 GDateTime    **new_last_modified_date_out,
+						 GError       **error);
+
+void		gs_download_file_async		(SoupSession                *soup_session,
+						 const gchar                *uri,
+						 GFile                      *output_file,
+						 int                         io_priority,
+						 GsDownloadProgressCallback  progress_callback,
+						 gpointer                    progress_user_data,
+						 GCancellable               *cancellable,
+						 GAsyncReadyCallback         callback,
+						 gpointer                    user_data);
+gboolean	gs_download_file_finish		(SoupSession   *soup_session,
+						 GAsyncResult  *result,
+						 GError       **error);
+
+G_END_DECLS
diff --git a/lib/gs-external-appstream-utils.c b/lib/gs-external-appstream-utils.c
new file mode 100644
index 0000000..24ce3a8
--- /dev/null
+++ b/lib/gs-external-appstream-utils.c
@@ -0,0 +1,627 @@
+ /* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2018 Endless Mobile, Inc.
+ *
+ * Authors: Joaquim Rocha <jrocha@endlessm.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/*
+ * SECTION:gs-external-appstream-urls
+ * @short_description: Provides support for downloading external AppStream files.
+ *
+ * This downloads the set of configured external AppStream files, and caches
+ * them locally.
+ *
+ * According to the `external-appstream-system-wide` GSetting, the files will
+ * either be downloaded to a per-user cache, or to a system-wide cache. In the
+ * case of a system-wide cache, they are downloaded to a temporary file writable
+ * by the user, and then the suexec binary `gnome-software-install-appstream` is
+ * run to copy them to the system location.
+ *
+ * All the downloads are done in the default #GMainContext for the thread which
+ * calls gs_external_appstream_refresh_async(). They are done in parallel and
+ * the async refresh function will only complete once the last download is
+ * complete.
+ *
+ * Progress data is reported via a callback, and gives the total progress of all
+ * parallel downloads. Internally this is done by updating #ProgressTuple
+ * structs as each download progresses. A periodic timeout callback sums these
+ * and reports the total progress to the caller. That means that progress
+ * reports from gs_external_appstream_refresh_async() are done at a constant
+ * frequency.
+ *
+ * To test this code locally you will probably want to change your GSettings
+ * configuration to add some external AppStream URIs:
+ * ```
+ * gsettings set org.gnome.software external-appstream-urls '["https://example.com/appdata.xml.gz"]'
+ * ```
+ *
+ * When you are done with development, run the following command to use the real
+ * external AppStream list again:
+ * ```
+ * gsettings reset org.gnome.software external-appstream-urls
+ * ```
+ *
+ * Since: 42
+ */
+
+#include <errno.h>
+#include <glib.h>
+#include <glib/gi18n.h>
+#include <glib/gstdio.h>
+#include <libsoup/soup.h>
+
+#include "gs-external-appstream-utils.h"
+
+#define APPSTREAM_SYSTEM_DIR LOCALSTATEDIR "/cache/swcatalog/xml"
+
+G_DEFINE_QUARK (gs-external-appstream-error-quark, gs_external_appstream_error)
+
+gchar *
+gs_external_appstream_utils_get_file_cache_path (const gchar *file_name)
+{
+	g_autofree gchar *prefixed_file_name = g_strdup_printf (EXTERNAL_APPSTREAM_PREFIX "-%s",
+								file_name);
+	return g_build_filename (APPSTREAM_SYSTEM_DIR, prefixed_file_name, NULL);
+}
+
+/* To be able to delete old files, when the path changed */
+gchar *
+gs_external_appstream_utils_get_legacy_file_cache_path (const gchar *file_name)
+{
+	g_autofree gchar *prefixed_file_name = g_strdup_printf (EXTERNAL_APPSTREAM_PREFIX "-%s",
+								file_name);
+	return g_build_filename (LOCALSTATEDIR "/cache/app-info/xmls", prefixed_file_name, NULL);
+}
+
+const gchar *
+gs_external_appstream_utils_get_system_dir (void)
+{
+	return APPSTREAM_SYSTEM_DIR;
+}
+
+static gboolean
+gs_external_appstream_check (GFile   *appstream_file,
+                             guint64  cache_age_secs)
+{
+	guint64 appstream_file_age = gs_utils_get_file_age (appstream_file);
+	return appstream_file_age >= cache_age_secs;
+}
+
+static gboolean
+gs_external_appstream_install (const gchar   *appstream_file,
+                               GCancellable  *cancellable,
+                               GError       **error)
+{
+	g_autoptr(GSubprocess) subprocess = NULL;
+	const gchar *argv[] = { "pkexec",
+				LIBEXECDIR "/gnome-software-install-appstream",
+				appstream_file, NULL};
+	g_debug ("Installing the appstream file %s in the system",
+		 appstream_file);
+	subprocess = g_subprocess_newv (argv,
+					G_SUBPROCESS_FLAGS_STDOUT_PIPE |
+					G_SUBPROCESS_FLAGS_STDIN_PIPE, error);
+	if (subprocess == NULL)
+		return FALSE;
+	return g_subprocess_wait_check (subprocess, cancellable, error);
+}
+
+static void download_replace_file_cb (GObject      *source_object,
+				      GAsyncResult *result,
+				      gpointer      user_data);
+static void download_stream_cb (GObject      *source_object,
+                                GAsyncResult *result,
+                                gpointer      user_data);
+
+/* A tuple to store the last-received progress data for a single download.
+ * Each download (refresh_url_async()) has a pointer to the relevant
+ * #ProgressTuple for its download. These are stored in an array in #RefreshData
+ * and a timeout callback periodically sums them all and reports progress to the
+ * caller. */
+typedef struct {
+	gsize bytes_downloaded;
+	gsize total_download_size;
+} ProgressTuple;
+
+typedef struct {
+	/* Input data. */
+	gchar *url;  /* (not nullable) (owned) */
+	GTask *task;  /* (not nullable) (owned) */
+	GFile *output_file;  /* (not nullable) (owned) */
+	ProgressTuple *progress_tuple;  /* (not nullable) */
+	SoupSession *soup_session;  /* (not nullable) (owned) */
+	gboolean system_wide;
+
+	/* In-progress data. */
+	gchar *last_etag;  /* (nullable) (owned) */
+	GDateTime *last_modified_date;  /* (nullable) (owned) */
+} DownloadAppStreamData;
+
+static void
+download_appstream_data_free (DownloadAppStreamData *data)
+{
+	g_free (data->url);
+	g_clear_object (&data->task);
+	g_clear_object (&data->output_file);
+	g_clear_object (&data->soup_session);
+	g_free (data->last_etag);
+	g_clear_pointer (&data->last_modified_date, g_date_time_unref);
+	g_free (data);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (DownloadAppStreamData, download_appstream_data_free)
+
+static void
+refresh_url_progress_cb (gsize    bytes_downloaded,
+                         gsize    total_download_size,
+                         gpointer user_data)
+{
+	ProgressTuple *tuple = user_data;
+
+	tuple->bytes_downloaded = bytes_downloaded;
+	tuple->total_download_size = total_download_size;
+
+	/* The timeout callback in progress_cb() periodically sums these. No
+	 * need to notify of progress from here. */
+}
+
+static void
+refresh_url_async (GSettings           *settings,
+                   const gchar         *url,
+                   SoupSession         *soup_session,
+                   guint64              cache_age_secs,
+                   ProgressTuple       *progress_tuple,
+                   GCancellable        *cancellable,
+                   GAsyncReadyCallback  callback,
+                   gpointer             user_data)
+{
+	g_autoptr(GTask) task = NULL;
+	g_autofree gchar *basename = NULL;
+	g_autofree gchar *basename_url = g_path_get_basename (url);
+	/* make sure different uris with same basenames differ */
+	g_autofree gchar *hash = NULL;
+	g_autofree gchar *target_file_path = NULL;
+	g_autoptr(GFile) target_file = NULL;
+	g_autoptr(GFile) tmp_file_parent = NULL;
+	g_autoptr(GFile) tmp_file = NULL;
+	g_autoptr(GsApp) app_dl = gs_app_new ("external-appstream");
+	g_autoptr(GError) local_error = NULL;
+	DownloadAppStreamData *data;
+	gboolean system_wide;
+
+	task = g_task_new (NULL, cancellable, callback, user_data);
+	g_task_set_source_tag (task, refresh_url_async);
+
+	/* Calculate the basename of the target file. */
+	hash = g_compute_checksum_for_string (G_CHECKSUM_SHA1, url, -1);
+	if (hash == NULL) {
+		g_task_return_new_error (task,
+					 GS_EXTERNAL_APPSTREAM_ERROR,
+					 GS_EXTERNAL_APPSTREAM_ERROR_DOWNLOADING,
+					 "Failed to hash URI ‘%s’", url);
+		return;
+	}
+	basename = g_strdup_printf ("%s-%s", hash, basename_url);
+
+	/* Are we downloading for the user, or the system? */
+	system_wide = g_settings_get_boolean (settings, "external-appstream-system-wide");
+
+	/* Check cache file age. */
+	if (system_wide) {
+		target_file_path = gs_external_appstream_utils_get_file_cache_path (basename);
+	} else {
+		g_autofree gchar *legacy_file_path = NULL;
+
+		target_file_path = g_build_filename (g_get_user_data_dir (),
+						     "swcatalog",
+						     "xml",
+						     basename,
+						     NULL);
+
+		/* Delete an old file, from a legacy location */
+		legacy_file_path = g_build_filename (g_get_user_data_dir (),
+						     "app-info",
+						     "xmls",
+						     basename,
+						     NULL);
+
+		if (g_unlink (legacy_file_path) == -1) {
+			int errn = errno;
+			if (errn != ENOENT)
+				g_debug ("Failed to unlink '%s': %s", legacy_file_path, g_strerror (errn));
+
+		}
+	}
+
+	target_file = g_file_new_for_path (target_file_path);
+
+	if (!gs_external_appstream_check (target_file, cache_age_secs)) {
+		g_debug ("skipping updating external appstream file %s: "
+			 "cache age is older than file",
+			 target_file_path);
+		g_task_return_boolean (task, TRUE);
+		return;
+	}
+
+	/* If downloading system wide, write the download contents into a
+	 * temporary file that will be copied into the system location later. */
+	if (system_wide) {
+		g_autofree gchar *tmp_file_path = NULL;
+
+		tmp_file_path = gs_utils_get_cache_filename ("external-appstream",
+							     basename,
+							     GS_UTILS_CACHE_FLAG_WRITEABLE |
+							     GS_UTILS_CACHE_FLAG_CREATE_DIRECTORY,
+							     &local_error);
+		if (tmp_file_path == NULL) {
+			g_task_return_error (task, g_steal_pointer (&local_error));
+			return;
+		}
+
+		tmp_file = g_file_new_for_path (tmp_file_path);
+	} else {
+		tmp_file = g_object_ref (target_file);
+	}
+
+	gs_app_set_summary_missing (app_dl,
+				    /* TRANSLATORS: status text when downloading */
+				    _("Downloading extra metadata files…"));
+
+	data = g_new0 (DownloadAppStreamData, 1);
+	data->url = g_strdup (url);
+	data->task = g_object_ref (task);
+	data->output_file = g_object_ref (tmp_file);
+	data->progress_tuple = progress_tuple;
+	data->soup_session = g_object_ref (soup_session);
+	data->system_wide = system_wide;
+	g_task_set_task_data (task, data, (GDestroyNotify) download_appstream_data_free);
+
+	/* Create the destination file’s directory.
+	 * FIXME: This should be made async; it hasn’t done for now as it’s
+	 * likely to be fast. */
+	tmp_file_parent = g_file_get_parent (tmp_file);
+
+	if (tmp_file_parent != NULL &&
+	    !g_file_make_directory_with_parents (tmp_file_parent, cancellable, &local_error) &&
+	    !g_error_matches (local_error, G_IO_ERROR, G_IO_ERROR_EXISTS)) {
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	g_clear_error (&local_error);
+
+	/* Query the ETag and modification date of the target file, if the file already exists. For
+	 * system-wide installations, this is the ETag of the AppStream file installed system-wide.
+	 * For local installations, this is just the local output file. */
+	data->last_etag = gs_utils_get_file_etag (target_file, &data->last_modified_date, cancellable);
+	g_debug ("Queried ETag of file %s: %s", g_file_peek_path (target_file), data->last_etag);
+
+	/* Create the output file */
+	g_file_replace_async (tmp_file,
+			      NULL,  /* ETag */
+			      FALSE,  /* make_backup */
+			      G_FILE_CREATE_PRIVATE | G_FILE_CREATE_REPLACE_DESTINATION,
+			      G_PRIORITY_LOW,
+			      cancellable,
+			      download_replace_file_cb,
+			      g_steal_pointer (&task));
+}
+
+static void
+download_replace_file_cb (GObject      *source_object,
+                          GAsyncResult *result,
+                          gpointer      user_data)
+{
+	GFile *output_file = G_FILE (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+	DownloadAppStreamData *data = g_task_get_task_data (task);
+	g_autoptr(GFileOutputStream) output_stream = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	output_stream = g_file_replace_finish (output_file, result, &local_error);
+
+	if (output_stream == NULL) {
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	/* Do the download. */
+	gs_download_stream_async (data->soup_session,
+				  data->url,
+				  G_OUTPUT_STREAM (output_stream),
+				  data->last_etag,
+				  data->last_modified_date,
+				  G_PRIORITY_LOW,
+				  refresh_url_progress_cb,
+				  data->progress_tuple,
+				  cancellable,
+				  download_stream_cb,
+				  g_steal_pointer (&task));
+}
+
+static void
+download_stream_cb (GObject      *source_object,
+                    GAsyncResult *result,
+                    gpointer      user_data)
+{
+	SoupSession *soup_session = SOUP_SESSION (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+	DownloadAppStreamData *data = g_task_get_task_data (task);
+	g_autoptr(GError) local_error = NULL;
+	g_autofree gchar *new_etag = NULL;
+
+	if (!gs_download_stream_finish (soup_session, result, &new_etag, NULL, &local_error)) {
+		if (data->system_wide && g_error_matches (local_error, GS_DOWNLOAD_ERROR, GS_DOWNLOAD_ERROR_NOT_MODIFIED)) {
+			g_debug ("External AppStream file not modified, removing temporary download file %s",
+				 g_file_peek_path (data->output_file));
+
+			/* System-wide installs should delete the empty file created when preparing to
+			 * download the external AppStream file. */
+			g_file_delete_async (data->output_file, G_PRIORITY_LOW, NULL, NULL, NULL);
+			g_task_return_boolean (task, TRUE);
+		} else if (!g_network_monitor_get_network_available (g_network_monitor_get_default ())) {
+			g_task_return_new_error (task,
+						 GS_EXTERNAL_APPSTREAM_ERROR,
+						 GS_EXTERNAL_APPSTREAM_ERROR_NO_NETWORK,
+						 "External AppStream could not be downloaded due to being offline");
+		} else {
+			g_task_return_new_error (task,
+						 GS_EXTERNAL_APPSTREAM_ERROR,
+						 GS_EXTERNAL_APPSTREAM_ERROR_DOWNLOADING,
+						 "Server returned no data for external AppStream file: %s",
+						 local_error->message);
+		}
+		return;
+	}
+
+	g_debug ("Downloaded appstream file %s", g_file_peek_path (data->output_file));
+
+	gs_utils_set_file_etag (data->output_file, new_etag, cancellable);
+
+	if (data->system_wide) {
+		/* install file systemwide */
+		if (!gs_external_appstream_install (g_file_peek_path (data->output_file),
+						    cancellable,
+						    &local_error)) {
+			g_task_return_new_error (task,
+						 GS_EXTERNAL_APPSTREAM_ERROR,
+						 GS_EXTERNAL_APPSTREAM_ERROR_INSTALLING_ON_SYSTEM,
+						 "Error installing external AppStream file on system: %s", local_error->message);
+			return;
+		}
+		g_debug ("Installed appstream file %s", g_file_peek_path (data->output_file));
+	}
+
+	g_task_return_boolean (task, TRUE);
+}
+
+static gboolean
+refresh_url_finish (GAsyncResult  *result,
+                    GError       **error)
+{
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+static void refresh_cb (GObject      *source_object,
+                        GAsyncResult *result,
+                        gpointer      user_data);
+static gboolean progress_cb (gpointer user_data);
+static void finish_refresh_op (GTask  *task,
+                               GError *error);
+
+typedef struct {
+	/* Input data. */
+	guint64 cache_age_secs;
+
+	/* In-progress data. */
+	guint n_pending_ops;
+	GError *error;  /* (nullable) (owned) */
+	gsize n_appstream_urls;
+	GsDownloadProgressCallback progress_callback;  /* (nullable) */
+	gpointer progress_user_data;  /* (closure progress_callback) */
+	ProgressTuple *progress_tuples;  /* (array length=n_appstream_urls) (owned) */
+	GSource *progress_source;  /* (owned) */
+} RefreshData;
+
+static void
+refresh_data_free (RefreshData *data)
+{
+	g_assert (data->n_pending_ops == 0);
+
+	/* If this was set it should have been stolen for g_task_return_error()
+	 * by now. */
+	g_assert (data->error == NULL);
+
+	/* Similarly, progress reporting should have been stopped by now. */
+	g_assert (g_source_is_destroyed (data->progress_source));
+	g_source_unref (data->progress_source);
+
+	g_free (data->progress_tuples);
+
+	g_free (data);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (RefreshData, refresh_data_free)
+
+/**
+ * gs_external_appstream_refresh_async:
+ * @cache_age_secs: cache age, in seconds, as passed to #GsPluginClass.refresh_metadata_async()
+ * @progress_callback: (nullable): callback to call with progress information
+ * @progress_user_data: (nullable) (closure progress_callback): data to pass
+ *   to @progress_callback
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @callback: function call when the asynchronous operation is complete
+ * @user_data: data to pass to @callback
+ *
+ * Refresh any configured external appstream files, if the cache is too old.
+ *
+ * Since: 42
+ */
+void
+gs_external_appstream_refresh_async (guint64                     cache_age_secs,
+                                     GsDownloadProgressCallback  progress_callback,
+                                     gpointer                    progress_user_data,
+                                     GCancellable               *cancellable,
+                                     GAsyncReadyCallback         callback,
+                                     gpointer                    user_data)
+{
+	g_autoptr(GSettings) settings = NULL;
+	g_auto(GStrv) appstream_urls = NULL;
+	gsize n_appstream_urls;
+	g_autoptr(SoupSession) soup_session = NULL;
+	g_autoptr(GTask) task = NULL;
+	RefreshData *data;
+	g_autoptr(RefreshData) data_owned = NULL;
+
+	/* Chosen to allow a few UI updates per second without updating the
+	 * progress label so often it’s unreadable. */
+	const guint progress_update_period_ms = 300;
+
+	task = g_task_new (NULL, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_external_appstream_refresh_async);
+
+	settings = g_settings_new ("org.gnome.software");
+	soup_session = gs_build_soup_session ();
+	appstream_urls = g_settings_get_strv (settings,
+					      "external-appstream-urls");
+	n_appstream_urls = g_strv_length (appstream_urls);
+
+	data = data_owned = g_new0 (RefreshData, 1);
+	data->progress_callback = progress_callback;
+	data->progress_user_data = progress_user_data;
+	data->n_appstream_urls = n_appstream_urls;
+	data->progress_tuples = g_new0 (ProgressTuple, n_appstream_urls);
+	data->progress_source = g_timeout_source_new (progress_update_period_ms);
+	g_task_set_task_data (task, g_steal_pointer (&data_owned), (GDestroyNotify) refresh_data_free);
+
+	/* Set up the progress timeout. This periodically sums up the progress
+	 * tuples in `data->progress_tuples` and reports them to the calling
+	 * function via @progress_callback, giving an overall progress for all
+	 * the parallel operations. */
+	g_source_set_callback (data->progress_source, progress_cb, g_object_ref (task), g_object_unref);
+	g_source_attach (data->progress_source, g_main_context_get_thread_default ());
+
+	/* Refresh all the URIs in parallel. */
+	data->n_pending_ops = 1;
+
+	for (gsize i = 0; i < n_appstream_urls; i++) {
+		if (!g_str_has_prefix (appstream_urls[i], "https")) {
+			g_warning ("Not considering %s as an external "
+				   "appstream source: please use an https URL",
+				   appstream_urls[i]);
+			continue;
+		}
+
+		data->n_pending_ops++;
+		refresh_url_async (settings,
+				   appstream_urls[i],
+				   soup_session,
+				   cache_age_secs,
+				   &data->progress_tuples[i],
+				   cancellable,
+				   refresh_cb,
+				   g_object_ref (task));
+	}
+
+	finish_refresh_op (task, NULL);
+}
+
+static void
+refresh_cb (GObject      *source_object,
+            GAsyncResult *result,
+            gpointer      user_data)
+{
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	g_autoptr(GError) local_error = NULL;
+
+	refresh_url_finish (result, &local_error);
+	finish_refresh_op (task, g_steal_pointer (&local_error));
+}
+
+static gboolean
+progress_cb (gpointer user_data)
+{
+	GTask *task = G_TASK (user_data);
+	RefreshData *data = g_task_get_task_data (task);
+	gsize parallel_bytes_downloaded = 0, parallel_total_download_size = 0;
+
+	/* Sum up the progress numerator and denominator for all parallel
+	 * downloads. */
+	for (gsize i = 0; i < data->n_appstream_urls; i++) {
+		const ProgressTuple *progress_tuple = &data->progress_tuples[i];
+
+		if (!g_size_checked_add (&parallel_bytes_downloaded,
+					 parallel_bytes_downloaded,
+					 progress_tuple->bytes_downloaded))
+			parallel_bytes_downloaded = G_MAXSIZE;
+		if (!g_size_checked_add (&parallel_total_download_size,
+					 parallel_total_download_size,
+					 progress_tuple->total_download_size))
+			parallel_total_download_size = G_MAXSIZE;
+	}
+
+	/* Report progress to the calling function. */
+	if (data->progress_callback != NULL)
+		data->progress_callback (parallel_bytes_downloaded,
+					 parallel_total_download_size,
+					 data->progress_user_data);
+
+	return G_SOURCE_CONTINUE;
+}
+
+/* @error is (transfer full) if non-%NULL */
+static void
+finish_refresh_op (GTask  *task,
+                   GError *error)
+{
+	RefreshData *data = g_task_get_task_data (task);
+	g_autoptr(GError) error_owned = g_steal_pointer (&error);
+
+	if (data->error == NULL && error_owned != NULL)
+		data->error = g_steal_pointer (&error_owned);
+	else if (error_owned != NULL)
+		g_debug ("Additional error while refreshing external appstream: %s", error_owned->message);
+
+	g_assert (data->n_pending_ops > 0);
+	data->n_pending_ops--;
+
+	if (data->n_pending_ops > 0)
+		return;
+
+	/* Emit one final progress update, then stop any further ones. */
+	progress_cb (task);
+	g_source_destroy (data->progress_source);
+
+	/* All complete. */
+	if (data->error != NULL)
+		g_task_return_error (task, g_steal_pointer (&data->error));
+	else
+		g_task_return_boolean (task, TRUE);
+}
+
+/**
+ * gs_external_appstream_refresh_finish:
+ * @result: a #GAsyncResult
+ * @error: return location for a #GError, or %NULL
+ *
+ * Finish an asynchronous refresh operation started with
+ * gs_external_appstream_refresh_async().
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 42
+ */
+gboolean
+gs_external_appstream_refresh_finish (GAsyncResult  *result,
+                                      GError       **error)
+{
+	g_return_val_if_fail (g_task_is_valid (result, NULL), FALSE);
+	g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
+
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
diff --git a/lib/gs-external-appstream-utils.h b/lib/gs-external-appstream-utils.h
new file mode 100644
index 0000000..63e67f8
--- /dev/null
+++ b/lib/gs-external-appstream-utils.h
@@ -0,0 +1,50 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2018 Endless Mobile, Inc.
+ *
+ * Authors: Joaquim Rocha <jrocha@endlessm.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include "config.h"
+
+#include <glib.h>
+#include <gnome-software.h>
+
+#define EXTERNAL_APPSTREAM_PREFIX "org.gnome.Software"
+
+/**
+ * GsExternalAppstreamError:
+ * @GS_EXTERNAL_APPSTREAM_ERROR_DOWNLOADING: Error while downloading external appstream data.
+ * @GS_EXTERNAL_APPSTREAM_ERROR_NO_NETWORK: Offline or network unavailable.
+ * @GS_EXTERNAL_APPSTREAM_ERROR_INSTALLING_ON_SYSTEM: Error while installing an external AppStream file system-wide.
+ *
+ * Error codes for external appstream operations.
+ *
+ * Since: 42
+ */
+typedef enum {
+	GS_EXTERNAL_APPSTREAM_ERROR_DOWNLOADING,
+	GS_EXTERNAL_APPSTREAM_ERROR_NO_NETWORK,
+	GS_EXTERNAL_APPSTREAM_ERROR_INSTALLING_ON_SYSTEM,
+} GsExternalAppstreamError;
+
+#define GS_EXTERNAL_APPSTREAM_ERROR gs_external_appstream_error_quark ()
+GQuark		 gs_external_appstream_error_quark (void);
+
+const gchar	*gs_external_appstream_utils_get_system_dir (void);
+gchar		*gs_external_appstream_utils_get_file_cache_path (const gchar	*file_name);
+gchar		*gs_external_appstream_utils_get_legacy_file_cache_path (const gchar *file_name);
+
+void		 gs_external_appstream_refresh_async (guint64                     cache_age_secs,
+						      GsDownloadProgressCallback  progress_callback,
+						      gpointer                    progress_user_data,
+						      GCancellable               *cancellable,
+						      GAsyncReadyCallback         callback,
+						      gpointer                    user_data);
+gboolean	 gs_external_appstream_refresh_finish (GAsyncResult  *result,
+						       GError       **error);
diff --git a/lib/gs-fedora-third-party.c b/lib/gs-fedora-third-party.c
new file mode 100644
index 0000000..6afebc0
--- /dev/null
+++ b/lib/gs-fedora-third-party.c
@@ -0,0 +1,497 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Red Hat <www.redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <glib.h>
+#include <gio/gio.h>
+
+#include "gs-fedora-third-party.h"
+
+struct _GsFedoraThirdParty
+{
+	GObject		 parent_instance;
+	GMutex		 lock;
+	gchar		*executable;
+	GHashTable	*repos; /* gchar *name ~> gchar *packaging format */
+	gint64		 last_update;
+};
+
+G_DEFINE_TYPE (GsFedoraThirdParty, gs_fedora_third_party, G_TYPE_OBJECT)
+
+static GObject *
+gs_fedora_third_party_constructor (GType type,
+				   guint n_construct_properties,
+				   GObjectConstructParam *construct_properties)
+{
+	static GWeakRef singleton;
+	GObject *result;
+
+	result = g_weak_ref_get (&singleton);
+	if (result == NULL) {
+		result = G_OBJECT_CLASS (gs_fedora_third_party_parent_class)->constructor (type, n_construct_properties, construct_properties);
+
+		if (result)
+			g_weak_ref_set (&singleton, result);
+	}
+
+	return result;
+}
+
+static void
+gs_fedora_third_party_finalize (GObject *object)
+{
+	GsFedoraThirdParty *self = GS_FEDORA_THIRD_PARTY (object);
+
+	g_clear_pointer (&self->executable, g_free);
+	g_clear_pointer (&self->repos, g_hash_table_unref);
+	g_mutex_clear (&self->lock);
+
+	/* Chain up to parent's method. */
+	G_OBJECT_CLASS (gs_fedora_third_party_parent_class)->finalize (object);
+}
+
+static void
+gs_fedora_third_party_class_init (GsFedoraThirdPartyClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+	object_class->constructor = gs_fedora_third_party_constructor;
+	object_class->finalize = gs_fedora_third_party_finalize;
+}
+
+static void
+gs_fedora_third_party_init (GsFedoraThirdParty *self)
+{
+	g_mutex_init (&self->lock);
+}
+
+GsFedoraThirdParty *
+gs_fedora_third_party_new (void)
+{
+	return g_object_new (GS_TYPE_FEDORA_THIRD_PARTY, NULL);
+}
+
+static gboolean
+gs_fedora_third_party_ensure_executable_locked (GsFedoraThirdParty *self,
+						GError **error)
+{
+	if (self->executable == NULL)
+		self->executable = g_find_program_in_path ("fedora-third-party");
+
+	if (self->executable == NULL) {
+		g_set_error (error, G_IO_ERROR, G_IO_ERROR_NOT_FOUND, "File 'fedora-third-party' not found");
+		return FALSE;
+	}
+
+	return TRUE;
+}
+
+gboolean
+gs_fedora_third_party_is_available (GsFedoraThirdParty *self)
+{
+	gboolean res;
+
+	g_return_val_if_fail (GS_IS_FEDORA_THIRD_PARTY (self), FALSE);
+
+	g_mutex_lock (&self->lock);
+	res = gs_fedora_third_party_ensure_executable_locked (self, NULL);
+	g_mutex_unlock (&self->lock);
+
+	return res;
+}
+
+void
+gs_fedora_third_party_invalidate (GsFedoraThirdParty *self)
+{
+	g_return_if_fail (GS_IS_FEDORA_THIRD_PARTY (self));
+
+	g_mutex_lock (&self->lock);
+	g_clear_pointer (&self->executable, g_free);
+	g_clear_pointer (&self->repos, g_hash_table_unref);
+	self->last_update = 0;
+	g_mutex_unlock (&self->lock);
+}
+
+typedef struct _AsyncData
+{
+	gboolean enable;
+	gboolean config_only;
+} AsyncData;
+
+static AsyncData *
+async_data_new (gboolean enable,
+		gboolean config_only)
+{
+	AsyncData *async_data = g_slice_new0 (AsyncData);
+	async_data->enable = enable;
+	async_data->config_only = config_only;
+	return async_data;
+}
+
+static void
+async_data_free (gpointer ptr)
+{
+	AsyncData *async_data = ptr;
+	if (async_data != NULL)
+		g_slice_free (AsyncData, async_data);
+}
+
+static void
+gs_fedora_third_party_query_thread (GTask *task,
+				    gpointer source_object,
+				    gpointer task_data,
+				    GCancellable *cancellable)
+{
+	g_autoptr(GError) error = NULL;
+	GsFedoraThirdPartyState state;
+	if (gs_fedora_third_party_query_sync (GS_FEDORA_THIRD_PARTY (source_object), &state, cancellable, &error))
+		g_task_return_int (task, state);
+	else
+		g_task_return_error (task, g_steal_pointer (&error));
+}
+
+void
+gs_fedora_third_party_query (GsFedoraThirdParty *self,
+			     GCancellable *cancellable,
+			     GAsyncReadyCallback callback,
+			     gpointer user_data)
+{
+	g_autoptr(GTask) task = NULL;
+
+	g_return_if_fail (GS_IS_FEDORA_THIRD_PARTY (self));
+
+	task = g_task_new (self, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_fedora_third_party_query);
+	g_task_run_in_thread (task, gs_fedora_third_party_query_thread);
+}
+
+gboolean
+gs_fedora_third_party_query_finish (GsFedoraThirdParty *self,
+				    GAsyncResult *result,
+				    GsFedoraThirdPartyState *out_state,
+				    GError **error)
+{
+	GError *local_error = NULL;
+	GsFedoraThirdPartyState state = GS_FEDORA_THIRD_PARTY_STATE_UNKNOWN;
+
+	g_return_val_if_fail (GS_IS_FEDORA_THIRD_PARTY (self), FALSE);
+
+	state = g_task_propagate_int (G_TASK (result), &local_error);
+	if (local_error) {
+		g_propagate_error (error, local_error);
+		return FALSE;
+	}
+
+	if (out_state)
+		*out_state = state;
+
+	return TRUE;
+}
+
+gboolean
+gs_fedora_third_party_query_sync (GsFedoraThirdParty *self,
+				  GsFedoraThirdPartyState *out_state,
+				  GCancellable *cancellable,
+				  GError **error)
+{
+	const gchar *args[] = {
+		"", /* executable */
+		"query",
+		"--quiet",
+		NULL
+	};
+	gboolean success = FALSE;
+
+	g_return_val_if_fail (GS_IS_FEDORA_THIRD_PARTY (self), FALSE);
+
+	g_mutex_lock (&self->lock);
+	if (gs_fedora_third_party_ensure_executable_locked (self, error)) {
+		gint wait_status = -1;
+		args[0] = self->executable;
+		success = g_spawn_sync (NULL, (gchar **) args, NULL, G_SPAWN_SEARCH_PATH, NULL, NULL, NULL, NULL, &wait_status, error);
+		if (success) {
+			GsFedoraThirdPartyState state = GS_FEDORA_THIRD_PARTY_STATE_UNKNOWN;
+			/* See https://pagure.io/fedora-third-party/blob/main/f/doc/fedora-third-party.1.md */
+			switch (WEXITSTATUS (wait_status)) {
+			case 0:
+				state = GS_FEDORA_THIRD_PARTY_STATE_ENABLED;
+				break;
+			case 1:
+				state = GS_FEDORA_THIRD_PARTY_STATE_DISABLED;
+				break;
+			case 2:
+				state = GS_FEDORA_THIRD_PARTY_STATE_ASK;
+				break;
+			default:
+				break;
+			}
+			if (out_state)
+				*out_state = state;
+		}
+	}
+	g_mutex_unlock (&self->lock);
+
+	return success;
+}
+
+static void
+gs_fedora_third_party_switch_thread (GTask *task,
+				     gpointer source_object,
+				     gpointer task_data,
+				     GCancellable *cancellable)
+{
+	g_autoptr(GError) error = NULL;
+	AsyncData *async_data = task_data;
+	if (gs_fedora_third_party_switch_sync (GS_FEDORA_THIRD_PARTY (source_object), async_data->enable, async_data->config_only, cancellable, &error))
+		g_task_return_boolean (task, TRUE);
+	else
+		g_task_return_error (task, g_steal_pointer (&error));
+}
+
+void
+gs_fedora_third_party_switch (GsFedoraThirdParty *self,
+			      gboolean enable,
+			      gboolean config_only,
+			      GCancellable *cancellable,
+			      GAsyncReadyCallback callback,
+			      gpointer user_data)
+{
+	g_autoptr(GTask) task = NULL;
+
+	g_return_if_fail (GS_IS_FEDORA_THIRD_PARTY (self));
+
+	task = g_task_new (self, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_fedora_third_party_switch);
+	g_task_set_task_data (task, async_data_new (enable, config_only), async_data_free);
+	g_task_run_in_thread (task, gs_fedora_third_party_switch_thread);
+}
+
+gboolean
+gs_fedora_third_party_switch_finish (GsFedoraThirdParty *self,
+				     GAsyncResult *result,
+				     GError **error)
+{
+	g_return_val_if_fail (GS_IS_FEDORA_THIRD_PARTY (self), FALSE);
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+gboolean
+gs_fedora_third_party_switch_sync (GsFedoraThirdParty *self,
+				   gboolean enable,
+				   gboolean config_only,
+				   GCancellable *cancellable,
+				   GError **error)
+{
+	const gchar *args[] = {
+		"pkexec",
+		"", /* executable */
+		"", /* command */
+		"", /* config-only */
+		NULL
+	};
+	gboolean success = FALSE;
+
+	g_return_val_if_fail (GS_IS_FEDORA_THIRD_PARTY (self), FALSE);
+
+	g_mutex_lock (&self->lock);
+	if (gs_fedora_third_party_ensure_executable_locked (self, error)) {
+		gint wait_status = -1;
+		args[1] = self->executable;
+		args[2] = enable ? "enable" : "disable";
+		args[3] = config_only ? "--config-only" : NULL;
+		success = g_spawn_sync (NULL, (gchar **) args, NULL, G_SPAWN_SEARCH_PATH, NULL, NULL, NULL, NULL, &wait_status, error) &&
+			  g_spawn_check_wait_status (wait_status, error);
+	}
+	g_mutex_unlock (&self->lock);
+
+	return success;
+}
+
+static void
+gs_fedora_third_party_opt_out_thread (GTask *task,
+				      gpointer source_object,
+				      gpointer task_data,
+				      GCancellable *cancellable)
+{
+	g_autoptr(GError) error = NULL;
+	if (gs_fedora_third_party_opt_out_sync (GS_FEDORA_THIRD_PARTY (source_object), cancellable, &error))
+		g_task_return_boolean (task, TRUE);
+	else
+		g_task_return_error (task, g_steal_pointer (&error));
+}
+
+void
+gs_fedora_third_party_opt_out (GsFedoraThirdParty *self,
+			       GCancellable *cancellable,
+			       GAsyncReadyCallback callback,
+			       gpointer user_data)
+{
+	g_autoptr(GTask) task = NULL;
+
+	g_return_if_fail (GS_IS_FEDORA_THIRD_PARTY (self));
+
+	task = g_task_new (self, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_fedora_third_party_opt_out);
+	g_task_run_in_thread (task, gs_fedora_third_party_opt_out_thread);
+}
+
+gboolean
+gs_fedora_third_party_opt_out_finish (GsFedoraThirdParty *self,
+				      GAsyncResult *result,
+				      GError **error)
+{
+	g_return_val_if_fail (GS_IS_FEDORA_THIRD_PARTY (self), FALSE);
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+gboolean
+gs_fedora_third_party_opt_out_sync (GsFedoraThirdParty *self,
+				    GCancellable *cancellable,
+				    GError **error)
+{
+	/* fedora-third-party-opt-out is a single-purpose script that changes
+	 * the third-party status from unset => disabled. It exists to allow
+	 * a different pkexec configuration for opting-out and thus avoid
+	 * admin users needing to authenticate to opt-out.
+	 */
+	const gchar *args[] = {
+		"pkexec",
+		"/usr/lib/fedora-third-party/fedora-third-party-opt-out",
+		NULL
+	};
+	gboolean success = FALSE;
+
+	g_return_val_if_fail (GS_IS_FEDORA_THIRD_PARTY (self), FALSE);
+
+	g_mutex_lock (&self->lock);
+	if (gs_fedora_third_party_ensure_executable_locked (self, error)) {
+		gint wait_status = -1;
+		success = g_spawn_sync (NULL, (gchar **) args, NULL, G_SPAWN_SEARCH_PATH, NULL, NULL, NULL, NULL, &wait_status, error) &&
+			  g_spawn_check_wait_status (wait_status, error);
+	}
+	g_mutex_unlock (&self->lock);
+
+	return success;
+}
+
+static void
+gs_fedora_third_party_list_thread (GTask *task,
+				   gpointer source_object,
+				   gpointer task_data,
+				   GCancellable *cancellable)
+{
+	g_autoptr(GError) error = NULL;
+	g_autoptr(GHashTable) repos = NULL;
+	if (gs_fedora_third_party_list_sync (GS_FEDORA_THIRD_PARTY (source_object), &repos, cancellable, &error))
+		g_task_return_pointer (task, g_steal_pointer (&repos), (GDestroyNotify) g_hash_table_unref);
+	else
+		g_task_return_error (task, g_steal_pointer (&error));
+}
+
+void
+gs_fedora_third_party_list (GsFedoraThirdParty *self,
+			    GCancellable *cancellable,
+			    GAsyncReadyCallback callback,
+			    gpointer user_data)
+{
+	g_autoptr(GTask) task = NULL;
+
+	g_return_if_fail (GS_IS_FEDORA_THIRD_PARTY (self));
+
+	task = g_task_new (self, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_fedora_third_party_list);
+	g_task_run_in_thread (task, gs_fedora_third_party_list_thread);
+}
+
+gboolean
+gs_fedora_third_party_list_finish (GsFedoraThirdParty *self,
+				   GAsyncResult *result,
+				   GHashTable **out_repos, /* gchar *name ~> gchar *management_plugin */
+				   GError **error)
+{
+	g_autoptr(GHashTable) repos = NULL;
+	g_return_val_if_fail (GS_IS_FEDORA_THIRD_PARTY (self), FALSE);
+	repos = g_task_propagate_pointer (G_TASK (result), error);
+	if (repos == NULL)
+		return FALSE;
+	if (out_repos)
+		*out_repos = g_steal_pointer (&repos);
+	return TRUE;
+}
+
+gboolean
+gs_fedora_third_party_list_sync (GsFedoraThirdParty *self,
+				 GHashTable **out_repos, /* gchar *name ~> gchar *management_plugin */
+				 GCancellable *cancellable,
+				 GError **error)
+{
+	const gchar *args[] = {
+		"", /* executable */
+		"list",
+		"--csv",
+		"--columns=type,name",
+		NULL
+	};
+	gboolean success = FALSE;
+
+	g_return_val_if_fail (GS_IS_FEDORA_THIRD_PARTY (self), FALSE);
+
+	g_mutex_lock (&self->lock);
+	/* Auto-recheck only twice a day */
+	if (self->repos == NULL || (g_get_real_time () / G_USEC_PER_SEC) - self->last_update > 12 * 60 * 60) {
+		g_clear_pointer (&self->repos, g_hash_table_unref);
+		if (gs_fedora_third_party_ensure_executable_locked (self, error)) {
+			gint wait_status = -1;
+			g_autofree gchar *stdoutput = NULL;
+			args[0] = self->executable;
+			if (g_spawn_sync (NULL, (gchar **) args, NULL, G_SPAWN_DEFAULT, NULL, NULL, &stdoutput, NULL, &wait_status, error) &&
+			    g_spawn_check_wait_status (wait_status, error)) {
+				GHashTable *repos = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
+				g_auto(GStrv) lines = NULL;
+
+				lines = g_strsplit (stdoutput != NULL ? stdoutput : "", "\n", -1);
+
+				for (gsize ii = 0; lines != NULL && lines[ii]; ii++) {
+					g_auto(GStrv) tokens = g_strsplit (lines[ii], ",", 2);
+					if (tokens != NULL && tokens[0] != NULL && tokens[1] != NULL) {
+						const gchar *repo_type = tokens[0];
+						/* The 'dnf' means 'packagekit' here */
+						if (g_str_equal (repo_type, "dnf"))
+							repo_type = "packagekit";
+						/* Hash them by name, which cannot clash between types */
+						g_hash_table_insert (repos, g_strdup (tokens[1]), g_strdup (repo_type));
+					}
+				}
+
+				self->repos = repos;
+			}
+		}
+		self->last_update = g_get_real_time () / G_USEC_PER_SEC;
+	}
+	success = self->repos != NULL;
+	if (success && out_repos)
+		*out_repos = g_hash_table_ref (self->repos);
+	g_mutex_unlock (&self->lock);
+
+	return success;
+}
+
+gboolean
+gs_fedora_third_party_util_is_third_party_repo (GHashTable *third_party_repos,
+						const gchar *origin,
+						const gchar *management_plugin)
+{
+	const gchar *expected_management_plugin;
+
+	if (third_party_repos == NULL || origin == NULL)
+		return FALSE;
+
+	expected_management_plugin = g_hash_table_lookup (third_party_repos, origin);
+	if (expected_management_plugin == NULL)
+		return FALSE;
+
+	return g_strcmp0 (management_plugin, expected_management_plugin) == 0;
+}
diff --git a/lib/gs-fedora-third-party.h b/lib/gs-fedora-third-party.h
new file mode 100644
index 0000000..11a0144
--- /dev/null
+++ b/lib/gs-fedora-third-party.h
@@ -0,0 +1,93 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Red Hat <www.redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <gio/gio.h>
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_FEDORA_THIRD_PARTY (gs_fedora_third_party_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsFedoraThirdParty, gs_fedora_third_party, GS, FEDORA_THIRD_PARTY, GObject)
+
+typedef enum _GsFedoraThirdPartyState {
+	GS_FEDORA_THIRD_PARTY_STATE_UNKNOWN,
+	GS_FEDORA_THIRD_PARTY_STATE_ENABLED,
+	GS_FEDORA_THIRD_PARTY_STATE_DISABLED,
+	GS_FEDORA_THIRD_PARTY_STATE_ASK
+} GsFedoraThirdPartyState;
+
+GsFedoraThirdParty *
+		gs_fedora_third_party_new	(void);
+gboolean	gs_fedora_third_party_is_available
+						(GsFedoraThirdParty	*self);
+void		gs_fedora_third_party_invalidate(GsFedoraThirdParty	*self);
+void		gs_fedora_third_party_query	(GsFedoraThirdParty	*self,
+						 GCancellable		*cancellable,
+						 GAsyncReadyCallback	 callback,
+						 gpointer		 user_data);
+gboolean	gs_fedora_third_party_query_finish
+						(GsFedoraThirdParty	*self,
+						 GAsyncResult		*result,
+						 GsFedoraThirdPartyState *out_state,
+						 GError			**error);
+gboolean	gs_fedora_third_party_query_sync(GsFedoraThirdParty	*self,
+						 GsFedoraThirdPartyState *out_state,
+						 GCancellable		*cancellable,
+						 GError			**error);
+void		gs_fedora_third_party_switch	(GsFedoraThirdParty	*self,
+						 gboolean		 enable,
+						 gboolean		 config_only,
+						 GCancellable		*cancellable,
+						 GAsyncReadyCallback	 callback,
+						 gpointer		 user_data);
+gboolean	gs_fedora_third_party_switch_finish
+						(GsFedoraThirdParty	*self,
+						 GAsyncResult		*result,
+						 GError			**error);
+gboolean	gs_fedora_third_party_switch_sync
+						(GsFedoraThirdParty	*self,
+						 gboolean		 enable,
+						 gboolean		 config_only,
+						 GCancellable		*cancellable,
+						 GError			**error);
+void		gs_fedora_third_party_opt_out	(GsFedoraThirdParty	*self,
+						 GCancellable		*cancellable,
+						 GAsyncReadyCallback	 callback,
+						 gpointer		 user_data);
+gboolean	gs_fedora_third_party_opt_out_finish
+						(GsFedoraThirdParty	*self,
+						 GAsyncResult		*result,
+						 GError			**error);
+gboolean	gs_fedora_third_party_opt_out_sync
+						(GsFedoraThirdParty	*self,
+						 GCancellable		*cancellable,
+						 GError			**error);
+void		gs_fedora_third_party_list	(GsFedoraThirdParty	*self,
+						 GCancellable		*cancellable,
+						 GAsyncReadyCallback	 callback,
+						 gpointer		 user_data);
+gboolean	gs_fedora_third_party_list_finish
+						(GsFedoraThirdParty	*self,
+						 GAsyncResult		*result,
+						 GHashTable		**out_repos,
+						 GError			**error);
+gboolean	gs_fedora_third_party_list_sync	(GsFedoraThirdParty	*self,
+						 GHashTable		**out_repos,
+						 GCancellable		*cancellable,
+						 GError			**error);
+
+/* Utility functions */
+gboolean	gs_fedora_third_party_util_is_third_party_repo
+						(GHashTable		*third_party_repos,
+						 const gchar		*origin,
+						 const gchar		*management_plugin);
+
+G_END_DECLS
diff --git a/lib/gs-icon.c b/lib/gs-icon.c
new file mode 100644
index 0000000..955ab02
--- /dev/null
+++ b/lib/gs-icon.c
@@ -0,0 +1,315 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Endless OS Foundation, Inc
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-icon
+ * @short_description: Utilities for handling #GIcons
+ *
+ * This file provides several utilities for creating and handling #GIcon
+ * instances. #GIcon is used for representing icon sources throughout
+ * gnome-software, as it has low memory overheads, and allows the most
+ * appropriate icon data to be loaded when it’s needed to be used in a UI.
+ *
+ * gnome-software uses various classes which implement #GIcon, mostly the
+ * built-in ones provided by GIO, but also #GsRemoteIcon. All of them are tagged
+ * with `width` and `height` metadata (when that data was available at
+ * construction time). See gs_icon_get_width().
+ *
+ * Since: 40
+ */
+
+#include "config.h"
+
+#include <appstream.h>
+#include <gdk-pixbuf/gdk-pixbuf.h>
+#include <gio/gio.h>
+#include <glib.h>
+#include <glib-object.h>
+#include <gtk/gtk.h>
+
+#include "gs-icon.h"
+#include "gs-remote-icon.h"
+
+/**
+ * gs_icon_get_width:
+ * @icon: a #GIcon
+ *
+ * Get the width of an icon, if it was attached as metadata when the #GIcon was
+ * created from an #AsIcon.
+ *
+ * Returns: width of the icon (in device pixels), or `0` if unknown
+ * Since: 40
+ */
+guint
+gs_icon_get_width (GIcon *icon)
+{
+	g_return_val_if_fail (G_IS_ICON (icon), 0);
+
+	return GPOINTER_TO_UINT (g_object_get_data (G_OBJECT (icon), "width"));
+}
+
+/**
+ * gs_icon_set_width:
+ * @icon: a #GIcon
+ * @width: width of the icon, in device pixels
+ *
+ * Set the width of an icon. See gs_icon_get_width().
+ *
+ * Since: 40
+ */
+void
+gs_icon_set_width (GIcon *icon,
+                   guint  width)
+{
+	g_return_if_fail (G_IS_ICON (icon));
+
+	g_object_set_data (G_OBJECT (icon), "width", GUINT_TO_POINTER (width));
+}
+
+/**
+ * gs_icon_get_height:
+ * @icon: a #GIcon
+ *
+ * Get the height of an icon, if it was attached as metadata when the #GIcon was
+ * created from an #AsIcon.
+ *
+ * Returns: height of the icon (in device pixels), or `0` if unknown
+ * Since: 40
+ */
+guint
+gs_icon_get_height (GIcon *icon)
+{
+	g_return_val_if_fail (G_IS_ICON (icon), 0);
+
+	return GPOINTER_TO_UINT (g_object_get_data (G_OBJECT (icon), "height"));
+}
+
+/**
+ * gs_icon_set_height:
+ * @icon: a #GIcon
+ * @height: height of the icon, in device pixels
+ *
+ * Set the height of an icon. See gs_icon_get_height().
+ *
+ * Since: 40
+ */
+void
+gs_icon_set_height (GIcon *icon,
+                    guint  height)
+{
+	g_return_if_fail (G_IS_ICON (icon));
+
+	g_object_set_data (G_OBJECT (icon), "height", GUINT_TO_POINTER (height));
+}
+
+/**
+ * gs_icon_get_scale:
+ * @icon: a #GIcon
+ *
+ * Get the scale of an icon, if it was attached as metadata when the #GIcon was
+ * created from an #AsIcon.
+ *
+ * See gtk_widget_get_scale_factor() for more information about scales.
+ *
+ * Returns: scale of the icon, or `1` if unknown; guaranteed to always be
+ *     greater than or equal to 1
+ * Since: 40
+ */
+guint
+gs_icon_get_scale (GIcon *icon)
+{
+	g_return_val_if_fail (G_IS_ICON (icon), 0);
+
+	return MAX (1, GPOINTER_TO_UINT (g_object_get_data (G_OBJECT (icon), "scale")));
+}
+
+/**
+ * gs_icon_set_scale:
+ * @icon: a #GIcon
+ * @scale: scale of the icon, which must be greater than or equal to 1
+ *
+ * Set the scale of an icon. See gs_icon_get_scale().
+ *
+ * Since: 40
+ */
+void
+gs_icon_set_scale (GIcon *icon,
+                   guint  scale)
+{
+	g_return_if_fail (G_IS_ICON (icon));
+	g_return_if_fail (scale >= 1);
+
+	g_object_set_data (G_OBJECT (icon), "scale", GUINT_TO_POINTER (scale));
+}
+
+static GIcon *
+gs_icon_load_local (AsIcon *icon)
+{
+	const gchar *filename = as_icon_get_filename (icon);
+	g_autoptr(GFile) file = NULL;
+
+	if (filename == NULL)
+		return NULL;
+
+	file = g_file_new_for_path (filename);
+	return g_file_icon_new (file);
+}
+
+static GIcon *
+gs_icon_load_stock (AsIcon *icon)
+{
+	const gchar *name = as_icon_get_name (icon);
+
+	if (name == NULL)
+		return NULL;
+
+	return g_themed_icon_new (name);
+}
+
+static GIcon *
+gs_icon_load_remote (AsIcon *icon)
+{
+	const gchar *url = as_icon_get_url (icon);
+
+	if (url == NULL)
+		return NULL;
+
+	/* Load local files directly. */
+	if (g_str_has_prefix (url, "file:")) {
+		g_autoptr(GFile) file = g_file_new_for_path (url + strlen ("file:"));
+		return g_file_icon_new (file);
+	}
+
+	/* Only HTTP and HTTPS are supported. */
+	if (!g_str_has_prefix (url, "http:") &&
+	    !g_str_has_prefix (url, "https:"))
+		return NULL;
+
+	return gs_remote_icon_new (url);
+}
+
+static GIcon *
+gs_icon_load_cached (AsIcon *icon)
+{
+	const gchar *filename = as_icon_get_filename (icon);
+	const gchar *name = as_icon_get_name (icon);
+	g_autofree gchar *name_allocated = NULL;
+	g_autofree gchar *full_filename = NULL;
+	g_autoptr(GFile) file = NULL;
+
+	if (filename == NULL || name == NULL)
+		return NULL;
+
+	/* FIXME: Work around https://github.com/hughsie/appstream-glib/pull/390
+	 * where appstream files generated with appstream-builder from
+	 * appstream-glib, with its hidpi option enabled, will contain an
+	 * unnecessary size subdirectory in the icon name. */
+	if (g_str_has_prefix (name, "64x64/"))
+		name = name_allocated = g_strdup (name + strlen ("64x64/"));
+	else if (g_str_has_prefix (name, "128x128/"))
+		name = name_allocated = g_strdup (name + strlen ("128x128/"));
+
+	if (!g_str_has_suffix (filename, name)) {
+		/* Spec: https://www.freedesktop.org/software/appstream/docs/sect-AppStream-IconCache.html#spec-iconcache-location */
+		if (as_icon_get_scale (icon) <= 1) {
+			full_filename = g_strdup_printf ("%s/%ux%u/%s",
+							 filename,
+							 as_icon_get_width (icon),
+							 as_icon_get_height (icon),
+							 name);
+		} else {
+			full_filename = g_strdup_printf ("%s/%ux%u@%u/%s",
+							 filename,
+							 as_icon_get_width (icon),
+							 as_icon_get_height (icon),
+							 as_icon_get_scale (icon),
+							 name);
+		}
+
+		filename = full_filename;
+	}
+
+	file = g_file_new_for_path (filename);
+	return g_file_icon_new (file);
+}
+
+/**
+ * gs_icon_new_for_appstream_icon:
+ * @appstream_icon: an #AsIcon
+ *
+ * Create a new #GIcon representing the given #AsIcon. The actual type of the
+ * returned icon will vary depending on the #AsIconKind of @appstream_icon.
+ *
+ * If the width or height of the icon are set on the #AsIcon, they are stored
+ * as the `width` and `height` data associated with the returned object, using
+ * g_object_set_data().
+ *
+ * This can fail (and return %NULL) if the @appstream_icon has invalid or
+ * missing properties.
+ *
+ * Returns: (transfer full) (nullable): the #GIcon, or %NULL
+ * Since: 40
+ */
+GIcon *
+gs_icon_new_for_appstream_icon (AsIcon *appstream_icon)
+{
+	g_autoptr(GIcon) icon = NULL;
+
+	g_return_val_if_fail (AS_IS_ICON (appstream_icon), NULL);
+
+	switch (as_icon_get_kind (appstream_icon)) {
+	case AS_ICON_KIND_LOCAL:
+		icon = gs_icon_load_local (appstream_icon);
+		break;
+	case AS_ICON_KIND_STOCK:
+		icon = gs_icon_load_stock (appstream_icon);
+		break;
+	case AS_ICON_KIND_REMOTE:
+		icon = gs_icon_load_remote (appstream_icon);
+		break;
+	case AS_ICON_KIND_CACHED:
+		icon = gs_icon_load_cached (appstream_icon);
+		break;
+	default:
+		g_assert_not_reached ();
+	}
+
+	if (icon == NULL) {
+		g_debug ("Error creating GIcon for AsIcon of kind %s",
+			 as_icon_kind_to_string (as_icon_get_kind (appstream_icon)));
+		return NULL;
+	}
+
+	/* Store the width, height and scale as associated metadata (if
+	 * available) so that #GsApp can sort icons by size and return the most
+	 * appropriately sized one in gs_app_get_icon_by_size().
+	 *
+	 * FIXME: Ideally we’d store these as properties on the objects, but
+	 * GIO currently doesn’t allow subclassing of its #GIcon classes. If we
+	 * were to implement a #GLoadableIcon with these as properties, all the
+	 * fast paths in GTK for loading icon data (particularly named icons)
+	 * would be ignored.
+	 *
+	 * Storing the width and height as associated metadata means GObject
+	 * creates a hash table for each GIcon object. This is a waste of memory
+	 * (compared to using properties), but seems like the least-worst
+	 * option.
+	 *
+	 * See https://gitlab.gnome.org/GNOME/glib/-/issues/2345
+	 */
+	if (as_icon_get_width (appstream_icon) != 0 || as_icon_get_height (appstream_icon) != 0) {
+		gs_icon_set_width (icon, as_icon_get_width (appstream_icon));
+		gs_icon_set_height (icon, as_icon_get_height (appstream_icon));
+	}
+	if (as_icon_get_scale (appstream_icon) != 0)
+		gs_icon_set_scale (icon, as_icon_get_scale (appstream_icon));
+
+	return g_steal_pointer (&icon);
+}
diff --git a/lib/gs-icon.h b/lib/gs-icon.h
new file mode 100644
index 0000000..b1b7a89
--- /dev/null
+++ b/lib/gs-icon.h
@@ -0,0 +1,32 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Endless OS Foundation, Inc
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <appstream.h>
+#include <gio/gio.h>
+#include <glib.h>
+#include <glib-object.h>
+
+G_BEGIN_DECLS
+
+guint		 gs_icon_get_width			(GIcon			 *icon);
+void		 gs_icon_set_width			(GIcon			 *icon,
+							 guint			  width);
+guint		 gs_icon_get_height			(GIcon			 *icon);
+void		 gs_icon_set_height			(GIcon			 *icon,
+							 guint			  height);
+guint		 gs_icon_get_scale			(GIcon			 *icon);
+void		 gs_icon_set_scale			(GIcon			 *icon,
+							 guint			  scale);
+
+GIcon		*gs_icon_new_for_appstream_icon		(AsIcon			 *appstream_icon);
+
+G_END_DECLS
diff --git a/lib/gs-ioprio.c b/lib/gs-ioprio.c
new file mode 100644
index 0000000..3a63d07
--- /dev/null
+++ b/lib/gs-ioprio.c
@@ -0,0 +1,197 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2005, Novell, Inc.
+ * Copyright (C) 2006, Jamie McCracken <jamiemcc@gnome.org>
+ * Copyright (C) 2006, Anders Aagaard
+ *
+ * Based mostly on code by Robert Love <rml@novell.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include "config.h"
+
+#ifdef __linux__
+
+#include <stdio.h>
+#include <errno.h>
+
+#ifdef HAVE_LINUX_UNISTD_H
+#include <linux/unistd.h>
+#endif
+
+#include <sys/syscall.h>
+#include <unistd.h>
+
+#include <glib/gstdio.h>
+
+#endif /* __linux__ */
+
+#include "gs-ioprio.h"
+
+/* We assume ALL linux architectures have the syscalls defined here */
+#ifdef __linux__
+
+/* Make sure the system call is supported */
+#ifndef __NR_ioprio_set
+
+#if defined(__i386__)
+#define __NR_ioprio_set                 289
+#define __NR_ioprio_get                 290
+#elif defined(__powerpc__) || defined(__powerpc64__)
+#define __NR_ioprio_set                 273
+#define __NR_ioprio_get                 274
+#elif defined(__x86_64__)
+#define __NR_ioprio_set                 251
+#define __NR_ioprio_get                 252
+#elif defined(__ia64__)
+#define __NR_ioprio_set                 1274
+#define __NR_ioprio_get                 1275
+#elif defined(__alpha__)
+#define __NR_ioprio_set                 442
+#define __NR_ioprio_get                 443
+#elif defined(__s390x__) || defined(__s390__)
+#define __NR_ioprio_set                 282
+#define __NR_ioprio_get                 283
+#elif defined(__SH4__)
+#define __NR_ioprio_set                 288
+#define __NR_ioprio_get                 289
+#elif defined(__SH5__)
+#define __NR_ioprio_set                 316
+#define __NR_ioprio_get                 317
+#elif defined(__sparc__) || defined(__sparc64__)
+#define __NR_ioprio_set                 196
+#define __NR_ioprio_get                 218
+#elif defined(__arm__)
+#define __NR_ioprio_set                 314
+#define __NR_ioprio_get                 315
+#else
+#error "Unsupported architecture!"
+#endif
+
+#endif /* __NR_ioprio_set */
+
+enum {
+	IOPRIO_CLASS_NONE,
+	IOPRIO_CLASS_RT,
+	IOPRIO_CLASS_BE,
+	IOPRIO_CLASS_IDLE,
+};
+
+enum {
+	IOPRIO_WHO_PROCESS = 1,
+	IOPRIO_WHO_PGRP,
+	IOPRIO_WHO_USER,
+};
+
+#define IOPRIO_CLASS_SHIFT 13
+
+static inline int
+ioprio_set (int which, int who, int ioprio_val)
+{
+	return syscall (__NR_ioprio_set, which, who, ioprio_val);
+}
+
+static int
+set_io_priority (int ioprio,
+		 int ioclass)
+{
+	return ioprio_set (IOPRIO_WHO_PROCESS, 0, ioprio | (ioclass << IOPRIO_CLASS_SHIFT));
+}
+
+static const gchar *
+ioclass_to_string (int ioclass)
+{
+	switch (ioclass) {
+	case IOPRIO_CLASS_IDLE:
+		return "IDLE";
+	case IOPRIO_CLASS_BE:
+		return "BE";
+	default:
+		return "unknown";
+	}
+}
+
+/**
+ * gs_ioprio_set:
+ * @priority: I/O priority, with higher numeric values indicating lower priority;
+ *   use %G_PRIORITY_DEFAULT as the default
+ *
+ * Set the I/O priority of the current thread using the `ioprio_set()` syscall.
+ *
+ * The @priority is quantised before being passed to the kernel.
+ *
+ * This function may fail if the process doesn’t have permission to change its
+ * I/O priority to the given value. If so, a warning will be printed, as the
+ * quantised priority values are chosen so they shouldn’t typically require
+ * permissions to set.
+ */
+void
+gs_ioprio_set (gint priority)
+{
+	int ioprio, ioclass;
+
+	/* If the priority is lower than default, use an idle I/O priority. The
+	 * condition looks wrong because higher integers indicate lower priority
+	 * in GLib.
+	 *
+	 * Otherwise use a default best-effort priority, which is the same as
+	 * what all new threads get (in the absence of an I/O context with
+	 * `CLONE_IO`). */
+	if (priority > G_PRIORITY_DEFAULT) {
+		ioprio = 7;
+		ioclass = IOPRIO_CLASS_IDLE;
+	} else if (priority == G_PRIORITY_DEFAULT) {
+		ioprio = 4;  /* this is the default priority in the BE class */
+		ioclass = IOPRIO_CLASS_BE;
+	} else {
+		ioprio = 0;  /* this is the highest priority in the BE class */
+		ioclass = IOPRIO_CLASS_BE;
+	}
+
+	g_debug ("Setting I/O priority of thread %p to %s, %d",
+		 g_thread_self (), ioclass_to_string (ioclass), ioprio);
+
+	if (set_io_priority (ioprio, ioclass) == -1) {
+		g_warning ("Could not set I/O priority to %s, %d",
+			   ioclass_to_string (ioclass), ioprio);
+
+		/* If we were trying to set to idle priority, try again with the
+		 * lowest-possible best-effort priority. This is because kernels
+		 * older than 2.6.25 required `CAP_SYS_ADMIN` to set
+		 * `IOPRIO_CLASS_IDLE`. Newer kernels do not. */
+		if (ioclass == IOPRIO_CLASS_IDLE) {
+			ioprio = 7;  /* this is the lowest priority in the BE class */
+			ioclass = IOPRIO_CLASS_BE;
+
+			if (set_io_priority (ioprio, ioclass) == -1)
+				g_warning ("Could not set best effort IO priority either, giving up");
+		}
+	}
+}
+
+#else  /* __linux__ */
+
+void
+gs_ioprio_set (gint priority)
+{
+}
+
+#endif /* __linux__ */
diff --git a/lib/gs-ioprio.h b/lib/gs-ioprio.h
new file mode 100644
index 0000000..e630b8a
--- /dev/null
+++ b/lib/gs-ioprio.h
@@ -0,0 +1,31 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2006, Anders Aagaard
+ * Copyright (C) 2008, Nokia <ivan.frade@nokia.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA  02110-1301, USA.
+ */
+
+#pragma once
+
+#include <glib.h>
+
+G_BEGIN_DECLS
+
+void gs_ioprio_set (gint priority);
+
+G_END_DECLS
diff --git a/lib/gs-key-colors.c b/lib/gs-key-colors.c
new file mode 100644
index 0000000..fb0850c
--- /dev/null
+++ b/lib/gs-key-colors.c
@@ -0,0 +1,334 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2013-2016 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2013 Matthias Clasen <mclasen@redhat.com>
+ * Copyright (C) 2014-2018 Kalev Lember <klember@redhat.com>
+ * Copyright (C) 2021 Endless OS Foundation LLC
+ *
+ * Authors:
+ *  - Richard Hughes <richard@hughsie.com>
+ *  - Kalev Lember <klember@redhat.com>
+ *  - Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-key-colors
+ * @short_description: Helper functions for calculating key colors
+ *
+ * Key colors are RGB colors which represent an app, and they are derived from
+ * the app’s icon, or manually specified as an override.
+ *
+ * Use gs_calculate_key_colors() to calculate the key colors from an app’s icon.
+ *
+ * Since: 40
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <gdk/gdk.h>
+#include <gdk-pixbuf/gdk-pixbuf.h>
+
+#include "gs-key-colors.h"
+
+/* Hard-code the number of clusters to split the icon color space into. This
+ * gives the maximum number of key colors returned for an icon. This number has
+ * been chosen by examining 1000 icons to subjectively see how many key colors
+ * each has. The number of key colors ranged from 1 to 6, but the mode was
+ * definitely 3. */
+const guint n_clusters = 3;
+
+/* Discard pixels with less than this level of alpha. Almost all icons have a
+ * transparent background/border at 100% transparency, and a blending fringe
+ * with some intermediate level of transparency which should be ignored for
+ * choosing key colors. A number of icons have partially-transparent colored
+ * sections in the main body of the icon, which should be used if they’re above
+ * this threshold. About 1% of icons have no completely opaque pixels, so we
+ * can’t discard non-opaque pixels entirely. */
+const guint minimum_alpha = 0.5 * 255;
+
+typedef struct {
+	guint8 red;
+	guint8 green;
+	guint8 blue;
+} Pixel8;
+
+typedef struct {
+	Pixel8 color;
+	union {
+		guint8 alpha;
+		guint8 cluster;
+	};
+} ClusterPixel8;
+
+typedef struct {
+	guint red;
+	guint green;
+	guint blue;
+	guint n_members;
+} CentroidAccumulator;
+
+static inline ClusterPixel8 *
+get_pixel (guint8 *pixels,
+           guint   x,
+           guint   y,
+           guint   rowstride,
+           guint   n_channels)
+{
+	return (ClusterPixel8 *) (pixels + y * rowstride + x * n_channels);
+}
+
+static inline guint
+color_distance (const Pixel8 *a,
+                const Pixel8 *b)
+{
+	/* Take the absolute value rather than the square root to save some
+	 * time, as the caller is comparing distances.
+	 *
+	 * The arithmetic here can’t overflow, as the R/G/B components have a
+	 * maximum value of 255 but the arithmetic is done in (at least) 32-bit
+	 * variables.*/
+	gint dr = b->red - a->red;
+	gint dg = b->green - a->green;
+	gint db = b->blue - a->blue;
+
+	return abs (dr * dr + dg * dg + db * db);
+}
+
+/* NOTE: This has to return stable results when more than one cluster is
+ * equidistant from the @pixel, or the k_means() function may not terminate. */
+static inline gsize
+nearest_cluster (const Pixel8 *pixel,
+                 const Pixel8 *cluster_centres,
+                 gsize         n_cluster_centres)
+{
+	gsize nearest_cluster = 0;
+	guint nearest_cluster_distance = color_distance (&cluster_centres[0], pixel);
+
+	for (gsize i = 1; i < n_cluster_centres; i++) {
+		guint distance = color_distance (&cluster_centres[i], pixel);
+		if (distance < nearest_cluster_distance) {
+			nearest_cluster = i;
+			nearest_cluster_distance = distance;
+		}
+	}
+
+	return nearest_cluster;
+}
+
+/* A variant of g_random_int_range() which chooses without replacement,
+ * tracking the used integers in @used_ints and @n_used_ints.
+ * Once all integers in 0..max_ints have been used once, it will choose
+ * with replacement. */
+static gint32
+random_int_range_no_replacement (guint max_ints,
+				 gboolean *used_ints,
+				 guint *n_used_ints)
+{
+	gint32 random_value = g_random_int_range (0, (gint32) max_ints);
+
+	if (*n_used_ints < max_ints) {
+		while (used_ints[random_value])
+			random_value = (random_value + 1) % max_ints;
+
+		used_ints[random_value] = TRUE;
+		*n_used_ints = *n_used_ints + 1;
+	}
+
+	return random_value;
+}
+
+/* Extract the key colors from @pb by clustering the pixels in RGB space.
+ * Clustering is done using k-means, with initialisation using a
+ * Random Partition.
+ *
+ * This approach can be thought of as plotting every pixel in @pb in a
+ * three-dimensional color space, with red, green and blue axes (alpha is
+ * clipped to 0 (pixel is ignored) or 1 (pixel is used)). The key colors for
+ * the image are the ones where a large number of pixels are plotted in a group
+ * in the color space — either a lot of pixels with an identical color
+ * (repeated use of exactly the same color in the image) or a lot of pixels in
+ * a rough group (use of a lot of similar shades of the same color in the
+ * image).
+ *
+ * By transforming to a color space, information about the X and Y positions of
+ * each color is ignored, so a thin outline in the image of a single color
+ * will appear in the color space as a cluster, just as a contiguous block of
+ * one color would.
+ *
+ * The k-means clustering algorithm is then used to find these clusters. k-means
+ * is used, rather than (say) principal component analysis, because it
+ * inherently calculates the centroid for each cluster. In a color space, the
+ * centroid is itself a color, which can then be used as the key color to
+ * return.
+ *
+ * The number of clusters is limited to @n_clusters, as a subjective survey of
+ * 1000 icons found that they commonly used this number of key colors.
+ *
+ * Various other shortcuts have been taken which make this approach quite
+ * specific to key color extraction from icons, with the aim of making it
+ * faster. That’s fine — it doesn’t matter if the results this function produces
+ * are optimal, only that they’re good enough. */
+static void
+k_means (GArray    *colors,
+         GdkPixbuf *pb)
+{
+	gint rowstride, n_channels;
+	gint width, height;
+	guint8 *raw_pixels;
+	ClusterPixel8 *pixels;
+	const ClusterPixel8 *pixels_end;
+	Pixel8 cluster_centres[n_clusters];
+	CentroidAccumulator cluster_accumulators[n_clusters];
+	gboolean used_clusters[n_clusters];
+	guint n_used_clusters = 0;
+	guint n_assignments_changed;
+	guint n_iterations = 0;
+	guint assignments_termination_limit;
+
+	n_channels = gdk_pixbuf_get_n_channels (pb);
+	rowstride = gdk_pixbuf_get_rowstride (pb);
+	raw_pixels = gdk_pixbuf_get_pixels (pb);
+	width = gdk_pixbuf_get_width (pb);
+	height = gdk_pixbuf_get_height (pb);
+
+	/* The pointer arithmetic over pixels can be simplified if we can assume
+	 * there are no gaps in the @raw_pixels data. Since the caller is
+	 * downsizing the #GdkPixbuf, this is a reasonable assumption. */
+	g_assert (rowstride == width * n_channels);
+	g_assert (n_channels == 4);
+
+	pixels = (ClusterPixel8 *) raw_pixels;
+	pixels_end = &pixels[height * width];
+
+	memset (cluster_centres, 0, sizeof (cluster_centres));
+	memset (used_clusters, 0, sizeof (used_clusters));
+
+	/* Initialise the clusters using the Random Partition method: randomly
+	 * assign a starting cluster to each pixel.
+	 *
+	 * The Forgy method (choosing random pixels as the starting cluster
+	 * centroids) is not appropriate as the checks required to make sure
+	 * they aren’t transparent or duplicated colors mean that the
+	 * initialisation step may never complete. Consider the case of an icon
+	 * which is a block of solid color. */
+	for (ClusterPixel8 *p = pixels; p < pixels_end; p++) {
+		if (p->alpha < minimum_alpha)
+			p->cluster = G_N_ELEMENTS (cluster_centres);
+		else
+			p->cluster = random_int_range_no_replacement (G_N_ELEMENTS (cluster_centres), used_clusters, &n_used_clusters);
+	}
+
+	/* Iterate until every cluster is relatively settled. This is determined
+	 * by the number of pixels whose assignment to a cluster changes in
+	 * each iteration — if the number of pixels is less than 1% of the image
+	 * then subsequent iterations are not going to significantly affect the
+	 * results.
+	 *
+	 * As we’re choosing key colors, finding the optimal result is not
+	 * needed. We just need to find one which is good enough, quickly.
+	 *
+	 * A second termination condition is set on the number of iterations, to
+	 * avoid a potential infinite loop. This termination condition is never
+	 * normally expected to be hit — typically an icon will require 5–10
+	 * iterations to terminate based on @n_assignments_changed. */
+	assignments_termination_limit = width * height * 0.01;
+	n_iterations = 0;
+	do {
+		/* Update step. Re-calculate the centroid of each cluster from
+		 * the colors which are in it. */
+		memset (cluster_accumulators, 0, sizeof (cluster_accumulators));
+
+		for (const ClusterPixel8 *p = pixels; p < pixels_end; p++) {
+			if (p->cluster >= G_N_ELEMENTS (cluster_centres))
+				continue;
+
+			cluster_accumulators[p->cluster].red += p->color.red;
+			cluster_accumulators[p->cluster].green += p->color.green;
+			cluster_accumulators[p->cluster].blue += p->color.blue;
+			cluster_accumulators[p->cluster].n_members++;
+		}
+
+		for (gsize i = 0; i < G_N_ELEMENTS (cluster_centres); i++) {
+			if (cluster_accumulators[i].n_members == 0)
+				continue;
+
+			cluster_centres[i].red = cluster_accumulators[i].red / cluster_accumulators[i].n_members;
+			cluster_centres[i].green = cluster_accumulators[i].green / cluster_accumulators[i].n_members;
+			cluster_centres[i].blue = cluster_accumulators[i].blue / cluster_accumulators[i].n_members;
+		}
+
+		/* Update assignments of colors to clusters. */
+		n_assignments_changed = 0;
+		for (ClusterPixel8 *p = pixels; p < pixels_end; p++) {
+			gsize new_cluster;
+
+			if (p->cluster >= G_N_ELEMENTS (cluster_centres))
+				continue;
+
+			new_cluster = nearest_cluster (&p->color, cluster_centres, G_N_ELEMENTS (cluster_centres));
+			if (new_cluster != p->cluster)
+				n_assignments_changed++;
+			p->cluster = new_cluster;
+		}
+
+		n_iterations++;
+	} while (n_assignments_changed > assignments_termination_limit && n_iterations < 50);
+
+	/* Output the cluster centres: these are the icon’s key colors. */
+	for (gsize i = 0; i < G_N_ELEMENTS (cluster_centres); i++) {
+		GdkRGBA color;
+
+		if (cluster_accumulators[i].n_members == 0)
+			continue;
+
+		color.red = (gdouble) cluster_centres[i].red / 255.0;
+		color.green = (gdouble) cluster_centres[i].green / 255.0;
+		color.blue = (gdouble) cluster_centres[i].blue / 255.0;
+		color.alpha = 1.0;
+		g_array_append_val (colors, color);
+	}
+}
+
+/**
+ * gs_calculate_key_colors:
+ * @pixbuf: an app icon to calculate key colors from
+ *
+ * Calculate the set of key colors present in @pixbuf. These are the colors
+ * which stand out the most, and they are subjective. This function does not
+ * guarantee to return perfect results, but should return workable results for
+ * most icons.
+ *
+ * @pixbuf will be scaled down to 32×32 pixels, so if it can be provided at
+ * that resolution by the caller, this function will return faster.
+ *
+ * Returns: (transfer full) (element-type GdkRGBA): key colors for @pixbuf
+ * Since: 40
+ */
+GArray *
+gs_calculate_key_colors (GdkPixbuf *pixbuf)
+{
+	g_autoptr(GdkPixbuf) pb_small = NULL;
+	g_autoptr(GArray) colors = g_array_new (FALSE, FALSE, sizeof (GdkRGBA));
+
+	/* people almost always use BILINEAR scaling with pixbufs, but we can
+	 * use NEAREST here since we only care about the rough colour data, not
+	 * whether the edges in the image are smooth and visually appealing;
+	 * NEAREST is twice as fast as BILINEAR */
+	pb_small = gdk_pixbuf_scale_simple (pixbuf, 32, 32, GDK_INTERP_NEAREST);
+
+	/* require an alpha channel for storing temporary values; most images
+	 * have one already, about 2% don’t */
+	if (gdk_pixbuf_get_n_channels (pixbuf) != 4) {
+		g_autoptr(GdkPixbuf) temp = g_steal_pointer (&pb_small);
+		pb_small = gdk_pixbuf_add_alpha (temp, FALSE, 0, 0, 0);
+	}
+
+	/* get a list of key colors */
+	k_means (colors, pb_small);
+
+	return g_steal_pointer (&colors);
+}
diff --git a/lib/gs-key-colors.h b/lib/gs-key-colors.h
new file mode 100644
index 0000000..de1baee
--- /dev/null
+++ b/lib/gs-key-colors.h
@@ -0,0 +1,27 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2013-2016 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2013 Matthias Clasen <mclasen@redhat.com>
+ * Copyright (C) 2014-2018 Kalev Lember <klember@redhat.com>
+ * Copyright (C) 2021 Endless OS Foundation LLC
+ *
+ * Authors:
+ *  - Richard Hughes <richard@hughsie.com>
+ *  - Kalev Lember <klember@redhat.com>
+ *  - Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <gdk/gdk.h>
+#include <gdk-pixbuf/gdk-pixbuf.h>
+
+G_BEGIN_DECLS
+
+GArray	*gs_calculate_key_colors	(GdkPixbuf	*pixbuf);
+
+G_END_DECLS
diff --git a/lib/gs-metered.c b/lib/gs-metered.c
new file mode 100644
index 0000000..e6a82d9
--- /dev/null
+++ b/lib/gs-metered.c
@@ -0,0 +1,312 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2019 Endless Mobile, Inc.
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-metered
+ * @title: Metered Data Utilities
+ * @include: gnome-software.h
+ * @stability: Unstable
+ * @short_description: Utility functions to help with metered data handling
+ *
+ * Metered data handling is provided by Mogwai, which implements a download
+ * scheduler to control when, and in which order, large downloads happen on
+ * the system.
+ *
+ * All large downloads from gs_plugin_download() or gs_plugin_download_app()
+ * calls should be scheduled using Mogwai, which will notify gnome-software
+ * when those downloads can start and stop, according to system policy.
+ *
+ * The functions in this file make interacting with the scheduling daemon a
+ * little simpler. Since all #GsPlugin method calls happen in worker threads,
+ * typically without a #GMainContext, all interaction with the scheduler should
+ * be blocking. libmogwai-schedule-client was designed to be asynchronous; so
+ * these helpers make it synchronous.
+ *
+ * Since: 3.34
+ */
+
+#include "config.h"
+
+#include <glib.h>
+
+#ifdef HAVE_MOGWAI
+#include <libmogwai-schedule-client/scheduler.h>
+#endif
+
+#include "gs-metered.h"
+#include "gs-utils.h"
+
+
+#ifdef HAVE_MOGWAI
+
+typedef struct
+{
+	gboolean *out_download_now;  /* (unowned) */
+	GMainContext *context;  /* (unowned) */
+} DownloadNowData;
+
+static void
+download_now_cb (GObject    *obj,
+                 GParamSpec *pspec,
+                 gpointer    user_data)
+{
+	DownloadNowData *data = user_data;
+	*data->out_download_now = mwsc_schedule_entry_get_download_now (MWSC_SCHEDULE_ENTRY (obj));
+	g_main_context_wakeup (data->context);
+}
+
+typedef struct
+{
+	GError **out_error;  /* (unowned) */
+	GMainContext *context;  /* (unowned) */
+} InvalidatedData;
+
+static void
+invalidated_cb (MwscScheduleEntry *entry,
+                const GError      *error,
+                gpointer           user_data)
+{
+	InvalidatedData *data = user_data;
+	*data->out_error = g_error_copy (error);
+	g_main_context_wakeup (data->context);
+}
+
+#endif  /* HAVE_MOGWAI */
+
+/**
+ * gs_metered_block_on_download_scheduler:
+ * @parameters: (nullable): a #GVariant of type `a{sv}` specifying parameters
+ *    for the schedule entry, or %NULL to pass no parameters
+ * @schedule_entry_handle_out: (out) (not optional): return location for a
+ *    handle to the resulting schedule entry
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @error: return location for a #GError, or %NULL
+ *
+ * Create a schedule entry with the given @parameters, and block until
+ * permission is given to download.
+ *
+ * FIXME: This will currently ignore later revocations of that download
+ * permission, and does not support creating a schedule entry per app.
+ * The schedule entry must later be removed from the schedule by passing
+ * the handle from @schedule_entry_handle_out to
+ * gs_metered_remove_from_download_scheduler(), otherwise resources will leak.
+ * This is an opaque handle and should not be inspected.
+ *
+ * If a schedule entry cannot be created, or if @cancellable is cancelled,
+ * an error will be set and %FALSE returned.
+ *
+ * The keys understood by @parameters are listed in the documentation for
+ * mwsc_scheduler_schedule_async().
+ *
+ * This function will likely be called from a #GsPluginLoader worker thread.
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 3.38
+ */
+gboolean
+gs_metered_block_on_download_scheduler (GVariant      *parameters,
+                                        gpointer      *schedule_entry_handle_out,
+                                        GCancellable  *cancellable,
+                                        GError       **error)
+{
+#ifdef HAVE_MOGWAI
+	g_autoptr(MwscScheduler) scheduler = NULL;
+	g_autoptr(MwscScheduleEntry) schedule_entry = NULL;
+	g_autofree gchar *parameters_str = NULL;
+	g_autoptr(GMainContext) context = NULL;
+	g_autoptr(GMainContextPusher) pusher = NULL;
+
+	g_return_val_if_fail (schedule_entry_handle_out != NULL, FALSE);
+
+	/* set this in case of error */
+	*schedule_entry_handle_out = NULL;
+
+	parameters_str = (parameters != NULL) ? g_variant_print (parameters, TRUE) : g_strdup ("(none)");
+	g_debug ("%s: Waiting with parameters: %s", G_STRFUNC, parameters_str);
+
+	/* Push the context early so that the #MwscScheduler is created to run within it. */
+	context = g_main_context_new ();
+	pusher = g_main_context_pusher_new (context);
+
+	/* Wait until the download can be scheduled.
+	 * FIXME: In future, downloads could be split up by app, so they can all
+	 * be scheduled separately and, for example, higher priority ones could
+	 * be scheduled with a higher priority. This would have to be aware of
+	 * dependencies. */
+	scheduler = mwsc_scheduler_new (cancellable, error);
+	if (scheduler == NULL)
+		return FALSE;
+
+	/* Create a schedule entry for the group of downloads.
+	 * FIXME: The underlying OSTree code supports resuming downloads
+	 * (at a granularity of individual objects), so it should be
+	 * possible to plumb through here. */
+	schedule_entry = mwsc_scheduler_schedule (scheduler, parameters, cancellable,
+						  error);
+	if (schedule_entry == NULL)
+		return FALSE;
+
+	/* Wait until the download is allowed to proceed. */
+	if (!mwsc_schedule_entry_get_download_now (schedule_entry)) {
+		gboolean download_now = FALSE;
+		g_autoptr(GError) invalidated_error = NULL;
+		gulong notify_id, invalidated_id;
+		DownloadNowData download_now_data = { &download_now, context };
+		InvalidatedData invalidated_data = { &invalidated_error, context };
+
+		notify_id = g_signal_connect (schedule_entry, "notify::download-now",
+					      (GCallback) download_now_cb, &download_now_data);
+		invalidated_id = g_signal_connect (schedule_entry, "invalidated",
+						   (GCallback) invalidated_cb, &invalidated_data);
+
+		while (!download_now && invalidated_error == NULL &&
+		       !g_cancellable_is_cancelled (cancellable))
+			g_main_context_iteration (context, TRUE);
+
+		g_signal_handler_disconnect (schedule_entry, invalidated_id);
+		g_signal_handler_disconnect (schedule_entry, notify_id);
+
+		if (!download_now && invalidated_error != NULL) {
+			/* no need to remove the schedule entry as it’s been
+			 * invalidated */
+			g_propagate_error (error, g_steal_pointer (&invalidated_error));
+			return FALSE;
+		} else if (!download_now && g_cancellable_set_error_if_cancelled (cancellable, error)) {
+			/* remove the schedule entry and fail */
+			gs_metered_remove_from_download_scheduler (schedule_entry, NULL, NULL);
+			return FALSE;
+		}
+
+		g_assert (download_now);
+	}
+
+	*schedule_entry_handle_out = g_object_ref (schedule_entry);
+
+	g_debug ("%s: Allowed to download", G_STRFUNC);
+#else  /* if !HAVE_MOGWAI */
+	g_debug ("%s: Allowed to download (Mogwai support compiled out)", G_STRFUNC);
+#endif  /* !HAVE_MOGWAI */
+
+	return TRUE;
+}
+
+/**
+ * gs_metered_remove_from_download_scheduler:
+ * @schedule_entry_handle: (transfer full) (nullable): schedule entry handle as
+ *    returned by gs_metered_block_on_download_scheduler()
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @error: return location for a #GError, or %NULL
+ *
+ * Remove a schedule entry previously created by
+ * gs_metered_block_on_download_scheduler(). This must be called after
+ * gs_metered_block_on_download_scheduler() has successfully returned, or
+ * resources will leak. It should be called once the corresponding download is
+ * complete.
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 3.38
+ */
+gboolean
+gs_metered_remove_from_download_scheduler (gpointer       schedule_entry_handle,
+                                           GCancellable  *cancellable,
+                                           GError       **error)
+{
+#ifdef HAVE_MOGWAI
+	g_autoptr(MwscScheduleEntry) schedule_entry = schedule_entry_handle;
+#endif
+
+	g_return_val_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable), FALSE);
+	g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
+
+	g_debug ("Removing schedule entry handle %p", schedule_entry_handle);
+
+	if (schedule_entry_handle == NULL)
+		return TRUE;
+
+#ifdef HAVE_MOGWAI
+	return mwsc_schedule_entry_remove (schedule_entry, cancellable, error);
+#else
+	return TRUE;
+#endif
+}
+
+/**
+ * gs_metered_block_app_on_download_scheduler:
+ * @app: a #GsApp to get the scheduler parameters from
+ * @schedule_entry_handle_out: (out) (not optional): return location for a
+ *    handle to the resulting schedule entry
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: return location for a #GError, or %NULL
+ *
+ * Version of gs_metered_block_on_download_scheduler() which extracts the
+ * download parameters from the given @app.
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 3.38
+ */
+gboolean
+gs_metered_block_app_on_download_scheduler (GsApp         *app,
+                                            gpointer      *schedule_entry_handle_out,
+                                            GCancellable  *cancellable,
+                                            GError       **error)
+{
+	g_auto(GVariantDict) parameters_dict = G_VARIANT_DICT_INIT (NULL);
+	g_autoptr(GVariant) parameters = NULL;
+	guint64 download_size;
+
+	/* Currently no plugins support resumable downloads. This may change in
+	 * future, in which case this parameter should be refactored. */
+	g_variant_dict_insert (&parameters_dict, "resumable", "b", FALSE);
+
+	if (gs_app_get_size_download (app, &download_size) == GS_SIZE_TYPE_VALID) {
+		g_variant_dict_insert (&parameters_dict, "size-minimum", "t", download_size);
+		g_variant_dict_insert (&parameters_dict, "size-maximum", "t", download_size);
+	}
+
+	parameters = g_variant_ref_sink (g_variant_dict_end (&parameters_dict));
+
+	return gs_metered_block_on_download_scheduler (parameters, schedule_entry_handle_out, cancellable, error);
+}
+
+/**
+ * gs_metered_block_app_list_on_download_scheduler:
+ * @app_list: a #GsAppList to get the scheduler parameters from
+ * @schedule_entry_handle_out: (out) (not optional): return location for a
+ *    handle to the resulting schedule entry
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: return location for a #GError, or %NULL
+ *
+ * Version of gs_metered_block_on_download_scheduler() which extracts the
+ * download parameters from the apps in the given @app_list.
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 3.38
+ */
+gboolean
+gs_metered_block_app_list_on_download_scheduler (GsAppList     *app_list,
+                                                 gpointer      *schedule_entry_handle_out,
+                                                 GCancellable  *cancellable,
+                                                 GError       **error)
+{
+	g_auto(GVariantDict) parameters_dict = G_VARIANT_DICT_INIT (NULL);
+	g_autoptr(GVariant) parameters = NULL;
+
+	/* Currently no plugins support resumable downloads. This may change in
+	 * future, in which case this parameter should be refactored. */
+	g_variant_dict_insert (&parameters_dict, "resumable", "b", FALSE);
+
+	/* FIXME: Currently this creates a single Mogwai schedule entry for the
+	 * entire app list. Eventually, we probably want one schedule entry per
+	 * app being downloaded, so that they can be individually prioritised.
+	 * However, that requires much deeper integration into the download
+	 * code, and Mogwai does not currently support that level of
+	 * prioritisation, so go with this simple implementation for now. */
+	parameters = g_variant_ref_sink (g_variant_dict_end (&parameters_dict));
+
+	return gs_metered_block_on_download_scheduler (parameters, schedule_entry_handle_out, cancellable, error);
+}
diff --git a/lib/gs-metered.h b/lib/gs-metered.h
new file mode 100644
index 0000000..f81d171
--- /dev/null
+++ b/lib/gs-metered.h
@@ -0,0 +1,35 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2019 Endless Mobile, Inc.
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib-object.h>
+#include <gio/gio.h>
+
+#include "gs-app.h"
+#include "gs-app-list.h"
+
+G_BEGIN_DECLS
+
+gboolean gs_metered_block_on_download_scheduler (GVariant      *parameters,
+                                                 gpointer      *schedule_entry_handle_out,
+                                                 GCancellable  *cancellable,
+                                                 GError       **error);
+gboolean gs_metered_remove_from_download_scheduler (gpointer       schedule_entry_handle,
+                                                    GCancellable  *cancellable,
+                                                    GError       **error);
+gboolean gs_metered_block_app_on_download_scheduler (GsApp         *app,
+                                                     gpointer      *schedule_entry_handle_out,
+                                                     GCancellable  *cancellable,
+                                                     GError       **error);
+gboolean gs_metered_block_app_list_on_download_scheduler (GsAppList     *app_list,
+                                                          gpointer      *schedule_entry_handle_out,
+                                                          GCancellable  *cancellable,
+                                                          GError       **error);
+
+G_END_DECLS
diff --git a/lib/gs-odrs-provider.c b/lib/gs-odrs-provider.c
new file mode 100644
index 0000000..cb9d37d
--- /dev/null
+++ b/lib/gs-odrs-provider.c
@@ -0,0 +1,1998 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2016 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2016-2018 Kalev Lember <klember@redhat.com>
+ * Copyright (C) 2021 Endless OS Foundation LLC
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/*
+ * SECTION:gs-odrs-provider
+ * @short_description: Provides review data from the Open Desktop Ratings Service.
+ *
+ * To test this plugin locally you will probably want to build and run the
+ * `odrs-web` container, following the instructions in the
+ * [`odrs-web` repository](https://gitlab.gnome.org/Infrastructure/odrs-web/-/blob/HEAD/app_data/README.md),
+ * and then get gnome-software to use your local review server by running:
+ * ```
+ * gsettings set org.gnome.software review-server 'http://127.0.0.1:5000/1.0/reviews/api'
+ * ```
+ *
+ * When you are done with development, run the following command to use the real
+ * ODRS server again:
+ * ```
+ * gsettings reset org.gnome.software review-server
+ * ```
+ *
+ * Since: 41
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <glib-object.h>
+#include <glib/gi18n.h>
+#include <gnome-software.h>
+#include <json-glib/json-glib.h>
+#include <libsoup/soup.h>
+#include <locale.h>
+#include <math.h>
+#include <string.h>
+
+G_DEFINE_QUARK (gs-odrs-provider-error-quark, gs_odrs_provider_error)
+
+/* Element in self->ratings, all allocated in one big block and sorted
+ * alphabetically to reduce the number of allocations and fragmentation. */
+typedef struct {
+	gchar *app_id;  /* (owned) */
+	guint32 n_star_ratings[6];
+} GsOdrsRating;
+
+static int
+rating_compare (const GsOdrsRating *a, const GsOdrsRating *b)
+{
+	return g_strcmp0 (a->app_id, b->app_id);
+}
+
+static void
+rating_clear (GsOdrsRating *rating)
+{
+	g_free (rating->app_id);
+}
+
+struct _GsOdrsProvider
+{
+	GObject		 parent_instance;
+
+	gchar		*distro;  /* (not nullable) (owned) */
+	gchar		*user_hash;  /* (not nullable) (owned) */
+	gchar		*review_server;  /* (not nullable) (owned) */
+	GArray		*ratings;  /* (element-type GsOdrsRating) (mutex ratings_mutex) (owned) (nullable) */
+	GMutex		 ratings_mutex;
+	guint64		 max_cache_age_secs;
+	guint		 n_results_max;
+	SoupSession	*session;  /* (owned) (not nullable) */
+};
+
+G_DEFINE_TYPE (GsOdrsProvider, gs_odrs_provider, G_TYPE_OBJECT)
+
+typedef enum {
+	PROP_REVIEW_SERVER = 1,
+	PROP_USER_HASH,
+	PROP_DISTRO,
+	PROP_MAX_CACHE_AGE_SECS,
+	PROP_N_RESULTS_MAX,
+	PROP_SESSION,
+} GsOdrsProviderProperty;
+
+static GParamSpec *obj_props[PROP_SESSION + 1] = { NULL, };
+
+static gboolean
+gs_odrs_provider_load_ratings_for_app (JsonObject   *json_app,
+                                       const gchar  *app_id,
+                                       GsOdrsRating *rating_out)
+{
+	guint i;
+	const gchar *names[] = { "star0", "star1", "star2", "star3",
+				 "star4", "star5", NULL };
+
+	for (i = 0; names[i] != NULL; i++) {
+		if (!json_object_has_member (json_app, names[i]))
+			return FALSE;
+		rating_out->n_star_ratings[i] = (guint64) json_object_get_int_member (json_app, names[i]);
+	}
+
+	rating_out->app_id = g_strdup (app_id);
+
+	return TRUE;
+}
+
+static gboolean
+gs_odrs_provider_load_ratings (GsOdrsProvider  *self,
+                               const gchar     *filename,
+                               GError         **error)
+{
+	JsonNode *json_root;
+	JsonObject *json_item;
+	g_autoptr(JsonParser) json_parser = NULL;
+	const gchar *app_id;
+	JsonNode *json_app_node;
+	JsonObjectIter iter;
+	g_autoptr(GArray) new_ratings = NULL;
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	/* parse the data and find the success */
+	json_parser = json_parser_new_immutable ();
+	if (!json_parser_load_from_mapped_file (json_parser, filename, &local_error)) {
+		g_set_error (error,
+			     GS_ODRS_PROVIDER_ERROR,
+			     GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+			     "Error parsing ODRS data: %s", local_error->message);
+		return FALSE;
+	}
+	json_root = json_parser_get_root (json_parser);
+	if (json_root == NULL) {
+		g_set_error_literal (error,
+				     GS_ODRS_PROVIDER_ERROR,
+				     GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+				     "no ratings root");
+		return FALSE;
+	}
+	if (json_node_get_node_type (json_root) != JSON_NODE_OBJECT) {
+		g_set_error_literal (error,
+				     GS_ODRS_PROVIDER_ERROR,
+				     GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+				     "no ratings array");
+		return FALSE;
+	}
+
+	json_item = json_node_get_object (json_root);
+
+	new_ratings = g_array_sized_new (FALSE,  /* don’t zero-terminate */
+					 FALSE,  /* don’t clear */
+					 sizeof (GsOdrsRating),
+					 json_object_get_size (json_item));
+	g_array_set_clear_func (new_ratings, (GDestroyNotify) rating_clear);
+
+	/* parse each app */
+	json_object_iter_init (&iter, json_item);
+	while (json_object_iter_next (&iter, &app_id, &json_app_node)) {
+		GsOdrsRating rating;
+		JsonObject *json_app;
+
+		if (!JSON_NODE_HOLDS_OBJECT (json_app_node))
+			continue;
+		json_app = json_node_get_object (json_app_node);
+
+		if (gs_odrs_provider_load_ratings_for_app (json_app, app_id, &rating))
+			g_array_append_val (new_ratings, rating);
+	}
+
+	/* Allow for binary searches later. */
+	g_array_sort (new_ratings, (GCompareFunc) rating_compare);
+
+	/* Update the shared state */
+	locker = g_mutex_locker_new (&self->ratings_mutex);
+	g_clear_pointer (&self->ratings, g_array_unref);
+	self->ratings = g_steal_pointer (&new_ratings);
+
+	return TRUE;
+}
+
+static AsReview *
+gs_odrs_provider_parse_review_object (JsonObject *item)
+{
+	AsReview *rev = as_review_new ();
+
+	/* date */
+	if (json_object_has_member (item, "date_created")) {
+		gint64 timestamp;
+		g_autoptr(GDateTime) dt = NULL;
+		timestamp = json_object_get_int_member (item, "date_created");
+		dt = g_date_time_new_from_unix_utc (timestamp);
+		as_review_set_date (rev, dt);
+	}
+
+	/* assemble review */
+	if (json_object_has_member (item, "rating"))
+		as_review_set_rating (rev, (gint) json_object_get_int_member (item, "rating"));
+	if (json_object_has_member (item, "score")) {
+		as_review_set_priority (rev, (gint) json_object_get_int_member (item, "score"));
+	} else if (json_object_has_member (item, "karma_up") &&
+		   json_object_has_member (item, "karma_down")) {
+		gdouble ku = (gdouble) json_object_get_int_member (item, "karma_up");
+		gdouble kd = (gdouble) json_object_get_int_member (item, "karma_down");
+		gdouble wilson = 0.f;
+
+		/* from http://www.evanmiller.org/how-not-to-sort-by-average-rating.html */
+		if (ku > 0 || kd > 0) {
+			wilson = ((ku + 1.9208) / (ku + kd) -
+				  1.96 * sqrt ((ku * kd) / (ku + kd) + 0.9604) /
+				  (ku + kd)) / (1 + 3.8416 / (ku + kd));
+			wilson *= 100.f;
+		}
+		as_review_set_priority (rev, (gint) wilson);
+	}
+	if (json_object_has_member (item, "user_hash"))
+		as_review_set_reviewer_id (rev, json_object_get_string_member (item, "user_hash"));
+	if (json_object_has_member (item, "user_display")) {
+		g_autofree gchar *user_display = g_strdup (json_object_get_string_member (item, "user_display"));
+		if (user_display)
+			g_strstrip (user_display);
+		as_review_set_reviewer_name (rev, user_display);
+	}
+	if (json_object_has_member (item, "summary")) {
+		g_autofree gchar *summary = g_strdup (json_object_get_string_member (item, "summary"));
+		if (summary)
+			g_strstrip (summary);
+		as_review_set_summary (rev, summary);
+	}
+	if (json_object_has_member (item, "description")) {
+		g_autofree gchar *description = g_strdup (json_object_get_string_member (item, "description"));
+		if (description)
+			g_strstrip (description);
+		as_review_set_description (rev, description);
+	}
+	if (json_object_has_member (item, "version"))
+		as_review_set_version (rev, json_object_get_string_member (item, "version"));
+
+	/* add extra metadata for the plugin */
+	if (json_object_has_member (item, "user_skey")) {
+		as_review_add_metadata (rev, "user_skey",
+					json_object_get_string_member (item, "user_skey"));
+	}
+	if (json_object_has_member (item, "app_id")) {
+		as_review_add_metadata (rev, "app_id",
+					json_object_get_string_member (item, "app_id"));
+	}
+	if (json_object_has_member (item, "review_id")) {
+		g_autofree gchar *review_id = NULL;
+		review_id = g_strdup_printf ("%" G_GINT64_FORMAT,
+					json_object_get_int_member (item, "review_id"));
+		as_review_set_id (rev, review_id);
+	}
+
+	/* don't allow multiple votes */
+	if (json_object_has_member (item, "vote_id"))
+		as_review_add_flags (rev, AS_REVIEW_FLAG_VOTED);
+
+	return rev;
+}
+
+/* json_parser_load*() must have been called on @json_parser before calling
+ * this function. */
+static GPtrArray *
+gs_odrs_provider_parse_reviews (GsOdrsProvider  *self,
+                                JsonParser      *json_parser,
+                                GError         **error)
+{
+	JsonArray *json_reviews;
+	JsonNode *json_root;
+	guint i;
+	g_autoptr(GHashTable) reviewer_ids = NULL;
+	g_autoptr(GPtrArray) reviews = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	json_root = json_parser_get_root (json_parser);
+	if (json_root == NULL) {
+		g_set_error_literal (error,
+				     GS_ODRS_PROVIDER_ERROR,
+				     GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+				     "no root");
+		return NULL;
+	}
+	if (json_node_get_node_type (json_root) != JSON_NODE_ARRAY) {
+		g_set_error_literal (error,
+				     GS_ODRS_PROVIDER_ERROR,
+				     GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+				     "no array");
+		return NULL;
+	}
+
+	/* parse each rating */
+	reviews = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);
+	json_reviews = json_node_get_array (json_root);
+	reviewer_ids = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
+	for (i = 0; i < json_array_get_length (json_reviews); i++) {
+		JsonNode *json_review;
+		JsonObject *json_item;
+		const gchar *reviewer_id;
+		g_autoptr(AsReview) review = NULL;
+
+		/* extract the data */
+		json_review = json_array_get_element (json_reviews, i);
+		if (json_node_get_node_type (json_review) != JSON_NODE_OBJECT) {
+			g_set_error_literal (error,
+					     GS_ODRS_PROVIDER_ERROR,
+					     GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+					     "no object type");
+			return NULL;
+		}
+		json_item = json_node_get_object (json_review);
+		if (json_item == NULL) {
+			g_set_error_literal (error,
+					     GS_ODRS_PROVIDER_ERROR,
+					     GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+					     "no object");
+			return NULL;
+		}
+
+		/* create review */
+		review = gs_odrs_provider_parse_review_object (json_item);
+
+		reviewer_id = as_review_get_reviewer_id (review);
+		if (reviewer_id == NULL)
+			continue;
+
+		/* dedupe each on the user_hash */
+		if (g_hash_table_lookup (reviewer_ids, reviewer_id) != NULL) {
+			g_debug ("duplicate review %s, skipping", reviewer_id);
+			continue;
+		}
+		g_hash_table_add (reviewer_ids, g_strdup (reviewer_id));
+		g_ptr_array_add (reviews, g_object_ref (review));
+	}
+	return g_steal_pointer (&reviews);
+}
+
+static gboolean
+gs_odrs_provider_parse_success (GInputStream  *input_stream,
+                                GError       **error)
+{
+	JsonNode *json_root;
+	JsonObject *json_item;
+	const gchar *msg = NULL;
+	g_autoptr(JsonParser) json_parser = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	/* parse the data and find the success
+	 * FIXME: This should probably eventually be refactored and made async */
+	json_parser = json_parser_new_immutable ();
+	if (!json_parser_load_from_stream (json_parser, input_stream, NULL, &local_error)) {
+		g_set_error (error,
+			     GS_ODRS_PROVIDER_ERROR,
+			     GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+			     "Error parsing ODRS data: %s", local_error->message);
+		return FALSE;
+	}
+	json_root = json_parser_get_root (json_parser);
+	if (json_root == NULL) {
+		g_set_error_literal (error,
+				     GS_ODRS_PROVIDER_ERROR,
+				     GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+				     "no error root");
+		return FALSE;
+	}
+	if (json_node_get_node_type (json_root) != JSON_NODE_OBJECT) {
+		g_set_error_literal (error,
+				     GS_ODRS_PROVIDER_ERROR,
+				     GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+				     "no error object");
+		return FALSE;
+	}
+	json_item = json_node_get_object (json_root);
+	if (json_item == NULL) {
+		g_set_error_literal (error,
+				     GS_ODRS_PROVIDER_ERROR,
+				     GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+				     "no error object");
+		return FALSE;
+	}
+
+	/* failed? */
+	if (json_object_has_member (json_item, "msg"))
+		msg = json_object_get_string_member (json_item, "msg");
+	if (!json_object_get_boolean_member (json_item, "success")) {
+		g_set_error_literal (error,
+				     GS_ODRS_PROVIDER_ERROR,
+				     GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+				     msg != NULL ? msg : "unknown failure");
+		return FALSE;
+	}
+
+	/* just for the console */
+	if (msg != NULL)
+		g_debug ("success: %s", msg);
+	return TRUE;
+}
+
+#if SOUP_CHECK_VERSION(3, 0, 0)
+typedef struct {
+	GInputStream *input_stream;
+	gssize length;
+	goffset read_from;
+} MessageData;
+
+static MessageData *
+message_data_new (GInputStream *input_stream,
+		  gssize length)
+{
+	MessageData *md;
+
+	md = g_slice_new0 (MessageData);
+	md->input_stream = g_object_ref (input_stream);
+	md->length = length;
+
+	if (G_IS_SEEKABLE (input_stream))
+		md->read_from = g_seekable_tell (G_SEEKABLE (input_stream));
+
+	return md;
+}
+
+static void
+message_data_free (gpointer ptr,
+		   GClosure *closure)
+{
+	MessageData *md = ptr;
+
+	if (md) {
+		g_object_unref (md->input_stream);
+		g_slice_free (MessageData, md);
+	}
+}
+
+static void
+g_odrs_provider_message_restarted_cb (SoupMessage *message,
+				      gpointer user_data)
+{
+	MessageData *md = user_data;
+
+	if (G_IS_SEEKABLE (md->input_stream) && md->read_from != g_seekable_tell (G_SEEKABLE (md->input_stream)))
+		g_seekable_seek (G_SEEKABLE (md->input_stream), md->read_from, G_SEEK_SET, NULL, NULL);
+
+	soup_message_set_request_body (message, NULL, md->input_stream, md->length);
+}
+
+static void
+g_odrs_provider_set_message_request_body (SoupMessage *message,
+					  const gchar *content_type,
+					  gconstpointer data,
+					  gsize length)
+{
+	MessageData *md;
+	GInputStream *input_stream;
+
+	g_return_if_fail (SOUP_IS_MESSAGE (message));
+	g_return_if_fail (data != NULL);
+
+	input_stream = g_memory_input_stream_new_from_data (g_memdup2 (data, length), length, g_free);
+	md = message_data_new (input_stream, length);
+
+	g_signal_connect_data (message, "restarted",
+		G_CALLBACK (g_odrs_provider_message_restarted_cb), md, message_data_free, 0);
+
+	soup_message_set_request_body (message, content_type, input_stream, length);
+
+	g_object_unref (input_stream);
+}
+#endif
+
+static gboolean
+gs_odrs_provider_json_post (SoupSession  *session,
+                            const gchar  *uri,
+                            const gchar  *data,
+			    GCancellable *cancellable,
+                            GError      **error)
+{
+	guint status_code;
+	g_autoptr(SoupMessage) msg = NULL;
+	gconstpointer downloaded_data;
+	gsize downloaded_data_length;
+	g_autoptr(GInputStream) input_stream = NULL;
+#if SOUP_CHECK_VERSION(3, 0, 0)
+	g_autoptr(GBytes) bytes = NULL;
+#endif
+	/* create the GET data */
+	g_debug ("Sending ODRS request to %s: %s", uri, data);
+	msg = soup_message_new (SOUP_METHOD_POST, uri);
+#if SOUP_CHECK_VERSION(3, 0, 0)
+	g_odrs_provider_set_message_request_body (msg, "application/json; charset=utf-8",
+						  data, strlen (data));
+	bytes = soup_session_send_and_read (session, msg, cancellable, error);
+	if (bytes == NULL)
+		return FALSE;
+
+	downloaded_data = g_bytes_get_data (bytes, &downloaded_data_length);
+	status_code = soup_message_get_status (msg);
+#else
+	soup_message_set_request (msg, "application/json; charset=utf-8",
+				  SOUP_MEMORY_COPY, data, strlen (data));
+
+	/* set sync request */
+	status_code = soup_session_send_message (session, msg);
+	downloaded_data = msg->response_body ? msg->response_body->data : NULL;
+	downloaded_data_length = msg->response_body ? msg->response_body->length : 0;
+#endif
+	g_debug ("ODRS server returned status %u: %.*s", status_code, (gint) downloaded_data_length, (const gchar *) downloaded_data);
+	if (status_code != SOUP_STATUS_OK) {
+		g_warning ("Failed to set rating on ODRS: %s",
+			   soup_status_get_phrase (status_code));
+		g_set_error (error,
+                             GS_ODRS_PROVIDER_ERROR,
+                             GS_ODRS_PROVIDER_ERROR_SERVER_ERROR,
+                             "Failed to submit review to ODRS: %s", soup_status_get_phrase (status_code));
+		return FALSE;
+	}
+
+	/* process returned JSON */
+	input_stream = g_memory_input_stream_new_from_data (downloaded_data, downloaded_data_length, NULL);
+	return gs_odrs_provider_parse_success (input_stream, error);
+}
+
+static GPtrArray *
+_gs_app_get_reviewable_ids (GsApp *app)
+{
+	GPtrArray *ids = g_ptr_array_new_with_free_func (g_free);
+	GPtrArray *provided = gs_app_get_provided (app);
+
+	/* add the main component id */
+	g_ptr_array_add (ids, g_strdup (gs_app_get_id (app)));
+
+	/* add any ID provides */
+	for (guint i = 0; i < provided->len; i++) {
+		GPtrArray *items;
+		AsProvided *prov = g_ptr_array_index (provided, i);
+		if (as_provided_get_kind (prov) != AS_PROVIDED_KIND_ID)
+			continue;
+
+		items = as_provided_get_items (prov);
+		for (guint j = 0; j < items->len; j++) {
+			const gchar *value = (const gchar *) g_ptr_array_index (items, j);
+			if (value == NULL)
+				continue;
+			g_ptr_array_add (ids, g_strdup (value));
+		}
+	}
+	return ids;
+}
+
+static gboolean
+gs_odrs_provider_refine_ratings (GsOdrsProvider  *self,
+                                 GsApp           *app,
+                                 GCancellable    *cancellable,
+                                 GError         **error)
+{
+	gint rating;
+	guint32 ratings_raw[6] = { 0, 0, 0, 0, 0, 0 };
+	guint cnt = 0;
+	g_autoptr(GArray) review_ratings = NULL;
+	g_autoptr(GPtrArray) reviewable_ids = NULL;
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	/* get ratings for each reviewable ID */
+	reviewable_ids = _gs_app_get_reviewable_ids (app);
+
+	locker = g_mutex_locker_new (&self->ratings_mutex);
+
+	if (!self->ratings) {
+		g_autofree gchar *cache_filename = NULL;
+
+		g_clear_pointer (&locker, g_mutex_locker_free);
+
+		/* Load from the local cache, if available, when in offline or
+		   when refresh/download disabled on start */
+		cache_filename = gs_utils_get_cache_filename ("odrs",
+							      "ratings.json",
+							      GS_UTILS_CACHE_FLAG_WRITEABLE |
+							      GS_UTILS_CACHE_FLAG_CREATE_DIRECTORY,
+							      error);
+
+		if (!cache_filename)
+			return TRUE;
+
+		if (!gs_odrs_provider_load_ratings (self, cache_filename, NULL)) {
+			g_autoptr(GFile) cache_file = g_file_new_for_path (cache_filename);
+			g_debug ("Failed to load cache file ‘%s’, deleting it", cache_filename);
+			g_file_delete (cache_file, NULL, NULL);
+			return TRUE;
+		}
+
+		locker = g_mutex_locker_new (&self->ratings_mutex);
+
+		if (!self->ratings)
+			return TRUE;
+	}
+
+	for (guint i = 0; i < reviewable_ids->len; i++) {
+		const gchar *id = g_ptr_array_index (reviewable_ids, i);
+		const GsOdrsRating search_rating = { (gchar *) id, { 0, }};
+		guint found_index;
+		const GsOdrsRating *found_rating;
+
+		if (!g_array_binary_search (self->ratings, &search_rating,
+					    (GCompareFunc) rating_compare, &found_index))
+			continue;
+
+		found_rating = &g_array_index (self->ratings, GsOdrsRating, found_index);
+
+		/* copy into accumulator array */
+		for (guint j = 0; j < 6; j++)
+			ratings_raw[j] += found_rating->n_star_ratings[j];
+		cnt++;
+	}
+	if (cnt == 0)
+		return TRUE;
+
+	/* Done with self->ratings now */
+	g_clear_pointer (&locker, g_mutex_locker_free);
+
+	/* merge to accumulator array back to one GArray blob */
+	review_ratings = g_array_sized_new (FALSE, TRUE, sizeof(guint32), 6);
+	for (guint i = 0; i < 6; i++)
+		g_array_append_val (review_ratings, ratings_raw[i]);
+	gs_app_set_review_ratings (app, review_ratings);
+
+	/* find the wilson rating */
+	rating = gs_utils_get_wilson_rating (g_array_index (review_ratings, guint32, 1),
+					     g_array_index (review_ratings, guint32, 2),
+					     g_array_index (review_ratings, guint32, 3),
+					     g_array_index (review_ratings, guint32, 4),
+					     g_array_index (review_ratings, guint32, 5));
+	if (rating > 0)
+		gs_app_set_rating (app, rating);
+	return TRUE;
+}
+
+static JsonNode *
+gs_odrs_provider_get_compat_ids (GsApp *app)
+{
+	GPtrArray *provided = gs_app_get_provided (app);
+	g_autoptr(GHashTable) ids = NULL;
+	g_autoptr(JsonArray) json_array = json_array_new ();
+	g_autoptr(JsonNode) json_node = json_node_new (JSON_NODE_ARRAY);
+
+	ids = g_hash_table_new_full (g_str_hash, g_str_equal, NULL, NULL);
+	for (guint i = 0; i < provided->len; i++) {
+		GPtrArray *items;
+		AsProvided *prov = g_ptr_array_index (provided, i);
+
+		if (as_provided_get_kind (prov) != AS_PROVIDED_KIND_ID)
+			continue;
+
+		items = as_provided_get_items (prov);
+		for (guint j = 0; j < items->len; j++) {
+			const gchar *value = g_ptr_array_index (items, j);
+			if (value == NULL)
+				continue;
+
+			if (g_hash_table_add (ids, (gpointer) value))
+				json_array_add_string_element (json_array, value);
+		}
+	}
+	if (json_array_get_length (json_array) == 0)
+		return NULL;
+	json_node_set_array (json_node, json_array);
+	return g_steal_pointer (&json_node);
+}
+
+static void open_input_stream_cb (GObject      *source_object,
+                                  GAsyncResult *result,
+                                  gpointer      user_data);
+static void parse_reviews_cb (GObject      *source_object,
+                              GAsyncResult *result,
+                              gpointer      user_data);
+static void set_reviews_on_app (GsOdrsProvider *self,
+                                GsApp          *app,
+                                GPtrArray      *reviews);
+
+typedef struct {
+	GsApp *app;  /* (not nullable) (owned) */
+	gchar *cache_filename;  /* (not nullable) (owned) */
+	SoupMessage *message;  /* (nullable) (owned) */
+} FetchReviewsForAppData;
+
+static void
+fetch_reviews_for_app_data_free (FetchReviewsForAppData *data)
+{
+	g_clear_object (&data->app);
+	g_free (data->cache_filename);
+	g_clear_object (&data->message);
+
+	g_free (data);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (FetchReviewsForAppData, fetch_reviews_for_app_data_free)
+
+static void
+gs_odrs_provider_fetch_reviews_for_app_async (GsOdrsProvider      *self,
+                                              GsApp               *app,
+                                              GCancellable        *cancellable,
+                                              GAsyncReadyCallback  callback,
+                                              gpointer             user_data)
+{
+	JsonNode *json_compat_ids;
+	const gchar *version;
+	g_autofree gchar *cachefn_basename = NULL;
+	g_autofree gchar *cachefn = NULL;
+	g_autofree gchar *request_body = NULL;
+	g_autofree gchar *uri = NULL;
+	g_autoptr(GFile) cachefn_file = NULL;
+	g_autoptr(GPtrArray) reviews = NULL;
+	g_autoptr(JsonBuilder) builder = NULL;
+	g_autoptr(JsonParser) json_parser = NULL;
+	g_autoptr(JsonGenerator) json_generator = NULL;
+	g_autoptr(JsonNode) json_root = NULL;
+	g_autoptr(SoupMessage) msg = NULL;
+#if SOUP_CHECK_VERSION(3, 0, 0)
+	g_autoptr(GBytes) bytes = NULL;
+#endif
+	g_autoptr(GTask) task = NULL;
+	FetchReviewsForAppData *data;
+	g_autoptr(FetchReviewsForAppData) data_owned = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	task = g_task_new (self, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_odrs_provider_fetch_reviews_for_app_async);
+
+	data = data_owned = g_new0 (FetchReviewsForAppData, 1);
+	data->app = g_object_ref (app);
+	g_task_set_task_data (task, g_steal_pointer (&data_owned), (GDestroyNotify) fetch_reviews_for_app_data_free);
+
+	/* look in the cache */
+	cachefn_basename = g_strdup_printf ("%s.json", gs_app_get_id (app));
+	cachefn = gs_utils_get_cache_filename ("odrs",
+					       cachefn_basename,
+					       GS_UTILS_CACHE_FLAG_WRITEABLE |
+					       GS_UTILS_CACHE_FLAG_CREATE_DIRECTORY,
+					       &local_error);
+	if (cachefn == NULL) {
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	data->cache_filename = g_strdup (cachefn);
+	cachefn_file = g_file_new_for_path (cachefn);
+	if (gs_utils_get_file_age (cachefn_file) < self->max_cache_age_secs) {
+		g_debug ("got review data for %s from %s",
+			 gs_app_get_id (app), cachefn);
+
+		/* parse the data and find the array of ratings */
+		json_parser = json_parser_new_immutable ();
+		if (!json_parser_load_from_mapped_file (json_parser, cachefn, &local_error)) {
+			g_task_return_new_error (task,
+						 GS_ODRS_PROVIDER_ERROR,
+						 GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+						 "Error parsing ODRS data: %s", local_error->message);
+			return;
+		}
+
+		reviews = gs_odrs_provider_parse_reviews (self, json_parser, &local_error);
+		if (reviews == NULL) {
+			g_task_return_error (task, g_steal_pointer (&local_error));
+		} else {
+			set_reviews_on_app (self, app, reviews);
+			g_task_return_boolean (task, TRUE);
+		}
+
+		return;
+	}
+
+	/* not always available */
+	version = gs_app_get_version (app);
+	if (version == NULL)
+		version = "unknown";
+
+	/* create object with review data */
+	builder = json_builder_new ();
+	json_builder_begin_object (builder);
+	json_builder_set_member_name (builder, "user_hash");
+	json_builder_add_string_value (builder, self->user_hash);
+	json_builder_set_member_name (builder, "app_id");
+	json_builder_add_string_value (builder, gs_app_get_id (app));
+	json_builder_set_member_name (builder, "locale");
+	json_builder_add_string_value (builder, setlocale (LC_MESSAGES, NULL));
+	json_builder_set_member_name (builder, "distro");
+	json_builder_add_string_value (builder, self->distro);
+	json_builder_set_member_name (builder, "version");
+	json_builder_add_string_value (builder, version);
+	json_builder_set_member_name (builder, "limit");
+	json_builder_add_int_value (builder, self->n_results_max);
+	json_compat_ids = gs_odrs_provider_get_compat_ids (app);
+	if (json_compat_ids != NULL) {
+		json_builder_set_member_name (builder, "compat_ids");
+		json_builder_add_value (builder, json_compat_ids);
+	}
+	json_builder_end_object (builder);
+
+	/* export as a string */
+	json_root = json_builder_get_root (builder);
+	json_generator = json_generator_new ();
+	json_generator_set_pretty (json_generator, TRUE);
+	json_generator_set_root (json_generator, json_root);
+	request_body = json_generator_to_data (json_generator, NULL);
+
+	uri = g_strdup_printf ("%s/fetch", self->review_server);
+	g_debug ("Updating ODRS cache for %s from %s to %s; request %s", gs_app_get_id (app),
+		 uri, cachefn, request_body);
+	msg = soup_message_new (SOUP_METHOD_POST, uri);
+	data->message = g_object_ref (msg);
+
+#if SOUP_CHECK_VERSION(3, 0, 0)
+	g_odrs_provider_set_message_request_body (msg, "application/json; charset=utf-8",
+						  request_body, strlen (request_body));
+	soup_session_send_async (self->session, msg, G_PRIORITY_DEFAULT,
+				 cancellable, open_input_stream_cb, g_steal_pointer (&task));
+#else
+	soup_message_set_request (msg, "application/json; charset=utf-8",
+				  SOUP_MEMORY_COPY, request_body, strlen (request_body));
+	soup_session_send_async (self->session, msg, cancellable,
+				 open_input_stream_cb, g_steal_pointer (&task));
+#endif
+}
+
+static void
+open_input_stream_cb (GObject      *source_object,
+                      GAsyncResult *result,
+                      gpointer      user_data)
+{
+	SoupSession *soup_session = SOUP_SESSION (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	FetchReviewsForAppData *data = g_task_get_task_data (task);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+	g_autoptr(GInputStream) input_stream = NULL;
+	guint status_code;
+	g_autoptr(JsonParser) json_parser = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+#if SOUP_CHECK_VERSION(3, 0, 0)
+	input_stream = soup_session_send_finish (soup_session, result, &local_error);
+	status_code = soup_message_get_status (data->message);
+#else
+	input_stream = soup_session_send_finish (soup_session, result, &local_error);
+	status_code = data->message->status_code;
+#endif
+
+	if (input_stream == NULL) {
+		if (!g_network_monitor_get_network_available (g_network_monitor_get_default ()))
+			g_task_return_new_error (task,
+						 GS_ODRS_PROVIDER_ERROR,
+						 GS_ODRS_PROVIDER_ERROR_NO_NETWORK,
+						 "server couldn't be reached");
+		else
+			g_task_return_new_error (task,
+						 GS_ODRS_PROVIDER_ERROR,
+						 GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+						 "server returned no data");
+		return;
+	}
+
+	if (status_code != SOUP_STATUS_OK) {
+		if (!gs_odrs_provider_parse_success (input_stream, &local_error)) {
+			g_task_return_error (task, g_steal_pointer (&local_error));
+			return;
+		}
+
+		/* not sure what to do here */
+		g_task_return_new_error (task,
+					 GS_ODRS_PROVIDER_ERROR,
+					 GS_ODRS_PROVIDER_ERROR_DOWNLOADING,
+					 "status code invalid");
+		return;
+	}
+
+	/* parse the data and find the array of ratings */
+	json_parser = json_parser_new_immutable ();
+	json_parser_load_from_stream_async (json_parser, input_stream, cancellable, parse_reviews_cb, g_steal_pointer (&task));
+}
+
+static void
+parse_reviews_cb (GObject      *source_object,
+                  GAsyncResult *result,
+                  gpointer      user_data)
+{
+	JsonParser *json_parser = JSON_PARSER (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	GsOdrsProvider *self = g_task_get_source_object (task);
+	FetchReviewsForAppData *data = g_task_get_task_data (task);
+	g_autoptr(GPtrArray) reviews = NULL;
+	g_autoptr(JsonGenerator) cache_generator = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	if (!json_parser_load_from_stream_finish (json_parser, result, &local_error)) {
+		g_task_return_new_error (task,
+					 GS_ODRS_PROVIDER_ERROR,
+					 GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+					 "Error parsing ODRS data: %s", local_error->message);
+		return;
+	}
+
+	reviews = gs_odrs_provider_parse_reviews (self, json_parser, &local_error);
+	if (reviews == NULL) {
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	/* save to the cache */
+	cache_generator = json_generator_new ();
+	json_generator_set_pretty (cache_generator, FALSE);
+	json_generator_set_root (cache_generator, json_parser_get_root (json_parser));
+
+	if (!json_generator_to_file (cache_generator, data->cache_filename, &local_error)) {
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	set_reviews_on_app (self, data->app, reviews);
+
+	/* success */
+	g_task_return_boolean (task, TRUE);
+}
+
+static void
+set_reviews_on_app (GsOdrsProvider *self,
+                    GsApp          *app,
+                    GPtrArray      *reviews)
+{
+	for (guint i = 0; i < reviews->len; i++) {
+		AsReview *review = g_ptr_array_index (reviews, i);
+
+		/* save this on the application object so we can use it for
+		 * submitting a new review */
+		if (i == 0) {
+			gs_app_set_metadata (app, "ODRS::user_skey",
+					     as_review_get_metadata_item (review, "user_skey"));
+		}
+
+		/* ignore invalid reviews */
+		if (as_review_get_rating (review) == 0)
+			continue;
+
+		/* the user_hash matches, so mark this as our own review */
+		if (g_strcmp0 (as_review_get_reviewer_id (review),
+			       self->user_hash) == 0) {
+			as_review_set_flags (review, AS_REVIEW_FLAG_SELF);
+		}
+		gs_app_add_review (app, review);
+	}
+}
+
+static gboolean
+gs_odrs_provider_fetch_reviews_for_app_finish (GsOdrsProvider  *self,
+                                               GAsyncResult    *result,
+                                               GError         **error)
+{
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+static gchar *
+gs_odrs_provider_trim_version (const gchar *version)
+{
+	gchar *str;
+	gchar *tmp;
+
+	/* nothing set */
+	if (version == NULL)
+		return g_strdup ("unknown");
+
+	/* remove epoch */
+	str = g_strrstr (version, ":");
+	if (str != NULL)
+		version = str + 1;
+
+	/* remove release */
+	tmp = g_strdup (version);
+	g_strdelimit (tmp, "-", '\0');
+
+	/* remove '+dfsg' suffix */
+	str = g_strstr_len (tmp, -1, "+dfsg");
+	if (str != NULL)
+		*str = '\0';
+
+	return tmp;
+}
+
+static gboolean
+gs_odrs_provider_invalidate_cache (AsReview *review, GError **error)
+{
+	g_autofree gchar *cachefn_basename = NULL;
+	g_autofree gchar *cachefn = NULL;
+	g_autoptr(GFile) cachefn_file = NULL;
+
+	/* look in the cache */
+	cachefn_basename = g_strdup_printf ("%s.json",
+					    as_review_get_metadata_item (review, "app_id"));
+	cachefn = gs_utils_get_cache_filename ("odrs",
+					       cachefn_basename,
+					       GS_UTILS_CACHE_FLAG_WRITEABLE |
+					       GS_UTILS_CACHE_FLAG_CREATE_DIRECTORY,
+					       error);
+	if (cachefn == NULL)
+		return FALSE;
+	cachefn_file = g_file_new_for_path (cachefn);
+	if (!g_file_query_exists (cachefn_file, NULL))
+		return TRUE;
+	return g_file_delete (cachefn_file, NULL, error);
+}
+
+static gboolean
+gs_odrs_provider_vote (GsOdrsProvider  *self,
+                       AsReview        *review,
+                       const gchar     *uri,
+		       GCancellable    *cancellable,
+                       GError         **error)
+{
+	const gchar *tmp;
+	g_autofree gchar *data = NULL;
+	g_autoptr(JsonBuilder) builder = NULL;
+	g_autoptr(JsonGenerator) json_generator = NULL;
+	g_autoptr(JsonNode) json_root = NULL;
+
+	/* create object with vote data */
+	builder = json_builder_new ();
+	json_builder_begin_object (builder);
+
+	json_builder_set_member_name (builder, "user_hash");
+	json_builder_add_string_value (builder, self->user_hash);
+	json_builder_set_member_name (builder, "user_skey");
+	json_builder_add_string_value (builder,
+				       as_review_get_metadata_item (review, "user_skey"));
+	json_builder_set_member_name (builder, "app_id");
+	json_builder_add_string_value (builder,
+				       as_review_get_metadata_item (review, "app_id"));
+	tmp = as_review_get_id (review);
+	if (tmp != NULL) {
+		gint64 review_id;
+		json_builder_set_member_name (builder, "review_id");
+		review_id = g_ascii_strtoll (tmp, NULL, 10);
+		json_builder_add_int_value (builder, review_id);
+	}
+	json_builder_end_object (builder);
+
+	/* export as a string */
+	json_root = json_builder_get_root (builder);
+	json_generator = json_generator_new ();
+	json_generator_set_pretty (json_generator, TRUE);
+	json_generator_set_root (json_generator, json_root);
+	data = json_generator_to_data (json_generator, NULL);
+	if (data == NULL)
+		return FALSE;
+
+	/* clear cache */
+	if (!gs_odrs_provider_invalidate_cache (review, error))
+		return FALSE;
+
+	/* send to server */
+	if (!gs_odrs_provider_json_post (self->session, uri, data, cancellable, error))
+		return FALSE;
+
+	/* mark as voted */
+	as_review_add_flags (review, AS_REVIEW_FLAG_VOTED);
+
+	/* success */
+	return TRUE;
+}
+
+static GsApp *
+gs_odrs_provider_create_app_dummy (const gchar *id)
+{
+	GsApp *app = gs_app_new (id);
+	g_autoptr(GString) str = NULL;
+	str = g_string_new (id);
+	as_gstring_replace (str, ".desktop", "");
+	g_string_prepend (str, "No description is available for ");
+	gs_app_set_name (app, GS_APP_QUALITY_LOWEST, "Unknown Application");
+	gs_app_set_summary (app, GS_APP_QUALITY_LOWEST, "Application not found");
+	gs_app_set_description (app, GS_APP_QUALITY_LOWEST, str->str);
+	return app;
+}
+
+static void
+gs_odrs_provider_init (GsOdrsProvider *self)
+{
+	g_mutex_init (&self->ratings_mutex);
+}
+
+static void
+gs_odrs_provider_constructed (GObject *object)
+{
+	GsOdrsProvider *self = GS_ODRS_PROVIDER (object);
+
+	G_OBJECT_CLASS (gs_odrs_provider_parent_class)->constructed (object);
+
+	/* Check all required properties have been set. */
+	g_assert (self->review_server != NULL);
+	g_assert (self->user_hash != NULL);
+	g_assert (self->distro != NULL);
+}
+
+static void
+gs_odrs_provider_get_property (GObject    *object,
+                               guint       prop_id,
+                               GValue     *value,
+                               GParamSpec *pspec)
+{
+	GsOdrsProvider *self = GS_ODRS_PROVIDER (object);
+
+	switch ((GsOdrsProviderProperty) prop_id) {
+	case PROP_REVIEW_SERVER:
+		g_value_set_string (value, self->review_server);
+		break;
+	case PROP_USER_HASH:
+		g_value_set_string (value, self->user_hash);
+		break;
+	case PROP_DISTRO:
+		g_value_set_string (value, self->distro);
+		break;
+	case PROP_MAX_CACHE_AGE_SECS:
+		g_value_set_uint64 (value, self->max_cache_age_secs);
+		break;
+	case PROP_N_RESULTS_MAX:
+		g_value_set_uint (value, self->n_results_max);
+		break;
+	case PROP_SESSION:
+		g_value_set_object (value, self->session);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_odrs_provider_set_property (GObject      *object,
+                               guint         prop_id,
+                               const GValue *value,
+                               GParamSpec   *pspec)
+{
+	GsOdrsProvider *self = GS_ODRS_PROVIDER (object);
+
+	switch ((GsOdrsProviderProperty) prop_id) {
+	case PROP_REVIEW_SERVER:
+		/* Construct-only */
+		g_assert (self->review_server == NULL);
+		self->review_server = g_value_dup_string (value);
+		break;
+	case PROP_USER_HASH:
+		/* Construct-only */
+		g_assert (self->user_hash == NULL);
+		self->user_hash = g_value_dup_string (value);
+		break;
+	case PROP_DISTRO:
+		/* Construct-only */
+		g_assert (self->distro == NULL);
+		self->distro = g_value_dup_string (value);
+		break;
+	case PROP_MAX_CACHE_AGE_SECS:
+		/* Construct-only */
+		g_assert (self->max_cache_age_secs == 0);
+		self->max_cache_age_secs = g_value_get_uint64 (value);
+		break;
+	case PROP_N_RESULTS_MAX:
+		/* Construct-only */
+		g_assert (self->n_results_max == 0);
+		self->n_results_max = g_value_get_uint (value);
+		break;
+	case PROP_SESSION:
+		/* Construct-only */
+		g_assert (self->session == NULL);
+		self->session = g_value_dup_object (value);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_odrs_provider_dispose (GObject *object)
+{
+	GsOdrsProvider *self = GS_ODRS_PROVIDER (object);
+
+	g_clear_object (&self->session);
+
+	G_OBJECT_CLASS (gs_odrs_provider_parent_class)->dispose (object);
+}
+
+static void
+gs_odrs_provider_finalize (GObject *object)
+{
+	GsOdrsProvider *self = GS_ODRS_PROVIDER (object);
+
+	g_free (self->user_hash);
+	g_free (self->distro);
+	g_free (self->review_server);
+	g_clear_pointer (&self->ratings, g_array_unref);
+	g_mutex_clear (&self->ratings_mutex);
+
+	G_OBJECT_CLASS (gs_odrs_provider_parent_class)->finalize (object);
+}
+
+static void
+gs_odrs_provider_class_init (GsOdrsProviderClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+	object_class->constructed = gs_odrs_provider_constructed;
+	object_class->get_property = gs_odrs_provider_get_property;
+	object_class->set_property = gs_odrs_provider_set_property;
+	object_class->dispose = gs_odrs_provider_dispose;
+	object_class->finalize = gs_odrs_provider_finalize;
+
+	/**
+	 * GsOdrsProvider:review-server: (not nullable)
+	 *
+	 * The URI of the ODRS review server to contact.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_REVIEW_SERVER] =
+		g_param_spec_string ("review-server", NULL, NULL,
+				     NULL,
+				     G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS | G_PARAM_CONSTRUCT_ONLY);
+
+	/**
+	 * GsOdrsProvider:user-hash: (not nullable)
+	 *
+	 * An opaque hash of the user identifier, used to identify the user on
+	 * the server.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_USER_HASH] =
+		g_param_spec_string ("user-hash", NULL, NULL,
+				     NULL,
+				     G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS | G_PARAM_CONSTRUCT_ONLY);
+
+	/**
+	 * GsOdrsProvider:distro: (not nullable)
+	 *
+	 * A human readable string identifying the current distribution.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_DISTRO] =
+		g_param_spec_string ("distro", NULL, NULL,
+				     NULL,
+				     G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS | G_PARAM_CONSTRUCT_ONLY);
+
+	/**
+	 * GsOdrsProvider:max-cache-age-secs:
+	 *
+	 * The maximum age of the ODRS cache files, in seconds. Older files will
+	 * be refreshed on demand.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_MAX_CACHE_AGE_SECS] =
+		g_param_spec_uint64 ("max-cache-age-secs", NULL, NULL,
+				     0, G_MAXUINT64, 0,
+				     G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS | G_PARAM_CONSTRUCT_ONLY);
+
+	/**
+	 * GsOdrsProvider:n-results-max:
+	 *
+	 * Maximum number of reviews or ratings to download. The default value
+	 * of 0 means no limit is applied.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_N_RESULTS_MAX] =
+		g_param_spec_uint ("n-results-max", NULL, NULL,
+				   0, G_MAXUINT, 0,
+				   G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS | G_PARAM_CONSTRUCT_ONLY);
+
+	/**
+	 * GsOdrsProvider:session: (not nullable)
+	 *
+	 * #SoupSession to use for downloading things.
+	 *
+	 * Since: 41
+	 */
+	obj_props[PROP_SESSION] =
+		g_param_spec_object ("session", NULL, NULL,
+				     SOUP_TYPE_SESSION,
+				     G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS | G_PARAM_CONSTRUCT_ONLY);
+
+	g_object_class_install_properties (object_class, G_N_ELEMENTS (obj_props), obj_props);
+}
+
+/**
+ * gs_odrs_provider_new:
+ * @review_server: (not nullable): value for #GsOdrsProvider:review-server
+ * @user_hash: (not nullable): value for #GsOdrsProvider:user-hash
+ * @distro: (not nullable): value for #GsOdrsProvider:distro
+ * @max_cache_age_secs: value for #GsOdrsProvider:max-cache-age-secs
+ * @n_results_max: value for #GsOdrsProvider:n-results-max
+ * @session: value for #GsOdrsProvider:session
+ *
+ * Create a new #GsOdrsProvider. This does no network activity.
+ *
+ * Returns: (transfer full): a new #GsOdrsProvider
+ * Since: 41
+ */
+GsOdrsProvider *
+gs_odrs_provider_new (const gchar *review_server,
+                      const gchar *user_hash,
+                      const gchar *distro,
+                      guint64      max_cache_age_secs,
+                      guint        n_results_max,
+                      SoupSession *session)
+{
+	g_return_val_if_fail (review_server != NULL && *review_server != '\0', NULL);
+	g_return_val_if_fail (user_hash != NULL && *user_hash != '\0', NULL);
+	g_return_val_if_fail (distro != NULL && *distro != '\0', NULL);
+	g_return_val_if_fail (SOUP_IS_SESSION (session), NULL);
+
+	return g_object_new (GS_TYPE_ODRS_PROVIDER,
+			     "review-server", review_server,
+			     "user-hash", user_hash,
+			     "distro", distro,
+			     "max-cache-age-secs", max_cache_age_secs,
+			     "n-results-max", n_results_max,
+			     "session", session,
+			     NULL);
+}
+
+static void download_ratings_cb (GObject      *source_object,
+                                 GAsyncResult *result,
+                                 gpointer      user_data);
+
+/**
+ * gs_odrs_provider_refresh_ratings_async:
+ * @self: a #GsOdrsProvider
+ * @cache_age_secs: cache age, in seconds, as passed to #GsPluginClass.refresh_metadata_async()
+ * @progress_callback: (nullable): callback to call with progress information
+ * @progress_user_data: (nullable) (closure progress_callback): data to pass
+ *   to @progress_callback
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @callback: function to call when the asynchronous operation is complete
+ * @user_data: data to pass to @callback
+ *
+ * Refresh the cached ODRS ratings and re-load them asynchronously.
+ *
+ * Since: 42
+ */
+void
+gs_odrs_provider_refresh_ratings_async (GsOdrsProvider             *self,
+                                        guint64                     cache_age_secs,
+                                        GsDownloadProgressCallback  progress_callback,
+                                        gpointer                    progress_user_data,
+                                        GCancellable               *cancellable,
+                                        GAsyncReadyCallback         callback,
+                                        gpointer                    user_data)
+{
+	g_autofree gchar *cache_filename = NULL;
+	g_autoptr(GFile) cache_file = NULL;
+	g_autofree gchar *uri = NULL;
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GTask) task = NULL;
+
+	task = g_task_new (self, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_odrs_provider_refresh_ratings_async);
+
+	/* check cache age */
+	cache_filename = gs_utils_get_cache_filename ("odrs",
+						      "ratings.json",
+						      GS_UTILS_CACHE_FLAG_WRITEABLE |
+						      GS_UTILS_CACHE_FLAG_CREATE_DIRECTORY,
+						      &error_local);
+	if (cache_filename == NULL) {
+		g_task_return_error (task, g_steal_pointer (&error_local));
+		return;
+	}
+
+	cache_file = g_file_new_for_path (cache_filename);
+	g_task_set_task_data (task, g_object_ref (cache_file), g_object_unref);
+
+	if (cache_age_secs > 0) {
+		guint64 tmp;
+
+		tmp = gs_utils_get_file_age (cache_file);
+		if (tmp < cache_age_secs) {
+			g_debug ("%s is only %" G_GUINT64_FORMAT " seconds old, so ignoring refresh",
+				 cache_filename, tmp);
+			if (!gs_odrs_provider_load_ratings (self, cache_filename, &error_local)) {
+				g_debug ("Failed to load cache file ‘%s’, deleting it", cache_filename);
+				g_file_delete (cache_file, NULL, NULL);
+
+				g_task_return_error (task, g_steal_pointer (&error_local));
+			} else {
+				g_task_return_boolean (task, TRUE);
+			}
+			return;
+		}
+	}
+
+	/* download the complete file */
+	uri = g_strdup_printf ("%s/ratings", self->review_server);
+	g_debug ("Updating ODRS cache from %s to %s", uri, cache_filename);
+
+	gs_download_file_async (self->session, uri, cache_file, G_PRIORITY_LOW,
+				progress_callback, progress_user_data,
+				cancellable, download_ratings_cb, g_steal_pointer (&task));
+}
+
+static void
+download_ratings_cb (GObject      *source_object,
+                     GAsyncResult *result,
+                     gpointer      user_data)
+{
+	SoupSession *soup_session = SOUP_SESSION (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	GsOdrsProvider *self = g_task_get_source_object (task);
+	GFile *cache_file = g_task_get_task_data (task);
+	const gchar *cache_file_path = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	if (!gs_download_file_finish (soup_session, result, &local_error) &&
+	    !g_error_matches (local_error, GS_DOWNLOAD_ERROR, GS_DOWNLOAD_ERROR_NOT_MODIFIED)) {
+		g_task_return_new_error (task, GS_ODRS_PROVIDER_ERROR,
+					 GS_ODRS_PROVIDER_ERROR_DOWNLOADING,
+					 "%s", local_error->message);
+		return;
+	}
+
+	g_clear_error (&local_error);
+
+	cache_file_path = g_file_peek_path (cache_file);
+	if (!gs_odrs_provider_load_ratings (self, cache_file_path, &local_error)) {
+		g_debug ("Failed to load cache file ‘%s’, deleting it", cache_file_path);
+		g_file_delete (cache_file, NULL, NULL);
+
+		g_task_return_new_error (task, GS_ODRS_PROVIDER_ERROR,
+					 GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+					 "%s", local_error->message);
+	} else {
+		g_task_return_boolean (task, TRUE);
+	}
+}
+
+/**
+ * gs_odrs_provider_refresh_ratings_finish:
+ * @self: a #GsOdrsProvider
+ * @result: result of the asynchronous operation
+ * @error: return location for a #GError, or %NULL
+ *
+ * Finish an asynchronous refresh operation started with
+ * gs_odrs_provider_refresh_ratings_async().
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 42
+ */
+gboolean
+gs_odrs_provider_refresh_ratings_finish (GsOdrsProvider  *self,
+                                         GAsyncResult    *result,
+                                         GError         **error)
+{
+	g_return_val_if_fail (GS_IS_ODRS_PROVIDER (self), FALSE);
+	g_return_val_if_fail (g_task_is_valid (result, self), FALSE);
+	g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gs_odrs_provider_refresh_ratings_async, FALSE);
+	g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
+
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+static void refine_app_op (GsOdrsProvider            *self,
+                           GTask                     *task,
+                           GsApp                     *app,
+                           GsOdrsProviderRefineFlags  flags,
+                           GCancellable              *cancellable);
+static void refine_reviews_cb (GObject      *source_object,
+                               GAsyncResult *result,
+                               gpointer      user_data);
+static void finish_refine_op (GTask  *task,
+                              GError *error);
+
+typedef struct {
+	/* Input data. */
+	GsAppList *list;  /* (owned) (not nullable) */
+	GsOdrsProviderRefineFlags flags;
+
+	/* In-progress data. */
+	guint n_pending_ops;
+	GError *error;  /* (nullable) (owned) */
+} RefineData;
+
+static void
+refine_data_free (RefineData *data)
+{
+	g_assert (data->n_pending_ops == 0);
+
+	g_clear_object (&data->list);
+	g_clear_error (&data->error);
+
+	g_free (data);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (RefineData, refine_data_free)
+
+/**
+ * gs_odrs_provider_refine_async:
+ * @self: a #GsOdrsProvider
+ * @list: list of apps to refine
+ * @flags: refine flags
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @callback: callback for asynchronous completion
+ * @user_data: data to pass to @callback
+ *
+ * Asynchronously refine the given @list of apps to add ratings and review data
+ * to them, as specified in @flags.
+ *
+ * Since: 42
+ */
+void
+gs_odrs_provider_refine_async (GsOdrsProvider            *self,
+                               GsAppList                 *list,
+                               GsOdrsProviderRefineFlags  flags,
+                               GCancellable              *cancellable,
+                               GAsyncReadyCallback        callback,
+                               gpointer                   user_data)
+{
+	g_autoptr(GTask) task = NULL;
+	g_autoptr(RefineData) data = NULL;
+	RefineData *data_unowned = NULL;
+
+	task = g_task_new (self, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_odrs_provider_refine_async);
+
+	data_unowned = data = g_new0 (RefineData, 1);
+	data->list = g_object_ref (list);
+	data->flags = flags;
+	g_task_set_task_data (task, g_steal_pointer (&data), (GDestroyNotify) refine_data_free);
+
+	if ((flags & (GS_ODRS_PROVIDER_REFINE_FLAGS_GET_RATINGS |
+		      GS_ODRS_PROVIDER_REFINE_FLAGS_GET_REVIEWS)) == 0) {
+		g_task_return_boolean (task, TRUE);
+		return;
+	}
+
+	/* Mark one operation as pending while all the operations are started,
+	 * so the overall operation can’t complete while things are still being
+	 * started. */
+	data_unowned->n_pending_ops++;
+
+	for (guint i = 0; i < gs_app_list_length (list); i++) {
+		GsApp *app = gs_app_list_index (list, i);
+
+		/* not valid */
+		if (gs_app_get_kind (app) == AS_COMPONENT_KIND_ADDON)
+			continue;
+		if (gs_app_get_id (app) == NULL)
+			continue;
+
+		data_unowned->n_pending_ops++;
+		refine_app_op (self, task, app, flags, cancellable);
+	}
+
+	finish_refine_op (task, NULL);
+}
+
+static void
+refine_app_op (GsOdrsProvider            *self,
+               GTask                     *task,
+               GsApp                     *app,
+               GsOdrsProviderRefineFlags  flags,
+               GCancellable              *cancellable)
+{
+	g_autoptr(GError) local_error = NULL;
+
+	/* add ratings if possible */
+	if ((flags & GS_ODRS_PROVIDER_REFINE_FLAGS_GET_RATINGS) &&
+	    gs_app_get_review_ratings (app) == NULL) {
+		if (!gs_odrs_provider_refine_ratings (self, app, cancellable, &local_error)) {
+			if (g_error_matches (local_error, GS_ODRS_PROVIDER_ERROR, GS_ODRS_PROVIDER_ERROR_NO_NETWORK)) {
+				g_debug ("failed to refine app %s: %s",
+					 gs_app_get_unique_id (app), local_error->message);
+			} else {
+				g_prefix_error (&local_error, "failed to refine app: ");
+				finish_refine_op (task, g_steal_pointer (&local_error));
+				return;
+			}
+		}
+	}
+
+	/* add reviews if possible */
+	if ((flags & GS_ODRS_PROVIDER_REFINE_FLAGS_GET_REVIEWS) &&
+	    gs_app_get_reviews (app)->len == 0) {
+		/* get from server asynchronously */
+		gs_odrs_provider_fetch_reviews_for_app_async (self, app, cancellable, refine_reviews_cb, g_object_ref (task));
+	} else {
+		finish_refine_op (task, NULL);
+	}
+}
+
+static void
+refine_reviews_cb (GObject      *source_object,
+                   GAsyncResult *result,
+                   gpointer      user_data)
+{
+	GsOdrsProvider *self = GS_ODRS_PROVIDER (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	g_autoptr(GError) local_error = NULL;
+
+	if (!gs_odrs_provider_fetch_reviews_for_app_finish (self, result, &local_error)) {
+		if (g_error_matches (local_error, GS_ODRS_PROVIDER_ERROR, GS_ODRS_PROVIDER_ERROR_NO_NETWORK)) {
+			g_debug ("failed to refine app: %s", local_error->message);
+		} else {
+			g_prefix_error (&local_error, "failed to refine app: ");
+			finish_refine_op (task, g_steal_pointer (&local_error));
+			return;
+		}
+	}
+
+	finish_refine_op (task, NULL);
+}
+
+/* @error is (transfer full) if non-NULL. */
+static void
+finish_refine_op (GTask  *task,
+                  GError *error)
+{
+	RefineData *data = g_task_get_task_data (task);
+	g_autoptr(GError) error_owned = g_steal_pointer (&error);
+
+	if (data->error == NULL && error_owned != NULL)
+		data->error = g_steal_pointer (&error_owned);
+	else if (error_owned != NULL)
+		g_debug ("Additional error while refining ODRS data: %s", error_owned->message);
+
+	g_assert (data->n_pending_ops > 0);
+	data->n_pending_ops--;
+
+	if (data->n_pending_ops == 0) {
+		if (data->error != NULL)
+			g_task_return_error (task, g_steal_pointer (&data->error));
+		else
+			g_task_return_boolean (task, TRUE);
+	}
+}
+
+/**
+ * gs_odrs_provider_refine_finish:
+ * @self: a #GsOdrsProvider
+ * @result: result of the asynchronous operation
+ * @error: return location for a #GError, or %NULL
+ *
+ * Finish an asynchronous refine operation started with
+ * gs_odrs_provider_refine_finish().
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 42
+ */
+gboolean
+gs_odrs_provider_refine_finish (GsOdrsProvider  *self,
+                                GAsyncResult    *result,
+                                GError         **error)
+{
+	g_return_val_if_fail (GS_IS_ODRS_PROVIDER (self), FALSE);
+	g_return_val_if_fail (g_task_is_valid (result, self), FALSE);
+	g_return_val_if_fail (g_async_result_is_tagged (result, gs_odrs_provider_refine_async), FALSE);
+	g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
+
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+/**
+ * gs_odrs_provider_submit_review:
+ * @self: a #GsOdrsProvider
+ * @app: the app being reviewed
+ * @review: the review
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @error: return location for a #GError
+ *
+ * Submit a new @review for @app.
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 41
+ */
+gboolean
+gs_odrs_provider_submit_review (GsOdrsProvider  *self,
+                                GsApp           *app,
+                                AsReview        *review,
+                                GCancellable    *cancellable,
+                                GError         **error)
+{
+	g_autofree gchar *data = NULL;
+	g_autofree gchar *uri = NULL;
+	g_autofree gchar *version = NULL;
+	g_autoptr(JsonBuilder) builder = NULL;
+	g_autoptr(JsonGenerator) json_generator = NULL;
+	g_autoptr(JsonNode) json_root = NULL;
+
+	/* save as we don't re-request the review from the server */
+	as_review_add_flags (review, AS_REVIEW_FLAG_SELF);
+	as_review_set_reviewer_name (review, g_get_real_name ());
+	as_review_add_metadata (review, "app_id", gs_app_get_id (app));
+	as_review_add_metadata (review, "user_skey",
+				gs_app_get_metadata_item (app, "ODRS::user_skey"));
+
+	/* create object with review data */
+	builder = json_builder_new ();
+	json_builder_begin_object (builder);
+	json_builder_set_member_name (builder, "user_hash");
+	json_builder_add_string_value (builder, self->user_hash);
+	json_builder_set_member_name (builder, "user_skey");
+	json_builder_add_string_value (builder,
+				       as_review_get_metadata_item (review, "user_skey"));
+	json_builder_set_member_name (builder, "app_id");
+	json_builder_add_string_value (builder,
+				       as_review_get_metadata_item (review, "app_id"));
+	json_builder_set_member_name (builder, "locale");
+	json_builder_add_string_value (builder, setlocale (LC_MESSAGES, NULL));
+	json_builder_set_member_name (builder, "distro");
+	json_builder_add_string_value (builder, self->distro);
+	json_builder_set_member_name (builder, "version");
+	version = gs_odrs_provider_trim_version (as_review_get_version (review));
+	json_builder_add_string_value (builder, version);
+	json_builder_set_member_name (builder, "user_display");
+	json_builder_add_string_value (builder, as_review_get_reviewer_name (review));
+	json_builder_set_member_name (builder, "summary");
+	json_builder_add_string_value (builder, as_review_get_summary (review));
+	json_builder_set_member_name (builder, "description");
+	json_builder_add_string_value (builder, as_review_get_description (review));
+	json_builder_set_member_name (builder, "rating");
+	json_builder_add_int_value (builder, as_review_get_rating (review));
+	json_builder_end_object (builder);
+
+	/* export as a string */
+	json_root = json_builder_get_root (builder);
+	json_generator = json_generator_new ();
+	json_generator_set_pretty (json_generator, TRUE);
+	json_generator_set_root (json_generator, json_root);
+	data = json_generator_to_data (json_generator, NULL);
+
+	/* clear cache */
+	if (!gs_odrs_provider_invalidate_cache (review, error))
+		return FALSE;
+
+	/* POST */
+	uri = g_strdup_printf ("%s/submit", self->review_server);
+	if (!gs_odrs_provider_json_post (self->session, uri, data, cancellable, error))
+		return FALSE;
+
+	/* modify the local app */
+	gs_app_add_review (app, review);
+
+	return TRUE;
+}
+
+/**
+ * gs_odrs_provider_report_review:
+ * @self: a #GsOdrsProvider
+ * @app: the app whose review is being reported
+ * @review: the review to report
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @error: return location for a #GError
+ *
+ * Report the given @review on @app for being incorrect or breaking the code of
+ * conduct.
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 41
+ */
+gboolean
+gs_odrs_provider_report_review (GsOdrsProvider  *self,
+                                GsApp           *app,
+                                AsReview        *review,
+                                GCancellable    *cancellable,
+                                GError         **error)
+{
+	g_autofree gchar *uri = NULL;
+	uri = g_strdup_printf ("%s/report", self->review_server);
+	return gs_odrs_provider_vote (self, review, uri, cancellable, error);
+}
+
+/**
+ * gs_odrs_provider_upvote_review:
+ * @self: a #GsOdrsProvider
+ * @app: the app whose review is being upvoted
+ * @review: the review to upvote
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @error: return location for a #GError
+ *
+ * Add one vote to @review on @app.
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 41
+ */
+gboolean
+gs_odrs_provider_upvote_review (GsOdrsProvider  *self,
+                                GsApp           *app,
+                                AsReview        *review,
+                                GCancellable    *cancellable,
+                                GError         **error)
+{
+	g_autofree gchar *uri = NULL;
+	uri = g_strdup_printf ("%s/upvote", self->review_server);
+	return gs_odrs_provider_vote (self, review, uri, cancellable, error);
+}
+
+/**
+ * gs_odrs_provider_downvote_review:
+ * @self: a #GsOdrsProvider
+ * @app: the app whose review is being downvoted
+ * @review: the review to downvote
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @error: return location for a #GError
+ *
+ * Remove one vote from @review on @app.
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 41
+ */
+gboolean
+gs_odrs_provider_downvote_review (GsOdrsProvider  *self,
+                                  GsApp           *app,
+                                  AsReview        *review,
+                                  GCancellable    *cancellable,
+                                  GError         **error)
+{
+	g_autofree gchar *uri = NULL;
+	uri = g_strdup_printf ("%s/downvote", self->review_server);
+	return gs_odrs_provider_vote (self, review, uri, cancellable, error);
+}
+
+/**
+ * gs_odrs_provider_dismiss_review:
+ * @self: a #GsOdrsProvider
+ * @app: the app whose review is being dismissed
+ * @review: the review to dismiss
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @error: return location for a #GError
+ *
+ * Dismiss (ignore) @review on @app when moderating.
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 41
+ */
+gboolean
+gs_odrs_provider_dismiss_review (GsOdrsProvider  *self,
+                                 GsApp           *app,
+                                 AsReview        *review,
+                                 GCancellable    *cancellable,
+                                 GError         **error)
+{
+	g_autofree gchar *uri = NULL;
+	uri = g_strdup_printf ("%s/dismiss", self->review_server);
+	return gs_odrs_provider_vote (self, review, uri, cancellable, error);
+}
+
+/**
+ * gs_odrs_provider_remove_review:
+ * @self: a #GsOdrsProvider
+ * @app: the app whose review is being removed
+ * @review: the review to remove
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @error: return location for a #GError
+ *
+ * Remove a @review written by the user, from @app.
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 41
+ */
+gboolean
+gs_odrs_provider_remove_review (GsOdrsProvider  *self,
+                                GsApp           *app,
+                                AsReview        *review,
+                                GCancellable    *cancellable,
+                                GError         **error)
+{
+	g_autofree gchar *uri = NULL;
+	uri = g_strdup_printf ("%s/remove", self->review_server);
+	if (!gs_odrs_provider_vote (self, review, uri, cancellable, error))
+		return FALSE;
+
+	/* update the local app */
+	gs_app_remove_review (app, review);
+
+	return TRUE;
+}
+
+/**
+ * gs_odrs_provider_add_unvoted_reviews:
+ * @self: a #GsOdrsProvider
+ * @list: list of apps to add unvoted reviews to
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @error: return location for a #GError
+ *
+ * Add the unmoderated reviews for each app in @list to the apps.
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 41
+ */
+gboolean
+gs_odrs_provider_add_unvoted_reviews (GsOdrsProvider  *self,
+                                      GsAppList       *list,
+                                      GCancellable    *cancellable,
+                                      GError         **error)
+{
+	guint status_code;
+	guint i;
+	gconstpointer downloaded_data;
+	gsize downloaded_data_length;
+	g_autofree gchar *uri = NULL;
+	g_autoptr(GHashTable) hash = NULL;
+	g_autoptr(JsonParser) json_parser = NULL;
+	g_autoptr(GPtrArray) reviews = NULL;
+	g_autoptr(SoupMessage) msg = NULL;
+#if SOUP_CHECK_VERSION(3, 0, 0)
+	g_autoptr(GBytes) bytes = NULL;
+#endif
+	g_autoptr(GError) local_error = NULL;
+
+	/* create the GET data *with* the machine hash so we can later
+	 * review the application ourselves */
+	uri = g_strdup_printf ("%s/moderate/%s/%s",
+			       self->review_server,
+			       self->user_hash,
+			       setlocale (LC_MESSAGES, NULL));
+	msg = soup_message_new (SOUP_METHOD_GET, uri);
+#if SOUP_CHECK_VERSION(3, 0, 0)
+	bytes = soup_session_send_and_read (self->session, msg, cancellable, error);
+	if (bytes == NULL)
+		return FALSE;
+
+	downloaded_data = g_bytes_get_data (bytes, &downloaded_data_length);
+	status_code = soup_message_get_status (msg);
+#else
+	status_code = soup_session_send_message (self->session, msg);
+	downloaded_data = msg->response_body ? msg->response_body->data : NULL;
+	downloaded_data_length = msg->response_body ? msg->response_body->length : 0;
+#endif
+	if (status_code != SOUP_STATUS_OK) {
+		g_autoptr(GInputStream) input_stream = g_memory_input_stream_new_from_data (downloaded_data, downloaded_data_length, NULL);
+		if (!gs_odrs_provider_parse_success (input_stream, error))
+			return FALSE;
+		/* not sure what to do here */
+		g_set_error_literal (error,
+				     GS_ODRS_PROVIDER_ERROR,
+				     GS_ODRS_PROVIDER_ERROR_DOWNLOADING,
+				     "status code invalid");
+		return FALSE;
+	}
+	g_debug ("odrs returned: %.*s", (gint) downloaded_data_length, (const gchar *) downloaded_data);
+
+	/* nothing */
+	if (downloaded_data == NULL) {
+		if (!g_network_monitor_get_network_available (g_network_monitor_get_default ()))
+			g_set_error_literal (error,
+					     GS_ODRS_PROVIDER_ERROR,
+					     GS_ODRS_PROVIDER_ERROR_NO_NETWORK,
+					     "server couldn't be reached");
+		else
+			g_set_error_literal (error,
+					     GS_ODRS_PROVIDER_ERROR,
+					     GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+					     "server returned no data");
+		return FALSE;
+	}
+
+	/* parse the data and find the array of ratings */
+	json_parser = json_parser_new_immutable ();
+	if (!json_parser_load_from_data (json_parser, downloaded_data, downloaded_data_length, &local_error)) {
+		g_set_error (error,
+			     GS_ODRS_PROVIDER_ERROR,
+			     GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+			     "Error parsing ODRS data: %s", local_error->message);
+		return FALSE;
+	}
+
+	reviews = gs_odrs_provider_parse_reviews (self, json_parser, error);
+	if (reviews == NULL)
+		return FALSE;
+
+	/* look at all the reviews; faking application objects */
+	hash = g_hash_table_new_full (g_str_hash, g_str_equal,
+				      g_free, g_object_unref);
+	for (i = 0; i < reviews->len; i++) {
+		GsApp *app;
+		AsReview *review;
+		const gchar *app_id;
+
+		/* same app? */
+		review = g_ptr_array_index (reviews, i);
+		app_id = as_review_get_metadata_item (review, "app_id");
+		app = g_hash_table_lookup (hash, app_id);
+		if (app == NULL) {
+			app = gs_odrs_provider_create_app_dummy (app_id);
+			gs_app_list_add (list, app);
+			g_hash_table_insert (hash, g_strdup (app_id), app);
+		}
+		gs_app_add_review (app, review);
+	}
+
+	return TRUE;
+}
diff --git a/lib/gs-odrs-provider.h b/lib/gs-odrs-provider.h
new file mode 100644
index 0000000..f02ffde
--- /dev/null
+++ b/lib/gs-odrs-provider.h
@@ -0,0 +1,125 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <glib-object.h>
+#include <libsoup/soup.h>
+
+#include "gs-app-list.h"
+#include "gs-download-utils.h"
+
+G_BEGIN_DECLS
+
+/**
+ * GsOdrsProviderError:
+ * @GS_ODRS_PROVIDER_ERROR_DOWNLOADING: Error while downloading ODRS data.
+ * @GS_ODRS_PROVIDER_ERROR_PARSING_DATA: Problem parsing downloaded ODRS data.
+ * @GS_ODRS_PROVIDER_ERROR_NO_NETWORK: Offline or network unavailable.
+ * @GS_ODRS_PROVIDER_ERROR_SERVER_ERROR: Server rejected ODRS submission or returned an error.
+ *
+ * Error codes for #GsOdrsProvider.
+ *
+ * Since: 42
+ */
+typedef enum {
+	GS_ODRS_PROVIDER_ERROR_DOWNLOADING,
+	GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+	GS_ODRS_PROVIDER_ERROR_NO_NETWORK,
+	GS_ODRS_PROVIDER_ERROR_SERVER_ERROR,
+} GsOdrsProviderError;
+
+#define GS_ODRS_PROVIDER_ERROR gs_odrs_provider_error_quark ()
+GQuark		 gs_odrs_provider_error_quark		(void);
+
+/**
+ * GsOdrsProviderRefineFlags:
+ * @GS_ODRS_PROVIDER_REFINE_FLAGS_GET_RATINGS: Get the numerical ratings for the app.
+ * @GS_ODRS_PROVIDER_REFINE_FLAGS_GET_REVIEWS: Get the written reviews for the app.
+ *
+ * The flags for refining apps to get their reviews or ratings.
+ *
+ * Since: 42
+ */
+typedef enum {
+	GS_ODRS_PROVIDER_REFINE_FLAGS_GET_RATINGS = (1 << 0),
+	GS_ODRS_PROVIDER_REFINE_FLAGS_GET_REVIEWS = (1 << 1),
+} GsOdrsProviderRefineFlags;
+
+#define GS_TYPE_ODRS_PROVIDER (gs_odrs_provider_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsOdrsProvider, gs_odrs_provider, GS, ODRS_PROVIDER, GObject)
+
+GsOdrsProvider	*gs_odrs_provider_new			(const gchar		 *review_server,
+							 const gchar		 *user_hash,
+							 const gchar		 *distro,
+							 guint64		  max_cache_age_secs,
+							 guint			  n_results_max,
+							 SoupSession		 *session);
+
+void		 gs_odrs_provider_refresh_ratings_async	(GsOdrsProvider		 *self,
+							 guint64		  cache_age_secs,
+							 GsDownloadProgressCallback progress_callback,
+							 gpointer		  progress_user_data,
+							 GCancellable		 *cancellable,
+							 GAsyncReadyCallback	  callback,
+							 gpointer		  user_data);
+gboolean	 gs_odrs_provider_refresh_ratings_finish(GsOdrsProvider		 *self,
+							 GAsyncResult		 *result,
+							 GError			**error);
+
+void		 gs_odrs_provider_refine_async		(GsOdrsProvider		 *self,
+							 GsAppList		 *list,
+							 GsOdrsProviderRefineFlags flags,
+							 GCancellable		 *cancellable,
+							 GAsyncReadyCallback	  callback,
+							 gpointer		  user_data);
+gboolean	 gs_odrs_provider_refine_finish		(GsOdrsProvider		 *self,
+							 GAsyncResult		 *result,
+							 GError			**error);
+
+gboolean	 gs_odrs_provider_submit_review		(GsOdrsProvider		 *self,
+							 GsApp			 *app,
+							 AsReview		 *review,
+							 GCancellable		 *cancellable,
+							 GError			**error);
+gboolean	 gs_odrs_provider_report_review		(GsOdrsProvider		 *self,
+							 GsApp			 *app,
+							 AsReview		 *review,
+							 GCancellable		 *cancellable,
+							 GError			**error);
+gboolean	 gs_odrs_provider_upvote_review		(GsOdrsProvider		 *self,
+							 GsApp			 *app,
+							 AsReview		 *review,
+							 GCancellable		 *cancellable,
+							 GError			**error);
+gboolean	 gs_odrs_provider_downvote_review	(GsOdrsProvider		 *self,
+							 GsApp			 *app,
+							 AsReview		 *review,
+							 GCancellable		 *cancellable,
+							 GError			**error);
+gboolean	 gs_odrs_provider_dismiss_review	(GsOdrsProvider		 *self,
+							 GsApp			 *app,
+							 AsReview		 *review,
+							 GCancellable		 *cancellable,
+							 GError			**error);
+gboolean	 gs_odrs_provider_remove_review		(GsOdrsProvider		 *self,
+							 GsApp			 *app,
+							 AsReview		 *review,
+							 GCancellable		 *cancellable,
+							 GError			**error);
+
+gboolean	 gs_odrs_provider_add_unvoted_reviews	(GsOdrsProvider		 *self,
+							 GsAppList		 *list,
+							 GCancellable		 *cancellable,
+							 GError			**error);
+
+G_END_DECLS
diff --git a/lib/gs-os-release.c b/lib/gs-os-release.c
new file mode 100644
index 0000000..191a385
--- /dev/null
+++ b/lib/gs-os-release.c
@@ -0,0 +1,347 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2016 Kalev Lember <klember@redhat.com>
+ * Copyright (C) 2016 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: LGPL-2.1+
+ */
+
+/**
+ * SECTION:gs-os-release
+ * @title: GsOsRelease
+ * @include: gnome-software.h
+ * @stability: Unstable
+ * @short_description: Data from os-release
+ *
+ * This object allows plugins to parse /etc/os-release for distribution
+ * metadata information.
+ */
+
+#include "config.h"
+
+#include <glib.h>
+
+#include "gs-os-release.h"
+
+struct _GsOsRelease
+{
+	GObject			 parent_instance;
+	gchar			*name;
+	gchar			*version;
+	gchar			*id;
+	gchar			**id_like;
+	gchar			*version_id;
+	gchar			*pretty_name;
+	gchar			*cpe_name;
+	gchar			*distro_codename;
+	gchar			*home_url;
+};
+
+static void gs_os_release_initable_iface_init (GInitableIface *iface);
+
+G_DEFINE_TYPE_WITH_CODE (GsOsRelease, gs_os_release, G_TYPE_OBJECT,
+			 G_IMPLEMENT_INTERFACE(G_TYPE_INITABLE, gs_os_release_initable_iface_init))
+
+static gboolean
+gs_os_release_initable_init (GInitable *initable,
+			     GCancellable *cancellable,
+			     GError **error)
+{
+	GsOsRelease *os_release = GS_OS_RELEASE (initable);
+	const gchar *filename;
+	g_autofree gchar *data = NULL;
+	g_auto(GStrv) lines = NULL;
+	guint i;
+
+	g_return_val_if_fail (GS_IS_OS_RELEASE (os_release), FALSE);
+	g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
+
+	/* get contents */
+	filename = g_getenv ("GS_SELF_TEST_OS_RELEASE_FILENAME");
+	if (filename == NULL) {
+		filename = "/etc/os-release";
+		if (!g_file_test (filename, G_FILE_TEST_EXISTS))
+			filename = "/usr/lib/os-release";
+	}
+	if (!g_file_get_contents (filename, &data, NULL, error))
+		return FALSE;
+
+	/* parse */
+	lines = g_strsplit (data, "\n", -1);
+	for (i = 0; lines[i] != NULL; i++) {
+		gchar *tmp;
+
+		/* split the line up into two halves */
+		tmp = g_strstr_len (lines[i], -1, "=");
+		if (tmp == NULL)
+			continue;
+		*tmp = '\0';
+		tmp++;
+
+		/* ignore trailing quote */
+		if (tmp[0] == '\"')
+			tmp++;
+
+		/* ignore trailing quote */
+		g_strdelimit (tmp, "\"", '\0');
+
+		/* match fields we're interested in */
+		if (g_strcmp0 (lines[i], "NAME") == 0) {
+			os_release->name = g_strdup (tmp);
+			continue;
+		}
+		if (g_strcmp0 (lines[i], "VERSION") == 0) {
+			os_release->version = g_strdup (tmp);
+			continue;
+		}
+		if (g_strcmp0 (lines[i], "ID") == 0) {
+			os_release->id = g_strdup (tmp);
+			continue;
+		}
+		if (g_strcmp0 (lines[i], "ID_LIKE") == 0) {
+			os_release->id_like = g_strsplit (tmp, " ", 0);
+			continue;
+		}
+		if (g_strcmp0 (lines[i], "VERSION_ID") == 0) {
+			os_release->version_id = g_strdup (tmp);
+			continue;
+		}
+		if (g_strcmp0 (lines[i], "PRETTY_NAME") == 0) {
+			os_release->pretty_name = g_strdup (tmp);
+			continue;
+		}
+		if (g_strcmp0 (lines[i], "CPE_NAME") == 0) {
+			os_release->cpe_name = g_strdup (tmp);
+			continue;
+		}
+		if (g_strcmp0 (lines[i], "UBUNTU_CODENAME") == 0) {
+			os_release->distro_codename = g_strdup (tmp);
+			continue;
+		}
+		if (g_strcmp0 (lines[i], "HOME_URL") == 0) {
+			os_release->home_url = g_strdup (tmp);
+			continue;
+		}
+	}
+	return TRUE;
+}
+
+/**
+ * gs_os_release_get_name:
+ * @os_release: A #GsOsRelease
+ *
+ * Gets the name from the os-release parser.
+ *
+ * Returns: a string, or %NULL
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_os_release_get_name (GsOsRelease *os_release)
+{
+	g_return_val_if_fail (GS_IS_OS_RELEASE (os_release), NULL);
+	return os_release->name;
+}
+
+/**
+ * gs_os_release_get_version:
+ * @os_release: A #GsOsRelease
+ *
+ * Gets the version from the os-release parser.
+ *
+ * Returns: a string, or %NULL
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_os_release_get_version (GsOsRelease *os_release)
+{
+	g_return_val_if_fail (GS_IS_OS_RELEASE (os_release), NULL);
+	return os_release->version;
+}
+
+/**
+ * gs_os_release_get_id:
+ * @os_release: A #GsOsRelease
+ *
+ * Gets the ID from the os-release parser.
+ *
+ * Returns: a string, or %NULL
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_os_release_get_id (GsOsRelease *os_release)
+{
+	g_return_val_if_fail (GS_IS_OS_RELEASE (os_release), NULL);
+	return os_release->id;
+}
+
+/**
+ * gs_os_release_get_id_like:
+ * @os_release: A #GsOsRelease
+ *
+ * Gets the ID_LIKE from the os-release parser. This is a list of operating
+ * systems that are "closely related" to the local operating system, possibly
+ * by being a derivative distribution.
+ *
+ * Returns: a %NULL terminated list
+ *
+ * Since: 3.26.2
+ **/
+const gchar * const *
+gs_os_release_get_id_like (GsOsRelease *os_release)
+{
+	g_return_val_if_fail (GS_IS_OS_RELEASE (os_release), NULL);
+	return (const gchar * const *) os_release->id_like;
+}
+
+/**
+ * gs_os_release_get_version_id:
+ * @os_release: A #GsOsRelease
+ *
+ * Gets the version ID from the os-release parser.
+ *
+ * Returns: a string, or %NULL
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_os_release_get_version_id (GsOsRelease *os_release)
+{
+	g_return_val_if_fail (GS_IS_OS_RELEASE (os_release), NULL);
+	return os_release->version_id;
+}
+
+/**
+ * gs_os_release_get_pretty_name:
+ * @os_release: A #GsOsRelease
+ *
+ * Gets the pretty name from the os-release parser.
+ *
+ * Returns: a string, or %NULL
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_os_release_get_pretty_name (GsOsRelease *os_release)
+{
+	g_return_val_if_fail (GS_IS_OS_RELEASE (os_release), NULL);
+	return os_release->pretty_name;
+}
+
+/**
+ * gs_os_release_get_cpe_name:
+ * @os_release: A #GsOsRelease
+ *
+ * Gets the pretty name from the os-release parser.
+ *
+ * Returns: a string, or %NULL
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_os_release_get_cpe_name (GsOsRelease *os_release)
+{
+	g_return_val_if_fail (GS_IS_OS_RELEASE (os_release), NULL);
+	return os_release->cpe_name;
+}
+
+/**
+ * gs_os_release_get_distro_codename:
+ * @os_release: A #GsOsRelease
+ *
+ * Gets the distro codename from the os-release parser.
+ *
+ * Returns: a string, or %NULL
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_os_release_get_distro_codename (GsOsRelease *os_release)
+{
+	g_return_val_if_fail (GS_IS_OS_RELEASE (os_release), NULL);
+	return os_release->distro_codename;
+}
+
+/**
+ * gs_os_release_get_home_url:
+ * @os_release: A #GsOsRelease
+ *
+ * Gets the home URL from the os-release parser.
+ *
+ * Returns: a string, or %NULL
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_os_release_get_home_url (GsOsRelease *os_release)
+{
+	g_return_val_if_fail (GS_IS_OS_RELEASE (os_release), NULL);
+	return os_release->home_url;
+}
+
+static void
+gs_os_release_finalize (GObject *object)
+{
+	GsOsRelease *os_release = GS_OS_RELEASE (object);
+	g_free (os_release->name);
+	g_free (os_release->version);
+	g_free (os_release->id);
+	g_strfreev (os_release->id_like);
+	g_free (os_release->version_id);
+	g_free (os_release->pretty_name);
+	g_free (os_release->cpe_name);
+	g_free (os_release->distro_codename);
+	g_free (os_release->home_url);
+	G_OBJECT_CLASS (gs_os_release_parent_class)->finalize (object);
+}
+
+static void
+gs_os_release_class_init (GsOsReleaseClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+	object_class->finalize = gs_os_release_finalize;
+}
+
+static void
+gs_os_release_initable_iface_init (GInitableIface *iface)
+{
+	iface->init = gs_os_release_initable_init;
+}
+
+static void
+gs_os_release_init (GsOsRelease *os_release)
+{
+}
+
+/**
+ * gs_os_release_new:
+ * @error: a #GError, or %NULL
+ *
+ * Returns a new reference to a #GsOsRelease. The information may be cached.
+ *
+ * Returns: (transfer full): A new reference to a #GsOsRelease, or %NULL for error
+ *
+ * Since: 3.22
+ **/
+GsOsRelease *
+gs_os_release_new (GError **error)
+{
+	static gsize initialised = 0;
+	static GsOsRelease *os_release = NULL;
+	static GError *os_release_error = NULL;
+
+	if (g_once_init_enter (&initialised)) {
+		os_release = g_initable_new (GS_TYPE_OS_RELEASE, NULL, &os_release_error, NULL);
+		g_once_init_leave (&initialised, 1);
+	}
+
+	if (os_release != NULL) {
+		return g_object_ref (os_release);
+	} else {
+		g_propagate_error (error, g_error_copy (os_release_error));
+		return NULL;
+	}
+}
diff --git a/lib/gs-os-release.h b/lib/gs-os-release.h
new file mode 100644
index 0000000..336f17c
--- /dev/null
+++ b/lib/gs-os-release.h
@@ -0,0 +1,33 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2016 Kalev Lember <klember@redhat.com>
+ * Copyright (C) 2016 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: LGPL-2.1+
+ */
+
+#pragma once
+
+#include <glib-object.h>
+
+#include "gs-app.h"
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_OS_RELEASE (gs_os_release_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsOsRelease, gs_os_release, GS, OS_RELEASE, GObject)
+
+GsOsRelease		*gs_os_release_new			(GError		**error);
+const gchar		*gs_os_release_get_name			(GsOsRelease	*os_release);
+const gchar		*gs_os_release_get_version		(GsOsRelease	*os_release);
+const gchar		*gs_os_release_get_id			(GsOsRelease	*os_release);
+const gchar *	  const *gs_os_release_get_id_like		(GsOsRelease	*os_release);
+const gchar		*gs_os_release_get_version_id		(GsOsRelease	*os_release);
+const gchar		*gs_os_release_get_pretty_name		(GsOsRelease	*os_release);
+const gchar		*gs_os_release_get_cpe_name		(GsOsRelease	*os_release);
+const gchar		*gs_os_release_get_distro_codename	(GsOsRelease	*os_release);
+const gchar		*gs_os_release_get_home_url		(GsOsRelease	*os_release);
+
+G_END_DECLS
diff --git a/lib/gs-plugin-event.c b/lib/gs-plugin-event.c
new file mode 100644
index 0000000..699e529
--- /dev/null
+++ b/lib/gs-plugin-event.c
@@ -0,0 +1,453 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2016 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2016 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-plugin-event
+ * @title: GsPluginEvent
+ * @include: gnome-software.h
+ * @stability: Unstable
+ * @short_description: Information about a plugin event
+ *
+ * These functions provide a way for plugins to tell the UI layer about events
+ * that may require displaying to the user. Plugins should not assume that a
+ * specific event is actually shown to the user as it may be ignored
+ * automatically.
+ */
+
+#include "config.h"
+
+#include <glib.h>
+
+#include "gs-enums.h"
+#include "gs-plugin-private.h"
+#include "gs-plugin-event.h"
+#include "gs-plugin-job.h"
+#include "gs-utils.h"
+
+struct _GsPluginEvent
+{
+	GObject			 parent_instance;
+	GsApp			*app;
+	GsApp			*origin;
+	GsPluginAction		 action;
+	GsPluginJob		*job;  /* (owned) (nullable) */
+	GError			*error;
+	GsPluginEventFlag	 flags;
+	gchar			*unique_id;
+};
+
+G_DEFINE_TYPE (GsPluginEvent, gs_plugin_event, G_TYPE_OBJECT)
+
+typedef enum {
+	PROP_APP = 1,
+	PROP_ORIGIN,
+	PROP_ACTION,
+	PROP_JOB,
+	PROP_ERROR,
+} GsPluginEventProperty;
+
+static GParamSpec *props[PROP_ERROR + 1] = { NULL, };
+
+/**
+ * gs_plugin_event_get_app:
+ * @event: A #GsPluginEvent
+ *
+ * Gets an application that created the event.
+ *
+ * Returns: (transfer none): a #GsApp, or %NULL if unset
+ *
+ * Since: 3.22
+ **/
+GsApp *
+gs_plugin_event_get_app (GsPluginEvent *event)
+{
+	g_return_val_if_fail (GS_IS_PLUGIN_EVENT (event), NULL);
+	return event->app;
+}
+
+/**
+ * gs_plugin_event_get_origin:
+ * @event: A #GsPluginEvent
+ *
+ * Gets an origin that created the event.
+ *
+ * Returns: (transfer none): a #GsApp, or %NULL if unset
+ *
+ * Since: 3.22
+ **/
+GsApp *
+gs_plugin_event_get_origin (GsPluginEvent *event)
+{
+	g_return_val_if_fail (GS_IS_PLUGIN_EVENT (event), NULL);
+	return event->origin;
+}
+
+/**
+ * gs_plugin_event_get_action:
+ * @event: A #GsPluginEvent
+ *
+ * Gets an action that created the event.
+ *
+ * Returns: (transfer none): a #GsPluginAction, e.g. %GS_PLUGIN_ACTION_UPDATE
+ *
+ * Since: 3.22
+ **/
+GsPluginAction
+gs_plugin_event_get_action (GsPluginEvent *event)
+{
+	g_return_val_if_fail (GS_IS_PLUGIN_EVENT (event), 0);
+	return event->action;
+}
+
+/**
+ * gs_plugin_event_get_job:
+ * @event: A #GsPluginEvent
+ *
+ * Gets the job that created the event.
+ *
+ * Returns: (transfer none) (nullable): a #GsPluginJob
+ *
+ * Since: 42
+ **/
+GsPluginJob *
+gs_plugin_event_get_job (GsPluginEvent *event)
+{
+	g_return_val_if_fail (GS_IS_PLUGIN_EVENT (event), NULL);
+	return event->job;
+}
+
+/**
+ * gs_plugin_event_get_unique_id:
+ * @event: A #GsPluginEvent
+ *
+ * Gets the unique ID for the event. In most cases (if an app has been set)
+ * this will just be the actual #GsApp unique-id. In the cases where only error
+ * has been set a virtual (but plausible) ID will be generated.
+ *
+ * Returns: a string, or %NULL for invalid
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_plugin_event_get_unique_id (GsPluginEvent *event)
+{
+	/* just proxy */
+	if (event->origin != NULL &&
+	    gs_app_get_unique_id (event->origin) != NULL) {
+		return gs_app_get_unique_id (event->origin);
+	}
+	if (event->app != NULL &&
+	    gs_app_get_unique_id (event->app) != NULL) {
+		return gs_app_get_unique_id (event->app);
+	}
+
+	/* generate from error */
+	if (event->error != NULL) {
+		if (event->unique_id == NULL) {
+			g_autofree gchar *id = NULL;
+			id = g_strdup_printf ("%s.error",
+					      gs_plugin_error_to_string (event->error->code));
+			event->unique_id = gs_utils_build_unique_id (AS_COMPONENT_SCOPE_UNKNOWN,
+								     AS_BUNDLE_KIND_UNKNOWN,
+								     NULL,
+								     id,
+								     NULL);
+		}
+		return event->unique_id;
+	}
+
+	/* failed */
+	return NULL;
+}
+
+/**
+ * gs_plugin_event_get_kind:
+ * @event: A #GsPluginEvent
+ * @flag: A #GsPluginEventFlag, e.g. %GS_PLUGIN_EVENT_FLAG_INVALID
+ *
+ * Adds a flag to the event.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_event_add_flag (GsPluginEvent *event, GsPluginEventFlag flag)
+{
+	g_return_if_fail (GS_IS_PLUGIN_EVENT (event));
+	event->flags |= flag;
+}
+
+/**
+ * gs_plugin_event_set_kind:
+ * @event: A #GsPluginEvent
+ * @flag: A #GsPluginEventFlag, e.g. %GS_PLUGIN_EVENT_FLAG_INVALID
+ *
+ * Removes a flag from the event.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_event_remove_flag (GsPluginEvent *event, GsPluginEventFlag flag)
+{
+	g_return_if_fail (GS_IS_PLUGIN_EVENT (event));
+	event->flags &= ~flag;
+}
+
+/**
+ * gs_plugin_event_has_flag:
+ * @event: A #GsPluginEvent
+ * @flag: A #GsPluginEventFlag, e.g. %GS_PLUGIN_EVENT_FLAG_INVALID
+ *
+ * Finds out if the event has a specific flag.
+ *
+ * Returns: %TRUE if the flag is set
+ *
+ * Since: 3.22
+ **/
+gboolean
+gs_plugin_event_has_flag (GsPluginEvent *event, GsPluginEventFlag flag)
+{
+	g_return_val_if_fail (GS_IS_PLUGIN_EVENT (event), FALSE);
+	return ((event->flags & flag) > 0);
+}
+
+/**
+ * gs_plugin_event_get_error:
+ * @event: A #GsPluginEvent
+ *
+ * Gets the event error.
+ *
+ * Returns: a #GError, or %NULL for unset
+ *
+ * Since: 3.22
+ **/
+const GError *
+gs_plugin_event_get_error (GsPluginEvent *event)
+{
+	return event->error;
+}
+
+static void
+gs_plugin_event_get_property (GObject    *object,
+                              guint       prop_id,
+                              GValue     *value,
+                              GParamSpec *pspec)
+{
+	GsPluginEvent *self = GS_PLUGIN_EVENT (object);
+
+	switch ((GsPluginEventProperty) prop_id) {
+	case PROP_APP:
+		g_value_set_object (value, self->app);
+		break;
+	case PROP_ORIGIN:
+		g_value_set_object (value, self->origin);
+		break;
+	case PROP_ACTION:
+		g_value_set_enum (value, self->action);
+		break;
+	case PROP_JOB:
+		g_value_set_object (value, self->job);
+		break;
+	case PROP_ERROR:
+		g_value_set_boxed (value, self->error);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_plugin_event_set_property (GObject      *object,
+                              guint         prop_id,
+                              const GValue *value,
+                              GParamSpec   *pspec)
+{
+	GsPluginEvent *self = GS_PLUGIN_EVENT (object);
+
+	switch ((GsPluginEventProperty) prop_id) {
+	case PROP_APP:
+		/* Construct only. */
+		g_assert (self->app == NULL);
+		self->app = g_value_dup_object (value);
+		g_object_notify_by_pspec (object, props[prop_id]);
+		break;
+	case PROP_ORIGIN:
+		/* Construct only. */
+		g_assert (self->origin == NULL);
+		self->origin = g_value_dup_object (value);
+		g_object_notify_by_pspec (object, props[prop_id]);
+		break;
+	case PROP_ACTION:
+		/* Construct only. */
+		g_assert (self->action == GS_PLUGIN_ACTION_UNKNOWN);
+		self->action = g_value_get_enum (value);
+		g_object_notify_by_pspec (object, props[prop_id]);
+		break;
+	case PROP_JOB:
+		/* Construct only. */
+		g_assert (self->job == NULL);
+		self->job = g_value_dup_object (value);
+		g_object_notify_by_pspec (object, props[prop_id]);
+		break;
+	case PROP_ERROR:
+		/* Construct only. */
+		g_assert (self->error == NULL);
+		self->error = g_value_dup_boxed (value);
+		if (self->error) {
+			/* Just in case the caller left there any D-Bus remote error notes */
+			g_dbus_error_strip_remote_error (self->error);
+		}
+		g_object_notify_by_pspec (object, props[prop_id]);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_plugin_event_dispose (GObject *object)
+{
+	GsPluginEvent *event = GS_PLUGIN_EVENT (object);
+
+	g_clear_object (&event->app);
+	g_clear_object (&event->origin);
+	g_clear_object (&event->job);
+
+	G_OBJECT_CLASS (gs_plugin_event_parent_class)->dispose (object);
+}
+
+static void
+gs_plugin_event_finalize (GObject *object)
+{
+	GsPluginEvent *event = GS_PLUGIN_EVENT (object);
+
+	g_clear_error (&event->error);
+	g_free (event->unique_id);
+
+	G_OBJECT_CLASS (gs_plugin_event_parent_class)->finalize (object);
+}
+
+static void
+gs_plugin_event_class_init (GsPluginEventClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+	object_class->get_property = gs_plugin_event_get_property;
+	object_class->set_property = gs_plugin_event_set_property;
+	object_class->dispose = gs_plugin_event_dispose;
+	object_class->finalize = gs_plugin_event_finalize;
+
+	/**
+	 * GsPluginEvent:app: (nullable)
+	 *
+	 * The application (or source, or whatever component) that caused the
+	 * event to be created.
+	 *
+	 * Since: 42
+	 */
+	props[PROP_APP] =
+		g_param_spec_object ("app", "App",
+				     "The application (or source, or whatever component) that caused the event to be created.",
+				     GS_TYPE_APP,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				     G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPluginEvent:origin: (nullable)
+	 *
+	 * The origin that caused the event to be created.
+	 *
+	 * Since: 42
+	 */
+	props[PROP_ORIGIN] =
+		g_param_spec_object ("origin", "Origin",
+				     "The origin that caused the event to be created.",
+				     GS_TYPE_APP,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				     G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPluginEvent:action:
+	 *
+	 * The action that caused the event to be created.
+	 *
+	 * Since: 42
+	 */
+	props[PROP_ACTION] =
+		g_param_spec_enum ("action", "Action",
+				   "The action that caused the event to be created.",
+				   GS_TYPE_PLUGIN_ACTION, GS_PLUGIN_ACTION_UNKNOWN,
+				   G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				   G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPluginEvent:job: (nullable)
+	 *
+	 * The job that caused the event to be created.
+	 *
+	 * Since: 42
+	 */
+	props[PROP_JOB] =
+		g_param_spec_object ("job", "Job",
+				     "The job that caused the event to be created.",
+				     GS_TYPE_PLUGIN_JOB,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				     G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPluginEvent:error: (nullable)
+	 *
+	 * The error the event is reporting.
+	 *
+	 * Since: 42
+	 */
+	props[PROP_ERROR] =
+		g_param_spec_boxed ("error", "Error",
+				    "The error the event is reporting.",
+				    G_TYPE_ERROR,
+				    G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				    G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	g_object_class_install_properties (object_class, G_N_ELEMENTS (props), props);
+}
+
+static void
+gs_plugin_event_init (GsPluginEvent *event)
+{
+}
+
+/**
+ * gs_plugin_event_new:
+ * @first_property_name: the name of the first property
+ * @...: the value of the first property, followed by zero or more pairs of
+ *   property name/value pairs, then %NULL
+ *
+ * Creates a new event.
+ *
+ * The arguments are as for g_object_new(): property name/value pairs to set
+ * the properties of the event.
+ *
+ * Returns: (transfer full): A newly allocated #GsPluginEvent
+ *
+ * Since: 42
+ **/
+GsPluginEvent *
+gs_plugin_event_new (const gchar *first_property_name,
+		     ...)
+{
+	GsPluginEvent *event;
+	va_list args;
+
+	va_start (args, first_property_name);
+	event = GS_PLUGIN_EVENT (g_object_new_valist (GS_TYPE_PLUGIN_EVENT, first_property_name, args));
+	va_end (args);
+
+	return GS_PLUGIN_EVENT (event);
+}
diff --git a/lib/gs-plugin-event.h b/lib/gs-plugin-event.h
new file mode 100644
index 0000000..949eb85
--- /dev/null
+++ b/lib/gs-plugin-event.h
@@ -0,0 +1,61 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2016 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib-object.h>
+
+#include "gs-app.h"
+#include "gs-plugin-types.h"
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_PLUGIN_EVENT (gs_plugin_event_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsPluginEvent, gs_plugin_event, GS, PLUGIN_EVENT, GObject)
+
+typedef struct _GsPluginJob GsPluginJob;
+
+/**
+ * GsPluginEventFlag:
+ * @GS_PLUGIN_EVENT_FLAG_NONE:		No special flags set
+ * @GS_PLUGIN_EVENT_FLAG_INVALID:	Event is no longer valid, e.g. was dismissed
+ * @GS_PLUGIN_EVENT_FLAG_VISIBLE:	Event is is visible on the screen
+ * @GS_PLUGIN_EVENT_FLAG_WARNING:	Event should be shown with more urgency
+ * @GS_PLUGIN_EVENT_FLAG_INTERACTIVE:	The plugin job was created with interactive=True
+ *
+ * Any flags an event can have.
+ **/
+typedef enum {
+	GS_PLUGIN_EVENT_FLAG_NONE		= 0,		/* Since: 3.22 */
+	GS_PLUGIN_EVENT_FLAG_INVALID		= 1 << 0,	/* Since: 3.22 */
+	GS_PLUGIN_EVENT_FLAG_VISIBLE		= 1 << 1,	/* Since: 3.22 */
+	GS_PLUGIN_EVENT_FLAG_WARNING		= 1 << 2,	/* Since: 3.22 */
+	GS_PLUGIN_EVENT_FLAG_INTERACTIVE	= 1 << 3,	/* Since: 3.30 */
+	GS_PLUGIN_EVENT_FLAG_LAST  /*< skip >*/
+} GsPluginEventFlag;
+
+GsPluginEvent		*gs_plugin_event_new		(const gchar		*first_property_name,
+							 ...) G_GNUC_NULL_TERMINATED;
+
+const gchar		*gs_plugin_event_get_unique_id	(GsPluginEvent		*event);
+
+GsApp			*gs_plugin_event_get_app	(GsPluginEvent		*event);
+GsApp			*gs_plugin_event_get_origin	(GsPluginEvent		*event);
+GsPluginAction		 gs_plugin_event_get_action	(GsPluginEvent		*event);
+GsPluginJob		*gs_plugin_event_get_job	(GsPluginEvent		*event);
+const GError		*gs_plugin_event_get_error	(GsPluginEvent		*event);
+
+void			 gs_plugin_event_add_flag	(GsPluginEvent		*event,
+							 GsPluginEventFlag	 flag);
+void			 gs_plugin_event_remove_flag	(GsPluginEvent		*event,
+							 GsPluginEventFlag	 flag);
+gboolean		 gs_plugin_event_has_flag	(GsPluginEvent		*event,
+							 GsPluginEventFlag	 flag);
+
+G_END_DECLS
diff --git a/lib/gs-plugin-helpers.c b/lib/gs-plugin-helpers.c
new file mode 100644
index 0000000..40c8a61
--- /dev/null
+++ b/lib/gs-plugin-helpers.c
@@ -0,0 +1,338 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-plugin-helpers
+ * @short_description: Helpers for storing call closures for #GsPlugin vfuncs
+ *
+ * The helpers in this file each create a context structure to store the
+ * arguments passed to a standard #GsPlugin vfunc.
+ *
+ * These are intended to be used by plugin implementations to easily create
+ * #GTasks for handling #GsPlugin vfunc calls, without all having to write the
+ * same code to create a structure to wrap the vfunc arguments.
+ *
+ * Since: 42
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <glib-object.h>
+
+#include "gs-plugin-helpers.h"
+
+/**
+ * gs_plugin_refine_data_new:
+ * @list: list of #GsApps to refine
+ * @flags: refine flags
+ *
+ * Context data for a call to #GsPluginClass.refine_async.
+ *
+ * Returns: (transfer full): context data structure
+ * Since: 42
+ */
+GsPluginRefineData *
+gs_plugin_refine_data_new (GsAppList           *list,
+                           GsPluginRefineFlags  flags)
+{
+	g_autoptr(GsPluginRefineData) data = g_new0 (GsPluginRefineData, 1);
+	data->list = g_object_ref (list);
+	data->flags = flags;
+
+	return g_steal_pointer (&data);
+}
+
+/**
+ * gs_plugin_refine_data_new_task:
+ * @source_object: task source object
+ * @list: list of #GsApps to refine
+ * @flags: refine flags
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @callback: function to call once asynchronous operation is finished
+ * @user_data: data to pass to @callback
+ *
+ * Create a #GTask for a refine operation with the given arguments. The task
+ * data will be set to a #GsPluginRefineData containing the given context.
+ *
+ * This is essentially a combination of gs_plugin_refine_data_new(),
+ * g_task_new() and g_task_set_task_data().
+ *
+ * Returns: (transfer full): new #GTask with the given context data
+ * Since: 42
+ */
+GTask *
+gs_plugin_refine_data_new_task (gpointer             source_object,
+                                GsAppList           *list,
+                                GsPluginRefineFlags  flags,
+                                GCancellable        *cancellable,
+                                GAsyncReadyCallback  callback,
+                                gpointer             user_data)
+{
+	g_autoptr(GTask) task = g_task_new (source_object, cancellable, callback, user_data);
+	g_task_set_task_data (task, gs_plugin_refine_data_new (list, flags), (GDestroyNotify) gs_plugin_refine_data_free);
+	return g_steal_pointer (&task);
+}
+
+/**
+ * gs_plugin_refine_data_free:
+ * @data: (transfer full): a #GsPluginRefineData
+ *
+ * Free the given @data.
+ *
+ * Since: 42
+ */
+void
+gs_plugin_refine_data_free (GsPluginRefineData *data)
+{
+	g_clear_object (&data->list);
+	g_free (data);
+}
+
+/**
+ * gs_plugin_refresh_metadata_data_new:
+ * @cache_age_secs: maximum allowed age of the cache in order for it to remain valid, in seconds
+ * @flags: refresh metadata flags
+ *
+ * Context data for a call to #GsPluginClass.refresh_metadata_async.
+ *
+ * Returns: (transfer full): context data structure
+ * Since: 42
+ */
+GsPluginRefreshMetadataData *
+gs_plugin_refresh_metadata_data_new (guint64                      cache_age_secs,
+                                     GsPluginRefreshMetadataFlags flags)
+{
+	g_autoptr(GsPluginRefreshMetadataData) data = g_new0 (GsPluginRefreshMetadataData, 1);
+	data->cache_age_secs = cache_age_secs;
+	data->flags = flags;
+
+	return g_steal_pointer (&data);
+}
+
+/**
+ * gs_plugin_refresh_metadata_data_free:
+ * @data: (transfer full): a #GsPluginRefreshMetadataData
+ *
+ * Free the given @data.
+ *
+ * Since: 42
+ */
+void
+gs_plugin_refresh_metadata_data_free (GsPluginRefreshMetadataData *data)
+{
+	g_free (data);
+}
+
+/**
+ * gs_plugin_list_apps_data_new:
+ * @query: (nullable) (transfer none): a query to filter apps, or %NULL for
+ *   no filtering
+ * @flags: list apps flags
+ *
+ * Context data for a call to #GsPluginClass.list_apps_async.
+ *
+ * Returns: (transfer full): context data structure
+ * Since: 43
+ */
+GsPluginListAppsData *
+gs_plugin_list_apps_data_new (GsAppQuery            *query,
+                              GsPluginListAppsFlags  flags)
+{
+	g_autoptr(GsPluginListAppsData) data = g_new0 (GsPluginListAppsData, 1);
+	data->query = (query != NULL) ? g_object_ref (query) : NULL;
+	data->flags = flags;
+
+	return g_steal_pointer (&data);
+}
+
+/**
+ * gs_plugin_list_apps_data_new_task:
+ * @source_object: task source object
+ * @query: (nullable) (transfer none): a query to filter apps, or %NULL for
+ *   no filtering
+ * @flags: list apps flags
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @callback: function to call once asynchronous operation is finished
+ * @user_data: data to pass to @callback
+ *
+ * Create a #GTask for a list apps operation with the given arguments. The task
+ * data will be set to a #GsPluginListAppsData containing the given context.
+ *
+ * This is essentially a combination of gs_plugin_list_apps_data_new(),
+ * g_task_new() and g_task_set_task_data().
+ *
+ * Returns: (transfer full): new #GTask with the given context data
+ * Since: 43
+ */
+GTask *
+gs_plugin_list_apps_data_new_task (gpointer               source_object,
+                                   GsAppQuery            *query,
+                                   GsPluginListAppsFlags  flags,
+                                   GCancellable          *cancellable,
+                                   GAsyncReadyCallback    callback,
+                                   gpointer               user_data)
+{
+	g_autoptr(GTask) task = g_task_new (source_object, cancellable, callback, user_data);
+	g_task_set_task_data (task, gs_plugin_list_apps_data_new (query, flags), (GDestroyNotify) gs_plugin_list_apps_data_free);
+	return g_steal_pointer (&task);
+}
+
+/**
+ * gs_plugin_list_apps_data_free:
+ * @data: (transfer full): a #GsPluginListAppsData
+ *
+ * Free the given @data.
+ *
+ * Since: 43
+ */
+void
+gs_plugin_list_apps_data_free (GsPluginListAppsData *data)
+{
+	g_clear_object (&data->query);
+	g_free (data);
+}
+
+/**
+ * gs_plugin_manage_repository_data_new:
+ * @repository: (not-nullable) (transfer none): a repository to manage
+ * @flags: manage repository flags
+ *
+ * Common context data for a call to #GsPluginClass.install_repository_async,
+ * #GsPluginClass.remove_repository_async, #GsPluginClass.enable_repository_async
+ * and #GsPluginClass.disable_repository_async.
+ *
+ * Returns: (transfer full): context data structure
+ * Since: 43
+ */
+GsPluginManageRepositoryData *
+gs_plugin_manage_repository_data_new (GsApp			   *repository,
+				      GsPluginManageRepositoryFlags flags)
+{
+	g_autoptr(GsPluginManageRepositoryData) data = g_new0 (GsPluginManageRepositoryData, 1);
+	data->repository = g_object_ref (repository);
+	data->flags = flags;
+
+	return g_steal_pointer (&data);
+}
+
+/**
+ * gs_plugin_manage_repository_data_new_task:
+ * @source_object: task source object
+ * @repository: (not-nullable) (transfer none): a repository to manage
+ * @flags: manage repository flags
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @callback: function to call once asynchronous operation is finished
+ * @user_data: data to pass to @callback
+ *
+ * Create a #GTask for a manage repository operation with the given arguments. The task
+ * data will be set to a #GsPluginManageRepositoryData containing the given context.
+ *
+ * This is essentially a combination of gs_plugin_manage_repository_data_new(),
+ * g_task_new() and g_task_set_task_data().
+ *
+ * Returns: (transfer full): new #GTask with the given context data
+ * Since: 43
+ */
+GTask *
+gs_plugin_manage_repository_data_new_task (gpointer			 source_object,
+					   GsApp			*repository,
+					   GsPluginManageRepositoryFlags flags,
+					   GCancellable			*cancellable,
+					   GAsyncReadyCallback		 callback,
+					   gpointer			 user_data)
+{
+	g_autoptr(GTask) task = g_task_new (source_object, cancellable, callback, user_data);
+	g_task_set_task_data (task, gs_plugin_manage_repository_data_new (repository, flags), (GDestroyNotify) gs_plugin_manage_repository_data_free);
+	return g_steal_pointer (&task);
+}
+
+/**
+ * gs_plugin_manage_repository_data_free:
+ * @data: (transfer full): a #GsPluginManageRepositoryData
+ *
+ * Free the given @data.
+ *
+ * Since: 43
+ */
+void
+gs_plugin_manage_repository_data_free (GsPluginManageRepositoryData *data)
+{
+	g_clear_object (&data->repository);
+	g_free (data);
+}
+
+/**
+ * gs_plugin_refine_categories_data_new:
+ * @list: (element-type GsCategory): list of #GsCategory objects to refine
+ * @flags: refine flags
+ *
+ * Context data for a call to #GsPluginClass.refine_categories_async.
+ *
+ * Returns: (transfer full): context data structure
+ * Since: 43
+ */
+GsPluginRefineCategoriesData *
+gs_plugin_refine_categories_data_new (GPtrArray                     *list,
+                                      GsPluginRefineCategoriesFlags  flags)
+{
+	g_autoptr(GsPluginRefineCategoriesData) data = g_new0 (GsPluginRefineCategoriesData, 1);
+	data->list = g_ptr_array_ref (list);
+	data->flags = flags;
+
+	return g_steal_pointer (&data);
+}
+
+/**
+ * gs_plugin_refine_categories_data_new_task:
+ * @source_object: task source object
+ * @list: (element-type GsCategory): list of #GsCategory objects to refine
+ * @flags: refine flags
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @callback: function to call once asynchronous operation is finished
+ * @user_data: data to pass to @callback
+ *
+ * Create a #GTask for a refine categories operation with the given arguments.
+ * The task data will be set to a #GsPluginRefineCategoriesData containing the
+ * given context.
+ *
+ * This is essentially a combination of gs_plugin_refine_categories_data_new(),
+ * g_task_new() and g_task_set_task_data().
+ *
+ * Returns: (transfer full): new #GTask with the given context data
+ * Since: 43
+ */
+GTask *
+gs_plugin_refine_categories_data_new_task (gpointer                       source_object,
+                                           GPtrArray                     *list,
+                                           GsPluginRefineCategoriesFlags  flags,
+                                           GCancellable                  *cancellable,
+                                           GAsyncReadyCallback            callback,
+                                           gpointer                       user_data)
+{
+	g_autoptr(GTask) task = g_task_new (source_object, cancellable, callback, user_data);
+	g_task_set_task_data (task, gs_plugin_refine_categories_data_new (list, flags), (GDestroyNotify) gs_plugin_refine_categories_data_free);
+	return g_steal_pointer (&task);
+}
+
+/**
+ * gs_plugin_refine_categories_data_free:
+ * @data: (transfer full): a #GsPluginRefineCategoriesData
+ *
+ * Free the given @data.
+ *
+ * Since: 43
+ */
+void
+gs_plugin_refine_categories_data_free (GsPluginRefineCategoriesData *data)
+{
+	g_clear_pointer (&data->list, g_ptr_array_unref);
+	g_free (data);
+}
diff --git a/lib/gs-plugin-helpers.h b/lib/gs-plugin-helpers.h
new file mode 100644
index 0000000..b4a19f3
--- /dev/null
+++ b/lib/gs-plugin-helpers.h
@@ -0,0 +1,96 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <gio/gio.h>
+#include <glib.h>
+#include <glib-object.h>
+
+#include <gnome-software.h>
+
+G_BEGIN_DECLS
+
+typedef struct {
+	GsAppList *list;  /* (owned) (not nullable) */
+	GsPluginRefineFlags flags;
+} GsPluginRefineData;
+
+GsPluginRefineData *gs_plugin_refine_data_new (GsAppList           *list,
+                                               GsPluginRefineFlags  flags);
+GTask *gs_plugin_refine_data_new_task (gpointer             source_object,
+                                       GsAppList           *list,
+                                       GsPluginRefineFlags  flags,
+                                       GCancellable        *cancellable,
+                                       GAsyncReadyCallback  callback,
+                                       gpointer             user_data);
+void gs_plugin_refine_data_free (GsPluginRefineData *data);
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (GsPluginRefineData, gs_plugin_refine_data_free)
+
+typedef struct {
+	guint64 cache_age_secs;
+	GsPluginRefreshMetadataFlags flags;
+} GsPluginRefreshMetadataData;
+
+GsPluginRefreshMetadataData *gs_plugin_refresh_metadata_data_new (guint64                      cache_age_secs,
+                                                                  GsPluginRefreshMetadataFlags flags);
+void gs_plugin_refresh_metadata_data_free (GsPluginRefreshMetadataData *data);
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (GsPluginRefreshMetadataData, gs_plugin_refresh_metadata_data_free)
+
+typedef struct {
+	GsAppQuery *query;  /* (owned) (nullable) */
+	GsPluginListAppsFlags flags;
+} GsPluginListAppsData;
+
+GsPluginListAppsData *gs_plugin_list_apps_data_new (GsAppQuery            *query,
+                                                    GsPluginListAppsFlags  flags);
+GTask *gs_plugin_list_apps_data_new_task (gpointer               source_object,
+                                          GsAppQuery            *query,
+                                          GsPluginListAppsFlags  flags,
+                                          GCancellable          *cancellable,
+                                          GAsyncReadyCallback    callback,
+                                          gpointer               user_data);
+void gs_plugin_list_apps_data_free (GsPluginListAppsData *data);
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (GsPluginListAppsData, gs_plugin_list_apps_data_free)
+
+typedef struct {
+	GsApp *repository;  /* (owned) (nullable) */
+	GsPluginManageRepositoryFlags flags;
+} GsPluginManageRepositoryData;
+
+GsPluginManageRepositoryData *
+		gs_plugin_manage_repository_data_new		(GsApp				*repository,
+								 GsPluginManageRepositoryFlags   flags);
+GTask *		gs_plugin_manage_repository_data_new_task	(gpointer			 source_object,
+								 GsApp				*repository,
+								 GsPluginManageRepositoryFlags	 flags,
+								 GCancellable			*cancellable,
+								 GAsyncReadyCallback		 callback,
+								 gpointer			 user_data);
+void		gs_plugin_manage_repository_data_free		(GsPluginManageRepositoryData	*data);
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (GsPluginManageRepositoryData, gs_plugin_manage_repository_data_free)
+
+typedef struct {
+	GPtrArray *list;  /* (element-type GsCategory) (owned) (not nullable) */
+	GsPluginRefineCategoriesFlags flags;
+} GsPluginRefineCategoriesData;
+
+GsPluginRefineCategoriesData *gs_plugin_refine_categories_data_new (GPtrArray                     *list,
+                                                                    GsPluginRefineCategoriesFlags  flags);
+GTask *gs_plugin_refine_categories_data_new_task (gpointer                       source_object,
+                                                  GPtrArray                     *list,
+                                                  GsPluginRefineCategoriesFlags  flags,
+                                                  GCancellable                  *cancellable,
+                                                  GAsyncReadyCallback            callback,
+                                                  gpointer                       user_data);
+void gs_plugin_refine_categories_data_free (GsPluginRefineCategoriesData *data);
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (GsPluginRefineCategoriesData, gs_plugin_refine_categories_data_free)
+
+G_END_DECLS
diff --git a/lib/gs-plugin-job-list-apps.c b/lib/gs-plugin-job-list-apps.c
new file mode 100644
index 0000000..56a4e14
--- /dev/null
+++ b/lib/gs-plugin-job-list-apps.c
@@ -0,0 +1,516 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2022 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-plugin-job-list-apps
+ * @short_description: A plugin job to list apps according to a search query
+ *
+ * #GsPluginJobListApps is a #GsPluginJob representing an operation to
+ * list apps which match a given query, from all #GsPlugins.
+ *
+ * The known properties on the set of apps returned by this operation can be
+ * controlled with the #GsAppQuery:refine-flags property of the query. All
+ * results will be refined using the given set of refine flags. See
+ * #GsPluginJobRefine.
+ *
+ * This class is a wrapper around #GsPluginClass.list_apps_async,
+ * calling it for all loaded plugins, with #GsPluginJobRefine used to refine
+ * them.
+ *
+ * Retrieve the resulting #GsAppList using
+ * gs_plugin_job_list_apps_get_result_list().
+ *
+ * See also: #GsPluginClass.list_apps_async
+ * Since: 43
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <glib-object.h>
+
+#include "gs-app.h"
+#include "gs-app-list-private.h"
+#include "gs-app-query.h"
+#include "gs-enums.h"
+#include "gs-plugin-job.h"
+#include "gs-plugin-job-list-apps.h"
+#include "gs-plugin-job-private.h"
+#include "gs-plugin-job-refine.h"
+#include "gs-plugin-private.h"
+#include "gs-plugin-types.h"
+#include "gs-utils.h"
+
+struct _GsPluginJobListApps
+{
+	GsPluginJob parent;
+
+	/* Input arguments. */
+	GsAppQuery *query;  /* (owned) (nullable) */
+	GsPluginListAppsFlags flags;
+
+	/* In-progress data. */
+	GsAppList *merged_list;  /* (owned) (nullable) */
+	GError *saved_error;  /* (owned) (nullable) */
+	guint n_pending_ops;
+
+	/* Results. */
+	GsAppList *result_list;  /* (owned) (nullable) */
+};
+
+G_DEFINE_TYPE (GsPluginJobListApps, gs_plugin_job_list_apps, GS_TYPE_PLUGIN_JOB)
+
+typedef enum {
+	PROP_QUERY = 1,
+	PROP_FLAGS,
+} GsPluginJobListAppsProperty;
+
+static GParamSpec *props[PROP_FLAGS + 1] = { NULL, };
+
+static void
+gs_plugin_job_list_apps_dispose (GObject *object)
+{
+	GsPluginJobListApps *self = GS_PLUGIN_JOB_LIST_APPS (object);
+
+	g_assert (self->merged_list == NULL);
+	g_assert (self->saved_error == NULL);
+	g_assert (self->n_pending_ops == 0);
+
+	g_clear_object (&self->result_list);
+	g_clear_object (&self->query);
+
+	G_OBJECT_CLASS (gs_plugin_job_list_apps_parent_class)->dispose (object);
+}
+
+static void
+gs_plugin_job_list_apps_get_property (GObject    *object,
+                                      guint       prop_id,
+                                      GValue     *value,
+                                      GParamSpec *pspec)
+{
+	GsPluginJobListApps *self = GS_PLUGIN_JOB_LIST_APPS (object);
+
+	switch ((GsPluginJobListAppsProperty) prop_id) {
+	case PROP_QUERY:
+		g_value_set_object (value, self->query);
+		break;
+	case PROP_FLAGS:
+		g_value_set_flags (value, self->flags);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_plugin_job_list_apps_set_property (GObject      *object,
+                                      guint         prop_id,
+                                      const GValue *value,
+                                      GParamSpec   *pspec)
+{
+	GsPluginJobListApps *self = GS_PLUGIN_JOB_LIST_APPS (object);
+
+	switch ((GsPluginJobListAppsProperty) prop_id) {
+	case PROP_QUERY:
+		/* Construct only. */
+		g_assert (self->query == NULL);
+		self->query = g_value_dup_object (value);
+		g_object_notify_by_pspec (object, props[prop_id]);
+		break;
+	case PROP_FLAGS:
+		/* Construct only. */
+		g_assert (self->flags == 0);
+		self->flags = g_value_get_flags (value);
+		g_object_notify_by_pspec (object, props[prop_id]);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static gboolean
+filter_valid_apps (GsApp    *app,
+                   gpointer  user_data)
+{
+	GsPluginJobListApps *self = GS_PLUGIN_JOB_LIST_APPS (user_data);
+	GsPluginRefineFlags refine_flags = GS_PLUGIN_REFINE_FLAGS_NONE;
+
+	if (self->query)
+		refine_flags = gs_app_query_get_refine_flags (self->query);
+
+	return gs_plugin_loader_app_is_valid (app, refine_flags);
+}
+
+static gboolean
+app_filter_qt_for_gtk_and_compatible (GsApp    *app,
+                                      gpointer  user_data)
+{
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (user_data);
+
+	/* hide the QT versions in preference to the GTK ones */
+	if (g_strcmp0 (gs_app_get_id (app), "transmission-qt.desktop") == 0 ||
+	    g_strcmp0 (gs_app_get_id (app), "nntpgrab_qt.desktop") == 0 ||
+	    g_strcmp0 (gs_app_get_id (app), "gimagereader-qt4.desktop") == 0 ||
+	    g_strcmp0 (gs_app_get_id (app), "gimagereader-qt5.desktop") == 0 ||
+	    g_strcmp0 (gs_app_get_id (app), "nntpgrab_server_qt.desktop") == 0 ||
+	    g_strcmp0 (gs_app_get_id (app), "hotot-qt.desktop") == 0) {
+		g_debug ("removing QT version of %s",
+			 gs_app_get_unique_id (app));
+		return FALSE;
+	}
+
+	/* hide the KDE version in preference to the GTK one */
+	if (g_strcmp0 (gs_app_get_id (app), "qalculate_kde.desktop") == 0) {
+		g_debug ("removing KDE version of %s",
+			 gs_app_get_unique_id (app));
+		return FALSE;
+	}
+
+	/* hide the KDE version in preference to the Qt one */
+	if (g_strcmp0 (gs_app_get_id (app), "kid3.desktop") == 0 ||
+	    g_strcmp0 (gs_app_get_id (app), "kchmviewer.desktop") == 0) {
+		g_debug ("removing KDE version of %s",
+			 gs_app_get_unique_id (app));
+		return FALSE;
+	}
+
+	return gs_plugin_loader_app_is_compatible (plugin_loader, app);
+}
+
+static void plugin_list_apps_cb (GObject      *source_object,
+                                 GAsyncResult *result,
+                                 gpointer      user_data);
+static void finish_op (GTask  *task,
+                       GError *error);
+static void refine_cb (GObject      *source_object,
+                       GAsyncResult *result,
+                       gpointer      user_data);
+static void finish_task (GTask     *task,
+                         GsAppList *merged_list);
+
+static void
+gs_plugin_job_list_apps_run_async (GsPluginJob         *job,
+                                   GsPluginLoader      *plugin_loader,
+                                   GCancellable        *cancellable,
+                                   GAsyncReadyCallback  callback,
+                                   gpointer             user_data)
+{
+	GsPluginJobListApps *self = GS_PLUGIN_JOB_LIST_APPS (job);
+	g_autoptr(GTask) task = NULL;
+	GPtrArray *plugins;  /* (element-type GsPlugin) */
+	gboolean anything_ran = FALSE;
+
+	task = g_task_new (job, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_plugin_job_list_apps_run_async);
+	g_task_set_task_data (task, g_object_ref (plugin_loader), (GDestroyNotify) g_object_unref);
+
+	/* run each plugin, keeping a counter of pending operations which is
+	 * initialised to 1 until all the operations are started */
+	self->n_pending_ops = 1;
+	self->merged_list = gs_app_list_new ();
+	plugins = gs_plugin_loader_get_plugins (plugin_loader);
+
+	for (guint i = 0; i < plugins->len; i++) {
+		GsPlugin *plugin = g_ptr_array_index (plugins, i);
+		GsPluginClass *plugin_class = GS_PLUGIN_GET_CLASS (plugin);
+
+		if (!gs_plugin_get_enabled (plugin))
+			continue;
+		if (plugin_class->list_apps_async == NULL)
+			continue;
+
+		/* at least one plugin supports this vfunc */
+		anything_ran = TRUE;
+
+		/* run the plugin */
+		self->n_pending_ops++;
+		plugin_class->list_apps_async (plugin, self->query, self->flags, cancellable, plugin_list_apps_cb, g_object_ref (task));
+	}
+
+	if (!anything_ran)
+		g_debug ("no plugin could handle listing apps");
+
+	finish_op (task, NULL);
+}
+
+static void
+plugin_list_apps_cb (GObject      *source_object,
+                     GAsyncResult *result,
+                     gpointer      user_data)
+{
+	GsPlugin *plugin = GS_PLUGIN (source_object);
+	GsPluginClass *plugin_class = GS_PLUGIN_GET_CLASS (plugin);
+	g_autoptr(GTask) task = G_TASK (user_data);
+	GsPluginJobListApps *self = g_task_get_source_object (task);
+	g_autoptr(GsAppList) plugin_apps = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	plugin_apps = plugin_class->list_apps_finish (plugin, result, &local_error);
+	gs_plugin_status_update (plugin, NULL, GS_PLUGIN_STATUS_FINISHED);
+
+	if (plugin_apps != NULL)
+		gs_app_list_add_list (self->merged_list, plugin_apps);
+
+	/* Since #GsAppQuery supports a number of different query parameters,
+	 * not all plugins will support all of them. Ignore errors related to
+	 * that. */
+	if (g_error_matches (local_error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED))
+		g_clear_error (&local_error);
+
+	finish_op (task, g_steal_pointer (&local_error));
+}
+
+/* @error is (transfer full) if non-%NULL */
+static void
+finish_op (GTask  *task,
+           GError *error)
+{
+	GsPluginJobListApps *self = g_task_get_source_object (task);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+	GsPluginLoader *plugin_loader = g_task_get_task_data (task);
+	g_autoptr(GsAppList) merged_list = NULL;
+	GsPluginRefineFlags refine_flags = GS_PLUGIN_REFINE_FLAGS_NONE;
+	g_autoptr(GError) error_owned = g_steal_pointer (&error);
+
+	if (error_owned != NULL && self->saved_error == NULL)
+		self->saved_error = g_steal_pointer (&error_owned);
+	else if (error_owned != NULL)
+		g_debug ("Additional error while listing apps: %s", error_owned->message);
+
+	g_assert (self->n_pending_ops > 0);
+	self->n_pending_ops--;
+
+	if (self->n_pending_ops > 0)
+		return;
+
+	/* Get the results of the parallel ops. */
+	merged_list = g_steal_pointer (&self->merged_list);
+
+	if (self->saved_error != NULL) {
+		g_task_return_error (task, g_steal_pointer (&self->saved_error));
+		return;
+	}
+
+	/* run refine() on each one if required */
+	if (self->query != NULL)
+		refine_flags = gs_app_query_get_refine_flags (self->query);
+
+	if (merged_list != NULL &&
+	    gs_app_list_length (merged_list) > 0 &&
+	    refine_flags != GS_PLUGIN_REFINE_FLAGS_NONE) {
+		g_autoptr(GsPluginJob) refine_job = NULL;
+
+		refine_job = gs_plugin_job_refine_new (merged_list,
+						       refine_flags |
+						       GS_PLUGIN_REFINE_FLAGS_DISABLE_FILTERING);
+		gs_plugin_loader_job_process_async (plugin_loader, refine_job,
+						    cancellable,
+						    refine_cb,
+						    g_object_ref (task));
+	} else {
+		g_debug ("No apps to refine");
+		finish_task (task, merged_list);
+	}
+}
+
+static void
+refine_cb (GObject      *source_object,
+           GAsyncResult *result,
+           gpointer      user_data)
+{
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (source_object);
+	g_autoptr(GTask) task = G_TASK (user_data);
+	g_autoptr(GsAppList) new_list = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	new_list = gs_plugin_loader_job_process_finish (plugin_loader, result, &local_error);
+	if (new_list == NULL) {
+		gs_utils_error_convert_gio (&local_error);
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	finish_task (task, new_list);
+}
+
+static void
+finish_task (GTask     *task,
+             GsAppList *merged_list)
+{
+	GsPluginJobListApps *self = g_task_get_source_object (task);
+	GsPluginLoader *plugin_loader = g_task_get_task_data (task);
+	GsAppListFilterFlags dedupe_flags = GS_APP_LIST_FILTER_FLAG_NONE;
+	GsAppListSortFunc sort_func = NULL;
+	gpointer sort_func_data = NULL;
+	GsAppListFilterFunc filter_func = NULL;
+	gpointer filter_func_data = NULL;
+	guint max_results = 0;
+	g_autofree gchar *job_debug = NULL;
+
+	/* Standard filtering.
+	 *
+	 * FIXME: It feels like this filter should be done in a different layer. */
+	gs_app_list_filter (merged_list, filter_valid_apps, self);
+	gs_app_list_filter (merged_list, app_filter_qt_for_gtk_and_compatible, plugin_loader);
+
+	/* Caller-specified filtering. */
+	if (self->query != NULL)
+		filter_func = gs_app_query_get_filter_func (self->query, &filter_func_data);
+
+	if (filter_func != NULL)
+		gs_app_list_filter (merged_list, filter_func, filter_func_data);
+
+	/* Filter duplicates with priority, taking into account the source name
+	 * & version, so we combine available updates with the installed app */
+	if (self->query != NULL)
+		dedupe_flags = gs_app_query_get_dedupe_flags (self->query);
+
+	if (dedupe_flags != GS_APP_LIST_FILTER_FLAG_NONE)
+		gs_app_list_filter_duplicates (merged_list, dedupe_flags);
+
+	/* Sort the results. The refine may have added useful metadata. */
+	if (self->query != NULL)
+		sort_func = gs_app_query_get_sort_func (self->query, &sort_func_data);
+
+	if (sort_func != NULL) {
+		gs_app_list_sort (merged_list, sort_func, sort_func_data);
+	} else {
+		g_debug ("no ->sort_func() set, using random!");
+		gs_app_list_randomize (merged_list);
+	}
+
+	/* Truncate the results if needed. */
+	if (self->query != NULL)
+		max_results = gs_app_query_get_max_results (self->query);
+
+	if (max_results > 0 && gs_app_list_length (merged_list) > max_results) {
+		g_debug ("truncating results from %u to %u",
+			 gs_app_list_length (merged_list), max_results);
+		gs_app_list_truncate (merged_list, max_results);
+	}
+
+	/* show elapsed time */
+	job_debug = gs_plugin_job_to_string (GS_PLUGIN_JOB (self));
+	g_debug ("%s", job_debug);
+
+	/* Check the intermediate working values are all cleared. */
+	g_assert (self->merged_list == NULL);
+	g_assert (self->saved_error == NULL);
+	g_assert (self->n_pending_ops == 0);
+
+	/* success */
+	g_set_object (&self->result_list, merged_list);
+	g_task_return_boolean (task, TRUE);
+}
+
+static gboolean
+gs_plugin_job_list_apps_run_finish (GsPluginJob   *self,
+                                    GAsyncResult  *result,
+                                    GError       **error)
+{
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+static void
+gs_plugin_job_list_apps_class_init (GsPluginJobListAppsClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+	GsPluginJobClass *job_class = GS_PLUGIN_JOB_CLASS (klass);
+
+	object_class->dispose = gs_plugin_job_list_apps_dispose;
+	object_class->get_property = gs_plugin_job_list_apps_get_property;
+	object_class->set_property = gs_plugin_job_list_apps_set_property;
+
+	job_class->run_async = gs_plugin_job_list_apps_run_async;
+	job_class->run_finish = gs_plugin_job_list_apps_run_finish;
+
+	/**
+	 * GsPluginJobListApps:query: (nullable)
+	 *
+	 * A #GsAppQuery defining the query parameters.
+	 *
+	 * If this is %NULL, all apps will be returned.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_QUERY] =
+		g_param_spec_object ("query", "Query",
+				     "A #GsAppQuery defining the query parameters.",
+				     GS_TYPE_APP_QUERY,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				     G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPluginJobListApps:flags:
+	 *
+	 * Flags to specify how the operation should run.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_FLAGS] =
+		g_param_spec_flags ("flags", "Flags",
+				    "Flags to specify how the operation should run.",
+				    GS_TYPE_PLUGIN_LIST_APPS_FLAGS,
+				    GS_PLUGIN_LIST_APPS_FLAGS_NONE,
+				    G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				    G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	g_object_class_install_properties (object_class, G_N_ELEMENTS (props), props);
+}
+
+static void
+gs_plugin_job_list_apps_init (GsPluginJobListApps *self)
+{
+}
+
+/**
+ * gs_plugin_job_list_apps_new:
+ * @query: (nullable) (transfer none): query to affect which apps to return
+ * @flags: flags affecting how the operation runs
+ *
+ * Create a new #GsPluginJobListApps for listing apps according to the given
+ * @query.
+ *
+ * Returns: (transfer full): a new #GsPluginJobListApps
+ * Since: 43
+ */
+GsPluginJob *
+gs_plugin_job_list_apps_new (GsAppQuery            *query,
+                             GsPluginListAppsFlags  flags)
+{
+	g_return_val_if_fail (query == NULL || GS_IS_APP_QUERY (query), NULL);
+
+	return g_object_new (GS_TYPE_PLUGIN_JOB_LIST_APPS,
+			     "query", query,
+			     "flags", flags,
+			     NULL);
+}
+
+/**
+ * gs_plugin_job_list_apps_get_result_list:
+ * @self: a #GsPluginJobListApps
+ *
+ * Get the full list of apps matching the query.
+ *
+ * If this is called before the job is complete, %NULL will be returned.
+ *
+ * Returns: (transfer none) (nullable): the job results, or %NULL on error
+ *   or if called before the job has completed
+ * Since: 43
+ */
+GsAppList *
+gs_plugin_job_list_apps_get_result_list (GsPluginJobListApps *self)
+{
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB_LIST_APPS (self), NULL);
+
+	return self->result_list;
+}
diff --git a/lib/gs-plugin-job-list-apps.h b/lib/gs-plugin-job-list-apps.h
new file mode 100644
index 0000000..e6aec46
--- /dev/null
+++ b/lib/gs-plugin-job-list-apps.h
@@ -0,0 +1,31 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2022 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <glib-object.h>
+#include <gio/gio.h>
+
+#include "gs-app-query.h"
+#include "gs-plugin-job.h"
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_PLUGIN_JOB_LIST_APPS (gs_plugin_job_list_apps_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsPluginJobListApps, gs_plugin_job_list_apps, GS, PLUGIN_JOB_LIST_APPS, GsPluginJob)
+
+GsPluginJob	*gs_plugin_job_list_apps_new	(GsAppQuery            *query,
+						 GsPluginListAppsFlags  flags);
+
+GsAppList	*gs_plugin_job_list_apps_get_result_list	(GsPluginJobListApps *self);
+
+G_END_DECLS
diff --git a/lib/gs-plugin-job-list-categories.c b/lib/gs-plugin-job-list-categories.c
new file mode 100644
index 0000000..f2d1644
--- /dev/null
+++ b/lib/gs-plugin-job-list-categories.c
@@ -0,0 +1,347 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2022 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-plugin-job-list-categories
+ * @short_description: A plugin job to list categories
+ *
+ * #GsPluginJobListCategories is a #GsPluginJob representing an operation to
+ * list categories.
+ *
+ * All results will be refined using the given set of refine flags, similarly to
+ * how #GsPluginJobRefine refines apps.
+ *
+ * This class is a wrapper around #GsPluginClass.refine_categories_async,
+ * calling it for all loaded plugins on the list of categories exposed by a
+ * #GsCategoryManager.
+ *
+ * Retrieve the resulting #GPtrArray of #GsCategory objects using
+ * gs_plugin_job_list_categories_get_result_list().
+ *
+ * See also: #GsPluginClass.refine_categories_async
+ * Since: 43
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <glib-object.h>
+
+#include "gs-category.h"
+#include "gs-category-private.h"
+#include "gs-enums.h"
+#include "gs-plugin-job.h"
+#include "gs-plugin-job-list-categories.h"
+#include "gs-plugin-job-private.h"
+#include "gs-plugin-private.h"
+#include "gs-plugin-types.h"
+#include "gs-utils.h"
+
+struct _GsPluginJobListCategories
+{
+	GsPluginJob parent;
+
+	/* Input arguments. */
+	GsPluginRefineCategoriesFlags flags;
+
+	/* In-progress data. */
+	GPtrArray *category_list;  /* (element-type GsCategory) (owned) (nullable) */
+	GError *saved_error;  /* (owned) (nullable) */
+	guint n_pending_ops;
+
+	/* Results. */
+	GPtrArray *result_list;  /* (element-type GsCategory) (owned) (nullable) */
+};
+
+G_DEFINE_TYPE (GsPluginJobListCategories, gs_plugin_job_list_categories, GS_TYPE_PLUGIN_JOB)
+
+typedef enum {
+	PROP_FLAGS = 1,
+} GsPluginJobListCategoriesProperty;
+
+static GParamSpec *props[PROP_FLAGS + 1] = { NULL, };
+
+static void
+gs_plugin_job_list_categories_dispose (GObject *object)
+{
+	GsPluginJobListCategories *self = GS_PLUGIN_JOB_LIST_CATEGORIES (object);
+
+	g_assert (self->category_list == NULL);
+	g_assert (self->saved_error == NULL);
+	g_assert (self->n_pending_ops == 0);
+
+	g_clear_pointer (&self->result_list, g_ptr_array_unref);
+
+	G_OBJECT_CLASS (gs_plugin_job_list_categories_parent_class)->dispose (object);
+}
+
+static void
+gs_plugin_job_list_categories_get_property (GObject    *object,
+                                            guint       prop_id,
+                                            GValue     *value,
+                                            GParamSpec *pspec)
+{
+	GsPluginJobListCategories *self = GS_PLUGIN_JOB_LIST_CATEGORIES (object);
+
+	switch ((GsPluginJobListCategoriesProperty) prop_id) {
+	case PROP_FLAGS:
+		g_value_set_flags (value, self->flags);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_plugin_job_list_categories_set_property (GObject      *object,
+                                            guint         prop_id,
+                                            const GValue *value,
+                                            GParamSpec   *pspec)
+{
+	GsPluginJobListCategories *self = GS_PLUGIN_JOB_LIST_CATEGORIES (object);
+
+	switch ((GsPluginJobListCategoriesProperty) prop_id) {
+	case PROP_FLAGS:
+		/* Construct only. */
+		g_assert (self->flags == 0);
+		self->flags = g_value_get_flags (value);
+		g_object_notify_by_pspec (object, props[prop_id]);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void plugin_refine_categories_cb (GObject      *source_object,
+                                         GAsyncResult *result,
+                                         gpointer      user_data);
+static void finish_op (GTask  *task,
+                       GError *error);
+
+static void
+gs_plugin_job_list_categories_run_async (GsPluginJob         *job,
+                                         GsPluginLoader      *plugin_loader,
+                                         GCancellable        *cancellable,
+                                         GAsyncReadyCallback  callback,
+                                         gpointer             user_data)
+{
+	GsPluginJobListCategories *self = GS_PLUGIN_JOB_LIST_CATEGORIES (job);
+	g_autoptr(GTask) task = NULL;
+	GPtrArray *plugins;  /* (element-type GsPlugin) */
+	gboolean anything_ran = FALSE;
+	GsCategory * const *categories = NULL;
+	gsize n_categories;
+
+	task = g_task_new (job, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_plugin_job_list_categories_run_async);
+	g_task_set_task_data (task, g_object_ref (plugin_loader), (GDestroyNotify) g_object_unref);
+
+	/* get the categories */
+	categories = gs_category_manager_get_categories (gs_plugin_loader_get_category_manager (plugin_loader), &n_categories);
+	self->category_list = g_ptr_array_new_full (n_categories, (GDestroyNotify) g_object_unref);
+
+	for (gsize i = 0; i < n_categories; i++)
+		g_ptr_array_add (self->category_list, g_object_ref (categories[i]));
+
+	/* run each plugin, keeping a counter of pending operations which is
+	 * initialised to 1 until all the operations are started */
+	self->n_pending_ops = 1;
+	plugins = gs_plugin_loader_get_plugins (plugin_loader);
+
+	for (guint i = 0; i < plugins->len; i++) {
+		GsPlugin *plugin = g_ptr_array_index (plugins, i);
+		GsPluginClass *plugin_class = GS_PLUGIN_GET_CLASS (plugin);
+
+		if (!gs_plugin_get_enabled (plugin))
+			continue;
+		if (plugin_class->refine_categories_async == NULL)
+			continue;
+
+		/* at least one plugin supports this vfunc */
+		anything_ran = TRUE;
+
+		/* run the plugin */
+		self->n_pending_ops++;
+		plugin_class->refine_categories_async (plugin, self->category_list, self->flags, cancellable, plugin_refine_categories_cb, g_object_ref (task));
+	}
+
+	if (!anything_ran)
+		g_debug ("no plugin could handle listing categories");
+
+	finish_op (task, NULL);
+}
+
+static void
+plugin_refine_categories_cb (GObject      *source_object,
+                             GAsyncResult *result,
+                             gpointer      user_data)
+{
+	GsPlugin *plugin = GS_PLUGIN (source_object);
+	GsPluginClass *plugin_class = GS_PLUGIN_GET_CLASS (plugin);
+	g_autoptr(GTask) task = G_TASK (user_data);
+	g_autoptr(GError) local_error = NULL;
+
+	if (!plugin_class->refine_categories_finish (plugin, result, &local_error)) {
+		finish_op (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	gs_plugin_status_update (plugin, NULL, GS_PLUGIN_STATUS_FINISHED);
+
+	finish_op (task, g_steal_pointer (&local_error));
+}
+
+static gint
+category_sort_cb (gconstpointer a,
+                  gconstpointer b)
+{
+	GsCategory *category_a = GS_CATEGORY (*(GsCategory **) a);
+	GsCategory *category_b = GS_CATEGORY (*(GsCategory **) b);
+	gint score_a = gs_category_get_score (category_a);
+	gint score_b = gs_category_get_score (category_b);
+
+	if (score_a != score_b)
+		return score_b - score_a;
+	return gs_utils_sort_strcmp (gs_category_get_name (category_a),
+				     gs_category_get_name (category_b));
+}
+
+/* @error is (transfer full) if non-%NULL */
+static void
+finish_op (GTask  *task,
+           GError *error)
+{
+	GsPluginJobListCategories *self = g_task_get_source_object (task);
+	g_autoptr(GPtrArray) category_list = NULL;
+	g_autoptr(GError) error_owned = g_steal_pointer (&error);
+	g_autofree gchar *job_debug = NULL;
+
+	if (error_owned != NULL && self->saved_error == NULL)
+		self->saved_error = g_steal_pointer (&error_owned);
+	else if (error_owned != NULL)
+		g_debug ("Additional error while listing categories: %s", error_owned->message);
+
+	g_assert (self->n_pending_ops > 0);
+	self->n_pending_ops--;
+
+	if (self->n_pending_ops > 0)
+		return;
+
+	/* Get the results of the parallel ops. */
+	category_list = g_steal_pointer (&self->category_list);
+
+	if (self->saved_error != NULL) {
+		g_task_return_error (task, g_steal_pointer (&self->saved_error));
+		return;
+	}
+
+	/* sort by name */
+	g_ptr_array_sort (category_list, category_sort_cb);
+	for (guint i = 0; i < category_list->len; i++) {
+		GsCategory *category = GS_CATEGORY (g_ptr_array_index (category_list, i));
+		gs_category_sort_children (category);
+	}
+
+	/* show elapsed time */
+	job_debug = gs_plugin_job_to_string (GS_PLUGIN_JOB (self));
+	g_debug ("%s", job_debug);
+
+	/* Check the intermediate working values are all cleared. */
+	g_assert (self->category_list == NULL);
+	g_assert (self->saved_error == NULL);
+	g_assert (self->n_pending_ops == 0);
+
+	/* success */
+	self->result_list = g_ptr_array_ref (category_list);
+	g_task_return_boolean (task, TRUE);
+}
+
+static gboolean
+gs_plugin_job_list_categories_run_finish (GsPluginJob   *self,
+                                          GAsyncResult  *result,
+                                          GError       **error)
+{
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+static void
+gs_plugin_job_list_categories_class_init (GsPluginJobListCategoriesClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+	GsPluginJobClass *job_class = GS_PLUGIN_JOB_CLASS (klass);
+
+	object_class->dispose = gs_plugin_job_list_categories_dispose;
+	object_class->get_property = gs_plugin_job_list_categories_get_property;
+	object_class->set_property = gs_plugin_job_list_categories_set_property;
+
+	job_class->run_async = gs_plugin_job_list_categories_run_async;
+	job_class->run_finish = gs_plugin_job_list_categories_run_finish;
+
+	/**
+	 * GsPluginJobListCategories:flags:
+	 *
+	 * Flags to specify how the operation should run.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_FLAGS] =
+		g_param_spec_flags ("flags", "Flags",
+				    "Flags to specify how the operation should run.",
+				    GS_TYPE_PLUGIN_REFINE_CATEGORIES_FLAGS,
+				    GS_PLUGIN_REFINE_CATEGORIES_FLAGS_NONE,
+				    G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				    G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	g_object_class_install_properties (object_class, G_N_ELEMENTS (props), props);
+}
+
+static void
+gs_plugin_job_list_categories_init (GsPluginJobListCategories *self)
+{
+}
+
+/**
+ * gs_plugin_job_list_categories_new:
+ * @flags: flags affecting how the operation runs
+ *
+ * Create a new #GsPluginJobListCategories for listing categories.
+ *
+ * Returns: (transfer full): a new #GsPluginJobListCategories
+ * Since: 43
+ */
+GsPluginJob *
+gs_plugin_job_list_categories_new (GsPluginRefineCategoriesFlags flags)
+{
+	return g_object_new (GS_TYPE_PLUGIN_JOB_LIST_CATEGORIES,
+			     "flags", flags,
+			     NULL);
+}
+
+/**
+ * gs_plugin_job_list_categories_get_result_list:
+ * @self: a #GsPluginJobListCategories
+ *
+ * Get the full list of categories.
+ *
+ * If this is called before the job is complete, %NULL will be returned.
+ *
+ * Returns: (transfer none) (nullable) (element-type GsCategory): the job
+ *   results, or %NULL on error or if called before the job has completed
+ * Since: 43
+ */
+GPtrArray *
+gs_plugin_job_list_categories_get_result_list (GsPluginJobListCategories *self)
+{
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB_LIST_CATEGORIES (self), NULL);
+
+	return self->result_list;
+}
diff --git a/lib/gs-plugin-job-list-categories.h b/lib/gs-plugin-job-list-categories.h
new file mode 100644
index 0000000..49857f3
--- /dev/null
+++ b/lib/gs-plugin-job-list-categories.h
@@ -0,0 +1,29 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2022 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <glib-object.h>
+#include <gio/gio.h>
+
+#include "gs-plugin-job.h"
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_PLUGIN_JOB_LIST_CATEGORIES (gs_plugin_job_list_categories_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsPluginJobListCategories, gs_plugin_job_list_categories, GS, PLUGIN_JOB_LIST_CATEGORIES, GsPluginJob)
+
+GsPluginJob	*gs_plugin_job_list_categories_new		(GsPluginRefineCategoriesFlags flags);
+
+GPtrArray	*gs_plugin_job_list_categories_get_result_list	(GsPluginJobListCategories *self);
+
+G_END_DECLS
diff --git a/lib/gs-plugin-job-list-distro-upgrades.c b/lib/gs-plugin-job-list-distro-upgrades.c
new file mode 100644
index 0000000..618bb2a
--- /dev/null
+++ b/lib/gs-plugin-job-list-distro-upgrades.c
@@ -0,0 +1,428 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2022 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-plugin-job-list-distro-upgrades
+ * @short_description: A plugin job to list distro upgrades
+ *
+ * #GsPluginJobListDistroUpgrades is a #GsPluginJob representing an operation to
+ * list available upgrades for the distro, from all #GsPlugins.
+ *
+ * Upgrades for the distro are large upgrades, such as from Fedora 34 to
+ * Fedora 35. They are not small package updates.
+ *
+ * This job will list the available upgrades, but will not download them or
+ * install them. Due to the typical size of an upgrade, these should not be
+ * downloaded until the user has explicitly requested it.
+ *
+ * The known properties on the set of apps returned by this operation can be
+ * controlled with the #GsPluginJobListDistroUpgrades:refine-flags property. All
+ * results will be refined using %GS_PLUGIN_REFINE_FLAGS_REQUIRE_SETUP_ACTION
+ * plus the given set of refine flags. See #GsPluginJobRefine.
+ *
+ * This class is a wrapper around #GsPluginClass.list_distro_upgrades_async,
+ * calling it for all loaded plugins, with some additional filtering
+ * done on the results and #GsPluginJobRefine used to refine them.
+ *
+ * Retrieve the resulting #GsAppList using
+ * gs_plugin_job_list_distro_upgrades_get_result_list(). Components in the list
+ * are expected to be of type %AS_COMPONENT_KIND_OPERATING_SYSTEM.
+ *
+ * See also: #GsPluginClass.list_distro_upgrades_async
+ * Since: 42
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <glib-object.h>
+#include <glib/gi18n.h>
+
+#include "gs-app.h"
+#include "gs-app-list-private.h"
+#include "gs-enums.h"
+#include "gs-plugin-job-private.h"
+#include "gs-plugin-job-list-distro-upgrades.h"
+#include "gs-plugin-job-refine.h"
+#include "gs-plugin-private.h"
+#include "gs-plugin-types.h"
+#include "gs-utils.h"
+
+struct _GsPluginJobListDistroUpgrades
+{
+	GsPluginJob parent;
+
+	/* Input arguments. */
+	GsPluginListDistroUpgradesFlags flags;
+	GsPluginRefineFlags refine_flags;
+
+	/* In-progress data. */
+	GsAppList *merged_list;  /* (owned) (nullable) */
+	GError *saved_error;  /* (owned) (nullable) */
+	guint n_pending_ops;
+
+	/* Results. */
+	GsAppList *result_list;  /* (owned) (nullable) */
+};
+
+G_DEFINE_TYPE (GsPluginJobListDistroUpgrades, gs_plugin_job_list_distro_upgrades, GS_TYPE_PLUGIN_JOB)
+
+typedef enum {
+	PROP_REFINE_FLAGS = 1,
+	PROP_FLAGS,
+} GsPluginJobListDistroUpgradesProperty;
+
+static GParamSpec *props[PROP_FLAGS + 1] = { NULL, };
+
+static void
+gs_plugin_job_list_distro_upgrades_dispose (GObject *object)
+{
+	GsPluginJobListDistroUpgrades *self = GS_PLUGIN_JOB_LIST_DISTRO_UPGRADES (object);
+
+	g_assert (self->merged_list == NULL);
+	g_assert (self->saved_error == NULL);
+	g_assert (self->n_pending_ops == 0);
+
+	g_clear_object (&self->result_list);
+
+	G_OBJECT_CLASS (gs_plugin_job_list_distro_upgrades_parent_class)->dispose (object);
+}
+
+static void
+gs_plugin_job_list_distro_upgrades_get_property (GObject    *object,
+                                                 guint       prop_id,
+                                                 GValue     *value,
+                                                 GParamSpec *pspec)
+{
+	GsPluginJobListDistroUpgrades *self = GS_PLUGIN_JOB_LIST_DISTRO_UPGRADES (object);
+
+	switch ((GsPluginJobListDistroUpgradesProperty) prop_id) {
+	case PROP_REFINE_FLAGS:
+		g_value_set_flags (value, self->refine_flags);
+		break;
+	case PROP_FLAGS:
+		g_value_set_flags (value, self->flags);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_plugin_job_list_distro_upgrades_set_property (GObject      *object,
+                                                 guint         prop_id,
+                                                 const GValue *value,
+                                                 GParamSpec   *pspec)
+{
+	GsPluginJobListDistroUpgrades *self = GS_PLUGIN_JOB_LIST_DISTRO_UPGRADES (object);
+
+	switch ((GsPluginJobListDistroUpgradesProperty) prop_id) {
+	case PROP_REFINE_FLAGS:
+		/* Construct only. */
+		g_assert (self->refine_flags == 0);
+		self->refine_flags = g_value_get_flags (value);
+		g_object_notify_by_pspec (object, props[prop_id]);
+		break;
+	case PROP_FLAGS:
+		/* Construct only. */
+		g_assert (self->flags == 0);
+		self->flags = g_value_get_flags (value);
+		g_object_notify_by_pspec (object, props[prop_id]);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static gint
+app_sort_version_cb (GsApp    *app1,
+                     GsApp    *app2,
+                     gpointer  user_data)
+{
+	return as_vercmp_simple (gs_app_get_version (app1),
+				 gs_app_get_version (app2));
+}
+
+static void plugin_list_distro_upgrades_cb (GObject      *source_object,
+                                            GAsyncResult *result,
+                                            gpointer      user_data);
+static void finish_op (GTask  *task,
+                       GError *error);
+static void refine_cb (GObject      *source_object,
+                       GAsyncResult *result,
+                       gpointer      user_data);
+static void finish_task (GTask     *task,
+                         GsAppList *merged_list);
+
+static void
+gs_plugin_job_list_distro_upgrades_run_async (GsPluginJob         *job,
+                                              GsPluginLoader      *plugin_loader,
+                                              GCancellable        *cancellable,
+                                              GAsyncReadyCallback  callback,
+                                              gpointer             user_data)
+{
+	GsPluginJobListDistroUpgrades *self = GS_PLUGIN_JOB_LIST_DISTRO_UPGRADES (job);
+	g_autoptr(GTask) task = NULL;
+	GPtrArray *plugins;  /* (element-type GsPlugin) */
+	gboolean anything_ran = FALSE;
+
+	/* check required args */
+	task = g_task_new (job, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_plugin_job_list_distro_upgrades_run_async);
+	g_task_set_task_data (task, g_object_ref (plugin_loader), (GDestroyNotify) g_object_unref);
+
+	/* run each plugin, keeping a counter of pending operations which is
+	 * initialised to 1 until all the operations are started */
+	self->n_pending_ops = 1;
+	self->merged_list = gs_app_list_new ();
+	plugins = gs_plugin_loader_get_plugins (plugin_loader);
+
+	for (guint i = 0; i < plugins->len; i++) {
+		GsPlugin *plugin = g_ptr_array_index (plugins, i);
+		GsPluginClass *plugin_class = GS_PLUGIN_GET_CLASS (plugin);
+
+		if (!gs_plugin_get_enabled (plugin))
+			continue;
+		if (plugin_class->list_distro_upgrades_async == NULL)
+			continue;
+
+		/* at least one plugin supports this vfunc */
+		anything_ran = TRUE;
+
+		/* run the plugin */
+		self->n_pending_ops++;
+		plugin_class->list_distro_upgrades_async (plugin, self->flags, cancellable, plugin_list_distro_upgrades_cb, g_object_ref (task));
+	}
+
+	if (!anything_ran)
+		g_debug ("no plugin could handle listing distro upgrades");
+
+	finish_op (task, NULL);
+}
+
+static void
+plugin_list_distro_upgrades_cb (GObject      *source_object,
+                                GAsyncResult *result,
+                                gpointer      user_data)
+{
+	GsPlugin *plugin = GS_PLUGIN (source_object);
+	GsPluginClass *plugin_class = GS_PLUGIN_GET_CLASS (plugin);
+	g_autoptr(GTask) task = G_TASK (user_data);
+	GsPluginJobListDistroUpgrades *self = g_task_get_source_object (task);
+	g_autoptr(GsAppList) plugin_apps = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	plugin_apps = plugin_class->list_distro_upgrades_finish (plugin, result, &local_error);
+	gs_plugin_status_update (plugin, NULL, GS_PLUGIN_STATUS_FINISHED);
+
+	if (plugin_apps != NULL)
+		gs_app_list_add_list (self->merged_list, plugin_apps);
+
+	finish_op (task, g_steal_pointer (&local_error));
+}
+
+/* @error is (transfer full) if non-%NULL */
+static void
+finish_op (GTask  *task,
+           GError *error)
+{
+	GsPluginJobListDistroUpgrades *self = g_task_get_source_object (task);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+	GsPluginLoader *plugin_loader = g_task_get_task_data (task);
+	g_autoptr(GsAppList) merged_list = NULL;
+	g_autoptr(GError) error_owned = g_steal_pointer (&error);
+
+	if (error_owned != NULL && self->saved_error == NULL)
+		self->saved_error = g_steal_pointer (&error_owned);
+	else if (error_owned != NULL)
+		g_debug ("Additional error while listing distro upgrades: %s", error_owned->message);
+
+	g_assert (self->n_pending_ops > 0);
+	self->n_pending_ops--;
+
+	if (self->n_pending_ops > 0)
+		return;
+
+	/* Get the results of the parallel ops. */
+	merged_list = g_steal_pointer (&self->merged_list);
+
+	if (self->saved_error != NULL) {
+		g_task_return_error (task, g_steal_pointer (&self->saved_error));
+		return;
+	}
+
+	/* run refine() on each one if required */
+	if (merged_list != NULL &&
+	    gs_app_list_length (merged_list) > 0) {
+		g_autoptr(GsPluginJob) refine_job = NULL;
+
+		/* Always specify REQUIRE_SETUP_ACTION, as that requires enough
+		 * information to be able to install the upgrade later if
+		 * requested. */
+		refine_job = gs_plugin_job_refine_new (merged_list,
+						       self->refine_flags |
+						       GS_PLUGIN_REFINE_FLAGS_REQUIRE_SETUP_ACTION |
+						       GS_PLUGIN_REFINE_FLAGS_DISABLE_FILTERING);
+		gs_plugin_loader_job_process_async (plugin_loader, refine_job,
+						    cancellable,
+						    refine_cb,
+						    g_object_ref (task));
+	} else {
+		g_debug ("No distro upgrades to refine");
+		finish_task (task, merged_list);
+	}
+}
+
+static void
+refine_cb (GObject      *source_object,
+           GAsyncResult *result,
+           gpointer      user_data)
+{
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (source_object);
+	g_autoptr(GTask) task = G_TASK (user_data);
+	g_autoptr(GsAppList) new_list = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	new_list = gs_plugin_loader_job_process_finish (plugin_loader, result, &local_error);
+	if (new_list == NULL) {
+		gs_utils_error_convert_gio (&local_error);
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	finish_task (task, new_list);
+}
+
+static void
+finish_task (GTask     *task,
+             GsAppList *merged_list)
+{
+	GsPluginJobListDistroUpgrades *self = g_task_get_source_object (task);
+	g_autofree gchar *job_debug = NULL;
+
+	/* Sort the results. The refine may have added useful metadata. */
+	gs_app_list_sort (merged_list, app_sort_version_cb, NULL);
+
+	/* show elapsed time */
+	job_debug = gs_plugin_job_to_string (GS_PLUGIN_JOB (self));
+	g_debug ("%s", job_debug);
+
+	/* Check the intermediate working values are all cleared. */
+	g_assert (self->merged_list == NULL);
+	g_assert (self->saved_error == NULL);
+	g_assert (self->n_pending_ops == 0);
+
+	/* success */
+	g_set_object (&self->result_list, merged_list);
+	g_task_return_boolean (task, TRUE);
+}
+
+static gboolean
+gs_plugin_job_list_distro_upgrades_run_finish (GsPluginJob   *self,
+                                               GAsyncResult  *result,
+                                               GError       **error)
+{
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+static void
+gs_plugin_job_list_distro_upgrades_class_init (GsPluginJobListDistroUpgradesClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+	GsPluginJobClass *job_class = GS_PLUGIN_JOB_CLASS (klass);
+
+	object_class->dispose = gs_plugin_job_list_distro_upgrades_dispose;
+	object_class->get_property = gs_plugin_job_list_distro_upgrades_get_property;
+	object_class->set_property = gs_plugin_job_list_distro_upgrades_set_property;
+
+	job_class->run_async = gs_plugin_job_list_distro_upgrades_run_async;
+	job_class->run_finish = gs_plugin_job_list_distro_upgrades_run_finish;
+
+	/**
+	 * GsPluginJobListDistroUpgrades:refine-flags:
+	 *
+	 * Flags to specify how to refine the returned apps.
+	 *
+	 * %GS_PLUGIN_REFINE_FLAGS_REQUIRE_SETUP_ACTION will always be used.
+	 *
+	 * Since: 42
+	 */
+	props[PROP_REFINE_FLAGS] =
+		g_param_spec_flags ("refine-flags", "Refine Flags",
+				    "Flags to specify how to refine the returned apps.",
+				    GS_TYPE_PLUGIN_REFINE_FLAGS, GS_PLUGIN_REFINE_FLAGS_NONE,
+				    G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				    G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPluginJobListDistroUpgrades:flags:
+	 *
+	 * Flags to specify how the operation should run.
+	 *
+	 * Since: 42
+	 */
+	props[PROP_FLAGS] =
+		g_param_spec_flags ("flags", "Flags",
+				    "Flags to specify how the operation should run.",
+				    GS_TYPE_PLUGIN_LIST_DISTRO_UPGRADES_FLAGS,
+				    GS_PLUGIN_LIST_DISTRO_UPGRADES_FLAGS_NONE,
+				    G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				    G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	g_object_class_install_properties (object_class, G_N_ELEMENTS (props), props);
+}
+
+static void
+gs_plugin_job_list_distro_upgrades_init (GsPluginJobListDistroUpgrades *self)
+{
+}
+
+/**
+ * gs_plugin_job_list_distro_upgrades_new:
+ * @flags: flags affecting how the operation runs
+ * @refine_flags: flags to affect how the results are refined
+ *
+ * Create a new #GsPluginJobListDistroUpgrades for listing the available distro
+ * upgrades.
+ *
+ * Returns: (transfer full): a new #GsPluginJobListDistroUpgrades
+ * Since: 42
+ */
+GsPluginJob *
+gs_plugin_job_list_distro_upgrades_new (GsPluginListDistroUpgradesFlags flags,
+                                        GsPluginRefineFlags             refine_flags)
+{
+	return g_object_new (GS_TYPE_PLUGIN_JOB_LIST_DISTRO_UPGRADES,
+			     "refine-flags", refine_flags,
+			     "flags", flags,
+			     NULL);
+}
+
+/**
+ * gs_plugin_job_list_distro_upgrades_get_result_list:
+ * @self: a #GsPluginJobListDistroUpgrades
+ *
+ * Get the full list of available distro upgrades.
+ *
+ * If this is called before the job is complete, %NULL will be returned.
+ *
+ * Returns: (transfer none) (nullable): the job results, or %NULL on error
+ *   or if called before the job has completed
+ * Since: 42
+ */
+GsAppList *
+gs_plugin_job_list_distro_upgrades_get_result_list (GsPluginJobListDistroUpgrades *self)
+{
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB_LIST_DISTRO_UPGRADES (self), NULL);
+
+	return self->result_list;
+}
diff --git a/lib/gs-plugin-job-list-distro-upgrades.h b/lib/gs-plugin-job-list-distro-upgrades.h
new file mode 100644
index 0000000..0d3b0a2
--- /dev/null
+++ b/lib/gs-plugin-job-list-distro-upgrades.h
@@ -0,0 +1,30 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2022 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <glib-object.h>
+#include <gio/gio.h>
+
+#include "gs-plugin-job.h"
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_PLUGIN_JOB_LIST_DISTRO_UPGRADES (gs_plugin_job_list_distro_upgrades_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsPluginJobListDistroUpgrades, gs_plugin_job_list_distro_upgrades, GS, PLUGIN_JOB_LIST_DISTRO_UPGRADES, GsPluginJob)
+
+GsPluginJob	*gs_plugin_job_list_distro_upgrades_new	(GsPluginListDistroUpgradesFlags flags,
+							 GsPluginRefineFlags             refine_flags);
+
+GsAppList	*gs_plugin_job_list_distro_upgrades_get_result_list	(GsPluginJobListDistroUpgrades *self);
+
+G_END_DECLS
diff --git a/lib/gs-plugin-job-manage-repository.c b/lib/gs-plugin-job-manage-repository.c
new file mode 100644
index 0000000..2b8ee66
--- /dev/null
+++ b/lib/gs-plugin-job-manage-repository.c
@@ -0,0 +1,365 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2022 Red Hat <www.redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-plugin-job-manage-repository
+ * @short_description: A plugin job on a repository
+ *
+ * #GsPluginJobManageRepository is a #GsPluginJob representing an operation on
+ * a repository, like install, remove, enable and disable it.
+ *
+ * This class is a wrapper around #GsPluginClass.install_repository_async,
+ * #GsPluginClass.remove_repository_async, #GsPluginClass.enable_repository_async
+ * and #GsPluginClass.disable_repository_async calling it for all loaded plugins.
+ *
+ * Since: 43
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <glib-object.h>
+
+#include "gs-app.h"
+#include "gs-app-collation.h"
+#include "gs-enums.h"
+#include "gs-plugin-job.h"
+#include "gs-plugin-job-manage-repository.h"
+#include "gs-plugin-job-private.h"
+#include "gs-plugin-types.h"
+
+struct _GsPluginJobManageRepository
+{
+	GsPluginJob parent;
+
+	/* Input arguments. */
+	GsApp *repository;  /* (owned) (not nullable) */
+	GsPluginManageRepositoryFlags flags;
+
+	/* In-progress data. */
+	GError *saved_error;  /* (owned) (nullable) */
+	guint n_pending_ops;
+};
+
+G_DEFINE_TYPE (GsPluginJobManageRepository, gs_plugin_job_manage_repository, GS_TYPE_PLUGIN_JOB)
+
+typedef enum {
+	PROP_FLAGS = 1,
+	PROP_REPOSITORY,
+} GsPluginJobManageRepositoryProperty;
+
+static GParamSpec *props[PROP_REPOSITORY + 1] = { NULL, };
+
+static void
+gs_plugin_job_manage_repository_dispose (GObject *object)
+{
+	GsPluginJobManageRepository *self = GS_PLUGIN_JOB_MANAGE_REPOSITORY (object);
+
+	g_assert (self->saved_error == NULL);
+	g_assert (self->n_pending_ops == 0);
+
+	g_clear_object (&self->repository);
+
+	G_OBJECT_CLASS (gs_plugin_job_manage_repository_parent_class)->dispose (object);
+}
+
+static void
+gs_plugin_job_manage_repository_get_property (GObject    *object,
+					      guint       prop_id,
+					      GValue     *value,
+					      GParamSpec *pspec)
+{
+	GsPluginJobManageRepository *self = GS_PLUGIN_JOB_MANAGE_REPOSITORY (object);
+
+	switch ((GsPluginJobManageRepositoryProperty) prop_id) {
+	case PROP_FLAGS:
+		g_value_set_flags (value, self->flags);
+		break;
+	case PROP_REPOSITORY:
+		g_value_set_object (value, self->repository);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_plugin_job_manage_repository_set_property (GObject      *object,
+					      guint         prop_id,
+					      const GValue *value,
+					      GParamSpec   *pspec)
+{
+	GsPluginJobManageRepository *self = GS_PLUGIN_JOB_MANAGE_REPOSITORY (object);
+
+	switch ((GsPluginJobManageRepositoryProperty) prop_id) {
+	case PROP_FLAGS:
+		/* Construct only. */
+		g_assert (self->flags == 0);
+		self->flags = g_value_get_flags (value);
+		g_object_notify_by_pspec (object, props[prop_id]);
+		break;
+	case PROP_REPOSITORY:
+		/* Construct only. */
+		g_assert (self->repository == NULL);
+		self->repository = g_value_dup_object (value);
+		g_assert (self->repository != NULL);
+		g_object_notify_by_pspec (object, props[prop_id]);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void plugin_repository_func_cb (GObject      *source_object,
+				       GAsyncResult *result,
+				       gpointer      user_data);
+static void finish_op (GTask  *task,
+                       GError *error);
+
+static void
+gs_plugin_job_manage_repository_run_async (GsPluginJob         *job,
+					   GsPluginLoader      *plugin_loader,
+					   GCancellable        *cancellable,
+					   GAsyncReadyCallback  callback,
+					   gpointer             user_data)
+{
+	GsPluginJobManageRepository *self = GS_PLUGIN_JOB_MANAGE_REPOSITORY (job);
+	g_autoptr(GTask) task = NULL;
+	GPtrArray *plugins;  /* (element-type GsPlugin) */
+	gboolean anything_ran = FALSE;
+
+	task = g_task_new (job, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_plugin_job_manage_repository_run_async);
+	g_task_set_task_data (task, g_object_ref (plugin_loader), (GDestroyNotify) g_object_unref);
+
+	/* run each plugin, keeping a counter of pending operations which is
+	 * initialised to 1 until all the operations are started */
+	self->n_pending_ops = 1;
+	plugins = gs_plugin_loader_get_plugins (plugin_loader);
+
+	for (guint i = 0; i < plugins->len; i++) {
+		GsPlugin *plugin = g_ptr_array_index (plugins, i);
+		GsPluginClass *plugin_class = GS_PLUGIN_GET_CLASS (plugin);
+		void (* repository_func_async) (GsPlugin *plugin,
+						GsApp *repository,
+						GsPluginManageRepositoryFlags flags,
+						GCancellable *cancellable,
+						GAsyncReadyCallback callback,
+						gpointer user_data) = NULL;
+
+		if (!gs_plugin_get_enabled (plugin))
+			continue;
+		if ((self->flags & GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_INSTALL) != 0)
+			repository_func_async = plugin_class->install_repository_async;
+		else if ((self->flags & GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_REMOVE) != 0)
+			repository_func_async = plugin_class->remove_repository_async;
+		else if ((self->flags & GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_ENABLE) != 0)
+			repository_func_async = plugin_class->enable_repository_async;
+		else if ((self->flags & GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_DISABLE) != 0)
+			repository_func_async = plugin_class->disable_repository_async;
+		else
+			g_assert_not_reached ();
+
+		if (repository_func_async == NULL)
+			continue;
+
+		/* at least one plugin supports this vfunc */
+		anything_ran = TRUE;
+
+		/* run the plugin */
+		self->n_pending_ops++;
+		repository_func_async (plugin, self->repository, self->flags, cancellable, plugin_repository_func_cb, g_object_ref (task));
+	}
+
+	if (!anything_ran)
+		g_debug ("no plugin could handle repository operation");
+
+	finish_op (task, NULL);
+}
+
+static void
+plugin_repository_func_cb (GObject      *source_object,
+			   GAsyncResult *result,
+			   gpointer      user_data)
+{
+	GsPlugin *plugin = GS_PLUGIN (source_object);
+	GsPluginClass *plugin_class = GS_PLUGIN_GET_CLASS (plugin);
+	g_autoptr(GTask) task = G_TASK (user_data);
+	GsPluginJobManageRepository *self = g_task_get_source_object (task);
+	gboolean success;
+	g_autoptr(GError) local_error = NULL;
+	gboolean (* repository_func_finish) (GsPlugin *plugin,
+					     GAsyncResult *result,
+					     GError **error) = NULL;
+
+	if ((self->flags & GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_INSTALL) != 0)
+		repository_func_finish = plugin_class->install_repository_finish;
+	else if ((self->flags & GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_REMOVE) != 0)
+		repository_func_finish = plugin_class->remove_repository_finish;
+	else if ((self->flags & GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_ENABLE) != 0)
+		repository_func_finish = plugin_class->enable_repository_finish;
+	else if ((self->flags & GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_DISABLE) != 0)
+		repository_func_finish = plugin_class->disable_repository_finish;
+	else
+		g_assert_not_reached ();
+
+	success = repository_func_finish (plugin, result, &local_error);
+	gs_plugin_status_update (plugin, NULL, GS_PLUGIN_STATUS_FINISHED);
+
+	g_assert (success || local_error != NULL);
+
+	finish_op (task, g_steal_pointer (&local_error));
+}
+
+static void
+reset_app_progress (GsApp *app)
+{
+	g_autoptr(GsAppList) addons = gs_app_dup_addons (app);
+	GsAppList *related = gs_app_get_related (app);
+
+	gs_app_set_progress (app, GS_APP_PROGRESS_UNKNOWN);
+
+	for (guint i = 0; addons != NULL && i < gs_app_list_length (addons); i++) {
+		GsApp *app_addons = gs_app_list_index (addons, i);
+		gs_app_set_progress (app_addons, GS_APP_PROGRESS_UNKNOWN);
+	}
+	for (guint i = 0; i < gs_app_list_length (related); i++) {
+		GsApp *app_related = gs_app_list_index (related, i);
+		gs_app_set_progress (app_related, GS_APP_PROGRESS_UNKNOWN);
+	}
+}
+
+/* @error is (transfer full) if non-%NULL */
+static void
+finish_op (GTask  *task,
+           GError *error)
+{
+	GsPluginJobManageRepository *self = g_task_get_source_object (task);
+	g_autoptr(GError) error_owned = g_steal_pointer (&error);
+	g_autofree gchar *job_debug = NULL;
+
+	if (error_owned != NULL && self->saved_error == NULL)
+		self->saved_error = g_steal_pointer (&error_owned);
+	else if (error_owned != NULL)
+		g_debug ("Additional error while managing repository: %s", error_owned->message);
+
+	g_assert (self->n_pending_ops > 0);
+	self->n_pending_ops--;
+
+	if (self->n_pending_ops > 0)
+		return;
+
+	/* show elapsed time */
+	job_debug = gs_plugin_job_to_string (GS_PLUGIN_JOB (self));
+	g_debug ("%s", job_debug);
+
+	reset_app_progress (self->repository);
+
+	if (self->saved_error != NULL)
+		g_task_return_error (task, g_steal_pointer (&self->saved_error));
+	else
+		g_task_return_boolean (task, TRUE);
+}
+
+static gboolean
+gs_plugin_job_manage_repository_run_finish (GsPluginJob   *self,
+					    GAsyncResult  *result,
+					    GError       **error)
+{
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+static void
+gs_plugin_job_manage_repository_class_init (GsPluginJobManageRepositoryClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+	GsPluginJobClass *job_class = GS_PLUGIN_JOB_CLASS (klass);
+
+	object_class->dispose = gs_plugin_job_manage_repository_dispose;
+	object_class->get_property = gs_plugin_job_manage_repository_get_property;
+	object_class->set_property = gs_plugin_job_manage_repository_set_property;
+
+	job_class->run_async = gs_plugin_job_manage_repository_run_async;
+	job_class->run_finish = gs_plugin_job_manage_repository_run_finish;
+
+	/**
+	 * GsPluginJobManageRepository:repository: (not nullable)
+	 *
+	 * A #GsApp describing the repository to run the operation on.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_REPOSITORY] =
+		g_param_spec_object ("repository", "Repository",
+				     "A #GsApp describing the repository to run the operation on.",
+				     GS_TYPE_APP,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				     G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPluginJobManageRepository:flags:
+	 *
+	 * Flags to specify how and which the operation should run.
+	 * Only one of the %GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_INSTALL,
+	 * %GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_REMOVE, %GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_ENABLE and
+	 * %GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_DISABLE can be specified.
+	 *
+	 * Since: 43
+	 */
+	props[PROP_FLAGS] =
+		g_param_spec_flags ("flags", "Flags",
+				    "Flags to specify how and which the operation should run.",
+				    GS_TYPE_PLUGIN_MANAGE_REPOSITORY_FLAGS,
+				    GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_NONE,
+				    G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				    G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	g_object_class_install_properties (object_class, G_N_ELEMENTS (props), props);
+}
+
+static void
+gs_plugin_job_manage_repository_init (GsPluginJobManageRepository *self)
+{
+}
+
+/**
+ * gs_plugin_job_manage_repository_new:
+ * @repository: (not nullable) (transfer none): a repository to run the operation on
+ * @flags: flags affecting how the operation runs
+ *
+ * Create a new #GsPluginJobManageRepository to manage the given @repository.
+ *
+ * Returns: (transfer full): a new #GsPluginJobManageRepository
+ * Since: 43
+ */
+GsPluginJob *
+gs_plugin_job_manage_repository_new (GsApp			   *repository,
+				     GsPluginManageRepositoryFlags  flags)
+{
+	guint nops = 0;
+
+	g_return_val_if_fail (GS_IS_APP (repository), NULL);
+
+	if ((flags & GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_INSTALL) != 0)
+		nops++;
+	if ((flags & GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_REMOVE) != 0)
+		nops++;
+	if ((flags & GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_ENABLE) != 0)
+		nops++;
+	if ((flags & GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_DISABLE) != 0)
+		nops++;
+
+	g_return_val_if_fail (nops == 1, NULL);
+
+	return g_object_new (GS_TYPE_PLUGIN_JOB_MANAGE_REPOSITORY,
+			     "repository", repository,
+			     "flags", flags,
+			     NULL);
+}
diff --git a/lib/gs-plugin-job-manage-repository.h b/lib/gs-plugin-job-manage-repository.h
new file mode 100644
index 0000000..86233b7
--- /dev/null
+++ b/lib/gs-plugin-job-manage-repository.h
@@ -0,0 +1,26 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2022 Red Hat <www.redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <glib-object.h>
+#include <gio/gio.h>
+
+#include "gs-plugin-job.h"
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_PLUGIN_JOB_MANAGE_REPOSITORY (gs_plugin_job_manage_repository_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsPluginJobManageRepository, gs_plugin_job_manage_repository, GS, PLUGIN_JOB_MANAGE_REPOSITORY, GsPluginJob)
+
+GsPluginJob	*gs_plugin_job_manage_repository_new	(GsApp				 *repository,
+							 GsPluginManageRepositoryFlags	  flags);
+
+G_END_DECLS
diff --git a/lib/gs-plugin-job-private.h b/lib/gs-plugin-job-private.h
new file mode 100644
index 0000000..9cdbbf3
--- /dev/null
+++ b/lib/gs-plugin-job-private.h
@@ -0,0 +1,40 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2017 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib-object.h>
+
+#include "gs-plugin-job.h"
+
+G_BEGIN_DECLS
+
+GsPluginAction		 gs_plugin_job_get_action		(GsPluginJob	*self);
+GsAppListFilterFlags	 gs_plugin_job_get_dedupe_flags		(GsPluginJob	*self);
+GsPluginRefineFlags	 gs_plugin_job_get_refine_flags		(GsPluginJob	*self);
+gboolean		 gs_plugin_job_has_refine_flags		(GsPluginJob	*self,
+								 GsPluginRefineFlags refine_flags);
+void			 gs_plugin_job_add_refine_flags		(GsPluginJob	*self,
+								 GsPluginRefineFlags refine_flags);
+void			 gs_plugin_job_remove_refine_flags	(GsPluginJob	*self,
+								 GsPluginRefineFlags refine_flags);
+gboolean		 gs_plugin_job_get_interactive		(GsPluginJob	*self);
+gboolean		 gs_plugin_job_get_propagate_error	(GsPluginJob	*self);
+guint			 gs_plugin_job_get_max_results		(GsPluginJob	*self);
+GsAppListSortFunc	 gs_plugin_job_get_sort_func		(GsPluginJob	*self,
+								 gpointer	*user_data_out);
+const gchar		*gs_plugin_job_get_search		(GsPluginJob	*self);
+GsApp			*gs_plugin_job_get_app			(GsPluginJob	*self);
+GsAppList		*gs_plugin_job_get_list			(GsPluginJob	*self);
+GFile			*gs_plugin_job_get_file			(GsPluginJob	*self);
+GsPlugin		*gs_plugin_job_get_plugin		(GsPluginJob	*self);
+gchar			*gs_plugin_job_to_string		(GsPluginJob	*self);
+void			 gs_plugin_job_set_action		(GsPluginJob	*self,
+								 GsPluginAction	 action);
+
+G_END_DECLS
diff --git a/lib/gs-plugin-job-refine.c b/lib/gs-plugin-job-refine.c
new file mode 100644
index 0000000..f9618cd
--- /dev/null
+++ b/lib/gs-plugin-job-refine.c
@@ -0,0 +1,860 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-plugin-job-refine
+ * @short_description: A plugin job to refine #GsApps and add more data
+ *
+ * #GsPluginJobRefine is a #GsPluginJob representing a refine operation.
+ *
+ * It’s used to query and add more data to a set of #GsApps. The data to be set
+ * is controlled by the #GsPluginRefineFlags, and is looked up for all the apps
+ * in a #GsAppList by the loaded plugins.
+ *
+ * This class is a wrapper around #GsPluginClass.refine_async, calling it for
+ * all loaded plugins, with some additional refinements done on the results.
+ *
+ * In particular, if an app in the #GsAppList has %GS_APP_QUIRK_IS_WILDCARD,
+ * refining it will replace it with zero or more non-wildcard #GsApps in the
+ * #GsAppList, all of which are candidates for what the wildcard represents.
+ * For example, they may have the same ID as the wildcard, or match its name.
+ * Refining is the canonical process for resolving wildcards.
+ *
+ * This means that the #GsAppList at the end of the refine operation may not
+ * match the #GsAppList passed in as input. Retrieve the final #GsAppList using
+ * gs_plugin_job_refine_get_result_list(). The #GsAppList which was passed
+ * into the job will not be modified.
+ *
+ * Internally, the #GsPluginClass.refine_async() functions are called on all
+ * the plugins in series, and in series with a call to
+ * gs_odrs_provider_refine_async(). Once all of those calls are finished,
+ * zero or more recursive calls to run_refine_internal_async() are made in
+ * parallel to do a similar refine process on the addons, runtime and related
+ * components for all the components in the input #GsAppList. The refine job is
+ * complete once all these recursive calls complete.
+ *
+ * FIXME: Ideally, the #GsPluginClass.refine_async() calls would happen in
+ * parallel, but this cannot be the case until the results of the refine_async()
+ * call in one plugin don’t depend on the results of refine_async() in another.
+ * This still happens with several pairs of plugins.
+ *
+ * ```
+ *                                    run_async()
+ *                                         |
+ *                                         v
+ *           /-----------------------+-------------+----------------\
+ *           |                       |             |                |
+ * plugin->refine_async()            |             |                |
+ *           v             plugin->refine_async()  |                |
+ *           |                       v             …                |
+ *           |                       |             v  gs_odrs_provider_refine_async()
+ *           |                       |             |                v
+ *           |                       |             |                |
+ *           \-----------------------+-------------+----------------/
+ *                                         |
+ *                            finish_refine_internal_op()
+ *                                         |
+ *                                         v
+ *            /----------------------------+-----------------\
+ *            |                            |                 |
+ * run_refine_internal_async()  run_refine_internal_async()  …
+ *            |                            |                 |
+ *            v                            v                 v
+ *            \----------------------------+-----------------/
+ *                                         |
+ *                         finish_refine_internal_recursion()
+ * ```
+ *
+ * See also: #GsPluginClass.refine_async
+ * Since: 42
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <glib-object.h>
+#include <glib/gi18n.h>
+
+#include "gs-app.h"
+#include "gs-app-collation.h"
+#include "gs-app-private.h"
+#include "gs-app-list-private.h"
+#include "gs-enums.h"
+#include "gs-plugin-job-private.h"
+#include "gs-plugin-job-refine.h"
+#include "gs-utils.h"
+
+struct _GsPluginJobRefine
+{
+	GsPluginJob parent;
+
+	/* Input data. */
+	GsAppList *app_list;  /* (owned) */
+	GsPluginRefineFlags flags;
+
+	/* Output data. */
+	GsAppList *result_list;  /* (owned) (nullable) */
+};
+
+G_DEFINE_TYPE (GsPluginJobRefine, gs_plugin_job_refine, GS_TYPE_PLUGIN_JOB)
+
+typedef enum {
+	PROP_APP_LIST = 1,
+	PROP_FLAGS,
+} GsPluginJobRefineProperty;
+
+static GParamSpec *props[PROP_FLAGS + 1] = { NULL, };
+
+static void
+gs_plugin_job_refine_dispose (GObject *object)
+{
+	GsPluginJobRefine *self = GS_PLUGIN_JOB_REFINE (object);
+
+	g_clear_object (&self->app_list);
+	g_clear_object (&self->result_list);
+
+	G_OBJECT_CLASS (gs_plugin_job_refine_parent_class)->dispose (object);
+}
+
+static void
+gs_plugin_job_refine_constructed (GObject *object)
+{
+	GsPluginJobRefine *self = GS_PLUGIN_JOB_REFINE (object);
+
+	G_OBJECT_CLASS (gs_plugin_job_refine_parent_class)->constructed (object);
+
+	/* FIXME: the plugins should specify this, rather than hardcoding */
+	if (self->flags & (GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN_UI |
+			   GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN_HOSTNAME))
+		self->flags |= GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN;
+	if (self->flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_SIZE)
+		self->flags |= GS_PLUGIN_REFINE_FLAGS_REQUIRE_RUNTIME;
+}
+
+static void
+gs_plugin_job_refine_get_property (GObject    *object,
+                                   guint       prop_id,
+                                   GValue     *value,
+                                   GParamSpec *pspec)
+{
+	GsPluginJobRefine *self = GS_PLUGIN_JOB_REFINE (object);
+
+	switch ((GsPluginJobRefineProperty) prop_id) {
+	case PROP_APP_LIST:
+		g_value_set_object (value, self->app_list);
+		break;
+	case PROP_FLAGS:
+		g_value_set_flags (value, self->flags);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_plugin_job_refine_set_property (GObject      *object,
+                                   guint         prop_id,
+                                   const GValue *value,
+                                   GParamSpec   *pspec)
+{
+	GsPluginJobRefine *self = GS_PLUGIN_JOB_REFINE (object);
+
+	switch ((GsPluginJobRefineProperty) prop_id) {
+	case PROP_APP_LIST:
+		/* Construct only. */
+		g_assert (self->app_list == NULL);
+		self->app_list = g_value_dup_object (value);
+		g_object_notify_by_pspec (object, props[PROP_APP_LIST]);
+		break;
+	case PROP_FLAGS:
+		/* Construct only. */
+		g_assert (self->flags == 0);
+		self->flags = g_value_get_flags (value);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static gboolean
+app_is_valid_filter (GsApp    *app,
+                     gpointer  user_data)
+{
+	GsPluginJobRefine *self = GS_PLUGIN_JOB_REFINE (user_data);
+
+	return gs_plugin_loader_app_is_valid (app, self->flags);
+}
+
+static gint
+review_score_sort_cb (gconstpointer a, gconstpointer b)
+{
+	AsReview *ra = *((AsReview **) a);
+	AsReview *rb = *((AsReview **) b);
+	if (as_review_get_priority (ra) < as_review_get_priority (rb))
+		return 1;
+	if (as_review_get_priority (ra) > as_review_get_priority (rb))
+		return -1;
+	return 0;
+}
+
+static gboolean
+app_is_non_wildcard (GsApp *app, gpointer user_data)
+{
+	return !gs_app_has_quirk (app, GS_APP_QUIRK_IS_WILDCARD);
+}
+
+static void plugin_refine_cb (GObject      *source_object,
+                              GAsyncResult *result,
+                              gpointer      user_data);
+static void odrs_provider_refine_cb (GObject      *source_object,
+                                     GAsyncResult *result,
+                                     gpointer      user_data);
+static void finish_refine_internal_op (GTask  *task,
+                                       GError *error);
+static void recursive_internal_refine_cb (GObject      *source_object,
+                                          GAsyncResult *result,
+                                          gpointer      user_data);
+static void finish_refine_internal_recursion (GTask  *task,
+                                              GError *error);
+static gboolean run_refine_internal_finish (GsPluginJobRefine  *self,
+                                            GAsyncResult       *result,
+                                            GError            **error);
+
+typedef struct {
+	/* Input data. */
+	GsPluginLoader *plugin_loader;  /* (not nullable) (owned) */
+	GsAppList *list;  /* (not nullable) (owned) */
+	GsPluginRefineFlags flags;
+
+	/* In-progress data. */
+	guint n_pending_ops;
+	guint n_pending_recursions;
+	guint next_plugin_index;
+
+	/* Output data. */
+	GError *error;  /* (nullable) (owned) */
+} RefineInternalData;
+
+static void
+refine_internal_data_free (RefineInternalData *data)
+{
+	g_clear_object (&data->plugin_loader);
+	g_clear_object (&data->list);
+
+	g_assert (data->n_pending_ops == 0);
+	g_assert (data->n_pending_recursions == 0);
+
+	/* If an error occurred, it should have been stolen to pass to
+	 * g_task_return_error() by now. */
+	g_assert (data->error == NULL);
+
+	g_free (data);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (RefineInternalData, refine_internal_data_free)
+
+static void
+run_refine_internal_async (GsPluginJobRefine   *self,
+                           GsPluginLoader      *plugin_loader,
+                           GsAppList           *list,
+                           GsPluginRefineFlags  flags,
+                           GCancellable        *cancellable,
+                           GAsyncReadyCallback  callback,
+                           gpointer             user_data)
+{
+	GPtrArray *plugins;  /* (element-type GsPlugin) */
+	g_autoptr(GTask) task = NULL;
+	RefineInternalData *data;
+	g_autoptr(RefineInternalData) data_owned = NULL;
+
+	task = g_task_new (self, cancellable, callback, user_data);
+	g_task_set_source_tag (task, run_refine_internal_async);
+
+	data = data_owned = g_new0 (RefineInternalData, 1);
+	data->plugin_loader = g_object_ref (plugin_loader);
+	data->list = g_object_ref (list);
+	data->flags = flags;
+	g_task_set_task_data (task, g_steal_pointer (&data_owned), (GDestroyNotify) refine_internal_data_free);
+
+	/* try to adopt each application with a plugin */
+	gs_plugin_loader_run_adopt (plugin_loader, list);
+
+	data->n_pending_ops = 0;
+
+	/* run each plugin
+	 *
+	 * FIXME: For now, we have to run these vfuncs sequentially rather than
+	 * all in parallel. This is because there are still dependencies between
+	 * some of the plugins, where the code to refine an app in one plugin
+	 * depends on the results of refining it in another plugin first.
+	 *
+	 * Eventually, the plugins should all be changed/removed so that they
+	 * can operate independently. At that point, this code can be reverted
+	 * so that the refine_async() vfuncs are called in parallel. */
+	plugins = gs_plugin_loader_get_plugins (plugin_loader);
+
+	for (guint i = 0; i < plugins->len; i++) {
+		GsPlugin *plugin = g_ptr_array_index (plugins, i);
+		GsPluginClass *plugin_class = GS_PLUGIN_GET_CLASS (plugin);
+
+		if (!gs_plugin_get_enabled (plugin))
+			continue;
+		if (plugin_class->refine_async == NULL)
+			continue;
+
+		/* FIXME: The next refine_async() call is made in
+		 * finish_refine_internal_op(). */
+		data->next_plugin_index = i + 1;
+
+		/* run the batched plugin symbol */
+		data->n_pending_ops++;
+		plugin_class->refine_async (plugin, list, flags,
+					    cancellable, plugin_refine_cb, g_object_ref (task));
+
+		/* FIXME: The next refine_async() call is made in
+		 * finish_refine_internal_op(). */
+		return;
+	}
+
+	data->n_pending_ops++;
+	finish_refine_internal_op (task, NULL);
+}
+
+static void
+plugin_refine_cb (GObject      *source_object,
+                  GAsyncResult *result,
+                  gpointer      user_data)
+{
+	GsPlugin *plugin = GS_PLUGIN (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	GsPluginClass *plugin_class = GS_PLUGIN_GET_CLASS (plugin);
+	g_autoptr(GError) local_error = NULL;
+
+	if (!plugin_class->refine_finish (plugin, result, &local_error)) {
+		finish_refine_internal_op (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	gs_plugin_status_update (plugin, NULL, GS_PLUGIN_STATUS_FINISHED);
+
+	finish_refine_internal_op (task, NULL);
+}
+
+static void
+odrs_provider_refine_cb (GObject      *source_object,
+                         GAsyncResult *result,
+                         gpointer      user_data)
+{
+	GsOdrsProvider *odrs_provider = GS_ODRS_PROVIDER (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	g_autoptr(GError) local_error = NULL;
+
+	gs_odrs_provider_refine_finish (odrs_provider, result, &local_error);
+	finish_refine_internal_op (task, g_steal_pointer (&local_error));
+}
+
+/* @error is (transfer full) if non-NULL */
+static void
+finish_refine_internal_op (GTask  *task,
+                           GError *error)
+{
+	GsPluginJobRefine *self = g_task_get_source_object (task);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+	g_autoptr(GError) error_owned = g_steal_pointer (&error);
+	RefineInternalData *data = g_task_get_task_data (task);
+	GsPluginLoader *plugin_loader = data->plugin_loader;
+	GsAppList *list = data->list;
+	GsPluginRefineFlags flags = data->flags;
+	GsOdrsProvider *odrs_provider;
+	GsOdrsProviderRefineFlags odrs_refine_flags = 0;
+	GPtrArray *plugins;  /* (element-type GsPlugin) */
+
+	if (data->error == NULL && error_owned != NULL) {
+		data->error = g_steal_pointer (&error_owned);
+	} else if (error_owned != NULL) {
+		g_debug ("Additional error while refining: %s", error_owned->message);
+	}
+
+	g_assert (data->n_pending_ops > 0);
+	data->n_pending_ops--;
+
+	plugins = gs_plugin_loader_get_plugins (plugin_loader);
+
+	for (guint i = data->next_plugin_index; i < plugins->len; i++) {
+		GsPlugin *plugin = g_ptr_array_index (plugins, i);
+		GsPluginClass *plugin_class = GS_PLUGIN_GET_CLASS (plugin);
+
+		if (!gs_plugin_get_enabled (plugin))
+			continue;
+		if (plugin_class->refine_async == NULL)
+			continue;
+
+		/* FIXME: The next refine_async() call is made in
+		 * finish_refine_internal_op(). */
+		data->next_plugin_index = i + 1;
+
+		/* run the batched plugin symbol */
+		data->n_pending_ops++;
+		plugin_class->refine_async (plugin, list, flags,
+					    cancellable, plugin_refine_cb, g_object_ref (task));
+
+		/* FIXME: The next refine_async() call is made in
+		 * finish_refine_internal_op(). */
+		return;
+	}
+
+	if (data->next_plugin_index == plugins->len) {
+		/* Avoid the ODRS refine being run multiple times. */
+		data->next_plugin_index++;
+
+		/* Add ODRS data if needed */
+		odrs_provider = gs_plugin_loader_get_odrs_provider (plugin_loader);
+
+		if (flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_REVIEWS)
+			odrs_refine_flags |= GS_ODRS_PROVIDER_REFINE_FLAGS_GET_REVIEWS;
+		if (flags & (GS_PLUGIN_REFINE_FLAGS_REQUIRE_REVIEW_RATINGS |
+			     GS_PLUGIN_REFINE_FLAGS_REQUIRE_RATING))
+			odrs_refine_flags |= GS_ODRS_PROVIDER_REFINE_FLAGS_GET_RATINGS;
+
+		if (odrs_provider != NULL && odrs_refine_flags != 0) {
+			data->n_pending_ops++;
+			gs_odrs_provider_refine_async (odrs_provider, list, odrs_refine_flags,
+						       cancellable, odrs_provider_refine_cb, g_object_ref (task));
+		}
+	}
+
+	if (data->n_pending_ops > 0)
+		return;
+
+	/* At this point, all the plugin->refine() calls are complete and the
+	 * gs_odrs_provider_refine_async() call is also complete. If an error
+	 * occurred during those calls, return with it now rather than
+	 * proceeding to the recursive calls below. */
+	if (data->error != NULL) {
+		g_task_return_error (task, g_steal_pointer (&data->error));
+		return;
+	}
+
+	/* filter any wildcard apps left in the list */
+	gs_app_list_filter (list, app_is_non_wildcard, NULL);
+
+	/* ensure these are sorted by score */
+	if (flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_REVIEWS) {
+		GPtrArray *reviews;
+		for (guint i = 0; i < gs_app_list_length (list); i++) {
+			GsApp *app = gs_app_list_index (list, i);
+			reviews = gs_app_get_reviews (app);
+			g_ptr_array_sort (reviews, review_score_sort_cb);
+		}
+	}
+
+	/* Now run several recursive calls to run_refine_internal_async() in
+	 * parallel, to refine related components. */
+	data->n_pending_recursions = 1;
+
+	/* refine addons one layer deep */
+	if (flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_ADDONS) {
+		g_autoptr(GsAppList) addons_list = gs_app_list_new ();
+		GsPluginRefineFlags addons_flags = flags;
+
+		addons_flags &= ~(GS_PLUGIN_REFINE_FLAGS_REQUIRE_ADDONS |
+				  GS_PLUGIN_REFINE_FLAGS_REQUIRE_REVIEWS |
+				  GS_PLUGIN_REFINE_FLAGS_REQUIRE_REVIEW_RATINGS);
+
+		for (guint i = 0; i < gs_app_list_length (list); i++) {
+			GsApp *app = gs_app_list_index (list, i);
+			g_autoptr(GsAppList) addons = gs_app_dup_addons (app);
+
+			for (guint j = 0; addons != NULL && j < gs_app_list_length (addons); j++) {
+				GsApp *addon = gs_app_list_index (addons, j);
+				g_debug ("refining app %s addon %s",
+					 gs_app_get_id (app),
+					 gs_app_get_id (addon));
+				gs_app_list_add (addons_list, addon);
+			}
+		}
+
+		if (gs_app_list_length (addons_list) > 0 && addons_flags != 0) {
+			data->n_pending_recursions++;
+			run_refine_internal_async (self, plugin_loader,
+						   addons_list, addons_flags,
+						   cancellable, recursive_internal_refine_cb,
+						   g_object_ref (task));
+		}
+	}
+
+	/* also do runtime */
+	if (flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_RUNTIME) {
+		g_autoptr(GsAppList) runtimes_list = gs_app_list_new ();
+		GsPluginRefineFlags runtimes_flags = flags;
+
+		runtimes_flags &= ~GS_PLUGIN_REFINE_FLAGS_REQUIRE_RUNTIME;
+
+		for (guint i = 0; i < gs_app_list_length (list); i++) {
+			GsApp *app = gs_app_list_index (list, i);
+			GsApp *runtime = gs_app_get_runtime (app);
+
+			if (runtime != NULL)
+				gs_app_list_add (runtimes_list, runtime);
+		}
+
+		if (gs_app_list_length (runtimes_list) > 0 && runtimes_flags != 0) {
+			data->n_pending_recursions++;
+			run_refine_internal_async (self, plugin_loader,
+						   runtimes_list, runtimes_flags,
+						   cancellable, recursive_internal_refine_cb,
+						   g_object_ref (task));
+		}
+	}
+
+	/* also do related packages one layer deep */
+	if (flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_RELATED) {
+		g_autoptr(GsAppList) related_list = gs_app_list_new ();
+		GsPluginRefineFlags related_flags = flags;
+
+		related_flags &= ~GS_PLUGIN_REFINE_FLAGS_REQUIRE_RELATED;
+
+		for (guint i = 0; i < gs_app_list_length (list); i++) {
+			GsApp *app = gs_app_list_index (list, i);
+			GsAppList *related = gs_app_get_related (app);
+			for (guint j = 0; j < gs_app_list_length (related); j++) {
+				GsApp *app2 = gs_app_list_index (related, j);
+				g_debug ("refining related: %s[%s]",
+					 gs_app_get_id (app2),
+					 gs_app_get_source_default (app2));
+				gs_app_list_add (related_list, app2);
+			}
+		}
+
+		if (gs_app_list_length (related_list) > 0 && related_flags != 0) {
+			data->n_pending_recursions++;
+			run_refine_internal_async (self, plugin_loader,
+						   related_list, related_flags,
+						   cancellable, recursive_internal_refine_cb,
+						   g_object_ref (task));
+		}
+	}
+
+	finish_refine_internal_recursion (task, NULL);
+}
+
+static void
+recursive_internal_refine_cb (GObject      *source_object,
+                              GAsyncResult *result,
+                              gpointer      user_data)
+{
+	GsPluginJobRefine *self = GS_PLUGIN_JOB_REFINE (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	g_autoptr(GError) local_error = NULL;
+
+	run_refine_internal_finish (self, result, &local_error);
+	finish_refine_internal_recursion (task, g_steal_pointer (&local_error));
+}
+
+/* @error is (transfer full) if non-NULL */
+static void
+finish_refine_internal_recursion (GTask  *task,
+                                  GError *error)
+{
+	g_autoptr(GError) error_owned = g_steal_pointer (&error);
+	RefineInternalData *data = g_task_get_task_data (task);
+
+	if (data->error == NULL && error_owned != NULL) {
+		data->error = g_steal_pointer (&error_owned);
+	} else if (error_owned != NULL) {
+		g_debug ("Additional error while refining: %s", error_owned->message);
+	}
+
+	g_assert (data->n_pending_recursions > 0);
+	data->n_pending_recursions--;
+
+	if (data->n_pending_recursions > 0)
+		return;
+
+	/* The entire refine operation (and all its sub-operations and
+	 * recursions) is complete. */
+	if (data->error != NULL)
+		g_task_return_error (task, g_steal_pointer (&data->error));
+	else
+		g_task_return_boolean (task, TRUE);
+}
+
+static gboolean
+run_refine_internal_finish (GsPluginJobRefine  *self,
+                            GAsyncResult       *result,
+                            GError            **error)
+{
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+static gboolean
+app_thaw_notify_idle (gpointer data)
+{
+	GsApp *app = GS_APP (data);
+	g_object_thaw_notify (G_OBJECT (app));
+	g_object_unref (app);
+	return G_SOURCE_REMOVE;
+}
+
+static void run_cb (GObject      *source_object,
+                    GAsyncResult *result,
+                    gpointer      user_data);
+static void finish_run (GTask     *task,
+                        GsAppList *result_list);
+
+static void
+gs_plugin_job_refine_run_async (GsPluginJob         *job,
+                                GsPluginLoader      *plugin_loader,
+                                GCancellable        *cancellable,
+                                GAsyncReadyCallback  callback,
+                                gpointer             user_data)
+{
+	GsPluginJobRefine *self = GS_PLUGIN_JOB_REFINE (job);
+	g_autoptr(GTask) task = NULL;
+	g_autoptr(GsAppList) result_list = NULL;
+
+	/* check required args */
+	task = g_task_new (job, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_plugin_job_refine_run_async);
+
+	/* Operate on a copy of the input list so we don’t modify it when
+	 * resolving wildcards. */
+	result_list = gs_app_list_copy (self->app_list);
+	g_task_set_task_data (task, g_object_ref (result_list), (GDestroyNotify) g_object_unref);
+
+	/* nothing to do */
+	if (self->flags == 0 ||
+	    gs_app_list_length (result_list) == 0) {
+		g_debug ("no refine flags set for transaction or app list is empty");
+		finish_run (task, result_list);
+		return;
+	}
+
+	/* freeze all apps */
+	for (guint i = 0; i < gs_app_list_length (self->app_list); i++) {
+		GsApp *app = gs_app_list_index (self->app_list, i);
+		g_object_freeze_notify (G_OBJECT (app));
+	}
+
+	/* Start refining the apps. */
+	run_refine_internal_async (self, plugin_loader, result_list,
+				   self->flags, cancellable,
+				   run_cb, g_steal_pointer (&task));
+}
+
+static void
+run_cb (GObject      *source_object,
+        GAsyncResult *result,
+        gpointer      user_data)
+{
+	GsPluginJobRefine *self = GS_PLUGIN_JOB_REFINE (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	GsAppList *result_list = g_task_get_task_data (task);
+	g_autoptr(GError) local_error = NULL;
+
+	if (run_refine_internal_finish (self, result, &local_error)) {
+		/* remove any addons that have the same source as the parent app */
+		for (guint i = 0; i < gs_app_list_length (result_list); i++) {
+			g_autoptr(GPtrArray) to_remove = g_ptr_array_new ();
+			GsApp *app = gs_app_list_index (result_list, i);
+			g_autoptr(GsAppList) addons = gs_app_dup_addons (app);
+
+			/* find any apps with the same source */
+			const gchar *pkgname_parent = gs_app_get_source_default (app);
+			if (pkgname_parent == NULL)
+				continue;
+			for (guint j = 0; addons != NULL && j < gs_app_list_length (addons); j++) {
+				GsApp *addon = gs_app_list_index (addons, j);
+				if (g_strcmp0 (gs_app_get_source_default (addon),
+					       pkgname_parent) == 0) {
+					g_debug ("%s has the same pkgname of %s as %s",
+						 gs_app_get_unique_id (app),
+						 pkgname_parent,
+						 gs_app_get_unique_id (addon));
+					g_ptr_array_add (to_remove, addon);
+				}
+			}
+
+			/* remove any addons with the same source */
+			for (guint j = 0; j < to_remove->len; j++) {
+				GsApp *addon = g_ptr_array_index (to_remove, j);
+				gs_app_remove_addon (app, addon);
+			}
+		}
+	}
+
+	/* now emit all the changed signals */
+	for (guint i = 0; i < gs_app_list_length (self->app_list); i++) {
+		GsApp *app = gs_app_list_index (self->app_list, i);
+		g_idle_add (app_thaw_notify_idle, g_object_ref (app));
+	}
+
+	/* Delayed error handling. */
+	if (local_error != NULL) {
+		gs_utils_error_convert_gio (&local_error);
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	finish_run (task, result_list);
+}
+
+static void
+finish_run (GTask     *task,
+            GsAppList *result_list)
+{
+	GsPluginJobRefine *self = g_task_get_source_object (task);
+	g_autofree gchar *job_debug = NULL;
+
+	/* Internal calls to #GsPluginJobRefine may want to do their own
+	 * filtering, typically if the refine is being done as part of another
+	 * plugin job. If so, only filter to remove wildcards. Wildcards should
+	 * always be removed, as they should have been resolved as part of the
+	 * refine; any remaining wildcards will never be resolved.
+	 *
+	 * If the flag is not specified, filter by a variety of indicators of
+	 * what a ‘valid’ app is. */
+	if (self->flags & GS_PLUGIN_REFINE_FLAGS_DISABLE_FILTERING)
+		gs_app_list_filter (result_list, app_is_non_wildcard, NULL);
+	else
+		gs_app_list_filter (result_list, app_is_valid_filter, self);
+
+	/* show elapsed time */
+	job_debug = gs_plugin_job_to_string (GS_PLUGIN_JOB (self));
+	g_debug ("%s", job_debug);
+
+	/* success */
+	g_set_object (&self->result_list, result_list);
+	g_task_return_boolean (task, TRUE);
+}
+
+static gboolean
+gs_plugin_job_refine_run_finish (GsPluginJob   *self,
+                                 GAsyncResult  *result,
+                                 GError       **error)
+{
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+static void
+gs_plugin_job_refine_class_init (GsPluginJobRefineClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+	GsPluginJobClass *job_class = GS_PLUGIN_JOB_CLASS (klass);
+
+	object_class->dispose = gs_plugin_job_refine_dispose;
+	object_class->constructed = gs_plugin_job_refine_constructed;
+	object_class->get_property = gs_plugin_job_refine_get_property;
+	object_class->set_property = gs_plugin_job_refine_set_property;
+
+	job_class->run_async = gs_plugin_job_refine_run_async;
+	job_class->run_finish = gs_plugin_job_refine_run_finish;
+
+	/**
+	 * GsPluginJobRefine:app-list:
+	 *
+	 * List of #GsApps to refine.
+	 *
+	 * This will not change during the course of the operation.
+	 *
+	 * Since: 42
+	 */
+	props[PROP_APP_LIST] =
+		g_param_spec_object ("app-list", "App List",
+				     "List of GsApps to refine.",
+				     GS_TYPE_APP_LIST,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				     G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPluginJobRefine:flags:
+	 *
+	 * Flags to control what to refine.
+	 *
+	 * Since: 42
+	 */
+	props[PROP_FLAGS] =
+		g_param_spec_flags ("flags", "Flags",
+				    "Flags to control what to refine.",
+				     GS_TYPE_PLUGIN_REFINE_FLAGS, GS_PLUGIN_REFINE_FLAGS_NONE,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				     G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	g_object_class_install_properties (object_class, G_N_ELEMENTS (props), props);
+}
+
+static void
+gs_plugin_job_refine_init (GsPluginJobRefine *self)
+{
+}
+
+/**
+ * gs_plugin_job_refine_new:
+ * @app_list: the list of #GsApps to refine
+ * @flags: flags to affect what is refined
+ *
+ * Create a new #GsPluginJobRefine for refining the given @app_list.
+ *
+ * Returns: (transfer full): a new #GsPluginJobRefine
+ * Since: 42
+ */
+GsPluginJob *
+gs_plugin_job_refine_new (GsAppList           *app_list,
+                          GsPluginRefineFlags  flags)
+{
+	return g_object_new (GS_TYPE_PLUGIN_JOB_REFINE,
+			     "app-list", app_list,
+			     "flags", flags,
+			     NULL);
+}
+
+/**
+ * gs_plugin_job_refine_new_for_app:
+ * @app: the #GsApp to refine
+ * @flags: flags to affect what is refined
+ *
+ * Create a new #GsPluginJobRefine for refining the given @app.
+ *
+ * Returns: (transfer full): a new #GsPluginJobRefine
+ * Since: 42
+ */
+GsPluginJob *
+gs_plugin_job_refine_new_for_app (GsApp               *app,
+                                  GsPluginRefineFlags  flags)
+{
+	g_autoptr(GsAppList) list = gs_app_list_new ();
+	gs_app_list_add (list, app);
+
+	return gs_plugin_job_refine_new (list, flags);
+}
+
+/**
+ * gs_plugin_job_refine_get_result_list:
+ * @self: a #GsPluginJobRefine
+ *
+ * Get the full list of refined #GsApps. This includes apps created in place of
+ * wildcards, if wildcards were provided in the #GsAppList passed to
+ * gs_plugin_job_refine_new().
+ *
+ * If this is called before the job is complete, %NULL will be returned.
+ *
+ * Returns: (transfer none) (nullable): the job results, or %NULL on error
+ *   or if called before the job has completed
+ * Since: 42
+ */
+GsAppList *
+gs_plugin_job_refine_get_result_list (GsPluginJobRefine *self)
+{
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB_REFINE (self), NULL);
+
+	return self->result_list;
+}
diff --git a/lib/gs-plugin-job-refine.h b/lib/gs-plugin-job-refine.h
new file mode 100644
index 0000000..ed207bc
--- /dev/null
+++ b/lib/gs-plugin-job-refine.h
@@ -0,0 +1,31 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <glib-object.h>
+
+#include "gs-plugin-job.h"
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_PLUGIN_JOB_REFINE (gs_plugin_job_refine_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsPluginJobRefine, gs_plugin_job_refine, GS, PLUGIN_JOB_REFINE, GsPluginJob)
+
+GsPluginJob	*gs_plugin_job_refine_new_for_app	(GsApp               *app,
+							 GsPluginRefineFlags  flags);
+GsPluginJob	*gs_plugin_job_refine_new		(GsAppList           *app_list,
+							 GsPluginRefineFlags  flags);
+
+GsAppList	*gs_plugin_job_refine_get_result_list	(GsPluginJobRefine   *self);
+
+G_END_DECLS
diff --git a/lib/gs-plugin-job-refresh-metadata.c b/lib/gs-plugin-job-refresh-metadata.c
new file mode 100644
index 0000000..01c65d1
--- /dev/null
+++ b/lib/gs-plugin-job-refresh-metadata.c
@@ -0,0 +1,531 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2022 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-plugin-job-refresh-metadata
+ * @short_description: A plugin job to refresh metadata
+ *
+ * #GsPluginJobRefreshMetadata is a #GsPluginJob representing an operation to
+ * refresh metadata inside plugins and about applications.
+ *
+ * For example, the metadata could be the list of applications available, or
+ * the list of updates, or a new set of popular applications to highlight.
+ *
+ * The maximum cache age should be set using
+ * #GsPluginJobRefreshMetadata:cache-age-secs. If this is not a low value, this
+ * job is not expected to do much work. Set it to zero to force all caches to be
+ * refreshed.
+ *
+ * This class is a wrapper around #GsPluginClass.refresh_metadata_async(),
+ * calling it for all loaded plugins. In addition it will refresh ODRS data on
+ * the #GsOdrsProvider set on the #GsPluginLoader.
+ *
+ * Once the refresh is complete, signals may be asynchronously emitted on
+ * plugins, apps and the #GsPluginLoader to indicate what metadata or sets of
+ * apps have changed.
+ *
+ * See also: #GsPluginClass.refresh_metadata_async
+ * Since: 42
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <glib-object.h>
+#include <glib/gi18n.h>
+
+#include "gs-enums.h"
+#include "gs-external-appstream-utils.h"
+#include "gs-plugin-job-private.h"
+#include "gs-plugin-job-refresh-metadata.h"
+#include "gs-plugin-types.h"
+#include "gs-odrs-provider.h"
+#include "gs-utils.h"
+
+/* A tuple to store the last-received progress data for a single download.
+ * See progress_cb() for more details. */
+typedef struct {
+	gsize bytes_downloaded;
+	gsize total_download_size;
+} ProgressTuple;
+
+struct _GsPluginJobRefreshMetadata
+{
+	GsPluginJob parent;
+
+	/* Input arguments. */
+	guint64 cache_age_secs;
+	GsPluginRefreshMetadataFlags flags;
+
+	/* In-progress data. */
+	GError *saved_error;  /* (owned) (nullable) */
+	guint n_pending_ops;
+#ifdef ENABLE_EXTERNAL_APPSTREAM
+	ProgressTuple external_appstream_progress;
+#endif
+	ProgressTuple odrs_progress;
+	struct {
+		guint n_plugins;
+		guint n_plugins_complete;
+	} plugins_progress;
+	GSource *progress_source;  /* (owned) (nullable) */
+};
+
+G_DEFINE_TYPE (GsPluginJobRefreshMetadata, gs_plugin_job_refresh_metadata, GS_TYPE_PLUGIN_JOB)
+
+typedef enum {
+	PROP_CACHE_AGE_SECS = 1,
+	PROP_FLAGS,
+} GsPluginJobRefreshMetadataProperty;
+
+static GParamSpec *props[PROP_FLAGS + 1] = { NULL, };
+
+typedef enum {
+	SIGNAL_PROGRESS,
+} GsPluginJobRefreshMetadataSignal;
+
+static guint signals[SIGNAL_PROGRESS + 1] = { 0, };
+
+static void
+gs_plugin_job_refresh_metadata_dispose (GObject *object)
+{
+	GsPluginJobRefreshMetadata *self = GS_PLUGIN_JOB_REFRESH_METADATA (object);
+
+	g_assert (self->saved_error == NULL);
+	g_assert (self->n_pending_ops == 0);
+
+	/* Progress reporting should have been stopped by now. */
+	if (self->progress_source != NULL) {
+		g_assert (g_source_is_destroyed (self->progress_source));
+		g_clear_pointer (&self->progress_source, g_source_unref);
+	}
+
+	G_OBJECT_CLASS (gs_plugin_job_refresh_metadata_parent_class)->dispose (object);
+}
+
+static void
+gs_plugin_job_refresh_metadata_get_property (GObject    *object,
+                                             guint       prop_id,
+                                             GValue     *value,
+                                             GParamSpec *pspec)
+{
+	GsPluginJobRefreshMetadata *self = GS_PLUGIN_JOB_REFRESH_METADATA (object);
+
+	switch ((GsPluginJobRefreshMetadataProperty) prop_id) {
+	case PROP_CACHE_AGE_SECS:
+		g_value_set_uint64 (value, self->cache_age_secs);
+		break;
+	case PROP_FLAGS:
+		g_value_set_flags (value, self->flags);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_plugin_job_refresh_metadata_set_property (GObject      *object,
+                                             guint         prop_id,
+                                             const GValue *value,
+                                             GParamSpec   *pspec)
+{
+	GsPluginJobRefreshMetadata *self = GS_PLUGIN_JOB_REFRESH_METADATA (object);
+
+	switch ((GsPluginJobRefreshMetadataProperty) prop_id) {
+	case PROP_CACHE_AGE_SECS:
+		/* Construct only. */
+		g_assert (self->cache_age_secs == 0);
+		self->cache_age_secs = g_value_get_uint64 (value);
+		g_object_notify_by_pspec (object, props[prop_id]);
+		break;
+	case PROP_FLAGS:
+		/* Construct only. */
+		g_assert (self->flags == 0);
+		self->flags = g_value_get_flags (value);
+		g_object_notify_by_pspec (object, props[prop_id]);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void refresh_progress_tuple_cb (gsize    bytes_downloaded,
+                                       gsize    total_download_size,
+                                       gpointer user_data);
+static gboolean progress_cb (gpointer user_data);
+#ifdef ENABLE_EXTERNAL_APPSTREAM
+static void external_appstream_refresh_cb (GObject      *source_object,
+                                           GAsyncResult *result,
+                                           gpointer      user_data);
+#endif
+static void odrs_provider_refresh_ratings_cb (GObject      *source_object,
+                                              GAsyncResult *result,
+                                              gpointer      user_data);
+static void plugin_refresh_metadata_cb (GObject      *source_object,
+                                        GAsyncResult *result,
+                                        gpointer      user_data);
+static void finish_op (GTask  *task,
+                       GError *error);
+
+static void
+gs_plugin_job_refresh_metadata_run_async (GsPluginJob         *job,
+                                          GsPluginLoader      *plugin_loader,
+                                          GCancellable        *cancellable,
+                                          GAsyncReadyCallback  callback,
+                                          gpointer             user_data)
+{
+	GsPluginJobRefreshMetadata *self = GS_PLUGIN_JOB_REFRESH_METADATA (job);
+	g_autoptr(GTask) task = NULL;
+	GPtrArray *plugins;  /* (element-type GsPlugin) */
+	gboolean any_plugins_ran = FALSE;
+	GsOdrsProvider *odrs_provider;
+
+	/* Chosen to allow a few UI updates per second without updating the
+	 * progress label so often it’s unreadable. */
+	const guint progress_update_period_ms = 300;
+
+	/* check required args */
+	task = g_task_new (job, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_plugin_job_refresh_metadata_run_async);
+	g_task_set_task_data (task, g_object_ref (plugin_loader), (GDestroyNotify) g_object_unref);
+
+	/* Set up the progress timeout. This periodically sums up the progress
+	 * tuples in `self->*_progress` and reports them to the calling
+	 * function via the #GsPluginJobRefreshMetadata::progress signal, giving
+	 * an overall progress for all the parallel operations. */
+	self->progress_source = g_timeout_source_new (progress_update_period_ms);
+	g_source_set_callback (self->progress_source, progress_cb, g_object_ref (self), g_object_unref);
+	g_source_attach (self->progress_source, g_main_context_get_thread_default ());
+
+	/* run each plugin, keeping a counter of pending operations which is
+	 * initialised to 1 until all the operations are started */
+	self->n_pending_ops = 1;
+	plugins = gs_plugin_loader_get_plugins (plugin_loader);
+	odrs_provider = gs_plugin_loader_get_odrs_provider (plugin_loader);
+
+	/* Start downloading updated external appstream before anything else */
+#ifdef ENABLE_EXTERNAL_APPSTREAM
+	self->n_pending_ops++;
+	gs_external_appstream_refresh_async (self->cache_age_secs,
+					     refresh_progress_tuple_cb,
+					     &self->external_appstream_progress,
+					     cancellable,
+					     external_appstream_refresh_cb,
+					     g_object_ref (task));
+#endif
+
+	for (guint i = 0; i < plugins->len; i++) {
+		GsPlugin *plugin = g_ptr_array_index (plugins, i);
+		GsPluginClass *plugin_class = GS_PLUGIN_GET_CLASS (plugin);
+
+		if (!gs_plugin_get_enabled (plugin))
+			continue;
+		if (plugin_class->refresh_metadata_async == NULL)
+			continue;
+
+		/* at least one plugin supports this vfunc */
+		any_plugins_ran = TRUE;
+
+		/* Set up progress reporting for this plugin. */
+		self->plugins_progress.n_plugins++;
+
+		/* run the plugin */
+		self->n_pending_ops++;
+		plugin_class->refresh_metadata_async (plugin,
+						      self->cache_age_secs,
+						      self->flags,
+						      cancellable,
+						      plugin_refresh_metadata_cb,
+						      g_object_ref (task));
+	}
+
+	if (odrs_provider != NULL) {
+		self->n_pending_ops++;
+		gs_odrs_provider_refresh_ratings_async (odrs_provider,
+							self->cache_age_secs,
+							refresh_progress_tuple_cb,
+							&self->odrs_progress,
+							cancellable,
+							odrs_provider_refresh_ratings_cb,
+							g_object_ref (task));
+	}
+
+	/* some functions are really required for proper operation */
+	if (!any_plugins_ran) {
+		g_autoptr(GError) local_error = NULL;
+		g_set_error_literal (&local_error,
+				     GS_PLUGIN_ERROR,
+				     GS_PLUGIN_ERROR_NOT_SUPPORTED,
+				     "no plugin could handle refreshing");
+		finish_op (task, g_steal_pointer (&local_error));
+	} else {
+		finish_op (task, NULL);
+	}
+}
+
+static void
+refresh_progress_tuple_cb (gsize    bytes_downloaded,
+                           gsize    total_download_size,
+                           gpointer user_data)
+{
+	ProgressTuple *tuple = user_data;
+
+	tuple->bytes_downloaded = bytes_downloaded;
+	tuple->total_download_size = total_download_size;
+
+	/* The timeout callback in progress_cb() periodically sums these. No
+	 * need to notify of progress from here. */
+}
+
+static gboolean
+progress_cb (gpointer user_data)
+{
+	GsPluginJobRefreshMetadata *self = GS_PLUGIN_JOB_REFRESH_METADATA (user_data);
+#ifdef ENABLE_EXTERNAL_APPSTREAM
+	gdouble external_appstream_completion = 0.0;
+#endif
+	gdouble odrs_completion = 0.0;
+	gdouble progress;
+	guint n_portions;
+
+	/* Sum up the progress for all parallel operations. This is complicated
+	 * by the fact that external-appstream and ODRS operations report their
+	 * progress in terms of bytes downloaded, but the other operations are
+	 * just a counter.
+	 *
+	 * There is further complication from the fact that external-appstream
+	 * support can be compiled out.
+	 *
+	 * Allocate each operation an equal portion of 100 percentage points. In
+	 * this context, an operation is either a call to a plugin’s
+	 * refresh_metadata_async() vfunc, or an external-appstream or ODRS
+	 * refresh. */
+	n_portions = self->plugins_progress.n_plugins;
+
+#ifdef ENABLE_EXTERNAL_APPSTREAM
+	if (self->external_appstream_progress.total_download_size > 0)
+		external_appstream_completion = (self->external_appstream_progress.bytes_downloaded /
+						 self->external_appstream_progress.total_download_size);
+	n_portions++;
+#endif
+
+	if (self->odrs_progress.total_download_size > 0)
+		odrs_completion = (self->odrs_progress.bytes_downloaded /
+				   self->odrs_progress.total_download_size);
+	n_portions++;
+
+	/* Report progress via signal emission. */
+	progress = (100.0 / n_portions) * (self->plugins_progress.n_plugins_complete + odrs_completion);
+#ifdef ENABLE_EXTERNAL_APPSTREAM
+	progress += (100.0 / n_portions) * external_appstream_completion;
+#endif
+
+	g_signal_emit (self, signals[SIGNAL_PROGRESS], 0, (guint) progress);
+
+	return G_SOURCE_CONTINUE;
+}
+
+#ifdef ENABLE_EXTERNAL_APPSTREAM
+static void
+external_appstream_refresh_cb (GObject      *source_object,
+                               GAsyncResult *result,
+                               gpointer      user_data)
+{
+	g_autoptr(GTask) task = G_TASK (user_data);
+	g_autoptr(GError) local_error = NULL;
+
+	if (!gs_external_appstream_refresh_finish (result, &local_error))
+		g_debug ("Failed to refresh external appstream: %s", local_error->message);
+	/* Intentionally ignore errors, to not block other plugins */
+	finish_op (task, NULL);
+}
+#endif  /* ENABLE_EXTERNAL_APPSTREAM */
+
+static void
+odrs_provider_refresh_ratings_cb (GObject      *source_object,
+                                  GAsyncResult *result,
+                                  gpointer      user_data)
+{
+	GsOdrsProvider *odrs_provider = GS_ODRS_PROVIDER (source_object);
+	g_autoptr(GTask) task = G_TASK (user_data);
+	g_autoptr(GError) local_error = NULL;
+
+	if (!gs_odrs_provider_refresh_ratings_finish (odrs_provider, result, &local_error))
+		g_debug ("Failed to refresh ratings: %s", local_error->message);
+	/* Intentionally ignore errors, to not block other plugins */
+	finish_op (task, NULL);
+}
+
+static void
+plugin_refresh_metadata_cb (GObject      *source_object,
+                            GAsyncResult *result,
+                            gpointer      user_data)
+{
+	GsPlugin *plugin = GS_PLUGIN (source_object);
+	GsPluginClass *plugin_class = GS_PLUGIN_GET_CLASS (plugin);
+	g_autoptr(GTask) task = G_TASK (user_data);
+	GsPluginJobRefreshMetadata *self = g_task_get_source_object (task);
+	g_autoptr(GError) local_error = NULL;
+
+	if (!plugin_class->refresh_metadata_finish (plugin, result, &local_error))
+		g_debug ("Failed to refresh plugin '%s': %s", gs_plugin_get_name (plugin), local_error->message);
+	gs_plugin_status_update (plugin, NULL, GS_PLUGIN_STATUS_FINISHED);
+
+	/* Update progress reporting. */
+	self->plugins_progress.n_plugins_complete++;
+
+	/* Intentionally ignore errors, to not block other plugins */
+	finish_op (task, NULL);
+}
+
+/* @error is (transfer full) if non-%NULL */
+static void
+finish_op (GTask  *task,
+           GError *error)
+{
+	GsPluginJobRefreshMetadata *self = g_task_get_source_object (task);
+	g_autoptr(GError) error_owned = g_steal_pointer (&error);
+	g_autofree gchar *job_debug = NULL;
+
+	if (error_owned != NULL && self->saved_error == NULL)
+		self->saved_error = g_steal_pointer (&error_owned);
+	else if (error_owned != NULL)
+		g_debug ("Additional error while refreshing metadata: %s", error_owned->message);
+
+	g_assert (self->n_pending_ops > 0);
+	self->n_pending_ops--;
+
+	if (self->n_pending_ops > 0)
+		return;
+
+	/* Emit one final progress update, then stop any further ones.
+	 * Ensure the emission is in the right #GMainContext. */
+	g_assert (g_main_context_is_owner (g_task_get_context (task)));
+	progress_cb (self);
+	g_source_destroy (self->progress_source);
+
+	/* Get the results of the parallel ops. */
+	if (self->saved_error != NULL) {
+		g_task_return_error (task, g_steal_pointer (&self->saved_error));
+		return;
+	}
+
+	/* show elapsed time */
+	job_debug = gs_plugin_job_to_string (GS_PLUGIN_JOB (self));
+	g_debug ("%s", job_debug);
+
+	/* Check the intermediate working values are all cleared. */
+	g_assert (self->saved_error == NULL);
+	g_assert (self->n_pending_ops == 0);
+
+	/* success */
+	g_task_return_boolean (task, TRUE);
+}
+
+static gboolean
+gs_plugin_job_refresh_metadata_run_finish (GsPluginJob   *self,
+                                           GAsyncResult  *result,
+                                           GError       **error)
+{
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+static void
+gs_plugin_job_refresh_metadata_class_init (GsPluginJobRefreshMetadataClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+	GsPluginJobClass *job_class = GS_PLUGIN_JOB_CLASS (klass);
+
+	object_class->dispose = gs_plugin_job_refresh_metadata_dispose;
+	object_class->get_property = gs_plugin_job_refresh_metadata_get_property;
+	object_class->set_property = gs_plugin_job_refresh_metadata_set_property;
+
+	job_class->run_async = gs_plugin_job_refresh_metadata_run_async;
+	job_class->run_finish = gs_plugin_job_refresh_metadata_run_finish;
+
+	/**
+	 * GsPluginJobRefreshMetadata:cache-age-secs:
+	 *
+	 * Maximum age of caches before they are refreshed.
+	 *
+	 * Since: 42
+	 */
+	props[PROP_CACHE_AGE_SECS] =
+		g_param_spec_uint64 ("cache-age-secs", "Cache Age",
+				     "Maximum age of caches before they are refreshed.",
+				     0, G_MAXUINT64, 0,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				     G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPluginJobRefreshMetadata:flags:
+	 *
+	 * Flags to specify how the refresh job should behave.
+	 *
+	 * Since: 42
+	 */
+	props[PROP_FLAGS] =
+		g_param_spec_flags ("flags", "Flags",
+				    "Flags to specify how the refresh job should behave.",
+				    GS_TYPE_PLUGIN_REFRESH_METADATA_FLAGS, GS_PLUGIN_REFRESH_METADATA_FLAGS_NONE,
+				    G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+				    G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	g_object_class_install_properties (object_class, G_N_ELEMENTS (props), props);
+
+	/**
+	 * GsPluginJobRefreshMetadata::progress:
+	 * @progress_percent: percentage completion of the job, [0, 100], or
+	 *   %G_MAXUINT to indicate that progress is unknown
+	 *
+	 * Emitted during #GsPluginJob.run_async() when progress is made.
+	 *
+	 * It’s emitted in the thread which is running the #GMainContext which
+	 * was the thread-default context when #GsPluginJob.run_async() was
+	 * called.
+	 *
+	 * Since: 42
+	 */
+	signals[SIGNAL_PROGRESS] =
+		g_signal_new ("progress",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      0, NULL, NULL, g_cclosure_marshal_VOID__UINT,
+			      G_TYPE_NONE, 1, G_TYPE_UINT);
+}
+
+static void
+gs_plugin_job_refresh_metadata_init (GsPluginJobRefreshMetadata *self)
+{
+}
+
+/**
+ * gs_plugin_job_refresh_metadata_new:
+ * @cache_age_secs: maximum allowed cache age, in seconds
+ * @flags: flags to affect the refresh
+ *
+ * Create a new #GsPluginJobRefreshMetadata for refreshing metadata about
+ * available applications.
+ *
+ * Caches will be refreshed if they are older than @cache_age_secs.
+ *
+ * Returns: (transfer full): a new #GsPluginJobRefreshMetadata
+ * Since: 42
+ */
+GsPluginJob *
+gs_plugin_job_refresh_metadata_new (guint64                      cache_age_secs,
+                                    GsPluginRefreshMetadataFlags flags)
+{
+	return g_object_new (GS_TYPE_PLUGIN_JOB_REFRESH_METADATA,
+			     "cache-age-secs", cache_age_secs,
+			     "flags", flags,
+			     NULL);
+}
diff --git a/lib/gs-plugin-job-refresh-metadata.h b/lib/gs-plugin-job-refresh-metadata.h
new file mode 100644
index 0000000..94b69c7
--- /dev/null
+++ b/lib/gs-plugin-job-refresh-metadata.h
@@ -0,0 +1,28 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2022 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <glib-object.h>
+#include <gio/gio.h>
+
+#include "gs-plugin-job.h"
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_PLUGIN_JOB_REFRESH_METADATA (gs_plugin_job_refresh_metadata_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsPluginJobRefreshMetadata, gs_plugin_job_refresh_metadata, GS, PLUGIN_JOB_REFRESH_METADATA, GsPluginJob)
+
+GsPluginJob	*gs_plugin_job_refresh_metadata_new	(guint64                      cache_age_secs,
+							 GsPluginRefreshMetadataFlags flags);
+
+G_END_DECLS
diff --git a/lib/gs-plugin-job.c b/lib/gs-plugin-job.c
new file mode 100644
index 0000000..a40980f
--- /dev/null
+++ b/lib/gs-plugin-job.c
@@ -0,0 +1,502 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2017-2018 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2018 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include "config.h"
+
+#include <glib.h>
+
+#include "gs-enums.h"
+#include "gs-plugin-private.h"
+#include "gs-plugin-job-private.h"
+
+typedef struct
+{
+	GsPluginRefineFlags	 refine_flags;
+	GsAppListFilterFlags	 dedupe_flags;
+	gboolean		 interactive;
+	gboolean		 propagate_error;
+	guint			 max_results;
+	GsPlugin		*plugin;
+	GsPluginAction		 action;
+	GsAppListSortFunc	 sort_func;
+	gpointer		 sort_func_data;
+	gchar			*search;
+	GsApp			*app;
+	GsAppList		*list;
+	GFile			*file;
+	gint64			 time_created;
+} GsPluginJobPrivate;
+
+enum {
+	PROP_0,
+	PROP_ACTION,
+	PROP_SEARCH,
+	PROP_REFINE_FLAGS,
+	PROP_DEDUPE_FLAGS,
+	PROP_INTERACTIVE,
+	PROP_APP,
+	PROP_LIST,
+	PROP_FILE,
+	PROP_MAX_RESULTS,
+	PROP_PROPAGATE_ERROR,
+	PROP_LAST
+};
+
+G_DEFINE_TYPE_WITH_PRIVATE (GsPluginJob, gs_plugin_job, G_TYPE_OBJECT)
+
+gchar *
+gs_plugin_job_to_string (GsPluginJob *self)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	GString *str = g_string_new (NULL);
+	gint64 time_now = g_get_monotonic_time ();
+	g_string_append_printf (str, "running %s",
+				gs_plugin_action_to_string (priv->action));
+	if (priv->plugin != NULL) {
+		g_string_append_printf (str, " on plugin=%s",
+					gs_plugin_get_name (priv->plugin));
+	}
+	if (priv->dedupe_flags > 0)
+		g_string_append_printf (str, " with dedupe-flags=%" G_GUINT64_FORMAT, priv->dedupe_flags);
+	if (priv->refine_flags > 0) {
+		g_autofree gchar *tmp = gs_plugin_refine_flags_to_string (priv->refine_flags);
+		g_string_append_printf (str, " with refine-flags=%s", tmp);
+	}
+	if (priv->interactive)
+		g_string_append_printf (str, " with interactive=True");
+	if (priv->propagate_error)
+		g_string_append_printf (str, " with propagate-error=True");
+
+	if (priv->max_results > 0)
+		g_string_append_printf (str, " with max-results=%u", priv->max_results);
+	if (priv->search != NULL) {
+		g_string_append_printf (str, " with search=%s",
+					priv->search);
+	}
+	if (priv->file != NULL) {
+		g_autofree gchar *path = g_file_get_path (priv->file);
+		g_string_append_printf (str, " with file=%s", path);
+	}
+	if (priv->list != NULL && gs_app_list_length (priv->list) > 0) {
+		g_autofree const gchar **unique_ids = NULL;
+		g_autofree gchar *unique_ids_str = NULL;
+		unique_ids = g_new0 (const gchar *, gs_app_list_length (priv->list) + 1);
+		for (guint i = 0; i < gs_app_list_length (priv->list); i++) {
+			GsApp *app = gs_app_list_index (priv->list, i);
+			unique_ids[i] = gs_app_get_unique_id (app);
+		}
+		unique_ids_str = g_strjoinv (",", (gchar**) unique_ids);
+		g_string_append_printf (str, " on apps %s", unique_ids_str);
+	}
+	if (time_now - priv->time_created > 1000) {
+		g_string_append_printf (str, ", elapsed time since creation %" G_GINT64_FORMAT "ms",
+					(time_now - priv->time_created) / 1000);
+	}
+	return g_string_free (str, FALSE);
+}
+
+void
+gs_plugin_job_set_refine_flags (GsPluginJob *self, GsPluginRefineFlags refine_flags)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_if_fail (GS_IS_PLUGIN_JOB (self));
+	priv->refine_flags = refine_flags;
+}
+
+void
+gs_plugin_job_set_dedupe_flags (GsPluginJob *self, GsAppListFilterFlags dedupe_flags)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_if_fail (GS_IS_PLUGIN_JOB (self));
+	priv->dedupe_flags = dedupe_flags;
+}
+
+GsPluginRefineFlags
+gs_plugin_job_get_refine_flags (GsPluginJob *self)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB (self), GS_PLUGIN_REFINE_FLAGS_NONE);
+	return priv->refine_flags;
+}
+
+GsAppListFilterFlags
+gs_plugin_job_get_dedupe_flags (GsPluginJob *self)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB (self), GS_APP_LIST_FILTER_FLAG_NONE);
+	return priv->dedupe_flags;
+}
+
+gboolean
+gs_plugin_job_has_refine_flags (GsPluginJob *self, GsPluginRefineFlags refine_flags)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB (self), FALSE);
+	return (priv->refine_flags & refine_flags) > 0;
+}
+
+void
+gs_plugin_job_add_refine_flags (GsPluginJob *self, GsPluginRefineFlags refine_flags)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_if_fail (GS_IS_PLUGIN_JOB (self));
+	priv->refine_flags |= refine_flags;
+}
+
+void
+gs_plugin_job_remove_refine_flags (GsPluginJob *self, GsPluginRefineFlags refine_flags)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_if_fail (GS_IS_PLUGIN_JOB (self));
+	priv->refine_flags &= ~refine_flags;
+}
+
+void
+gs_plugin_job_set_interactive (GsPluginJob *self, gboolean interactive)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_if_fail (GS_IS_PLUGIN_JOB (self));
+	priv->interactive = interactive;
+}
+
+gboolean
+gs_plugin_job_get_interactive (GsPluginJob *self)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB (self), FALSE);
+	return priv->interactive;
+}
+
+void
+gs_plugin_job_set_propagate_error (GsPluginJob *self, gboolean propagate_error)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_if_fail (GS_IS_PLUGIN_JOB (self));
+	priv->propagate_error = propagate_error;
+}
+
+gboolean
+gs_plugin_job_get_propagate_error (GsPluginJob *self)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB (self), FALSE);
+	return priv->propagate_error;
+}
+
+void
+gs_plugin_job_set_max_results (GsPluginJob *self, guint max_results)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_if_fail (GS_IS_PLUGIN_JOB (self));
+	priv->max_results = max_results;
+}
+
+guint
+gs_plugin_job_get_max_results (GsPluginJob *self)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB (self), 0);
+	return priv->max_results;
+}
+
+void
+gs_plugin_job_set_action (GsPluginJob *self, GsPluginAction action)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_if_fail (GS_IS_PLUGIN_JOB (self));
+	priv->action = action;
+}
+
+GsPluginAction
+gs_plugin_job_get_action (GsPluginJob *self)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB (self), GS_PLUGIN_ACTION_UNKNOWN);
+	return priv->action;
+}
+
+void
+gs_plugin_job_set_sort_func (GsPluginJob *self, GsAppListSortFunc sort_func, gpointer user_data)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_if_fail (GS_IS_PLUGIN_JOB (self));
+	priv->sort_func = sort_func;
+	priv->sort_func_data = user_data;
+}
+
+GsAppListSortFunc
+gs_plugin_job_get_sort_func (GsPluginJob *self, gpointer *user_data_out)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB (self), NULL);
+	if (user_data_out != NULL)
+		*user_data_out = priv->sort_func_data;
+	return priv->sort_func;
+}
+
+void
+gs_plugin_job_set_search (GsPluginJob *self, const gchar *search)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_if_fail (GS_IS_PLUGIN_JOB (self));
+	g_free (priv->search);
+	priv->search = g_strdup (search);
+}
+
+const gchar *
+gs_plugin_job_get_search (GsPluginJob *self)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB (self), NULL);
+	return priv->search;
+}
+
+void
+gs_plugin_job_set_app (GsPluginJob *self, GsApp *app)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_if_fail (GS_IS_PLUGIN_JOB (self));
+	g_set_object (&priv->app, app);
+
+	/* ensure we can always operate on a list object */
+	if (priv->list != NULL && app != NULL && gs_app_list_length (priv->list) == 0)
+		gs_app_list_add (priv->list, priv->app);
+}
+
+GsApp *
+gs_plugin_job_get_app (GsPluginJob *self)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB (self), NULL);
+	return priv->app;
+}
+
+void
+gs_plugin_job_set_list (GsPluginJob *self, GsAppList *list)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_if_fail (GS_IS_PLUGIN_JOB (self));
+	if (list == NULL)
+		g_warning ("trying to set list to NULL, not a good idea");
+	g_set_object (&priv->list, list);
+}
+
+GsAppList *
+gs_plugin_job_get_list (GsPluginJob *self)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB (self), NULL);
+	return priv->list;
+}
+
+void
+gs_plugin_job_set_file (GsPluginJob *self, GFile *file)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_if_fail (GS_IS_PLUGIN_JOB (self));
+	g_set_object (&priv->file, file);
+}
+
+GFile *
+gs_plugin_job_get_file (GsPluginJob *self)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB (self), NULL);
+	return priv->file;
+}
+
+void
+gs_plugin_job_set_plugin (GsPluginJob *self, GsPlugin *plugin)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_if_fail (GS_IS_PLUGIN_JOB (self));
+	g_set_object (&priv->plugin, plugin);
+}
+
+GsPlugin *
+gs_plugin_job_get_plugin (GsPluginJob *self)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+	g_return_val_if_fail (GS_IS_PLUGIN_JOB (self), NULL);
+	return priv->plugin;
+}
+
+static void
+gs_plugin_job_get_property (GObject *obj, guint prop_id, GValue *value, GParamSpec *pspec)
+{
+	GsPluginJob *self = GS_PLUGIN_JOB (obj);
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+
+	switch (prop_id) {
+	case PROP_ACTION:
+		g_value_set_enum (value, priv->action);
+		break;
+	case PROP_REFINE_FLAGS:
+		g_value_set_flags (value, priv->refine_flags);
+		break;
+	case PROP_DEDUPE_FLAGS:
+		g_value_set_flags (value, priv->dedupe_flags);
+		break;
+	case PROP_INTERACTIVE:
+		g_value_set_boolean (value, priv->interactive);
+		break;
+	case PROP_SEARCH:
+		g_value_set_string (value, priv->search);
+		break;
+	case PROP_APP:
+		g_value_set_object (value, priv->app);
+		break;
+	case PROP_LIST:
+		g_value_set_object (value, priv->list);
+		break;
+	case PROP_FILE:
+		g_value_set_object (value, priv->file);
+		break;
+	case PROP_MAX_RESULTS:
+		g_value_set_uint (value, priv->max_results);
+		break;
+	case PROP_PROPAGATE_ERROR:
+		g_value_set_boolean (value, priv->propagate_error);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (obj, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_plugin_job_set_property (GObject *obj, guint prop_id, const GValue *value, GParamSpec *pspec)
+{
+	GsPluginJob *self = GS_PLUGIN_JOB (obj);
+
+	switch (prop_id) {
+	case PROP_ACTION:
+		gs_plugin_job_set_action (self, g_value_get_enum (value));
+		break;
+	case PROP_REFINE_FLAGS:
+		gs_plugin_job_set_refine_flags (self, g_value_get_flags (value));
+		break;
+	case PROP_DEDUPE_FLAGS:
+		gs_plugin_job_set_dedupe_flags (self, g_value_get_flags (value));
+		break;
+	case PROP_INTERACTIVE:
+		gs_plugin_job_set_interactive (self, g_value_get_boolean (value));
+		break;
+	case PROP_SEARCH:
+		gs_plugin_job_set_search (self, g_value_get_string (value));
+		break;
+	case PROP_APP:
+		gs_plugin_job_set_app (self, g_value_get_object (value));
+		break;
+	case PROP_LIST:
+		gs_plugin_job_set_list (self, g_value_get_object (value));
+		break;
+	case PROP_FILE:
+		gs_plugin_job_set_file (self, g_value_get_object (value));
+		break;
+	case PROP_MAX_RESULTS:
+		gs_plugin_job_set_max_results (self, g_value_get_uint (value));
+		break;
+	case PROP_PROPAGATE_ERROR:
+		gs_plugin_job_set_propagate_error (self, g_value_get_boolean (value));
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (obj, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_plugin_job_finalize (GObject *obj)
+{
+	GsPluginJob *self = GS_PLUGIN_JOB (obj);
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+
+	g_free (priv->search);
+	g_clear_object (&priv->app);
+	g_clear_object (&priv->list);
+	g_clear_object (&priv->file);
+	g_clear_object (&priv->plugin);
+
+	G_OBJECT_CLASS (gs_plugin_job_parent_class)->finalize (obj);
+}
+
+static void
+gs_plugin_job_class_init (GsPluginJobClass *klass)
+{
+	GParamSpec *pspec;
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+	object_class->finalize = gs_plugin_job_finalize;
+	object_class->get_property = gs_plugin_job_get_property;
+	object_class->set_property = gs_plugin_job_set_property;
+
+	pspec = g_param_spec_enum ("action", NULL, NULL,
+				   GS_TYPE_PLUGIN_ACTION, GS_PLUGIN_ACTION_UNKNOWN,
+				   G_PARAM_READWRITE);
+	g_object_class_install_property (object_class, PROP_ACTION, pspec);
+
+	pspec = g_param_spec_flags ("refine-flags", NULL, NULL,
+				    GS_TYPE_PLUGIN_REFINE_FLAGS, GS_PLUGIN_REFINE_FLAGS_NONE,
+				    G_PARAM_READWRITE);
+	g_object_class_install_property (object_class, PROP_REFINE_FLAGS, pspec);
+
+	pspec = g_param_spec_flags ("dedupe-flags", NULL, NULL,
+				    GS_TYPE_APP_LIST_FILTER_FLAGS, GS_APP_LIST_FILTER_FLAG_NONE,
+				    G_PARAM_READWRITE);
+	g_object_class_install_property (object_class, PROP_DEDUPE_FLAGS, pspec);
+
+	pspec = g_param_spec_boolean ("interactive", NULL, NULL,
+				      FALSE,
+				      G_PARAM_READWRITE);
+
+	g_object_class_install_property (object_class, PROP_INTERACTIVE, pspec);
+
+	pspec = g_param_spec_string ("search", NULL, NULL,
+				     NULL,
+				     G_PARAM_READWRITE);
+	g_object_class_install_property (object_class, PROP_SEARCH, pspec);
+
+	pspec = g_param_spec_object ("app", NULL, NULL,
+				     GS_TYPE_APP,
+				     G_PARAM_READWRITE);
+	g_object_class_install_property (object_class, PROP_APP, pspec);
+
+	pspec = g_param_spec_object ("list", NULL, NULL,
+				     GS_TYPE_APP_LIST,
+				     G_PARAM_READWRITE);
+	g_object_class_install_property (object_class, PROP_LIST, pspec);
+
+	pspec = g_param_spec_object ("file", NULL, NULL,
+				     G_TYPE_FILE,
+				     G_PARAM_READWRITE);
+	g_object_class_install_property (object_class, PROP_FILE, pspec);
+
+	pspec = g_param_spec_uint ("max-results", NULL, NULL,
+				   0, G_MAXUINT, 0,
+				   G_PARAM_READWRITE);
+	g_object_class_install_property (object_class, PROP_MAX_RESULTS, pspec);
+
+	pspec = g_param_spec_boolean ("propagate-error", NULL, NULL,
+				      FALSE,
+				      G_PARAM_READWRITE);
+	g_object_class_install_property (object_class, PROP_PROPAGATE_ERROR, pspec);
+}
+
+static void
+gs_plugin_job_init (GsPluginJob *self)
+{
+	GsPluginJobPrivate *priv = gs_plugin_job_get_instance_private (self);
+
+	priv->refine_flags = GS_PLUGIN_REFINE_FLAGS_NONE;
+	priv->dedupe_flags = GS_APP_LIST_FILTER_FLAG_KEY_ID |
+			     GS_APP_LIST_FILTER_FLAG_KEY_SOURCE |
+			     GS_APP_LIST_FILTER_FLAG_KEY_VERSION;
+	priv->list = gs_app_list_new ();
+	priv->time_created = g_get_monotonic_time ();
+}
diff --git a/lib/gs-plugin-job.h b/lib/gs-plugin-job.h
new file mode 100644
index 0000000..dcdbc85
--- /dev/null
+++ b/lib/gs-plugin-job.h
@@ -0,0 +1,68 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2017-2018 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib-object.h>
+
+#include "gs-app-list.h"
+#include "gs-plugin-types.h"
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_PLUGIN_JOB (gs_plugin_job_get_type ())
+
+G_DECLARE_DERIVABLE_TYPE (GsPluginJob, gs_plugin_job, GS, PLUGIN_JOB, GObject)
+
+#include "gs-plugin-loader.h"
+
+struct _GsPluginJobClass
+{
+	GObjectClass parent_class;
+
+	void (*run_async) (GsPluginJob         *self,
+	                   GsPluginLoader      *plugin_loader,
+	                   GCancellable        *cancellable,
+	                   GAsyncReadyCallback  callback,
+	                   gpointer             user_data);
+	gboolean (*run_finish) (GsPluginJob   *self,
+	                        GAsyncResult  *result,
+	                        GError       **error);
+};
+
+void		 gs_plugin_job_set_refine_flags		(GsPluginJob	*self,
+							 GsPluginRefineFlags refine_flags);
+void		 gs_plugin_job_set_dedupe_flags		(GsPluginJob	*self,
+							 GsAppListFilterFlags dedupe_flags);
+void		 gs_plugin_job_set_interactive		(GsPluginJob	*self,
+							 gboolean	 interactive);
+void		 gs_plugin_job_set_propagate_error	(GsPluginJob	*self,
+							 gboolean	 propagate_error);
+void		 gs_plugin_job_set_max_results		(GsPluginJob	*self,
+							 guint		 max_results);
+void		 gs_plugin_job_set_sort_func		(GsPluginJob	*self,
+							 GsAppListSortFunc sort_func,
+							 gpointer	 user_data);
+void		 gs_plugin_job_set_search		(GsPluginJob	*self,
+							 const gchar	*search);
+void		 gs_plugin_job_set_app			(GsPluginJob	*self,
+							 GsApp		*app);
+void		 gs_plugin_job_set_list			(GsPluginJob	*self,
+							 GsAppList	*list);
+void		 gs_plugin_job_set_file			(GsPluginJob	*self,
+							 GFile		*file);
+void		 gs_plugin_job_set_plugin		(GsPluginJob	*self,
+							 GsPlugin	*plugin);
+
+#define		 gs_plugin_job_newv(a,...)		GS_PLUGIN_JOB(g_object_new(GS_TYPE_PLUGIN_JOB, "action", a, __VA_ARGS__))
+
+#define		 GS_PLUGIN_JOB_DEDUPE_FLAGS_DEFAULT	(GS_APP_LIST_FILTER_FLAG_KEY_ID | \
+							 GS_APP_LIST_FILTER_FLAG_KEY_SOURCE | \
+							 GS_APP_LIST_FILTER_FLAG_KEY_VERSION)
+
+G_END_DECLS
diff --git a/lib/gs-plugin-loader-sync.c b/lib/gs-plugin-loader-sync.c
new file mode 100644
index 0000000..2b8b39a
--- /dev/null
+++ b/lib/gs-plugin-loader-sync.c
@@ -0,0 +1,254 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2012-2017 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2017 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include "config.h"
+
+#include "gs-plugin-loader-sync.h"
+
+/* tiny helper to help us do the async operation */
+typedef struct {
+	GAsyncResult    *res;
+	GMainContext    *context;
+	GMainLoop	*loop;
+} GsPluginLoaderHelper;
+
+static void
+_helper_finish_sync (GObject *source_object,
+		     GAsyncResult *res,
+		     gpointer user_data)
+{
+	GsPluginLoaderHelper *helper = user_data;
+	helper->res = g_object_ref (res);
+	g_main_loop_quit (helper->loop);
+}
+
+GsAppList *
+gs_plugin_loader_job_process (GsPluginLoader *plugin_loader,
+			      GsPluginJob *plugin_job,
+			      GCancellable *cancellable,
+			      GError **error)
+{
+	GsPluginLoaderHelper helper;
+	GsAppList *list;
+
+	/* create temp object */
+	helper.res = NULL;
+	helper.context = g_main_context_new ();
+	helper.loop = g_main_loop_new (helper.context, FALSE);
+
+	g_main_context_push_thread_default (helper.context);
+
+	/* run async method */
+	gs_plugin_loader_job_process_async (plugin_loader,
+					    plugin_job,
+					    cancellable,
+					    _helper_finish_sync,
+					    &helper);
+	g_main_loop_run (helper.loop);
+	list = gs_plugin_loader_job_process_finish (plugin_loader,
+	                                            helper.res,
+	                                            error);
+
+	g_main_context_pop_thread_default (helper.context);
+
+	g_main_loop_unref (helper.loop);
+	g_main_context_unref (helper.context);
+	if (helper.res != NULL)
+		g_object_unref (helper.res);
+
+	return list;
+}
+
+gboolean
+gs_plugin_loader_job_action (GsPluginLoader *plugin_loader,
+			     GsPluginJob *plugin_job,
+			     GCancellable *cancellable,
+			     GError **error)
+{
+	GsPluginLoaderHelper helper;
+	gboolean ret;
+
+	/* create temp object */
+	helper.res = NULL;
+	helper.context = g_main_context_new ();
+	helper.loop = g_main_loop_new (helper.context, FALSE);
+
+	g_main_context_push_thread_default (helper.context);
+
+	/* run async method */
+	gs_plugin_loader_job_process_async (plugin_loader,
+					    plugin_job,
+					    cancellable,
+					    _helper_finish_sync,
+					    &helper);
+	g_main_loop_run (helper.loop);
+	ret = gs_plugin_loader_job_action_finish (plugin_loader,
+	                                          helper.res,
+	                                          error);
+
+	g_main_context_pop_thread_default (helper.context);
+
+	g_main_loop_unref (helper.loop);
+	g_main_context_unref (helper.context);
+	if (helper.res != NULL)
+		g_object_unref (helper.res);
+
+	return ret;
+}
+
+GsApp *
+gs_plugin_loader_job_process_app (GsPluginLoader *plugin_loader,
+				  GsPluginJob *plugin_job,
+				  GCancellable *cancellable,
+				  GError **error)
+{
+	GsPluginLoaderHelper helper;
+	g_autoptr(GsAppList) list = NULL;
+	GsApp *app = NULL;
+
+	/* create temp object */
+	helper.res = NULL;
+	helper.context = g_main_context_new ();
+	helper.loop = g_main_loop_new (helper.context, FALSE);
+
+	g_main_context_push_thread_default (helper.context);
+
+	/* run async method */
+	gs_plugin_loader_job_process_async (plugin_loader,
+					    plugin_job,
+					    cancellable,
+					    _helper_finish_sync,
+					    &helper);
+	g_main_loop_run (helper.loop);
+	list = gs_plugin_loader_job_process_finish (plugin_loader,
+	                                            helper.res,
+	                                            error);
+	if (list != NULL)
+		app = g_object_ref (gs_app_list_index (list, 0));
+
+	g_main_context_pop_thread_default (helper.context);
+
+	g_main_loop_unref (helper.loop);
+	g_main_context_unref (helper.context);
+	if (helper.res != NULL)
+		g_object_unref (helper.res);
+
+	return app;
+}
+
+GsApp *
+gs_plugin_loader_app_create (GsPluginLoader *plugin_loader,
+			     const gchar *unique_id,
+			     GCancellable *cancellable,
+			     GError **error)
+{
+	GsPluginLoaderHelper helper;
+	GsApp *app;
+
+	/* create temp object */
+	helper.res = NULL;
+	helper.context = g_main_context_new ();
+	helper.loop = g_main_loop_new (helper.context, FALSE);
+
+	g_main_context_push_thread_default (helper.context);
+
+	/* run async method */
+	gs_plugin_loader_app_create_async (plugin_loader,
+					   unique_id,
+					   cancellable,
+					   _helper_finish_sync,
+					   &helper);
+	g_main_loop_run (helper.loop);
+	app = gs_plugin_loader_app_create_finish (plugin_loader,
+						  helper.res,
+						  error);
+
+	g_main_context_pop_thread_default (helper.context);
+
+	g_main_loop_unref (helper.loop);
+	g_main_context_unref (helper.context);
+	if (helper.res != NULL)
+		g_object_unref (helper.res);
+
+	return app;
+}
+
+GsApp *
+gs_plugin_loader_get_system_app (GsPluginLoader *plugin_loader,
+				 GCancellable *cancellable,
+				 GError **error)
+{
+	GsPluginLoaderHelper helper;
+	GsApp *app;
+
+	/* create temp object */
+	helper.res = NULL;
+	helper.context = g_main_context_new ();
+	helper.loop = g_main_loop_new (helper.context, FALSE);
+
+	g_main_context_push_thread_default (helper.context);
+
+	/* run async method */
+	gs_plugin_loader_get_system_app_async (plugin_loader,
+					       cancellable,
+					       _helper_finish_sync,
+					       &helper);
+	g_main_loop_run (helper.loop);
+	app = gs_plugin_loader_get_system_app_finish (plugin_loader,
+						      helper.res,
+						      error);
+
+	g_main_context_pop_thread_default (helper.context);
+
+	g_main_loop_unref (helper.loop);
+	g_main_context_unref (helper.context);
+	if (helper.res != NULL)
+		g_object_unref (helper.res);
+
+	return app;
+}
+
+gboolean
+gs_plugin_loader_setup (GsPluginLoader       *plugin_loader,
+                        const gchar * const  *allowlist,
+                        const gchar * const  *blocklist,
+                        GCancellable         *cancellable,
+                        GError              **error)
+{
+	GsPluginLoaderHelper helper;
+	gboolean retval;
+
+	/* create temp object */
+	helper.res = NULL;
+	helper.context = g_main_context_new ();
+	helper.loop = g_main_loop_new (helper.context, FALSE);
+
+	g_main_context_push_thread_default (helper.context);
+
+	/* run async method */
+	gs_plugin_loader_setup_async (plugin_loader,
+				      allowlist,
+				      blocklist,
+				      cancellable,
+				      _helper_finish_sync,
+				      &helper);
+	g_main_loop_run (helper.loop);
+	retval = gs_plugin_loader_setup_finish (plugin_loader,
+						helper.res,
+						error);
+
+	g_main_context_pop_thread_default (helper.context);
+
+	g_main_loop_unref (helper.loop);
+	g_main_context_unref (helper.context);
+	if (helper.res != NULL)
+		g_object_unref (helper.res);
+
+	return retval;
+}
diff --git a/lib/gs-plugin-loader-sync.h b/lib/gs-plugin-loader-sync.h
new file mode 100644
index 0000000..844e2aa
--- /dev/null
+++ b/lib/gs-plugin-loader-sync.h
@@ -0,0 +1,42 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2007-2017 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib-object.h>
+
+#include "gs-plugin-loader.h"
+
+G_BEGIN_DECLS
+
+GsAppList	*gs_plugin_loader_job_process		(GsPluginLoader	*plugin_loader,
+							 GsPluginJob	*plugin_job,
+							 GCancellable	*cancellable,
+							 GError		**error);
+GsApp		*gs_plugin_loader_job_process_app	(GsPluginLoader	*plugin_loader,
+							 GsPluginJob	*plugin_job,
+							 GCancellable	*cancellable,
+							 GError		**error);
+gboolean	 gs_plugin_loader_job_action		(GsPluginLoader	*plugin_loader,
+							 GsPluginJob	*plugin_job,
+							 GCancellable	*cancellable,
+							 GError		**error);
+GsApp		*gs_plugin_loader_app_create		(GsPluginLoader	*plugin_loader,
+							 const gchar	*unique_id,
+							 GCancellable	*cancellable,
+							 GError		**error);
+GsApp		*gs_plugin_loader_get_system_app	(GsPluginLoader	*plugin_loader,
+							 GCancellable	*cancellable,
+							 GError		**error);
+gboolean	 gs_plugin_loader_setup			(GsPluginLoader	*plugin_loader,
+							 const gchar * const *allowlist,
+							 const gchar * const *blocklist,
+							 GCancellable	 *cancellable,
+							 GError		**error);
+
+G_END_DECLS
diff --git a/lib/gs-plugin-loader.c b/lib/gs-plugin-loader.c
new file mode 100644
index 0000000..d10b1be
--- /dev/null
+++ b/lib/gs-plugin-loader.c
@@ -0,0 +1,4172 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2007-2018 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2014-2020 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include "config.h"
+
+#include <locale.h>
+#include <glib/gi18n.h>
+#include <glib/gstdio.h>
+#include <appstream.h>
+#include <math.h>
+
+#ifdef HAVE_SYSPROF
+#include <sysprof-capture.h>
+#endif
+
+#include "gs-app-collation.h"
+#include "gs-app-private.h"
+#include "gs-app-list-private.h"
+#include "gs-category-manager.h"
+#include "gs-category-private.h"
+#include "gs-external-appstream-utils.h"
+#include "gs-ioprio.h"
+#include "gs-os-release.h"
+#include "gs-plugin-loader.h"
+#include "gs-plugin.h"
+#include "gs-plugin-event.h"
+#include "gs-plugin-job-private.h"
+#include "gs-plugin-private.h"
+#include "gs-utils.h"
+
+#define GS_PLUGIN_LOADER_UPDATES_CHANGED_DELAY	3	/* s */
+#define GS_PLUGIN_LOADER_RELOAD_DELAY		5	/* s */
+
+struct _GsPluginLoader
+{
+	GObject			 parent;
+
+	gboolean		 setup_complete;
+	GCancellable		*setup_complete_cancellable;  /* (nullable) (owned) */
+
+	GPtrArray		*plugins;
+	GPtrArray		*locations;
+	gchar			*language;
+	gboolean		 plugin_dir_dirty;
+	GPtrArray		*file_monitors;
+	GsPluginStatus		 global_status_last;
+
+	GMutex			 pending_apps_mutex;
+	GsAppList		*pending_apps;		/* (nullable) (owned) */
+	GCancellable		*pending_apps_cancellable;  /* (nullable) (owned) */
+
+	GThreadPool		*queued_ops_pool;
+	gint			 active_jobs;
+
+	GSettings		*settings;
+
+	GMutex			 events_by_id_mutex;
+	GHashTable		*events_by_id;		/* unique-id : GsPluginEvent */
+
+	gchar			**compatible_projects;
+	guint			 scale;
+
+	guint			 updates_changed_id;
+	guint			 updates_changed_cnt;
+	guint			 reload_id;
+	GHashTable		*disallow_updates;	/* GsPlugin : const char *name */
+
+	GNetworkMonitor		*network_monitor;
+	gulong			 network_changed_handler;
+	gulong			 network_available_notify_handler;
+	gulong			 network_metered_notify_handler;
+
+	GsCategoryManager	*category_manager;
+	GsOdrsProvider		*odrs_provider;  /* (owned) (nullable) */
+
+#ifdef HAVE_SYSPROF
+	SysprofCaptureWriter	*sysprof_writer;  /* (owned) (nullable) */
+#endif
+
+	GDBusConnection		*session_bus_connection;  /* (owned); (not nullable) after setup */
+	GDBusConnection		*system_bus_connection;  /* (owned); (not nullable) after setup */
+};
+
+static void gs_plugin_loader_monitor_network (GsPluginLoader *plugin_loader);
+static void add_app_to_install_queue (GsPluginLoader *plugin_loader, GsApp *app);
+static gboolean remove_app_from_install_queue (GsPluginLoader *plugin_loader, GsApp *app);
+static void gs_plugin_loader_process_in_thread_pool_cb (gpointer data, gpointer user_data);
+static void gs_plugin_loader_status_changed_cb (GsPlugin       *plugin,
+                                                GsApp          *app,
+                                                GsPluginStatus  status,
+                                                GsPluginLoader *plugin_loader);
+static void async_result_cb (GObject      *source_object,
+                             GAsyncResult *result,
+                             gpointer      user_data);
+
+G_DEFINE_TYPE (GsPluginLoader, gs_plugin_loader, G_TYPE_OBJECT)
+
+enum {
+	SIGNAL_STATUS_CHANGED,
+	SIGNAL_PENDING_APPS_CHANGED,
+	SIGNAL_UPDATES_CHANGED,
+	SIGNAL_RELOAD,
+	SIGNAL_BASIC_AUTH_START,
+	SIGNAL_ASK_UNTRUSTED,
+	SIGNAL_LAST
+};
+
+static guint signals [SIGNAL_LAST] = { 0 };
+
+typedef enum {
+	PROP_EVENTS = 1,
+	PROP_ALLOW_UPDATES,
+	PROP_NETWORK_AVAILABLE,
+	PROP_NETWORK_METERED,
+	PROP_SESSION_BUS_CONNECTION,
+	PROP_SYSTEM_BUS_CONNECTION,
+} GsPluginLoaderProperty;
+
+static GParamSpec *obj_props[PROP_SYSTEM_BUS_CONNECTION + 1] = { NULL, };
+
+typedef void		 (*GsPluginFunc)		(GsPlugin	*plugin);
+typedef gboolean	 (*GsPluginSetupFunc)		(GsPlugin	*plugin,
+							 GCancellable	*cancellable,
+							 GError		**error);
+typedef gboolean	 (*GsPluginSearchFunc)		(GsPlugin	*plugin,
+							 gchar		**value,
+							 GsAppList	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+typedef gboolean	 (*GsPluginAlternatesFunc)	(GsPlugin	*plugin,
+							 GsApp		*app,
+							 GsAppList	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+typedef gboolean	 (*GsPluginCategoryFunc)	(GsPlugin	*plugin,
+							 GsCategory	*category,
+							 GsAppList	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+typedef gboolean	 (*GsPluginGetRecentFunc)	(GsPlugin	*plugin,
+							 GsAppList	*list,
+							 guint64	 age,
+							 GCancellable	*cancellable,
+							 GError		**error);
+typedef gboolean	 (*GsPluginResultsFunc)		(GsPlugin	*plugin,
+							 GsAppList	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+typedef gboolean	 (*GsPluginCategoriesFunc)	(GsPlugin	*plugin,
+							 GPtrArray	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+typedef gboolean	 (*GsPluginActionFunc)		(GsPlugin	*plugin,
+							 GsApp		*app,
+							 GCancellable	*cancellable,
+							 GError		**error);
+typedef gboolean	 (*GsPluginRefreshFunc)		(GsPlugin	*plugin,
+							 guint		 cache_age,
+							 GCancellable	*cancellable,
+							 GError		**error);
+typedef gboolean	 (*GsPluginFileToAppFunc)	(GsPlugin	*plugin,
+							 GsAppList	*list,
+							 GFile		*file,
+							 GCancellable	*cancellable,
+							 GError		**error);
+typedef gboolean	 (*GsPluginUrlToAppFunc)	(GsPlugin	*plugin,
+							 GsAppList	*list,
+							 const gchar	*url,
+							 GCancellable	*cancellable,
+							 GError		**error);
+typedef gboolean	 (*GsPluginUpdateFunc)		(GsPlugin	*plugin,
+							 GsAppList	*apps,
+							 GCancellable	*cancellable,
+							 GError		**error);
+typedef void		 (*GsPluginAdoptAppFunc)	(GsPlugin	*plugin,
+							 GsApp		*app);
+typedef gboolean	 (*GsPluginGetLangPacksFunc)	(GsPlugin	*plugin,
+							 GsAppList	*list,
+							 const gchar    *locale,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+
+/* async helper */
+typedef struct {
+	GsPluginLoader			*plugin_loader;
+	const gchar			*function_name;
+	const gchar			*function_name_parent;
+	GPtrArray			*catlist;
+	GsPluginJob			*plugin_job;
+	gboolean			 anything_ran;
+	gchar				**tokens;
+} GsPluginLoaderHelper;
+
+static GsPluginLoaderHelper *
+gs_plugin_loader_helper_new (GsPluginLoader *plugin_loader, GsPluginJob *plugin_job)
+{
+	GsPluginLoaderHelper *helper = g_slice_new0 (GsPluginLoaderHelper);
+	GsPluginAction action = gs_plugin_job_get_action (plugin_job);
+	helper->plugin_loader = g_object_ref (plugin_loader);
+	helper->plugin_job = g_object_ref (plugin_job);
+	helper->function_name = gs_plugin_action_to_function_name (action);
+	return helper;
+}
+
+static void
+reset_app_progress (GsApp *app)
+{
+	g_autoptr(GsAppList) addons = gs_app_dup_addons (app);
+	GsAppList *related = gs_app_get_related (app);
+
+	gs_app_set_progress (app, GS_APP_PROGRESS_UNKNOWN);
+
+	for (guint i = 0; addons != NULL && i < gs_app_list_length (addons); i++) {
+		GsApp *app_addons = gs_app_list_index (addons, i);
+		gs_app_set_progress (app_addons, GS_APP_PROGRESS_UNKNOWN);
+	}
+	for (guint i = 0; i < gs_app_list_length (related); i++) {
+		GsApp *app_related = gs_app_list_index (related, i);
+		gs_app_set_progress (app_related, GS_APP_PROGRESS_UNKNOWN);
+	}
+}
+
+static void
+gs_plugin_loader_helper_free (GsPluginLoaderHelper *helper)
+{
+	/* reset progress */
+	switch (gs_plugin_job_get_action (helper->plugin_job)) {
+	case GS_PLUGIN_ACTION_INSTALL:
+	case GS_PLUGIN_ACTION_REMOVE:
+	case GS_PLUGIN_ACTION_UPDATE:
+	case GS_PLUGIN_ACTION_DOWNLOAD:
+		{
+			GsApp *app;
+			GsAppList *list;
+
+			app = gs_plugin_job_get_app (helper->plugin_job);
+			if (app != NULL)
+				reset_app_progress (app);
+
+			list = gs_plugin_job_get_list (helper->plugin_job);
+			for (guint i = 0; i < gs_app_list_length (list); i++) {
+				GsApp *app_tmp = gs_app_list_index (list, i);
+				reset_app_progress (app_tmp);
+			}
+		}
+		break;
+	default:
+		break;
+	}
+
+	g_object_unref (helper->plugin_loader);
+	if (helper->plugin_job != NULL)
+		g_object_unref (helper->plugin_job);
+	if (helper->catlist != NULL)
+		g_ptr_array_unref (helper->catlist);
+	g_strfreev (helper->tokens);
+	g_slice_free (GsPluginLoaderHelper, helper);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC(GsPluginLoaderHelper, gs_plugin_loader_helper_free)
+
+GsPlugin *
+gs_plugin_loader_find_plugin (GsPluginLoader *plugin_loader,
+			      const gchar *plugin_name)
+{
+	for (guint i = 0; i < plugin_loader->plugins->len; i++) {
+		GsPlugin *plugin = g_ptr_array_index (plugin_loader->plugins, i);
+		if (g_strcmp0 (gs_plugin_get_name (plugin), plugin_name) == 0)
+			return plugin;
+	}
+	return NULL;
+}
+
+static gboolean
+gs_plugin_loader_notify_idle_cb (gpointer user_data)
+{
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (user_data);
+	g_object_notify_by_pspec (G_OBJECT (plugin_loader), obj_props[PROP_EVENTS]);
+	return FALSE;
+}
+
+void
+gs_plugin_loader_add_event (GsPluginLoader *plugin_loader, GsPluginEvent *event)
+{
+	g_autoptr(GMutexLocker) locker = g_mutex_locker_new (&plugin_loader->events_by_id_mutex);
+
+	/* events should always have a unique ID, either constructed from the
+	 * app they are processing or preferably from the GError message */
+	if (gs_plugin_event_get_unique_id (event) == NULL) {
+		g_warning ("failed to add event from action %s",
+			   gs_plugin_action_to_string (gs_plugin_event_get_action (event)));
+		return;
+	}
+
+	g_hash_table_insert (plugin_loader->events_by_id,
+			     g_strdup (gs_plugin_event_get_unique_id (event)),
+			     g_object_ref (event));
+	g_idle_add (gs_plugin_loader_notify_idle_cb, plugin_loader);
+}
+
+/**
+ * gs_plugin_loader_claim_error:
+ * @plugin_loader: a #GsPluginLoader
+ * @plugin: (nullable): a #GsPlugin to get an application from, or %NULL
+ * @action: a #GsPluginAction associated with the @error
+ * @app: (nullable): a #GsApp for the event, or %NULL
+ * @interactive: whether to set interactive flag
+ * @error: a #GError to claim
+ *
+ * Convert the @error into a plugin event and add it to the queue.
+ *
+ * The @plugin is used only if the @error contains a reference
+ * to a concrete application, in which case any cached application
+ * overrides the passed in @app.
+ *
+ * The %GS_PLUGIN_ERROR_CANCELLED and %G_IO_ERROR_CANCELLED errors
+ * are automatically ignored.
+ *
+ * Since: 41
+ **/
+void
+gs_plugin_loader_claim_error (GsPluginLoader *plugin_loader,
+			      GsPlugin *plugin,
+			      GsPluginAction action,
+			      GsApp *app,
+			      gboolean interactive,
+			      const GError *error)
+{
+	g_autoptr(GError) error_copy = NULL;
+	g_autofree gchar *app_id = NULL;
+	g_autofree gchar *origin_id = NULL;
+	g_autoptr(GsPluginEvent) event = NULL;
+	g_autoptr(GsApp) event_app = NULL;
+	g_autoptr(GsApp) event_origin = NULL;
+
+	g_return_if_fail (GS_IS_PLUGIN_LOADER (plugin_loader));
+	g_return_if_fail (error != NULL);
+
+	if (g_error_matches (error, GS_PLUGIN_ERROR, GS_PLUGIN_ERROR_CANCELLED) ||
+	    g_error_matches (error, G_IO_ERROR, G_IO_ERROR_CANCELLED))
+		return;
+
+	/* find and strip any unique IDs from the error message */
+	error_copy = g_error_copy (error);
+
+	for (guint i = 0; i < 2; i++) {
+		if (app_id == NULL)
+			app_id = gs_utils_error_strip_app_id (error_copy);
+		if (origin_id == NULL)
+			origin_id = gs_utils_error_strip_origin_id (error_copy);
+	}
+
+	/* invalid */
+	if (error_copy->domain != GS_PLUGIN_ERROR) {
+		g_warning ("not GsPlugin error %s:%i: %s",
+			   g_quark_to_string (error_copy->domain),
+			   error_copy->code,
+			   error_copy->message);
+		error_copy->domain = GS_PLUGIN_ERROR;
+		error_copy->code = GS_PLUGIN_ERROR_FAILED;
+	}
+
+	/* set the app and origin IDs if we managed to scrape them from the error above */
+	if (app != NULL)
+		event_app = g_object_ref (app);
+	event_origin = NULL;
+
+	if (plugin != NULL && as_utils_data_id_valid (app_id)) {
+		g_autoptr(GsApp) cached_app = gs_plugin_cache_lookup (plugin, app_id);
+		if (cached_app != NULL) {
+			g_debug ("found app %s in error", app_id);
+			g_set_object (&event_app, cached_app);
+		} else {
+			g_debug ("no unique ID found for app %s", app_id);
+		}
+	}
+	if (plugin != NULL && as_utils_data_id_valid (origin_id)) {
+		g_autoptr(GsApp) origin = gs_plugin_cache_lookup (plugin, origin_id);
+		if (origin != NULL) {
+			g_debug ("found origin %s in error", origin_id);
+			g_set_object (&event_origin, origin);
+		} else {
+			g_debug ("no unique ID found for origin %s", origin_id);
+		}
+	}
+
+	/* create event which is handled by the GsShell */
+	event = gs_plugin_event_new ("error", error_copy,
+				     "action", action,
+				     "app", event_app,
+				     "origin", event_origin,
+				     NULL);
+	if (interactive)
+		gs_plugin_event_add_flag (event, GS_PLUGIN_EVENT_FLAG_INTERACTIVE);
+	gs_plugin_event_add_flag (event, GS_PLUGIN_EVENT_FLAG_WARNING);
+
+	/* add event to the queue */
+	gs_plugin_loader_add_event (plugin_loader, event);
+}
+
+/**
+ * gs_plugin_loader_claim_job_error:
+ * @plugin_loader: a #GsPluginLoader
+ * @plugin: (nullable): a #GsPlugin to get an application from, or %NULL
+ * @job: a #GsPluginJob for the @error
+ * @error: a #GError to claim
+ *
+ * The same as gs_plugin_loader_claim_error(), only reads the information
+ * from the @job.
+ *
+ * Since: 41
+ **/
+void
+gs_plugin_loader_claim_job_error (GsPluginLoader *plugin_loader,
+				  GsPlugin *plugin,
+				  GsPluginJob *job,
+				  const GError *error)
+{
+	g_return_if_fail (GS_IS_PLUGIN_LOADER (plugin_loader));
+	g_return_if_fail (GS_IS_PLUGIN_JOB (job));
+	g_return_if_fail (error != NULL);
+
+	gs_plugin_loader_claim_error (plugin_loader, plugin,
+		gs_plugin_job_get_action (job),
+		gs_plugin_job_get_app (job),
+		gs_plugin_job_get_interactive (job),
+		error);
+}
+
+static gboolean
+gs_plugin_loader_is_error_fatal (const GError *err)
+{
+	if (g_error_matches (err, GS_PLUGIN_ERROR, GS_PLUGIN_ERROR_TIMED_OUT))
+		return TRUE;
+	if (g_error_matches (err, GS_PLUGIN_ERROR, GS_PLUGIN_ERROR_AUTH_REQUIRED))
+		return TRUE;
+	if (g_error_matches (err, GS_PLUGIN_ERROR, GS_PLUGIN_ERROR_AUTH_INVALID))
+		return TRUE;
+	return FALSE;
+}
+
+static gboolean
+gs_plugin_error_handle_failure (GsPluginLoaderHelper *helper,
+				GsPlugin *plugin,
+				const GError *error_local,
+				GError **error)
+{
+	g_autoptr(GError) error_local_copy = NULL;
+	g_autofree gchar *app_id = NULL;
+	g_autofree gchar *origin_id = NULL;
+
+	/* badly behaved plugin */
+	if (error_local == NULL) {
+		g_critical ("%s did not set error for %s",
+			    gs_plugin_get_name (plugin),
+			    helper->function_name);
+		return TRUE;
+	}
+
+	if (gs_plugin_job_get_propagate_error (helper->plugin_job)) {
+		g_propagate_error (error, g_error_copy (error_local));
+		return FALSE;
+	}
+
+	/* this is only ever informational */
+	if (g_error_matches (error_local, GS_PLUGIN_ERROR, GS_PLUGIN_ERROR_CANCELLED) ||
+	    g_error_matches (error_local, G_IO_ERROR, G_IO_ERROR_CANCELLED)) {
+		g_debug ("ignoring error cancelled: %s", error_local->message);
+		return TRUE;
+	}
+
+	/* find and strip any unique IDs from the error message */
+	error_local_copy = g_error_copy (error_local);
+
+	for (guint i = 0; i < 2; i++) {
+		if (app_id == NULL)
+			app_id = gs_utils_error_strip_app_id (error_local_copy);
+		if (origin_id == NULL)
+			origin_id = gs_utils_error_strip_origin_id (error_local_copy);
+	}
+
+	/* fatal error */
+	if (gs_plugin_loader_is_error_fatal (error_local_copy) ||
+	    g_getenv ("GS_SELF_TEST_PLUGIN_ERROR_FAIL_HARD") != NULL) {
+		if (error != NULL)
+			*error = g_steal_pointer (&error_local_copy);
+		return FALSE;
+	}
+
+	gs_plugin_loader_claim_job_error (helper->plugin_loader, plugin, helper->plugin_job, error_local);
+
+	return TRUE;
+}
+
+/**
+ * gs_plugin_loader_run_adopt:
+ * @plugin_loader: a #GsPluginLoader
+ * @list: list of apps to try and adopt
+ *
+ * Call the gs_plugin_adopt_app() function on each plugin on each app in @list
+ * to try and find the plugin which should manage each app.
+ *
+ * This function is intended to be used by internal gnome-software code.
+ *
+ * Since: 42
+ */
+void
+gs_plugin_loader_run_adopt (GsPluginLoader *plugin_loader, GsAppList *list)
+{
+	guint i;
+	guint j;
+
+	/* go through each plugin in order */
+	for (i = 0; i < plugin_loader->plugins->len; i++) {
+		GsPluginAdoptAppFunc adopt_app_func = NULL;
+		GsPlugin *plugin = g_ptr_array_index (plugin_loader->plugins, i);
+		adopt_app_func = gs_plugin_get_symbol (plugin, "gs_plugin_adopt_app");
+		if (adopt_app_func == NULL)
+			continue;
+		for (j = 0; j < gs_app_list_length (list); j++) {
+			GsApp *app = gs_app_list_index (list, j);
+
+			if (gs_app_has_quirk (app, GS_APP_QUIRK_IS_WILDCARD))
+				continue;
+			if (!gs_app_has_management_plugin (app, NULL))
+				continue;
+
+			adopt_app_func (plugin, app);
+
+			if (!gs_app_has_management_plugin (app, NULL)) {
+				g_debug ("%s adopted %s",
+					 gs_plugin_get_name (plugin),
+					 gs_app_get_unique_id (app));
+			}
+		}
+	}
+	for (j = 0; j < gs_app_list_length (list); j++) {
+		GsApp *app = gs_app_list_index (list, j);
+
+		if (gs_app_has_quirk (app, GS_APP_QUIRK_IS_WILDCARD))
+			continue;
+		if (!gs_app_has_management_plugin (app, NULL))
+			continue;
+
+		g_debug ("nothing adopted %s", gs_app_get_unique_id (app));
+	}
+}
+
+static gboolean
+gs_plugin_loader_call_vfunc (GsPluginLoaderHelper *helper,
+			     GsPlugin *plugin,
+			     GsApp *app,
+			     GsAppList *list,
+			     GsPluginRefineFlags refine_flags,
+			     GCancellable *cancellable,
+			     GError **error)
+{
+	GsPluginLoader *plugin_loader = helper->plugin_loader;
+	GsPluginAction action = gs_plugin_job_get_action (helper->plugin_job);
+	gboolean ret = TRUE;
+	gpointer func = NULL;
+	g_autoptr(GError) error_local = NULL;
+	g_autoptr(GTimer) timer = g_timer_new ();
+#ifdef HAVE_SYSPROF
+	gint64 begin_time_nsec = SYSPROF_CAPTURE_CURRENT_TIME;
+#endif
+
+	/* load the possible symbol */
+	func = gs_plugin_get_symbol (plugin, helper->function_name);
+	if (func == NULL)
+		return TRUE;
+
+	/* at least one plugin supports this vfunc */
+	helper->anything_ran = TRUE;
+
+	/* fallback if unset */
+	if (app == NULL)
+		app = gs_plugin_job_get_app (helper->plugin_job);
+	if (list == NULL)
+		list = gs_plugin_job_get_list (helper->plugin_job);
+	if (refine_flags == GS_PLUGIN_REFINE_FLAGS_NONE)
+		refine_flags = gs_plugin_job_get_refine_flags (helper->plugin_job);
+
+	/* set what plugin is running on the job */
+	gs_plugin_job_set_plugin (helper->plugin_job, plugin);
+
+	/* run the correct vfunc */
+	if (gs_plugin_job_get_interactive (helper->plugin_job))
+		gs_plugin_interactive_inc (plugin);
+	switch (action) {
+	case GS_PLUGIN_ACTION_UPDATE:
+		if (g_strcmp0 (helper->function_name, "gs_plugin_update_app") == 0) {
+			GsPluginActionFunc plugin_func = func;
+			ret = plugin_func (plugin, app, cancellable, &error_local);
+		} else if (g_strcmp0 (helper->function_name, "gs_plugin_update") == 0) {
+			GsPluginUpdateFunc plugin_func = func;
+			ret = plugin_func (plugin, list, cancellable, &error_local);
+		} else {
+			g_critical ("function_name %s invalid for %s",
+				    helper->function_name,
+				    gs_plugin_action_to_string (action));
+		}
+		break;
+	case GS_PLUGIN_ACTION_DOWNLOAD:
+		if (g_strcmp0 (helper->function_name, "gs_plugin_download_app") == 0) {
+			GsPluginActionFunc plugin_func = func;
+			ret = plugin_func (plugin, app, cancellable, &error_local);
+		} else if (g_strcmp0 (helper->function_name, "gs_plugin_download") == 0) {
+			GsPluginUpdateFunc plugin_func = func;
+			ret = plugin_func (plugin, list, cancellable, &error_local);
+		} else {
+			g_critical ("function_name %s invalid for %s",
+				    helper->function_name,
+				    gs_plugin_action_to_string (action));
+		}
+		break;
+	case GS_PLUGIN_ACTION_INSTALL:
+	case GS_PLUGIN_ACTION_REMOVE:
+	case GS_PLUGIN_ACTION_UPGRADE_DOWNLOAD:
+	case GS_PLUGIN_ACTION_UPGRADE_TRIGGER:
+	case GS_PLUGIN_ACTION_LAUNCH:
+	case GS_PLUGIN_ACTION_UPDATE_CANCEL:
+		{
+			GsPluginActionFunc plugin_func = func;
+			ret = plugin_func (plugin, app, cancellable, &error_local);
+		}
+		break;
+	case GS_PLUGIN_ACTION_GET_UPDATES:
+	case GS_PLUGIN_ACTION_GET_UPDATES_HISTORICAL:
+	case GS_PLUGIN_ACTION_GET_SOURCES:
+		{
+			GsPluginResultsFunc plugin_func = func;
+			ret = plugin_func (plugin, list, cancellable, &error_local);
+		}
+		break;
+	case GS_PLUGIN_ACTION_FILE_TO_APP:
+		{
+			GsPluginFileToAppFunc plugin_func = func;
+			ret = plugin_func (plugin, list,
+					   gs_plugin_job_get_file (helper->plugin_job),
+					   cancellable, &error_local);
+		}
+		break;
+	case GS_PLUGIN_ACTION_URL_TO_APP:
+		{
+			GsPluginUrlToAppFunc plugin_func = func;
+			ret = plugin_func (plugin, list,
+					   gs_plugin_job_get_search (helper->plugin_job),
+					   cancellable, &error_local);
+		}
+		break;
+	case GS_PLUGIN_ACTION_GET_LANGPACKS:
+		{
+			GsPluginGetLangPacksFunc plugin_func = func;
+			ret = plugin_func (plugin, list,
+					   gs_plugin_job_get_search (helper->plugin_job),
+					   cancellable, &error_local);
+		}
+		break;
+	default:
+		g_critical ("no handler for %s", helper->function_name);
+		break;
+	}
+	if (gs_plugin_job_get_interactive (helper->plugin_job))
+		gs_plugin_interactive_dec (plugin);
+
+	/* plugin did not return error on cancellable abort */
+	if (ret && g_cancellable_set_error_if_cancelled (cancellable, &error_local)) {
+		g_debug ("plugin %s did not return error with cancellable set",
+			 gs_plugin_get_name (plugin));
+		gs_utils_error_convert_gio (&error_local);
+		ret = FALSE;
+	}
+
+	/* failed */
+	if (!ret) {
+		return gs_plugin_error_handle_failure (helper,
+							plugin,
+							error_local,
+							error);
+	}
+
+	/* add app to the pending installation queue if necessary */
+	if (action == GS_PLUGIN_ACTION_INSTALL &&
+	    app != NULL && gs_app_get_state (app) == GS_APP_STATE_QUEUED_FOR_INSTALL) {
+	        add_app_to_install_queue (plugin_loader, app);
+	}
+
+#ifdef HAVE_SYSPROF
+	if (plugin_loader->sysprof_writer != NULL) {
+		g_autofree gchar *sysprof_name = NULL;
+		g_autofree gchar *sysprof_message = NULL;
+
+		sysprof_name = g_strconcat ("vfunc:", gs_plugin_action_to_string (action), NULL);
+		sysprof_message = gs_plugin_job_to_string (helper->plugin_job);
+		sysprof_capture_writer_add_mark (plugin_loader->sysprof_writer,
+						 begin_time_nsec,
+						 sched_getcpu (),
+						 getpid (),
+						 SYSPROF_CAPTURE_CURRENT_TIME - begin_time_nsec,
+						 "gnome-software",
+						 sysprof_name,
+						 sysprof_message);
+	}
+#endif  /* HAVE_SYSPROF */
+
+	/* check the plugin didn't take too long */
+	if (g_timer_elapsed (timer, NULL) > 1.0f) {
+		g_log_structured_standard (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG,
+					   __FILE__, G_STRINGIFY (__LINE__),
+					   G_STRFUNC,
+					   "plugin %s took %.1f seconds to do %s",
+					   gs_plugin_get_name (plugin),
+					   g_timer_elapsed (timer, NULL),
+					   gs_plugin_action_to_string (action));
+	}
+
+	return TRUE;
+}
+
+static void
+gs_plugin_loader_job_sorted_truncation_again (GsPluginJob *plugin_job,
+					      GsAppList *list)
+{
+	GsAppListSortFunc sort_func;
+	gpointer sort_func_data;
+
+	/* not valid */
+	if (list == NULL)
+		return;
+
+	/* unset */
+	sort_func = gs_plugin_job_get_sort_func (plugin_job, &sort_func_data);
+	if (sort_func == NULL)
+		return;
+	gs_app_list_sort (list, sort_func, sort_func_data);
+}
+
+static void
+gs_plugin_loader_job_sorted_truncation (GsPluginJob *plugin_job,
+					GsAppList *list)
+{
+	GsAppListSortFunc sort_func;
+	gpointer sort_func_data;
+	guint max_results;
+
+	/* not valid */
+	if (list == NULL)
+		return;
+
+	/* unset */
+	max_results = gs_plugin_job_get_max_results (plugin_job);
+	if (max_results == 0)
+		return;
+
+	/* already small enough */
+	if (gs_app_list_length (list) <= max_results)
+		return;
+
+	/* nothing set */
+	g_debug ("truncating results to %u from %u",
+		 max_results, gs_app_list_length (list));
+	sort_func = gs_plugin_job_get_sort_func (plugin_job, &sort_func_data);
+	if (sort_func == NULL) {
+		GsPluginAction action = gs_plugin_job_get_action (plugin_job);
+		g_debug ("no ->sort_func() set for %s, using random!",
+			 gs_plugin_action_to_string (action));
+		gs_app_list_randomize (list);
+	} else {
+		gs_app_list_sort (list, sort_func, sort_func_data);
+	}
+	gs_app_list_truncate (list, max_results);
+}
+
+static gboolean
+gs_plugin_loader_run_results (GsPluginLoaderHelper *helper,
+			      GCancellable *cancellable,
+			      GError **error)
+{
+	GsPluginLoader *plugin_loader = helper->plugin_loader;
+#ifdef HAVE_SYSPROF
+	gint64 begin_time_nsec G_GNUC_UNUSED = SYSPROF_CAPTURE_CURRENT_TIME;
+#endif
+
+	/* Refining is done separately as it’s a special action */
+	g_assert (!GS_IS_PLUGIN_JOB_REFINE (helper->plugin_job));
+
+	/* run each plugin */
+	for (guint i = 0; i < plugin_loader->plugins->len; i++) {
+		GsPlugin *plugin = g_ptr_array_index (plugin_loader->plugins, i);
+		if (g_cancellable_set_error_if_cancelled (cancellable, error)) {
+			gs_utils_error_convert_gio (error);
+			return FALSE;
+		}
+		if (!gs_plugin_loader_call_vfunc (helper, plugin, NULL, NULL,
+						  GS_PLUGIN_REFINE_FLAGS_NONE,
+						  cancellable, error)) {
+			return FALSE;
+		}
+		gs_plugin_status_update (plugin, NULL, GS_PLUGIN_STATUS_FINISHED);
+	}
+
+#ifdef HAVE_SYSPROF
+	if (plugin_loader->sysprof_writer != NULL) {
+		g_autofree gchar *sysprof_name = NULL;
+		g_autofree gchar *sysprof_message = NULL;
+
+		sysprof_name = g_strconcat ("run-results:",
+					    gs_plugin_action_to_string (gs_plugin_job_get_action (helper->plugin_job)),
+					    NULL);
+		sysprof_message = gs_plugin_job_to_string (helper->plugin_job);
+		sysprof_capture_writer_add_mark (plugin_loader->sysprof_writer,
+						 begin_time_nsec,
+						 sched_getcpu (),
+						 getpid (),
+						 SYSPROF_CAPTURE_CURRENT_TIME - begin_time_nsec,
+						 "gnome-software",
+						 sysprof_name,
+						 sysprof_message);
+	}
+#endif  /* HAVE_SYSPROF */
+
+	return TRUE;
+}
+
+static const gchar *
+gs_plugin_loader_get_app_str (GsApp *app)
+{
+	const gchar *id;
+
+	/* first try the actual id */
+	id = gs_app_get_unique_id (app);
+	if (id != NULL)
+		return id;
+
+	/* then try the source */
+	id = gs_app_get_source_default (app);
+	if (id != NULL)
+		return id;
+
+	/* lastly try the source id */
+	id = gs_app_get_source_id_default (app);
+	if (id != NULL)
+		return id;
+
+	/* urmmm */
+	return "<invalid>";
+}
+
+gboolean
+gs_plugin_loader_app_is_valid (GsApp               *app,
+                               GsPluginRefineFlags  refine_flags)
+{
+	/* never show addons */
+	if (gs_app_get_kind (app) == AS_COMPONENT_KIND_ADDON) {
+		g_debug ("app invalid as addon %s",
+			 gs_plugin_loader_get_app_str (app));
+		return FALSE;
+	}
+
+	/* never show CLI apps */
+	if (gs_app_get_kind (app) == AS_COMPONENT_KIND_CONSOLE_APP) {
+		g_debug ("app invalid as console %s",
+			 gs_plugin_loader_get_app_str (app));
+		return FALSE;
+	}
+
+	/* don't show unknown state */
+	if (gs_app_get_state (app) == GS_APP_STATE_UNKNOWN) {
+		g_debug ("app invalid as state unknown %s",
+			 gs_plugin_loader_get_app_str (app));
+		return FALSE;
+	}
+
+	/* don't show unconverted unavailables */
+	if (gs_app_get_kind (app) == AS_COMPONENT_KIND_UNKNOWN &&
+		gs_app_get_state (app) == GS_APP_STATE_UNAVAILABLE) {
+		g_debug ("app invalid as unconverted unavailable %s",
+			 gs_plugin_loader_get_app_str (app));
+		return FALSE;
+	}
+
+	/* don't show blocklisted apps */
+	if (gs_app_has_quirk (app, GS_APP_QUIRK_HIDE_EVERYWHERE)) {
+		g_debug ("app invalid as blocklisted %s",
+			 gs_plugin_loader_get_app_str (app));
+		return FALSE;
+	}
+
+	/* Don’t show parentally filtered apps unless they’re already
+	 * installed. See the comments in gs-details-page.c for details. */
+	if (!gs_app_is_installed (app) &&
+	    gs_app_has_quirk (app, GS_APP_QUIRK_PARENTAL_FILTER)) {
+		g_debug ("app invalid as parentally filtered %s",
+		         gs_plugin_loader_get_app_str (app));
+		return FALSE;
+	}
+
+	/* don't show apps with hide-from-search quirk, unless they are already installed */
+	if (!gs_app_is_installed (app) &&
+	    gs_app_has_quirk (app, GS_APP_QUIRK_HIDE_FROM_SEARCH)) {
+		g_debug ("app invalid as hide-from-search quirk set %s",
+		         gs_plugin_loader_get_app_str (app));
+		return FALSE;
+	}
+
+	/* don't show sources */
+	if (gs_app_get_kind (app) == AS_COMPONENT_KIND_REPOSITORY) {
+		g_debug ("app invalid as source %s",
+			 gs_plugin_loader_get_app_str (app));
+		return FALSE;
+	}
+
+	/* don't show unknown kind */
+	if (gs_app_get_kind (app) == AS_COMPONENT_KIND_UNKNOWN) {
+		g_debug ("app invalid as kind unknown %s",
+			 gs_plugin_loader_get_app_str (app));
+		return FALSE;
+	}
+
+	/* don't show unconverted packages in the application view */
+	if (!(refine_flags & GS_PLUGIN_REFINE_FLAGS_ALLOW_PACKAGES) &&
+	    gs_app_get_kind (app) == AS_COMPONENT_KIND_GENERIC &&
+	    gs_app_get_special_kind (app) == GS_APP_SPECIAL_KIND_NONE) {
+		g_debug ("app invalid as only a %s: %s",
+			 as_component_kind_to_string (gs_app_get_kind (app)),
+			 gs_plugin_loader_get_app_str (app));
+		return FALSE;
+	}
+
+	/* don't show apps that do not have the required details */
+	if (gs_app_get_name (app) == NULL) {
+		g_debug ("app invalid as no name %s",
+			 gs_plugin_loader_get_app_str (app));
+		return FALSE;
+	}
+	if (gs_app_get_summary (app) == NULL) {
+		g_debug ("app invalid as no summary %s",
+			 gs_plugin_loader_get_app_str (app));
+		return FALSE;
+	}
+
+	/* ignore this crazy application */
+	if (g_strcmp0 (gs_app_get_id (app), "gnome-system-monitor-kde.desktop") == 0) {
+		g_debug ("Ignoring KDE version of %s", gs_app_get_id (app));
+		return FALSE;
+	}
+	return TRUE;
+}
+
+static gboolean
+gs_plugin_loader_app_is_valid_filter (GsApp    *app,
+                                      gpointer  user_data)
+{
+	GsPluginLoaderHelper *helper = (GsPluginLoaderHelper *) user_data;
+
+	return gs_plugin_loader_app_is_valid (app, gs_plugin_job_get_refine_flags (helper->plugin_job));
+}
+
+static gboolean
+gs_plugin_loader_app_is_valid_updatable (GsApp *app, gpointer user_data)
+{
+	return gs_plugin_loader_app_is_valid_filter (app, user_data) &&
+		(gs_app_is_updatable (app) || gs_app_get_state (app) == GS_APP_STATE_INSTALLING);
+}
+
+gboolean
+gs_plugin_loader_app_is_compatible (GsPluginLoader *plugin_loader,
+                                    GsApp          *app)
+{
+	const gchar *tmp;
+	guint i;
+
+	/* search for any compatible projects */
+	tmp = gs_app_get_project_group (app);
+	if (tmp == NULL)
+		return TRUE;
+	for (i = 0; plugin_loader->compatible_projects[i] != NULL; i++) {
+		if (g_strcmp0 (tmp,  plugin_loader->compatible_projects[i]) == 0)
+			return TRUE;
+	}
+	g_debug ("removing incompatible %s from project group %s",
+		 gs_app_get_id (app), gs_app_get_project_group (app));
+	return FALSE;
+}
+
+/******************************************************************************/
+
+/**
+ * gs_plugin_loader_job_process_finish:
+ * @plugin_loader: A #GsPluginLoader
+ * @res: a #GAsyncResult
+ * @error: A #GError, or %NULL
+ *
+ * Return value: (element-type GsApp) (transfer full): A list of applications
+ **/
+GsAppList *
+gs_plugin_loader_job_process_finish (GsPluginLoader *plugin_loader,
+				     GAsyncResult *res,
+				     GError **error)
+{
+	GTask *task;
+	GsAppList *list = NULL;
+
+	g_return_val_if_fail (GS_IS_PLUGIN_LOADER (plugin_loader), NULL);
+	g_return_val_if_fail (G_IS_TASK (res), NULL);
+	g_return_val_if_fail (g_task_is_valid (res, plugin_loader), NULL);
+	g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+
+	task = G_TASK (res);
+
+	/* Return cancelled if the task was cancelled and there is no other error set.
+	 *
+	 * This is needed because we set the task `check_cancellable` to FALSE,
+	 * to be able to catch other errors such as timeout, but that means
+	 * g_task_propagate_pointer() will ignore if the task was cancelled and only
+	 * check if there was an error (i.e. g_task_return_*error*).
+	 *
+	 * We only do this if there is no error already set in the task (e.g.
+	 * timeout) because in that case we want to return the existing error.
+	 */
+	if (!g_task_had_error (task)) {
+		GCancellable *cancellable = g_task_get_cancellable (task);
+
+		if (g_cancellable_set_error_if_cancelled (cancellable, error)) {
+			gs_utils_error_convert_gio (error);
+			return NULL;
+		}
+	}
+	list = g_task_propagate_pointer (task, error);
+	gs_utils_error_convert_gio (error);
+	return list;
+}
+
+/**
+ * gs_plugin_loader_job_action_finish:
+ * @plugin_loader: A #GsPluginLoader
+ * @res: a #GAsyncResult
+ * @error: A #GError, or %NULL
+ *
+ * Return value: success
+ **/
+gboolean
+gs_plugin_loader_job_action_finish (GsPluginLoader *plugin_loader,
+				     GAsyncResult *res,
+				     GError **error)
+{
+	g_autoptr(GsAppList) list = NULL;
+
+	g_return_val_if_fail (GS_IS_PLUGIN_LOADER (plugin_loader), FALSE);
+	g_return_val_if_fail (G_IS_TASK (res), FALSE);
+	g_return_val_if_fail (g_task_is_valid (res, plugin_loader), FALSE);
+	g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
+
+	list = g_task_propagate_pointer (G_TASK (res), error);
+	return list != NULL;
+}
+
+/******************************************************************************/
+
+static gboolean
+emit_pending_apps_idle (gpointer loader)
+{
+	g_signal_emit (loader, signals[SIGNAL_PENDING_APPS_CHANGED], 0);
+	g_object_unref (loader);
+
+	return G_SOURCE_REMOVE;
+}
+
+static void
+gs_plugin_loader_pending_apps_add (GsPluginLoader *plugin_loader,
+				   GsPluginLoaderHelper *helper)
+{
+	GsAppList *list = gs_plugin_job_get_list (helper->plugin_job);
+
+	g_assert (gs_app_list_length (list) > 0);
+	for (guint i = 0; i < gs_app_list_length (list); i++) {
+		GsApp *app = gs_app_list_index (list, i);
+		switch (gs_plugin_job_get_action (helper->plugin_job)) {
+		case GS_PLUGIN_ACTION_INSTALL:
+			if (gs_app_get_state (app) != GS_APP_STATE_AVAILABLE_LOCAL)
+				add_app_to_install_queue (plugin_loader, app);
+			/* make sure the progress is properly initialized */
+			gs_app_set_progress (app, GS_APP_PROGRESS_UNKNOWN);
+			break;
+		case GS_PLUGIN_ACTION_REMOVE:
+			remove_app_from_install_queue (plugin_loader, app);
+			break;
+		default:
+			break;
+		}
+	}
+	g_idle_add (emit_pending_apps_idle, g_object_ref (plugin_loader));
+}
+
+static void
+gs_plugin_loader_pending_apps_remove (GsPluginLoader *plugin_loader,
+				      GsPluginLoaderHelper *helper)
+{
+	GsAppList *list = gs_plugin_job_get_list (helper->plugin_job);
+
+	g_assert (gs_app_list_length (list) > 0);
+	for (guint i = 0; i < gs_app_list_length (list); i++) {
+		GsApp *app = gs_app_list_index (list, i);
+		remove_app_from_install_queue (plugin_loader, app);
+
+		/* check the app is not still in an action helper */
+		switch (gs_app_get_state (app)) {
+		case GS_APP_STATE_INSTALLING:
+		case GS_APP_STATE_REMOVING:
+			g_warning ("application %s left in %s helper",
+				   gs_app_get_unique_id (app),
+				   gs_app_state_to_string (gs_app_get_state (app)));
+			gs_app_set_state (app, GS_APP_STATE_UNKNOWN);
+			break;
+		default:
+			break;
+		}
+
+	}
+	g_idle_add (emit_pending_apps_idle, g_object_ref (plugin_loader));
+}
+
+static void
+async_result_cb (GObject      *source_object,
+                 GAsyncResult *result,
+                 gpointer      user_data)
+{
+	GAsyncResult **result_out = user_data;
+
+	*result_out = g_object_ref (result);
+	g_main_context_wakeup (g_main_context_get_thread_default ());
+}
+
+/* This will load the install queue and add it to #GsPluginLoader.pending_apps,
+ * but it won’t refine the loaded apps. */
+static GsAppList *
+load_install_queue (GsPluginLoader  *plugin_loader,
+                    GError         **error)
+{
+	g_autofree gchar *contents = NULL;
+	g_autofree gchar *file = NULL;
+	g_auto(GStrv) names = NULL;
+	g_autoptr(GsAppList) list = NULL;
+
+	/* load from file */
+	file = g_build_filename (g_get_user_data_dir (),
+				 "gnome-software",
+				 "install-queue",
+				 NULL);
+	if (!g_file_test (file, G_FILE_TEST_EXISTS))
+		return gs_app_list_new ();
+
+	g_debug ("loading install queue from %s", file);
+	if (!g_file_get_contents (file, &contents, NULL, error))
+		return NULL;
+
+	/* add to GsAppList, deduplicating if required */
+	list = gs_app_list_new ();
+	names = g_strsplit (contents, "\n", 0);
+	for (guint i = 0; names[i] != NULL; i++) {
+		g_autoptr(GsApp) app = NULL;
+		g_auto(GStrv) split = g_strsplit (names[i], "\t", -1);
+		if (split[0] == NULL || split[1] == NULL)
+			continue;
+		app = gs_app_new (NULL);
+		gs_app_set_from_unique_id (app, split[0], as_component_kind_from_string (split[1]));
+		gs_app_set_state (app, GS_APP_STATE_QUEUED_FOR_INSTALL);
+		gs_app_add_quirk (app, GS_APP_QUIRK_IS_WILDCARD);
+		gs_app_list_add (list, app);
+	}
+
+	/* add to pending list */
+	g_mutex_lock (&plugin_loader->pending_apps_mutex);
+	for (guint i = 0; i < gs_app_list_length (list); i++) {
+		GsApp *app = gs_app_list_index (list, i);
+		g_debug ("adding pending app %s", gs_app_get_unique_id (app));
+		if (plugin_loader->pending_apps == NULL)
+			plugin_loader->pending_apps = gs_app_list_new ();
+		gs_app_list_add (plugin_loader->pending_apps, app);
+	}
+	g_mutex_unlock (&plugin_loader->pending_apps_mutex);
+
+	return g_steal_pointer (&list);
+}
+
+static void
+save_install_queue (GsPluginLoader *plugin_loader)
+{
+	gboolean ret;
+	g_autoptr(GError) error = NULL;
+	g_autoptr(GString) s = NULL;
+	g_autofree gchar *file = NULL;
+
+	s = g_string_new ("");
+	g_mutex_lock (&plugin_loader->pending_apps_mutex);
+	for (guint i = 0; plugin_loader->pending_apps != NULL && i < gs_app_list_length (plugin_loader->pending_apps); i++) {
+		GsApp *app = gs_app_list_index (plugin_loader->pending_apps, i);
+		if (gs_app_get_state (app) == GS_APP_STATE_QUEUED_FOR_INSTALL) {
+			g_string_append (s, gs_app_get_unique_id (app));
+			g_string_append_c (s, '\t');
+			g_string_append (s, as_component_kind_to_string (gs_app_get_kind (app)));
+			g_string_append_c (s, '\n');
+		}
+	}
+	g_mutex_unlock (&plugin_loader->pending_apps_mutex);
+
+	/* save file */
+	file = g_build_filename (g_get_user_data_dir (),
+				 "gnome-software",
+				 "install-queue",
+				 NULL);
+	if (s->len == 0) {
+		if (g_unlink (file) == -1 && errno != ENOENT) {
+			gint errn = errno;
+			g_warning ("Failed to unlink '%s': %s", file, g_strerror (errn));
+		}
+		return;
+	}
+
+	if (!gs_mkdir_parent (file, &error)) {
+		g_warning ("failed to create dir for %s: %s",
+			   file, error->message);
+		return;
+	}
+	g_debug ("saving install queue to %s", file);
+	ret = g_file_set_contents (file, s->str, (gssize) s->len, &error);
+	if (!ret)
+		g_warning ("failed to save install queue: %s", error->message);
+}
+
+static void
+add_app_to_install_queue (GsPluginLoader *plugin_loader, GsApp *app)
+{
+	g_autoptr(GsAppList) addons = NULL;
+	g_autoptr(GSource) source = NULL;
+	guint i;
+
+	/* queue the app itself */
+	g_mutex_lock (&plugin_loader->pending_apps_mutex);
+	if (plugin_loader->pending_apps == NULL)
+		plugin_loader->pending_apps = gs_app_list_new ();
+	gs_app_list_add (plugin_loader->pending_apps, app);
+	g_mutex_unlock (&plugin_loader->pending_apps_mutex);
+
+	gs_app_set_state (app, GS_APP_STATE_QUEUED_FOR_INSTALL);
+
+	source = g_idle_source_new ();
+	g_source_set_callback (source, emit_pending_apps_idle, g_object_ref (plugin_loader), NULL);
+	g_source_set_name (source, "[gnome-software] emit_pending_apps_idle");
+	g_source_attach (source, NULL);
+
+	save_install_queue (plugin_loader);
+
+	/* recursively queue any addons */
+	addons = gs_app_dup_addons (app);
+	for (i = 0; addons != NULL && i < gs_app_list_length (addons); i++) {
+		GsApp *addon = gs_app_list_index (addons, i);
+		if (gs_app_get_to_be_installed (addon))
+			add_app_to_install_queue (plugin_loader, addon);
+	}
+}
+
+static gboolean
+remove_app_from_install_queue (GsPluginLoader *plugin_loader, GsApp *app)
+{
+	g_autoptr(GsAppList) addons = NULL;
+	gboolean ret;
+	guint i;
+
+	g_mutex_lock (&plugin_loader->pending_apps_mutex);
+	ret = plugin_loader->pending_apps != NULL && gs_app_list_remove (plugin_loader->pending_apps, app);
+	g_mutex_unlock (&plugin_loader->pending_apps_mutex);
+
+	if (ret) {
+		g_autoptr(GSource) source = NULL;
+
+		if (gs_app_get_state (app) == GS_APP_STATE_QUEUED_FOR_INSTALL)
+			gs_app_set_state (app, GS_APP_STATE_UNKNOWN);
+
+		source = g_idle_source_new ();
+		g_source_set_callback (source, emit_pending_apps_idle, g_object_ref (plugin_loader), NULL);
+		g_source_set_name (source, "[gnome-software] emit_pending_apps_idle");
+		g_source_attach (source, NULL);
+
+		save_install_queue (plugin_loader);
+
+		/* recursively remove any queued addons */
+		addons = gs_app_dup_addons (app);
+		for (i = 0; addons != NULL && i < gs_app_list_length (addons); i++) {
+			GsApp *addon = gs_app_list_index (addons, i);
+			remove_app_from_install_queue (plugin_loader, addon);
+		}
+	}
+
+	return ret;
+}
+
+/******************************************************************************/
+
+gboolean
+gs_plugin_loader_get_allow_updates (GsPluginLoader *plugin_loader)
+{
+	GHashTableIter iter;
+	gpointer value;
+
+	/* nothing */
+	if (g_hash_table_size (plugin_loader->disallow_updates) == 0)
+		return TRUE;
+
+	/* list */
+	g_hash_table_iter_init (&iter, plugin_loader->disallow_updates);
+	while (g_hash_table_iter_next (&iter, NULL, &value)) {
+		const gchar *reason = value;
+		g_debug ("managed updates inhibited by %s", reason);
+	}
+	return FALSE;
+}
+
+GsAppList *
+gs_plugin_loader_get_pending (GsPluginLoader *plugin_loader)
+{
+	GsAppList *array;
+
+	array = gs_app_list_new ();
+	g_mutex_lock (&plugin_loader->pending_apps_mutex);
+	if (plugin_loader->pending_apps != NULL)
+		gs_app_list_add_list (array, plugin_loader->pending_apps);
+	g_mutex_unlock (&plugin_loader->pending_apps_mutex);
+
+	return array;
+}
+
+gboolean
+gs_plugin_loader_get_enabled (GsPluginLoader *plugin_loader,
+			      const gchar *plugin_name)
+{
+	GsPlugin *plugin;
+	plugin = gs_plugin_loader_find_plugin (plugin_loader, plugin_name);
+	if (plugin == NULL)
+		return FALSE;
+	return gs_plugin_get_enabled (plugin);
+}
+
+/**
+ * gs_plugin_loader_get_events:
+ * @plugin_loader: A #GsPluginLoader
+ *
+ * Gets all plugin events, even ones that are not active or visible anymore.
+ *
+ * Returns: (transfer container) (element-type GsPluginEvent): events
+ **/
+GPtrArray *
+gs_plugin_loader_get_events (GsPluginLoader *plugin_loader)
+{
+	GPtrArray *events = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);
+	g_autoptr(GMutexLocker) locker = g_mutex_locker_new (&plugin_loader->events_by_id_mutex);
+	GHashTableIter iter;
+	gpointer key, value;
+
+	/* just add everything */
+	g_hash_table_iter_init (&iter, plugin_loader->events_by_id);
+	while (g_hash_table_iter_next (&iter, &key, &value)) {
+		const gchar *id = key;
+		GsPluginEvent *event = value;
+		if (event == NULL) {
+			g_warning ("failed to get event for '%s'", id);
+			continue;
+		}
+		g_ptr_array_add (events, g_object_ref (event));
+	}
+	return events;
+}
+
+/**
+ * gs_plugin_loader_get_event_default:
+ * @plugin_loader: A #GsPluginLoader
+ *
+ * Gets an active plugin event where active means that it was not been
+ * already dismissed by the user.
+ *
+ * Returns: (transfer full): a #GsPluginEvent, or %NULL for none
+ **/
+GsPluginEvent *
+gs_plugin_loader_get_event_default (GsPluginLoader *plugin_loader)
+{
+	g_autoptr(GMutexLocker) locker = g_mutex_locker_new (&plugin_loader->events_by_id_mutex);
+	GHashTableIter iter;
+	gpointer key, value;
+
+	/* just add everything */
+	g_hash_table_iter_init (&iter, plugin_loader->events_by_id);
+	while (g_hash_table_iter_next (&iter, &key, &value)) {
+		const gchar *id = key;
+		GsPluginEvent *event = value;
+		if (event == NULL) {
+			g_warning ("failed to get event for '%s'", id);
+			continue;
+		}
+		if (!gs_plugin_event_has_flag (event, GS_PLUGIN_EVENT_FLAG_INVALID))
+			return g_object_ref (event);
+	}
+	return NULL;
+}
+
+/**
+ * gs_plugin_loader_remove_events:
+ * @plugin_loader: A #GsPluginLoader
+ *
+ * Removes all plugin events from the loader. This function should only be
+ * called from the self tests.
+ **/
+void
+gs_plugin_loader_remove_events (GsPluginLoader *plugin_loader)
+{
+	g_autoptr(GMutexLocker) locker = g_mutex_locker_new (&plugin_loader->events_by_id_mutex);
+	g_hash_table_remove_all (plugin_loader->events_by_id);
+}
+
+static void
+gs_plugin_loader_report_event_cb (GsPlugin *plugin,
+				  GsPluginEvent *event,
+				  GsPluginLoader *plugin_loader)
+{
+	if (gs_plugin_has_flags (plugin, GS_PLUGIN_FLAGS_INTERACTIVE))
+		gs_plugin_event_add_flag (event, GS_PLUGIN_EVENT_FLAG_INTERACTIVE);
+	gs_plugin_loader_add_event (plugin_loader, event);
+}
+
+static void
+gs_plugin_loader_allow_updates_cb (GsPlugin *plugin,
+				   gboolean allow_updates,
+				   GsPluginLoader *plugin_loader)
+{
+	gboolean changed = FALSE;
+
+	/* plugin now allowing gnome-software to show updates panel */
+	if (allow_updates) {
+		if (g_hash_table_remove (plugin_loader->disallow_updates, plugin)) {
+			g_debug ("plugin %s no longer inhibited managed updates",
+				 gs_plugin_get_name (plugin));
+			changed = TRUE;
+		}
+
+	/* plugin preventing the updates panel from being shown */
+	} else {
+		if (g_hash_table_replace (plugin_loader->disallow_updates,
+					  (gpointer) plugin,
+					  (gpointer) gs_plugin_get_name (plugin))) {
+			g_debug ("plugin %s inhibited managed updates",
+				 gs_plugin_get_name (plugin));
+			changed = TRUE;
+		}
+	}
+
+	/* notify display layer */
+	if (changed)
+		g_object_notify_by_pspec (G_OBJECT (plugin_loader), obj_props[PROP_ALLOW_UPDATES]);
+}
+
+static void
+gs_plugin_loader_status_changed_cb (GsPlugin *plugin,
+				    GsApp *app,
+				    GsPluginStatus status,
+				    GsPluginLoader *plugin_loader)
+{
+	/* nothing specific */
+	if (app == NULL || gs_app_get_id (app) == NULL) {
+		if (plugin_loader->global_status_last != status) {
+			g_debug ("emitting global %s",
+				 gs_plugin_status_to_string (status));
+			g_signal_emit (plugin_loader,
+				       signals[SIGNAL_STATUS_CHANGED],
+				       0, app, status);
+			plugin_loader->global_status_last = status;
+		}
+		return;
+	}
+
+	/* a specific app */
+	g_debug ("emitting %s(%s)",
+		 gs_plugin_status_to_string (status),
+		 gs_app_get_id (app));
+	g_signal_emit (plugin_loader,
+		       signals[SIGNAL_STATUS_CHANGED],
+		       0, app, status);
+}
+
+static void
+gs_plugin_loader_basic_auth_start_cb (GsPlugin *plugin,
+                                      const gchar *remote,
+                                      const gchar *realm,
+                                      GCallback callback,
+                                      gpointer user_data,
+                                      GsPluginLoader *plugin_loader)
+{
+	g_debug ("emitting basic-auth-start %s", realm);
+	g_signal_emit (plugin_loader,
+		       signals[SIGNAL_BASIC_AUTH_START], 0,
+		       remote,
+		       realm,
+		       callback,
+		       user_data);
+}
+
+static gboolean
+gs_plugin_loader_ask_untrusted_cb (GsPlugin *plugin,
+				   const gchar *title,
+				   const gchar *msg,
+				   const gchar *details,
+				   const gchar *accept_label,
+				   GsPluginLoader *plugin_loader)
+{
+	gboolean accepts = FALSE;
+	g_debug ("emitting ask-untrusted title:'%s', msg:'%s' details:'%s' accept-label:'%s'", title, msg, details, accept_label);
+	g_signal_emit (plugin_loader,
+		       signals[SIGNAL_ASK_UNTRUSTED], 0,
+		       title, msg, details, accept_label, &accepts);
+	return accepts;
+}
+
+static gboolean
+gs_plugin_loader_job_updates_changed_delay_cb (gpointer user_data)
+{
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (user_data);
+
+	/* notify shells */
+	g_debug ("updates-changed");
+	g_signal_emit (plugin_loader, signals[SIGNAL_UPDATES_CHANGED], 0);
+	plugin_loader->updates_changed_id = 0;
+	plugin_loader->updates_changed_cnt = 0;
+
+	return FALSE;
+}
+
+static void
+gs_plugin_loader_updates_changed (GsPluginLoader *plugin_loader)
+{
+	if (plugin_loader->updates_changed_id != 0)
+		return;
+	plugin_loader->updates_changed_id =
+		g_timeout_add_seconds_full (G_PRIORITY_DEFAULT,
+					    GS_PLUGIN_LOADER_UPDATES_CHANGED_DELAY,
+					    gs_plugin_loader_job_updates_changed_delay_cb,
+					    g_object_ref (plugin_loader),
+					    g_object_unref);
+}
+
+static void
+gs_plugin_loader_job_updates_changed_cb (GsPlugin *plugin,
+					 GsPluginLoader *plugin_loader)
+{
+	plugin_loader->updates_changed_cnt++;
+
+	/* Schedule emit of updates changed when no job is active.
+	   This helps to avoid a race condition when a plugin calls
+	   updates-changed at the end of the job, but the job is
+	   finished before the callback gets called in the main thread. */
+	if (!g_atomic_int_get (&plugin_loader->active_jobs))
+		gs_plugin_loader_updates_changed (plugin_loader);
+}
+
+static gboolean
+gs_plugin_loader_reload_delay_cb (gpointer user_data)
+{
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (user_data);
+
+	/* notify shells */
+	g_debug ("emitting ::reload");
+	g_signal_emit (plugin_loader, signals[SIGNAL_RELOAD], 0);
+	plugin_loader->reload_id = 0;
+
+	g_object_unref (plugin_loader);
+	return FALSE;
+}
+
+static void
+gs_plugin_loader_reload_cb (GsPlugin *plugin,
+			    GsPluginLoader *plugin_loader)
+{
+	if (plugin_loader->reload_id != 0)
+		return;
+	plugin_loader->reload_id =
+		g_timeout_add_seconds (GS_PLUGIN_LOADER_RELOAD_DELAY,
+				       gs_plugin_loader_reload_delay_cb,
+				       g_object_ref (plugin_loader));
+}
+
+static void
+gs_plugin_loader_repository_changed_cb (GsPlugin *plugin,
+					GsApp *repository,
+					GsPluginLoader *plugin_loader)
+{
+	GApplication *application = g_application_get_default ();
+
+	/* Can be NULL when running the self tests */
+	if (application) {
+		g_signal_emit_by_name (application,
+			"repository-changed",
+			repository);
+	}
+}
+
+static void
+gs_plugin_loader_open_plugin (GsPluginLoader *plugin_loader,
+			      const gchar *filename)
+{
+	GsPlugin *plugin;
+	g_autoptr(GError) error = NULL;
+
+	/* create plugin from file */
+	plugin = gs_plugin_create (filename,
+				   plugin_loader->session_bus_connection,
+				   plugin_loader->system_bus_connection,
+				   &error);
+	if (plugin == NULL) {
+		g_warning ("Failed to load %s: %s", filename, error->message);
+		return;
+	}
+	g_signal_connect (plugin, "updates-changed",
+			  G_CALLBACK (gs_plugin_loader_job_updates_changed_cb),
+			  plugin_loader);
+	g_signal_connect (plugin, "reload",
+			  G_CALLBACK (gs_plugin_loader_reload_cb),
+			  plugin_loader);
+	g_signal_connect (plugin, "status-changed",
+			  G_CALLBACK (gs_plugin_loader_status_changed_cb),
+			  plugin_loader);
+	g_signal_connect (plugin, "basic-auth-start",
+			  G_CALLBACK (gs_plugin_loader_basic_auth_start_cb),
+			  plugin_loader);
+	g_signal_connect (plugin, "report-event",
+			  G_CALLBACK (gs_plugin_loader_report_event_cb),
+			  plugin_loader);
+	g_signal_connect (plugin, "allow-updates",
+			  G_CALLBACK (gs_plugin_loader_allow_updates_cb),
+			  plugin_loader);
+	g_signal_connect (plugin, "repository-changed",
+			  G_CALLBACK (gs_plugin_loader_repository_changed_cb),
+			  plugin_loader);
+	g_signal_connect (plugin, "ask-untrusted",
+			  G_CALLBACK (gs_plugin_loader_ask_untrusted_cb),
+			  plugin_loader);
+	gs_plugin_set_language (plugin, plugin_loader->language);
+	gs_plugin_set_scale (plugin, gs_plugin_loader_get_scale (plugin_loader));
+	gs_plugin_set_network_monitor (plugin, plugin_loader->network_monitor);
+	g_debug ("opened plugin %s: %s", filename, gs_plugin_get_name (plugin));
+
+	/* add to array */
+	g_ptr_array_add (plugin_loader->plugins, plugin);
+}
+
+static void
+gs_plugin_loader_remove_all_plugins (GsPluginLoader *plugin_loader)
+{
+	for (guint i = 0; i < plugin_loader->plugins->len; i++) {
+		GsPlugin *plugin = GS_PLUGIN (plugin_loader->plugins->pdata[i]);
+		g_signal_handlers_disconnect_by_data (plugin, plugin_loader);
+	}
+
+	g_ptr_array_set_size (plugin_loader->plugins, 0);
+}
+
+void
+gs_plugin_loader_set_scale (GsPluginLoader *plugin_loader, guint scale)
+{
+	/* save globally, and update each plugin */
+	plugin_loader->scale = scale;
+	for (guint i = 0; i < plugin_loader->plugins->len; i++) {
+		GsPlugin *plugin = g_ptr_array_index (plugin_loader->plugins, i);
+		gs_plugin_set_scale (plugin, scale);
+	}
+}
+
+guint
+gs_plugin_loader_get_scale (GsPluginLoader *plugin_loader)
+{
+	return plugin_loader->scale;
+}
+
+void
+gs_plugin_loader_add_location (GsPluginLoader *plugin_loader, const gchar *location)
+{
+	for (guint i = 0; i < plugin_loader->locations->len; i++) {
+		const gchar *location_tmp = g_ptr_array_index (plugin_loader->locations, i);
+		if (g_strcmp0 (location_tmp, location) == 0)
+			return;
+	}
+	g_info ("adding plugin location %s", location);
+	g_ptr_array_add (plugin_loader->locations, g_strdup (location));
+}
+
+static gint
+gs_plugin_loader_plugin_sort_fn (gconstpointer a, gconstpointer b)
+{
+	GsPlugin *pa = *((GsPlugin **) a);
+	GsPlugin *pb = *((GsPlugin **) b);
+	if (gs_plugin_get_order (pa) < gs_plugin_get_order (pb))
+		return -1;
+	if (gs_plugin_get_order (pa) > gs_plugin_get_order (pb))
+		return 1;
+	return g_strcmp0 (gs_plugin_get_name (pa), gs_plugin_get_name (pb));
+}
+
+static void
+gs_plugin_loader_software_app_created_cb (GObject *source_object,
+					  GAsyncResult *result,
+					  gpointer user_data)
+{
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (source_object);
+	g_autoptr(GsApp) app = NULL;
+	g_autoptr(GsPluginEvent) event = NULL;
+	g_autoptr(GError) error = NULL;
+
+	app = gs_plugin_loader_app_create_finish (plugin_loader, result, NULL);
+
+	g_set_error_literal (&error,
+			     GS_PLUGIN_ERROR,
+			     GS_PLUGIN_ERROR_RESTART_REQUIRED,
+			     "A restart is required");
+	event = gs_plugin_event_new ("action", GS_PLUGIN_ACTION_UNKNOWN,
+				     "app", app,
+				     "error", error,
+				     NULL);
+
+	gs_plugin_loader_add_event (plugin_loader, event);
+}
+
+static void
+gs_plugin_loader_plugin_dir_changed_cb (GFileMonitor *monitor,
+					GFile *file,
+					GFile *other_file,
+					GFileMonitorEvent event_type,
+					GsPluginLoader *plugin_loader)
+{
+	/* already triggered */
+	if (plugin_loader->plugin_dir_dirty)
+		return;
+
+	gs_plugin_loader_app_create_async (plugin_loader, "system/*/*/org.gnome.Software.desktop/*",
+		NULL, gs_plugin_loader_software_app_created_cb, NULL);
+
+	plugin_loader->plugin_dir_dirty = TRUE;
+}
+
+void
+gs_plugin_loader_clear_caches (GsPluginLoader *plugin_loader)
+{
+	for (guint i = 0; i < plugin_loader->plugins->len; i++) {
+		GsPlugin *plugin = g_ptr_array_index (plugin_loader->plugins, i);
+		gs_plugin_cache_invalidate (plugin);
+	}
+}
+
+static void
+gs_plugin_loader_remove_all_file_monitors (GsPluginLoader *plugin_loader)
+{
+	for (guint i = 0; i < plugin_loader->file_monitors->len; i++) {
+		GFileMonitor *file_monitor = G_FILE_MONITOR (plugin_loader->file_monitors->pdata[i]);
+
+		g_signal_handlers_disconnect_by_data (file_monitor, plugin_loader);
+		g_file_monitor_cancel (file_monitor);
+	}
+
+	g_ptr_array_set_size (plugin_loader->file_monitors, 0);
+}
+
+typedef struct {
+	GsPluginLoader *plugin_loader;  /* (unowned) */
+	GMainContext *context;  /* (owned) */
+	guint n_pending;
+} ShutdownData;
+
+static void plugin_shutdown_cb (GObject      *source_object,
+                                GAsyncResult *result,
+                                gpointer      user_data);
+
+/**
+ * gs_plugin_loader_shutdown:
+ * @plugin_loader: a #GsPluginLoader
+ * @cancellable: a #GCancellable, or %NULL
+ *
+ * Shut down the plugins.
+ *
+ * This blocks until the operation is complete. It may be refactored in future
+ * to be asynchronous.
+ *
+ * Since: 42
+ */
+void
+gs_plugin_loader_shutdown (GsPluginLoader *plugin_loader,
+                           GCancellable   *cancellable)
+{
+	ShutdownData shutdown_data;
+
+	shutdown_data.plugin_loader = plugin_loader;
+	shutdown_data.n_pending = 1;  /* incremented until all operations have been started */
+	shutdown_data.context = g_main_context_new ();
+
+	g_main_context_push_thread_default (shutdown_data.context);
+
+	for (guint i = 0; i < plugin_loader->plugins->len; i++) {
+		GsPlugin *plugin = GS_PLUGIN (plugin_loader->plugins->pdata[i]);
+
+		if (!gs_plugin_get_enabled (plugin))
+			continue;
+
+		if (GS_PLUGIN_GET_CLASS (plugin)->shutdown_async != NULL) {
+			GS_PLUGIN_GET_CLASS (plugin)->shutdown_async (plugin, cancellable,
+								      plugin_shutdown_cb, &shutdown_data);
+			shutdown_data.n_pending++;
+		}
+	}
+
+	/* Wait for shutdown to complete in all plugins. */
+	shutdown_data.n_pending--;
+
+	while (shutdown_data.n_pending > 0)
+		g_main_context_iteration (shutdown_data.context, TRUE);
+
+	g_main_context_pop_thread_default (shutdown_data.context);
+	g_clear_pointer (&shutdown_data.context, g_main_context_unref);
+
+	/* Clear some internal data structures. */
+	gs_plugin_loader_remove_all_plugins (plugin_loader);
+	gs_plugin_loader_remove_all_file_monitors (plugin_loader);
+	plugin_loader->setup_complete = FALSE;
+	g_clear_object (&plugin_loader->setup_complete_cancellable);
+	plugin_loader->setup_complete_cancellable = g_cancellable_new ();
+}
+
+static void
+plugin_shutdown_cb (GObject      *source_object,
+                    GAsyncResult *result,
+                    gpointer      user_data)
+{
+	GsPlugin *plugin = GS_PLUGIN (source_object);
+	ShutdownData *data = user_data;
+	g_autoptr(GError) local_error = NULL;
+
+	g_assert (GS_PLUGIN_GET_CLASS (plugin)->shutdown_finish != NULL);
+
+	if (!GS_PLUGIN_GET_CLASS (plugin)->shutdown_finish (plugin, result, &local_error)) {
+		g_debug ("disabling %s as shutdown failed: %s",
+			 gs_plugin_get_name (plugin),
+			 local_error->message);
+		gs_plugin_set_enabled (plugin, FALSE);
+	}
+
+	/* Indicate this plugin has finished shutting down. */
+	data->n_pending--;
+	g_main_context_wakeup (data->context);
+}
+
+static gint
+gs_plugin_loader_path_sort_fn (gconstpointer a, gconstpointer b)
+{
+	const gchar *sa = *((const gchar **) a);
+	const gchar *sb = *((const gchar **) b);
+	return g_strcmp0 (sa, sb);
+}
+
+static GPtrArray *
+gs_plugin_loader_find_plugins (const gchar *path, GError **error)
+{
+	const gchar *fn_tmp;
+	g_autoptr(GPtrArray) fns = g_ptr_array_new_with_free_func (g_free);
+	g_autoptr(GDir) dir = g_dir_open (path, 0, error);
+	if (dir == NULL)
+		return NULL;
+	while ((fn_tmp = g_dir_read_name (dir)) != NULL) {
+		if (!g_str_has_suffix (fn_tmp, ".so"))
+			continue;
+		g_ptr_array_add (fns, g_build_filename (path, fn_tmp, NULL));
+	}
+	g_ptr_array_sort (fns, gs_plugin_loader_path_sort_fn);
+	return g_steal_pointer (&fns);
+}
+
+typedef struct {
+	guint n_pending;
+	gchar **allowlist;
+	gchar **blocklist;
+#ifdef HAVE_SYSPROF
+	gint64 setup_begin_time_nsec;
+	gint64 plugins_begin_time_nsec;
+#endif
+} SetupData;
+
+static void
+setup_data_free (SetupData *data)
+{
+	g_clear_pointer (&data->allowlist, g_strfreev);
+	g_clear_pointer (&data->blocklist, g_strfreev);
+	g_free (data);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (SetupData, setup_data_free)
+
+static void get_session_bus_cb (GObject      *object,
+                                GAsyncResult *result,
+                                gpointer      user_data);
+static void get_system_bus_cb (GObject      *object,
+                               GAsyncResult *result,
+                               gpointer      user_data);
+static void finish_setup_get_bus (GTask *task);
+static void plugin_setup_cb (GObject      *source_object,
+                             GAsyncResult *result,
+                             gpointer      user_data);
+static void finish_setup_op (GTask *task);
+static void finish_setup_install_queue_cb (GObject      *source_object,
+                                           GAsyncResult *result,
+                                           gpointer      user_data);
+
+/* Mark the asynchronous setup operation as complete. This will notify any
+ * waiting tasks by cancelling the #GCancellable. It’s safe to clear the
+ * #GCancellable as each waiting task holds its own reference. */
+static void
+notify_setup_complete (GsPluginLoader *plugin_loader)
+{
+	plugin_loader->setup_complete = TRUE;
+	g_cancellable_cancel (plugin_loader->setup_complete_cancellable);
+	g_clear_object (&plugin_loader->setup_complete_cancellable);
+}
+
+/**
+ * gs_plugin_loader_setup_async:
+ * @plugin_loader: a #GsPluginLoader
+ * @allowlist: list of plugin names, or %NULL
+ * @blocklist: list of plugin names, or %NULL
+ * @cancellable: A #GCancellable, or %NULL
+ * @callback: callback to indicate completion of the asynchronous operation
+ * @user_data: data to pass to @callback
+ *
+ * Sets up the plugin loader ready for use.
+ *
+ * Since: 42
+ */
+void
+gs_plugin_loader_setup_async (GsPluginLoader      *plugin_loader,
+                              const gchar * const *allowlist,
+                              const gchar * const *blocklist,
+                              GCancellable        *cancellable,
+                              GAsyncReadyCallback  callback,
+                              gpointer             user_data)
+{
+	SetupData *setup_data;
+	g_autoptr(SetupData) setup_data_owned = NULL;
+	g_autoptr(GTask) task = NULL;
+#ifdef HAVE_SYSPROF
+	gint64 begin_time_nsec G_GNUC_UNUSED = SYSPROF_CAPTURE_CURRENT_TIME;
+#endif
+
+	task = g_task_new (plugin_loader, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_plugin_loader_setup_async);
+
+	/* If setup is already complete, return immediately. */
+	if (plugin_loader->setup_complete) {
+		g_task_return_boolean (task, TRUE);
+		return;
+	}
+
+	/* Setup data closure. */
+	setup_data = setup_data_owned = g_new0 (SetupData, 1);
+	setup_data->allowlist = g_strdupv ((gchar **) allowlist);
+	setup_data->blocklist = g_strdupv ((gchar **) blocklist);
+#ifdef HAVE_SYSPROF
+	setup_data->setup_begin_time_nsec = begin_time_nsec;
+#endif
+
+	g_task_set_task_data (task, g_steal_pointer (&setup_data_owned), (GDestroyNotify) setup_data_free);
+
+	/* Connect to D-Bus if connections haven’t been provided at construction
+	 * time. */
+	if (plugin_loader->session_bus_connection == NULL)
+		g_bus_get (G_BUS_TYPE_SESSION, cancellable, get_session_bus_cb, g_object_ref (task));
+	if (plugin_loader->system_bus_connection == NULL)
+		g_bus_get (G_BUS_TYPE_SYSTEM, cancellable, get_system_bus_cb, g_object_ref (task));
+
+	finish_setup_get_bus (task);
+}
+
+static void
+get_session_bus_cb (GObject      *object,
+                    GAsyncResult *result,
+                    gpointer      user_data)
+{
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	GsPluginLoader *plugin_loader = g_task_get_source_object (task);
+	g_autoptr(GError) local_error = NULL;
+
+	plugin_loader->session_bus_connection = g_bus_get_finish (result, &local_error);
+	if (plugin_loader->session_bus_connection == NULL) {
+		notify_setup_complete (plugin_loader);
+		g_prefix_error_literal (&local_error, "Error getting session bus: ");
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	g_object_notify_by_pspec (G_OBJECT (plugin_loader), obj_props[PROP_SESSION_BUS_CONNECTION]);
+
+	finish_setup_get_bus (task);
+}
+
+static void
+get_system_bus_cb (GObject      *object,
+                   GAsyncResult *result,
+                   gpointer      user_data)
+{
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	GsPluginLoader *plugin_loader = g_task_get_source_object (task);
+	g_autoptr(GError) local_error = NULL;
+
+	plugin_loader->system_bus_connection = g_bus_get_finish (result, &local_error);
+	if (plugin_loader->system_bus_connection == NULL) {
+		notify_setup_complete (plugin_loader);
+		g_prefix_error_literal (&local_error, "Error getting system bus: ");
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	g_object_notify_by_pspec (G_OBJECT (plugin_loader), obj_props[PROP_SYSTEM_BUS_CONNECTION]);
+
+	finish_setup_get_bus (task);
+}
+
+static void
+finish_setup_get_bus (GTask *task)
+{
+	SetupData *data = g_task_get_task_data (task);
+	GsPluginLoader *plugin_loader = g_task_get_source_object (task);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+	const gchar *plugin_name;
+	gboolean changes;
+	GPtrArray *deps;
+	GsPlugin *dep;
+	GsPlugin *plugin;
+	guint dep_loop_check = 0;
+	guint i;
+	guint j;
+	g_autoptr(GPtrArray) locations = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	/* Wait until we’ve got all the buses we need. */
+	if (plugin_loader->session_bus_connection == NULL ||
+	    plugin_loader->system_bus_connection == NULL)
+		return;
+
+	/* use the default, but this requires a 'make install' */
+	if (plugin_loader->locations->len == 0) {
+		g_autofree gchar *filename = NULL;
+		filename = g_strdup_printf ("plugins-%s", GS_PLUGIN_API_VERSION);
+		locations = g_ptr_array_new_with_free_func (g_free);
+		g_ptr_array_add (locations, g_build_filename (LIBDIR, "gnome-software", filename, NULL));
+	} else {
+		locations = g_ptr_array_ref (plugin_loader->locations);
+	}
+
+	for (i = 0; i < locations->len; i++) {
+		GFileMonitor *monitor;
+		const gchar *location = g_ptr_array_index (locations, i);
+		g_autoptr(GFile) plugin_dir = g_file_new_for_path (location);
+		g_debug ("monitoring plugin location %s", location);
+		monitor = g_file_monitor_directory (plugin_dir,
+						    G_FILE_MONITOR_NONE,
+						    cancellable,
+						    &local_error);
+		if (monitor == NULL) {
+			notify_setup_complete (plugin_loader);
+			g_task_return_error (task, g_steal_pointer (&local_error));
+			return;
+		}
+
+		g_signal_connect (monitor, "changed",
+				  G_CALLBACK (gs_plugin_loader_plugin_dir_changed_cb), plugin_loader);
+		g_ptr_array_add (plugin_loader->file_monitors, monitor);
+	}
+
+	/* search for plugins */
+	for (i = 0; i < locations->len; i++) {
+		const gchar *location = g_ptr_array_index (locations, i);
+		g_autoptr(GPtrArray) fns = NULL;
+
+		/* search in the plugin directory for plugins */
+		g_debug ("searching for plugins in %s", location);
+		fns = gs_plugin_loader_find_plugins (location, &local_error);
+		if (fns == NULL) {
+			notify_setup_complete (plugin_loader);
+			g_task_return_error (task, g_steal_pointer (&local_error));
+			return;
+		}
+
+		for (j = 0; j < fns->len; j++) {
+			const gchar *fn = g_ptr_array_index (fns, j);
+			gs_plugin_loader_open_plugin (plugin_loader, fn);
+		}
+	}
+
+	/* optional allowlist */
+	if (data->allowlist != NULL) {
+		for (i = 0; i < plugin_loader->plugins->len; i++) {
+			gboolean ret;
+			plugin = g_ptr_array_index (plugin_loader->plugins, i);
+			if (!gs_plugin_get_enabled (plugin))
+				continue;
+			ret = g_strv_contains ((const gchar * const *) data->allowlist,
+					       gs_plugin_get_name (plugin));
+			if (!ret) {
+				g_debug ("%s not in allowlist, disabling",
+					 gs_plugin_get_name (plugin));
+			}
+			gs_plugin_set_enabled (plugin, ret);
+		}
+	}
+
+	/* optional blocklist */
+	if (data->blocklist != NULL) {
+		for (i = 0; i < plugin_loader->plugins->len; i++) {
+			gboolean ret;
+			plugin = g_ptr_array_index (plugin_loader->plugins, i);
+			if (!gs_plugin_get_enabled (plugin))
+				continue;
+			ret = g_strv_contains ((const gchar * const *) data->blocklist,
+					       gs_plugin_get_name (plugin));
+			if (ret)
+				gs_plugin_set_enabled (plugin, FALSE);
+		}
+	}
+
+	/* order by deps */
+	do {
+		changes = FALSE;
+		for (i = 0; i < plugin_loader->plugins->len; i++) {
+			plugin = g_ptr_array_index (plugin_loader->plugins, i);
+			deps = gs_plugin_get_rules (plugin, GS_PLUGIN_RULE_RUN_AFTER);
+			for (j = 0; j < deps->len && !changes; j++) {
+				plugin_name = g_ptr_array_index (deps, j);
+				dep = gs_plugin_loader_find_plugin (plugin_loader,
+								    plugin_name);
+				if (dep == NULL) {
+					g_debug ("cannot find plugin '%s' "
+						 "requested by '%s'",
+						 plugin_name,
+						 gs_plugin_get_name (plugin));
+					continue;
+				}
+				if (!gs_plugin_get_enabled (dep))
+					continue;
+				if (gs_plugin_get_order (plugin) <= gs_plugin_get_order (dep)) {
+					gs_plugin_set_order (plugin, gs_plugin_get_order (dep) + 1);
+					changes = TRUE;
+				}
+			}
+		}
+		for (i = 0; i < plugin_loader->plugins->len; i++) {
+			plugin = g_ptr_array_index (plugin_loader->plugins, i);
+			deps = gs_plugin_get_rules (plugin, GS_PLUGIN_RULE_RUN_BEFORE);
+			for (j = 0; j < deps->len && !changes; j++) {
+				plugin_name = g_ptr_array_index (deps, j);
+				dep = gs_plugin_loader_find_plugin (plugin_loader,
+								    plugin_name);
+				if (dep == NULL) {
+					g_debug ("cannot find plugin '%s' "
+						 "requested by '%s'",
+						 plugin_name,
+						 gs_plugin_get_name (plugin));
+					continue;
+				}
+				if (!gs_plugin_get_enabled (dep))
+					continue;
+				if (gs_plugin_get_order (plugin) >= gs_plugin_get_order (dep)) {
+					gs_plugin_set_order (dep, gs_plugin_get_order (plugin) + 1);
+					changes = TRUE;
+				}
+			}
+		}
+
+		/* check we're not stuck */
+		if (dep_loop_check++ > 100) {
+			notify_setup_complete (plugin_loader);
+			g_task_return_new_error (task,
+						 GS_PLUGIN_ERROR,
+						 GS_PLUGIN_ERROR_PLUGIN_DEPSOLVE_FAILED,
+						 "got stuck in dep loop");
+			return;
+		}
+	} while (changes);
+
+	/* check for conflicts */
+	for (i = 0; i < plugin_loader->plugins->len; i++) {
+		plugin = g_ptr_array_index (plugin_loader->plugins, i);
+		if (!gs_plugin_get_enabled (plugin))
+			continue;
+		deps = gs_plugin_get_rules (plugin, GS_PLUGIN_RULE_CONFLICTS);
+		for (j = 0; j < deps->len && !changes; j++) {
+			plugin_name = g_ptr_array_index (deps, j);
+			dep = gs_plugin_loader_find_plugin (plugin_loader,
+							    plugin_name);
+			if (dep == NULL)
+				continue;
+			if (!gs_plugin_get_enabled (dep))
+				continue;
+			g_debug ("disabling %s as conflicts with %s",
+				 gs_plugin_get_name (dep),
+				 gs_plugin_get_name (plugin));
+			gs_plugin_set_enabled (dep, FALSE);
+		}
+	}
+
+	/* sort by order */
+	g_ptr_array_sort (plugin_loader->plugins,
+			  gs_plugin_loader_plugin_sort_fn);
+
+	/* assign priority values */
+	do {
+		changes = FALSE;
+		for (i = 0; i < plugin_loader->plugins->len; i++) {
+			plugin = g_ptr_array_index (plugin_loader->plugins, i);
+			deps = gs_plugin_get_rules (plugin, GS_PLUGIN_RULE_BETTER_THAN);
+			for (j = 0; j < deps->len && !changes; j++) {
+				plugin_name = g_ptr_array_index (deps, j);
+				dep = gs_plugin_loader_find_plugin (plugin_loader,
+								    plugin_name);
+				if (dep == NULL) {
+					g_debug ("cannot find plugin '%s' "
+						 "requested by '%s'",
+						 plugin_name,
+						 gs_plugin_get_name (plugin));
+					continue;
+				}
+				if (!gs_plugin_get_enabled (dep))
+					continue;
+				if (gs_plugin_get_priority (plugin) <= gs_plugin_get_priority (dep)) {
+					gs_plugin_set_priority (plugin, gs_plugin_get_priority (dep) + 1);
+					changes = TRUE;
+				}
+			}
+		}
+
+		/* check we're not stuck */
+		if (dep_loop_check++ > 100) {
+			notify_setup_complete (plugin_loader);
+			g_task_return_new_error (task,
+						 GS_PLUGIN_ERROR,
+						 GS_PLUGIN_ERROR_PLUGIN_DEPSOLVE_FAILED,
+						 "got stuck in priority loop");
+			return;
+		}
+	} while (changes);
+
+	/* run setup */
+	data->n_pending = 1;  /* incremented until all operations have been started */
+#ifdef HAVE_SYSPROF
+	data->plugins_begin_time_nsec = SYSPROF_CAPTURE_CURRENT_TIME;
+#endif
+
+	for (i = 0; i < plugin_loader->plugins->len; i++) {
+		plugin = GS_PLUGIN (plugin_loader->plugins->pdata[i]);
+
+		if (!gs_plugin_get_enabled (plugin))
+			continue;
+
+		if (GS_PLUGIN_GET_CLASS (plugin)->setup_async != NULL) {
+			data->n_pending++;
+			GS_PLUGIN_GET_CLASS (plugin)->setup_async (plugin, cancellable,
+								   plugin_setup_cb, g_object_ref (task));
+		}
+	}
+
+	finish_setup_op (task);
+}
+
+static void
+plugin_setup_cb (GObject      *source_object,
+                 GAsyncResult *result,
+                 gpointer      user_data)
+{
+	GsPlugin *plugin = GS_PLUGIN (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	g_autoptr(GError) local_error = NULL;
+#ifdef HAVE_SYSPROF
+	GsPluginLoader *plugin_loader = g_task_get_source_object (task);
+	SetupData *data = g_task_get_task_data (task);
+#endif /* HAVE_SYSPROF */
+
+	g_assert (GS_PLUGIN_GET_CLASS (plugin)->setup_finish != NULL);
+
+	if (!GS_PLUGIN_GET_CLASS (plugin)->setup_finish (plugin, result, &local_error)) {
+		g_debug ("disabling %s as setup failed: %s",
+			 gs_plugin_get_name (plugin),
+			 local_error->message);
+		gs_plugin_set_enabled (plugin, FALSE);
+	}
+
+#ifdef HAVE_SYSPROF
+	if (plugin_loader->sysprof_writer != NULL) {
+		sysprof_capture_writer_add_mark (plugin_loader->sysprof_writer,
+						 data->plugins_begin_time_nsec,
+						 sched_getcpu (),
+						 getpid (),
+						 SYSPROF_CAPTURE_CURRENT_TIME - data->plugins_begin_time_nsec,
+						 "gnome-software",
+						 "setup-plugin",
+						 NULL);
+	}
+#endif  /* HAVE_SYSPROF */
+
+	/* Indicate this plugin has finished setting up. */
+	finish_setup_op (task);
+}
+
+static void
+finish_setup_op (GTask *task)
+{
+	SetupData *data = g_task_get_task_data (task);
+	GsPluginLoader *plugin_loader = g_task_get_source_object (task);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+	g_autoptr(GsAppList) install_queue = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	g_assert (data->n_pending > 0);
+	data->n_pending--;
+
+	if (data->n_pending > 0)
+		return;
+
+	/* now we can load the install-queue */
+	install_queue = load_install_queue (plugin_loader, &local_error);
+	if (install_queue == NULL) {
+		notify_setup_complete (plugin_loader);
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	/* Mark setup as complete as it’s now safe for other jobs to be
+	 * processed. Indeed, the final step in setup is to refine the install
+	 * queue apps, which requires @setup_complete to be %TRUE. */
+	notify_setup_complete (plugin_loader);
+
+#ifdef HAVE_SYSPROF
+	if (plugin_loader->sysprof_writer != NULL) {
+		sysprof_capture_writer_add_mark (plugin_loader->sysprof_writer,
+						 data->setup_begin_time_nsec,
+						 sched_getcpu (),
+						 getpid (),
+						 SYSPROF_CAPTURE_CURRENT_TIME - data->setup_begin_time_nsec,
+						 "gnome-software",
+						 "setup",
+						 NULL);
+	}
+#endif  /* HAVE_SYSPROF */
+
+	/* Refine the install queue. */
+	if (gs_app_list_length (install_queue) > 0) {
+		g_autoptr(GsPluginJob) refine_job = NULL;
+
+		/* Require ID and Origin to get complete unique IDs */
+		refine_job = gs_plugin_job_refine_new (install_queue, GS_PLUGIN_REFINE_FLAGS_REQUIRE_ID |
+								      GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN |
+								      GS_PLUGIN_REFINE_FLAGS_DISABLE_FILTERING);
+		gs_plugin_loader_job_process_async (plugin_loader, refine_job,
+						    cancellable,
+						    finish_setup_install_queue_cb,
+						    g_object_ref (task));
+	} else {
+		g_task_return_boolean (task, TRUE);
+	}
+}
+
+static void gs_plugin_loader_maybe_flush_pending_install_queue (GsPluginLoader *plugin_loader);
+
+static void
+finish_setup_install_queue_cb (GObject      *source_object,
+                               GAsyncResult *result,
+                               gpointer      user_data)
+{
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (source_object);
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	g_autoptr(GsAppList) new_list = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	new_list = gs_plugin_loader_job_process_finish (plugin_loader, result, &local_error);
+	if (new_list == NULL) {
+		g_task_return_error (task, g_steal_pointer (&local_error));
+	} else {
+		g_autoptr(GsAppList) old_pending_apps = NULL;
+		gboolean has_pending_apps = FALSE;
+		gboolean changed;
+		g_mutex_lock (&plugin_loader->pending_apps_mutex);
+		changed = plugin_loader->pending_apps != NULL;
+		/* Merge the existing and newly-loaded lists, in case pending apps were added
+		   while the install-queue file was being loaded */
+		old_pending_apps = g_steal_pointer (&plugin_loader->pending_apps);
+		if (old_pending_apps != NULL && gs_app_list_length (new_list) > 0) {
+			g_autoptr(GHashTable) expected_unique_ids = g_hash_table_new (g_str_hash, g_str_equal);
+			for (guint i = 0; i < gs_app_list_length (old_pending_apps); i++) {
+				GsApp *app = gs_app_list_index (old_pending_apps, i);
+				if (gs_app_get_unique_id (app) != NULL)
+					g_hash_table_add (expected_unique_ids, (gpointer) gs_app_get_unique_id (app));
+			}
+			for (guint i = 0; i < gs_app_list_length (new_list); i++) {
+				GsApp *app = gs_app_list_index (new_list, i);
+				if (gs_app_get_state (app) == GS_APP_STATE_AVAILABLE &&
+				    gs_app_get_unique_id (app) != NULL &&
+				    g_hash_table_contains (expected_unique_ids, gs_app_get_unique_id (app))) {
+					if (plugin_loader->pending_apps == NULL)
+						plugin_loader->pending_apps = gs_app_list_new ();
+					gs_app_set_state (app, GS_APP_STATE_QUEUED_FOR_INSTALL);
+					gs_app_set_pending_action (app, GS_PLUGIN_ACTION_INSTALL);
+					gs_app_list_add (plugin_loader->pending_apps, app);
+				}
+			}
+			has_pending_apps = plugin_loader->pending_apps != NULL;
+			changed = TRUE;
+		}
+		g_mutex_unlock (&plugin_loader->pending_apps_mutex);
+		g_task_return_boolean (task, TRUE);
+
+		if (changed)
+			save_install_queue (plugin_loader);
+		if (has_pending_apps)
+			gs_plugin_loader_maybe_flush_pending_install_queue (plugin_loader);
+	}
+}
+
+/**
+ * gs_plugin_loader_setup_finish:
+ * @plugin_loader: a #GsPluginLoader
+ * @result: result of the asynchronous operation
+ * @error: return location for a #GError, or %NULL
+ *
+ * Finish an asynchronous setup operation started with
+ * gs_plugin_loader_setup_async().
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 42
+ */
+gboolean
+gs_plugin_loader_setup_finish (GsPluginLoader  *plugin_loader,
+                               GAsyncResult    *result,
+                               GError         **error)
+{
+	g_return_val_if_fail (GS_IS_PLUGIN_LOADER (plugin_loader), FALSE);
+	g_return_val_if_fail (g_task_is_valid (result, plugin_loader), FALSE);
+	g_return_val_if_fail (g_async_result_is_tagged (result, gs_plugin_loader_setup_async), FALSE);
+
+	return g_task_propagate_boolean (G_TASK (result), error);
+}
+
+void
+gs_plugin_loader_dump_state (GsPluginLoader *plugin_loader)
+{
+	g_autoptr(GString) str_enabled = g_string_new (NULL);
+	g_autoptr(GString) str_disabled = g_string_new (NULL);
+
+	/* print what the priorities are if verbose */
+	for (guint i = 0; i < plugin_loader->plugins->len; i++) {
+		GsPlugin *plugin = g_ptr_array_index (plugin_loader->plugins, i);
+		GString *str = gs_plugin_get_enabled (plugin) ? str_enabled : str_disabled;
+		g_string_append_printf (str, "%s, ", gs_plugin_get_name (plugin));
+		g_debug ("[%s]\t%u\t->\t%s",
+			 gs_plugin_get_enabled (plugin) ? "enabled" : "disabld",
+			 gs_plugin_get_order (plugin),
+			 gs_plugin_get_name (plugin));
+	}
+	if (str_enabled->len > 2)
+		g_string_truncate (str_enabled, str_enabled->len - 2);
+	if (str_disabled->len > 2)
+		g_string_truncate (str_disabled, str_disabled->len - 2);
+	g_info ("enabled plugins: %s", str_enabled->str);
+	g_info ("disabled plugins: %s", str_disabled->str);
+}
+
+static void
+gs_plugin_loader_get_property (GObject *object, guint prop_id,
+			       GValue *value, GParamSpec *pspec)
+{
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (object);
+
+	switch ((GsPluginLoaderProperty) prop_id) {
+	case PROP_EVENTS:
+		g_value_set_pointer (value, plugin_loader->events_by_id);
+		break;
+	case PROP_ALLOW_UPDATES:
+		g_value_set_boolean (value, gs_plugin_loader_get_allow_updates (plugin_loader));
+		break;
+	case PROP_NETWORK_AVAILABLE:
+		g_value_set_boolean (value, gs_plugin_loader_get_network_available (plugin_loader));
+		break;
+	case PROP_NETWORK_METERED:
+		g_value_set_boolean (value, gs_plugin_loader_get_network_metered (plugin_loader));
+		break;
+	case PROP_SESSION_BUS_CONNECTION:
+		g_value_set_object (value, plugin_loader->session_bus_connection);
+		break;
+	case PROP_SYSTEM_BUS_CONNECTION:
+		g_value_set_object (value, plugin_loader->system_bus_connection);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_plugin_loader_set_property (GObject *object, guint prop_id,
+			       const GValue *value, GParamSpec *pspec)
+{
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (object);
+
+	switch ((GsPluginLoaderProperty) prop_id) {
+	case PROP_EVENTS:
+	case PROP_ALLOW_UPDATES:
+	case PROP_NETWORK_AVAILABLE:
+	case PROP_NETWORK_METERED:
+		/* Read only */
+		g_assert_not_reached ();
+		break;
+	case PROP_SESSION_BUS_CONNECTION:
+		/* Construct only */
+		g_assert (plugin_loader->session_bus_connection == NULL);
+		plugin_loader->session_bus_connection = g_value_dup_object (value);
+		break;
+	case PROP_SYSTEM_BUS_CONNECTION:
+		/* Construct only */
+		g_assert (plugin_loader->system_bus_connection == NULL);
+		plugin_loader->system_bus_connection = g_value_dup_object (value);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_plugin_loader_dispose (GObject *object)
+{
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (object);
+
+	g_cancellable_cancel (plugin_loader->pending_apps_cancellable);
+
+	if (plugin_loader->plugins != NULL) {
+		/* Shut down all the plugins first. */
+		gs_plugin_loader_shutdown (plugin_loader, NULL);
+
+		g_clear_pointer (&plugin_loader->plugins, g_ptr_array_unref);
+	}
+	if (plugin_loader->updates_changed_id != 0) {
+		g_source_remove (plugin_loader->updates_changed_id);
+		plugin_loader->updates_changed_id = 0;
+	}
+	if (plugin_loader->network_changed_handler != 0) {
+		g_signal_handler_disconnect (plugin_loader->network_monitor,
+					     plugin_loader->network_changed_handler);
+		plugin_loader->network_changed_handler = 0;
+	}
+	if (plugin_loader->network_available_notify_handler != 0) {
+		g_signal_handler_disconnect (plugin_loader->network_monitor,
+					     plugin_loader->network_available_notify_handler);
+		plugin_loader->network_available_notify_handler = 0;
+	}
+	if (plugin_loader->network_metered_notify_handler != 0) {
+		g_signal_handler_disconnect (plugin_loader->network_monitor,
+					     plugin_loader->network_metered_notify_handler);
+		plugin_loader->network_metered_notify_handler = 0;
+	}
+	if (plugin_loader->queued_ops_pool != NULL) {
+		/* stop accepting more requests and wait until any currently
+		 * running ones are finished */
+		g_thread_pool_free (plugin_loader->queued_ops_pool, TRUE, TRUE);
+		plugin_loader->queued_ops_pool = NULL;
+	}
+	g_clear_object (&plugin_loader->network_monitor);
+	g_clear_object (&plugin_loader->settings);
+	g_clear_object (&plugin_loader->pending_apps);
+	g_clear_object (&plugin_loader->category_manager);
+	g_clear_object (&plugin_loader->odrs_provider);
+	g_clear_object (&plugin_loader->setup_complete_cancellable);
+	g_clear_object (&plugin_loader->pending_apps_cancellable);
+
+#ifdef HAVE_SYSPROF
+	g_clear_pointer (&plugin_loader->sysprof_writer, sysprof_capture_writer_unref);
+#endif
+
+	g_clear_object (&plugin_loader->session_bus_connection);
+	g_clear_object (&plugin_loader->system_bus_connection);
+
+	G_OBJECT_CLASS (gs_plugin_loader_parent_class)->dispose (object);
+}
+
+static void
+gs_plugin_loader_finalize (GObject *object)
+{
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (object);
+
+	g_strfreev (plugin_loader->compatible_projects);
+	g_ptr_array_unref (plugin_loader->locations);
+	g_free (plugin_loader->language);
+	g_ptr_array_unref (plugin_loader->file_monitors);
+	g_hash_table_unref (plugin_loader->events_by_id);
+	g_hash_table_unref (plugin_loader->disallow_updates);
+
+	g_mutex_clear (&plugin_loader->pending_apps_mutex);
+	g_mutex_clear (&plugin_loader->events_by_id_mutex);
+
+	G_OBJECT_CLASS (gs_plugin_loader_parent_class)->finalize (object);
+}
+
+static void
+gs_plugin_loader_class_init (GsPluginLoaderClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+	object_class->get_property = gs_plugin_loader_get_property;
+	object_class->set_property = gs_plugin_loader_set_property;
+	object_class->dispose = gs_plugin_loader_dispose;
+	object_class->finalize = gs_plugin_loader_finalize;
+
+	/**
+	 * GsPluginLoader:events:
+	 *
+	 * Events added on the plugin loader using gs_plugin_loader_add_event().
+	 */
+	obj_props[PROP_EVENTS] =
+		g_param_spec_string ("events", NULL, NULL,
+				     NULL,
+				     G_PARAM_READABLE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPluginLoader:allow-updates:
+	 *
+	 * Whether updates and upgrades are managed by gnome-software.
+	 *
+	 * If not, the updates UI should be hidden and no automatic updates
+	 * performed.
+	 */
+	obj_props[PROP_ALLOW_UPDATES] =
+		g_param_spec_boolean ("allow-updates", NULL, NULL,
+				      TRUE,
+				      G_PARAM_READABLE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPluginLoader:network-available:
+	 *
+	 * Whether the network is considered available.
+	 *
+	 * This has the same semantics as #GNetworkMonitor:network-available.
+	 */
+	obj_props[PROP_NETWORK_AVAILABLE] =
+		g_param_spec_boolean ("network-available", NULL, NULL,
+				      FALSE,
+				      G_PARAM_READABLE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPluginLoader:network-metered:
+	 *
+	 * Whether the network is considered metered.
+	 *
+	 * This has the same semantics as #GNetworkMonitor:network-metered.
+	 */
+	obj_props[PROP_NETWORK_METERED] =
+		g_param_spec_boolean ("network-metered", NULL, NULL,
+				      FALSE,
+				      G_PARAM_READABLE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPluginLoader:session-bus-connection: (nullable)
+	 *
+	 * A connection to the D-Bus session bus.
+	 *
+	 * This may be %NULL at construction time. If so, the default session
+	 * bus connection will be used (and returned as the value of this
+	 * property) after gs_plugin_loader_setup_async() is called.
+	 *
+	 * Since: 43
+	 */
+	obj_props[PROP_SESSION_BUS_CONNECTION] =
+		g_param_spec_object ("session-bus-connection", NULL, NULL,
+				     G_TYPE_DBUS_CONNECTION,
+				     G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPluginLoader:system-bus-connection: (not nullable)
+	 *
+	 * A connection to the D-Bus system bus.
+	 *
+	 * This may be %NULL at construction time. If so, the default system
+	 * bus connection will be used (and returned as the value of this
+	 * property) after gs_plugin_loader_setup_async() is called.
+	 *
+	 * Since: 43
+	 */
+	obj_props[PROP_SYSTEM_BUS_CONNECTION] =
+		g_param_spec_object ("system-bus-connection", NULL, NULL,
+				     G_TYPE_DBUS_CONNECTION,
+				     G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	g_object_class_install_properties (object_class, G_N_ELEMENTS (obj_props), obj_props);
+
+	signals [SIGNAL_STATUS_CHANGED] =
+		g_signal_new ("status-changed",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      0, NULL, NULL, g_cclosure_marshal_generic,
+			      G_TYPE_NONE, 2, G_TYPE_POINTER, G_TYPE_UINT);
+	signals [SIGNAL_PENDING_APPS_CHANGED] =
+		g_signal_new ("pending-apps-changed",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      0, NULL, NULL, g_cclosure_marshal_VOID__VOID,
+			      G_TYPE_NONE, 0);
+	signals [SIGNAL_UPDATES_CHANGED] =
+		g_signal_new ("updates-changed",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      0, NULL, NULL, g_cclosure_marshal_VOID__VOID,
+			      G_TYPE_NONE, 0);
+	signals [SIGNAL_RELOAD] =
+		g_signal_new ("reload",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      0, NULL, NULL, g_cclosure_marshal_VOID__VOID,
+			      G_TYPE_NONE, 0);
+	signals [SIGNAL_BASIC_AUTH_START] =
+		g_signal_new ("basic-auth-start",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      0, NULL, NULL, g_cclosure_marshal_generic,
+			      G_TYPE_NONE, 4, G_TYPE_STRING, G_TYPE_STRING, G_TYPE_POINTER, G_TYPE_POINTER);
+	signals [SIGNAL_ASK_UNTRUSTED] =
+		g_signal_new ("ask-untrusted",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      0, NULL, NULL, g_cclosure_marshal_generic,
+			      G_TYPE_BOOLEAN, 4, G_TYPE_STRING, G_TYPE_STRING, G_TYPE_STRING, G_TYPE_STRING);
+}
+
+static void
+gs_plugin_loader_allow_updates_recheck (GsPluginLoader *plugin_loader)
+{
+	if (g_settings_get_boolean (plugin_loader->settings, "allow-updates")) {
+		g_hash_table_remove (plugin_loader->disallow_updates, plugin_loader);
+	} else {
+		g_hash_table_insert (plugin_loader->disallow_updates,
+				     (gpointer) plugin_loader,
+				     (gpointer) "GSettings");
+	}
+}
+
+static void
+gs_plugin_loader_settings_changed_cb (GSettings *settings,
+				      const gchar *key,
+				      GsPluginLoader *plugin_loader)
+{
+	if (g_strcmp0 (key, "allow-updates") == 0)
+		gs_plugin_loader_allow_updates_recheck (plugin_loader);
+}
+
+static gint
+get_max_parallel_ops (void)
+{
+	guint mem_total = gs_utils_get_memory_total ();
+	if (mem_total == 0)
+		return 8;
+	/* allow 1 op per GB of memory */
+	return (gint) MAX (round((gdouble) mem_total / 1024), 1.0);
+}
+
+static void
+gs_plugin_loader_init (GsPluginLoader *plugin_loader)
+{
+	const gchar *tmp;
+	gchar *match;
+	gchar **projects;
+	guint i;
+	g_autofree gchar *review_server = NULL;
+	g_autofree gchar *user_hash = NULL;
+	g_autoptr(GError) local_error = NULL;
+	const guint64 odrs_review_max_cache_age_secs = 237000;  /* 1 week */
+	const guint odrs_review_n_results_max = 20;
+	const gchar *locale;
+
+#ifdef HAVE_SYSPROF
+	plugin_loader->sysprof_writer = sysprof_capture_writer_new_from_env (0);
+#endif  /* HAVE_SYSPROF */
+
+	plugin_loader->setup_complete_cancellable = g_cancellable_new ();
+	plugin_loader->scale = 1;
+	plugin_loader->plugins = g_ptr_array_new_with_free_func (g_object_unref);
+	plugin_loader->pending_apps = NULL;
+	plugin_loader->queued_ops_pool = g_thread_pool_new (gs_plugin_loader_process_in_thread_pool_cb,
+						   NULL,
+						   get_max_parallel_ops (),
+						   FALSE,
+						   NULL);
+	plugin_loader->file_monitors = g_ptr_array_new_with_free_func (g_object_unref);
+	plugin_loader->locations = g_ptr_array_new_with_free_func (g_free);
+	plugin_loader->settings = g_settings_new ("org.gnome.software");
+	g_signal_connect (plugin_loader->settings, "changed",
+			  G_CALLBACK (gs_plugin_loader_settings_changed_cb), plugin_loader);
+	plugin_loader->events_by_id = g_hash_table_new_full ((GHashFunc) as_utils_data_id_hash,
+							     (GEqualFunc) as_utils_data_id_equal,
+							     g_free,
+							     (GDestroyNotify) g_object_unref);
+
+	/* get the category manager */
+	plugin_loader->category_manager = gs_category_manager_new ();
+
+	/* set up the ODRS provider */
+
+	/* get the machine+user ID hash value */
+	user_hash = gs_utils_get_user_hash (&local_error);
+	if (user_hash == NULL) {
+		g_warning ("Failed to get machine+user hash: %s", local_error->message);
+		plugin_loader->odrs_provider = NULL;
+	} else {
+		review_server = g_settings_get_string (plugin_loader->settings, "review-server");
+
+		if (review_server != NULL && *review_server != '\0') {
+			const gchar *distro = NULL;
+			g_autoptr(GsOsRelease) os_release = NULL;
+			g_autoptr(SoupSession) odrs_soup_session = NULL;
+
+			/* get the distro name (e.g. 'Fedora') but allow a fallback */
+			os_release = gs_os_release_new (&local_error);
+			if (os_release != NULL) {
+				distro = gs_os_release_get_name (os_release);
+				if (distro == NULL)
+					g_warning ("no distro name specified");
+			} else {
+				g_warning ("failed to get distro name: %s", local_error->message);
+			}
+
+			/* Fallback */
+			if (distro == NULL)
+				distro = C_("Distribution name", "Unknown");
+
+			odrs_soup_session = gs_build_soup_session ();
+			plugin_loader->odrs_provider = gs_odrs_provider_new (review_server,
+									     user_hash,
+									     distro,
+									     odrs_review_max_cache_age_secs,
+									     odrs_review_n_results_max,
+									     odrs_soup_session);
+		}
+	}
+
+	/* the settings key sets the initial override */
+	plugin_loader->disallow_updates = g_hash_table_new (g_direct_hash, g_direct_equal);
+	gs_plugin_loader_allow_updates_recheck (plugin_loader);
+
+	/* get the language from the locale (i.e. strip the territory, codeset
+	 * and modifier) */
+	locale = setlocale (LC_MESSAGES, NULL);
+	plugin_loader->language = g_strdup (locale);
+	match = strpbrk (plugin_loader->language, "._@");
+	if (match != NULL)
+		*match = '\0';
+
+	g_debug ("Using locale = %s, language = %s", locale, plugin_loader->language);
+
+	g_mutex_init (&plugin_loader->pending_apps_mutex);
+	g_mutex_init (&plugin_loader->events_by_id_mutex);
+
+	/* monitor the network as the many UI operations need the network */
+	gs_plugin_loader_monitor_network (plugin_loader);
+
+	/* by default we only show project-less apps or compatible projects */
+	tmp = g_getenv ("GNOME_SOFTWARE_COMPATIBLE_PROJECTS");
+	if (tmp == NULL) {
+		projects = g_settings_get_strv (plugin_loader->settings,
+						"compatible-projects");
+	} else {
+		projects = g_strsplit (tmp, ",", -1);
+	}
+	for (i = 0; projects[i] != NULL; i++)
+		g_debug ("compatible-project: %s", projects[i]);
+	plugin_loader->compatible_projects = projects;
+}
+
+/**
+ * gs_plugin_loader_new:
+ * @session_bus_connection: (nullable) (transfer none): a D-Bus session bus
+ *   connection to use, or %NULL to use the default
+ * @system_bus_connection: (nullable) (transfer none): a D-Bus system bus
+ *   connection to use, or %NULL to use the default
+ *
+ * Create a new #GsPluginLoader.
+ *
+ * The D-Bus connection arguments should typically be %NULL, and only be
+ * non-%NULL when doing unit tests.
+ *
+ * Return value: (transfer full) (not nullable): a new #GsPluginLoader
+ * Since: 43
+ **/
+GsPluginLoader *
+gs_plugin_loader_new (GDBusConnection *session_bus_connection,
+                      GDBusConnection *system_bus_connection)
+{
+	g_return_val_if_fail (session_bus_connection == NULL || G_IS_DBUS_CONNECTION (session_bus_connection), NULL);
+	g_return_val_if_fail (system_bus_connection == NULL || G_IS_DBUS_CONNECTION (system_bus_connection), NULL);
+
+	return g_object_new (GS_TYPE_PLUGIN_LOADER,
+			     "session-bus-connection", session_bus_connection,
+			     "system-bus-connection", system_bus_connection,
+			     NULL);
+}
+
+static void
+gs_plugin_loader_app_installed_cb (GObject *source,
+				   GAsyncResult *res,
+				   gpointer user_data)
+{
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (source);
+	gboolean ret;
+	g_autoptr(GError) error = NULL;
+	g_autoptr(GsApp) app = GS_APP (user_data);
+
+	ret = gs_plugin_loader_job_action_finish (plugin_loader,
+						   res,
+						   &error);
+	remove_app_from_install_queue (plugin_loader, app);
+	if (!ret) {
+		gs_app_set_state_recover (app);
+		g_warning ("failed to install %s: %s",
+			   gs_app_get_unique_id (app), error->message);
+	}
+}
+
+gboolean
+gs_plugin_loader_get_network_available (GsPluginLoader *plugin_loader)
+{
+	if (plugin_loader->network_monitor == NULL) {
+		g_debug ("no network monitor, so returning network-available=TRUE");
+		return TRUE;
+	}
+	return g_network_monitor_get_network_available (plugin_loader->network_monitor);
+}
+
+gboolean
+gs_plugin_loader_get_network_metered (GsPluginLoader *plugin_loader)
+{
+	if (plugin_loader->network_monitor == NULL) {
+		g_debug ("no network monitor, so returning network-metered=FALSE");
+		return FALSE;
+	}
+	return g_network_monitor_get_network_metered (plugin_loader->network_monitor);
+}
+
+static void
+gs_plugin_loader_pending_apps_refined_cb (GObject      *source,
+                                          GAsyncResult *res,
+                                          gpointer      user_data)
+{
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (source);
+	g_autoptr(GsAppList) old_queue = GS_APP_LIST (user_data);
+	g_autoptr(GsAppList) refined_queue = NULL;
+	g_autoptr(GError) error = NULL;
+
+	refined_queue = gs_plugin_loader_job_process_finish (plugin_loader, res, &error);
+
+	if (refined_queue == NULL) {
+		if (!g_error_matches (error, G_IO_ERROR, G_IO_ERROR_CANCELLED) &&
+		    !g_error_matches (error, GS_PLUGIN_ERROR, GS_PLUGIN_ERROR_CANCELLED)) {
+			g_debug ("failed to refine pending apps: %s", error->message);
+
+			g_mutex_lock (&plugin_loader->pending_apps_mutex);
+			g_clear_object (&plugin_loader->pending_apps);
+			g_mutex_unlock (&plugin_loader->pending_apps_mutex);
+
+			save_install_queue (plugin_loader);
+		}
+		return;
+	}
+
+	for (guint i = 0; i < gs_app_list_length (old_queue); i++) {
+		GsApp *app = gs_app_list_index (old_queue, i);
+
+		if (gs_app_list_lookup (refined_queue, gs_app_get_unique_id (app)) == NULL)
+			remove_app_from_install_queue (plugin_loader, app);
+	}
+
+	for (guint i = 0; i < gs_app_list_length (refined_queue); i++) {
+		GsApp *app = gs_app_list_index (refined_queue, i);
+		g_autoptr(GsPluginJob) plugin_job = NULL;
+
+		if (gs_app_get_kind (app) == AS_COMPONENT_KIND_REPOSITORY) {
+			plugin_job = gs_plugin_job_manage_repository_new (app,
+									  GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_INTERACTIVE |
+									  GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_INSTALL);
+		} else {
+			/* The 'interactive' is needed for credentials prompt, otherwise it just fails */
+			plugin_job = gs_plugin_job_newv (GS_PLUGIN_ACTION_INSTALL,
+							 "app", app,
+							 "interactive", TRUE,
+							 NULL);
+		}
+
+		gs_plugin_loader_job_process_async (plugin_loader, plugin_job,
+						    gs_app_get_cancellable (app),
+						    gs_plugin_loader_app_installed_cb,
+						    g_object_ref (app));
+	}
+
+	g_clear_object (&plugin_loader->pending_apps_cancellable);
+}
+
+static void
+gs_plugin_loader_maybe_flush_pending_install_queue (GsPluginLoader *plugin_loader)
+{
+	g_autoptr(GsPluginJob) plugin_job = NULL;
+	g_autoptr(GsAppList) obsolete = NULL;
+	g_autoptr(GsAppList) queue = NULL;
+
+	if (!gs_plugin_loader_get_network_available (plugin_loader) ||
+	    gs_plugin_loader_get_network_metered (plugin_loader)) {
+		/* Print the debug message only when had anything to skip */
+		g_mutex_lock (&plugin_loader->pending_apps_mutex);
+		if (plugin_loader->pending_apps != NULL) {
+			g_debug ("Cannot flush pending install queue, because is %sonline and is %smetered",
+				 !gs_plugin_loader_get_network_available (plugin_loader) ? "not " : "",
+				 gs_plugin_loader_get_network_metered (plugin_loader) ? "" : "not ");
+		}
+		g_mutex_unlock (&plugin_loader->pending_apps_mutex);
+		return;
+	}
+
+	/* Already flushing pending queue */
+	if (plugin_loader->pending_apps_cancellable)
+		return;
+
+	queue = gs_app_list_new ();
+	obsolete = gs_app_list_new ();
+	g_mutex_lock (&plugin_loader->pending_apps_mutex);
+	for (guint i = 0; plugin_loader->pending_apps != NULL && i < gs_app_list_length (plugin_loader->pending_apps); i++) {
+		GsApp *app = gs_app_list_index (plugin_loader->pending_apps, i);
+		if (gs_app_get_state (app) == GS_APP_STATE_QUEUED_FOR_INSTALL) {
+			gs_app_set_state (app, GS_APP_STATE_AVAILABLE);
+			gs_app_list_add (queue, app);
+		} else {
+			gs_app_list_add (obsolete, app);
+		}
+	}
+	g_mutex_unlock (&plugin_loader->pending_apps_mutex);
+	for (guint i = 0; i < gs_app_list_length (obsolete); i++) {
+		GsApp *app = gs_app_list_index (obsolete, i);
+		remove_app_from_install_queue (plugin_loader, app);
+	}
+
+	plugin_loader->pending_apps_cancellable = g_cancellable_new ();
+
+	plugin_job = gs_plugin_job_refine_new (queue, GS_PLUGIN_REFINE_FLAGS_NONE);
+	gs_plugin_loader_job_process_async (plugin_loader, plugin_job,
+					    plugin_loader->pending_apps_cancellable,
+					    gs_plugin_loader_pending_apps_refined_cb,
+					    g_steal_pointer (&queue));
+}
+
+static void
+gs_plugin_loader_network_changed_cb (GNetworkMonitor *monitor,
+				     gboolean available,
+				     GsPluginLoader *plugin_loader)
+{
+	gboolean metered = g_network_monitor_get_network_metered (plugin_loader->network_monitor);
+
+	g_debug ("network status change: %s [%s]",
+		 available ? "online" : "offline",
+		 metered ? "metered" : "unmetered");
+
+	g_object_notify_by_pspec (G_OBJECT (plugin_loader), obj_props[PROP_NETWORK_AVAILABLE]);
+	g_object_notify_by_pspec (G_OBJECT (plugin_loader), obj_props[PROP_NETWORK_METERED]);
+
+	gs_plugin_loader_maybe_flush_pending_install_queue (plugin_loader);
+}
+
+static void
+gs_plugin_loader_network_available_notify_cb (GObject    *obj,
+					      GParamSpec *pspec,
+					      gpointer    user_data)
+{
+	GNetworkMonitor *monitor = G_NETWORK_MONITOR (obj);
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (user_data);
+
+	gs_plugin_loader_network_changed_cb (monitor, g_network_monitor_get_network_available (monitor), plugin_loader);
+}
+
+static void
+gs_plugin_loader_network_metered_notify_cb (GObject    *obj,
+					    GParamSpec *pspec,
+					    gpointer    user_data)
+{
+	GNetworkMonitor *monitor = G_NETWORK_MONITOR (obj);
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (user_data);
+
+	gs_plugin_loader_network_changed_cb (monitor, g_network_monitor_get_network_available (monitor), plugin_loader);
+}
+
+static void
+gs_plugin_loader_monitor_network (GsPluginLoader *plugin_loader)
+{
+	GNetworkMonitor *network_monitor;
+
+	network_monitor = g_network_monitor_get_default ();
+	if (network_monitor == NULL || plugin_loader->network_changed_handler != 0)
+		return;
+	plugin_loader->network_monitor = g_object_ref (network_monitor);
+
+	plugin_loader->network_changed_handler =
+		g_signal_connect (plugin_loader->network_monitor, "network-changed",
+				  G_CALLBACK (gs_plugin_loader_network_changed_cb), plugin_loader);
+	plugin_loader->network_available_notify_handler =
+		g_signal_connect (plugin_loader->network_monitor, "notify::network-available",
+				  G_CALLBACK (gs_plugin_loader_network_available_notify_cb), plugin_loader);
+	plugin_loader->network_metered_notify_handler =
+		g_signal_connect (plugin_loader->network_monitor, "notify::network-metered",
+				  G_CALLBACK (gs_plugin_loader_network_metered_notify_cb), plugin_loader);
+
+	gs_plugin_loader_network_changed_cb (plugin_loader->network_monitor,
+			    g_network_monitor_get_network_available (plugin_loader->network_monitor),
+			    plugin_loader);
+}
+
+/******************************************************************************/
+
+static void
+generic_update_cancelled_cb (GCancellable *cancellable, gpointer data)
+{
+	GCancellable *app_cancellable = G_CANCELLABLE (data);
+	g_cancellable_cancel (app_cancellable);
+}
+
+static gboolean
+gs_plugin_loader_generic_update (GsPluginLoader *plugin_loader,
+				 GsPluginLoaderHelper *helper,
+				 GCancellable *cancellable,
+				 GError **error)
+{
+	guint cancel_handler_id = 0;
+	GsAppList *list;
+
+	/* run each plugin, per-app version */
+	list = gs_plugin_job_get_list (helper->plugin_job);
+	for (guint i = 0; i < plugin_loader->plugins->len; i++) {
+		GsPluginActionFunc plugin_app_func = NULL;
+		GsPlugin *plugin = g_ptr_array_index (plugin_loader->plugins, i);
+		if (g_cancellable_set_error_if_cancelled (cancellable, error)) {
+			gs_utils_error_convert_gio (error);
+			return FALSE;
+		}
+		plugin_app_func = gs_plugin_get_symbol (plugin, helper->function_name);
+		if (plugin_app_func == NULL)
+			continue;
+
+		/* for each app */
+		for (guint j = 0; j < gs_app_list_length (list); j++) {
+			GCancellable *app_cancellable;
+			GsApp *app = gs_app_list_index (list, j);
+			gboolean ret;
+			g_autoptr(GError) error_local = NULL;
+
+			/* if the whole operation should be cancelled */
+			if (g_cancellable_set_error_if_cancelled (cancellable, error))
+				return FALSE;
+
+			/* already installed? */
+			if (gs_app_get_state (app) == GS_APP_STATE_INSTALLED)
+				continue;
+
+			/* make sure that the app update is cancelled when the whole op is cancelled */
+			app_cancellable = gs_app_get_cancellable (app);
+			cancel_handler_id = g_cancellable_connect (cancellable,
+								   G_CALLBACK (generic_update_cancelled_cb),
+								   g_object_ref (app_cancellable),
+								   g_object_unref);
+
+			gs_plugin_job_set_app (helper->plugin_job, app);
+			ret = plugin_app_func (plugin, app, app_cancellable, &error_local);
+			g_cancellable_disconnect (cancellable, cancel_handler_id);
+
+			if (!ret) {
+				if (!gs_plugin_error_handle_failure (helper,
+								     plugin,
+								     error_local,
+								     error)) {
+					return FALSE;
+				}
+			}
+		}
+		helper->anything_ran = TRUE;
+		gs_plugin_status_update (plugin, NULL, GS_PLUGIN_STATUS_FINISHED);
+	}
+
+	if (gs_plugin_job_get_action (helper->plugin_job) == GS_PLUGIN_ACTION_UPDATE)
+		gs_utils_set_online_updates_timestamp (plugin_loader->settings);
+
+	return TRUE;
+}
+
+static void
+gs_plugin_loader_inherit_list_props (GsAppList *des_list,
+				     GsAppList *src_list)
+{
+	if (gs_app_list_has_flag (src_list, GS_APP_LIST_FLAG_IS_TRUNCATED))
+		gs_app_list_add_flag (des_list, GS_APP_LIST_FLAG_IS_TRUNCATED);
+
+	gs_app_list_set_size_peak (des_list, gs_app_list_get_size_peak (src_list));
+}
+
+static void
+gs_plugin_loader_process_thread_cb (GTask *task,
+				    gpointer object,
+				    gpointer task_data,
+				    GCancellable *cancellable)
+{
+	GError *error = NULL;
+	GsPluginLoaderHelper *helper = (GsPluginLoaderHelper *) task_data;
+	GsAppListFilterFlags dedupe_flags;
+	g_autoptr(GsAppList) list = g_object_ref (gs_plugin_job_get_list (helper->plugin_job));
+	GsPluginAction action = gs_plugin_job_get_action (helper->plugin_job);
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (object);
+	gboolean add_to_pending_array = FALSE;
+	g_autoptr(GMainContext) context = g_main_context_new ();
+	g_autoptr(GMainContextPusher) pusher = g_main_context_pusher_new (context);
+	g_autofree gchar *job_debug = NULL;
+#ifdef HAVE_SYSPROF
+	gint64 begin_time_nsec G_GNUC_UNUSED = SYSPROF_CAPTURE_CURRENT_TIME;
+#endif
+
+	/* these change the pending count on the installed panel */
+	switch (action) {
+	case GS_PLUGIN_ACTION_INSTALL:
+	case GS_PLUGIN_ACTION_REMOVE:
+		add_to_pending_array = TRUE;
+		break;
+	default:
+		break;
+	}
+
+	/* add to pending list */
+	if (add_to_pending_array)
+		gs_plugin_loader_pending_apps_add (plugin_loader, helper);
+
+	/* run each plugin */
+	if (!GS_IS_PLUGIN_JOB_REFINE (helper->plugin_job)) {
+		if (!gs_plugin_loader_run_results (helper, cancellable, &error)) {
+			if (add_to_pending_array) {
+				gs_app_set_state_recover (gs_plugin_job_get_app (helper->plugin_job));
+				gs_plugin_loader_pending_apps_remove (plugin_loader, helper);
+			}
+			gs_utils_error_convert_gio (&error);
+			g_task_return_error (task, error);
+			return;
+		}
+
+		if (action == GS_PLUGIN_ACTION_URL_TO_APP) {
+			const gchar *search = gs_plugin_job_get_search (helper->plugin_job);
+			if (search && g_ascii_strncasecmp (search, "file://", 7) == 0 && (
+			    gs_plugin_job_get_list (helper->plugin_job) == NULL ||
+			    gs_app_list_length (gs_plugin_job_get_list (helper->plugin_job)) == 0)) {
+				g_autoptr(GError) local_error = NULL;
+				g_autoptr(GFile) file = NULL;
+				file = g_file_new_for_uri (search);
+				gs_plugin_job_set_action (helper->plugin_job, GS_PLUGIN_ACTION_FILE_TO_APP);
+				gs_plugin_job_set_file (helper->plugin_job, file);
+				helper->function_name = gs_plugin_action_to_function_name (GS_PLUGIN_ACTION_FILE_TO_APP);
+				if (gs_plugin_loader_run_results (helper, cancellable, &local_error)) {
+					for (guint j = 0; j < gs_app_list_length (list); j++) {
+						GsApp *app = gs_app_list_index (list, j);
+						if (gs_app_get_local_file (app) == NULL)
+							gs_app_set_local_file (app, gs_plugin_job_get_file (helper->plugin_job));
+					}
+				} else {
+					g_debug ("Failed to convert file:// URI to app using file-to-app action: %s", local_error->message);
+				}
+				gs_plugin_job_set_action (helper->plugin_job, GS_PLUGIN_ACTION_URL_TO_APP);
+				gs_plugin_job_set_file (helper->plugin_job, NULL);
+			}
+		}
+	}
+
+	/* run per-app version */
+	if (action == GS_PLUGIN_ACTION_UPDATE) {
+		helper->function_name = "gs_plugin_update_app";
+		if (!gs_plugin_loader_generic_update (plugin_loader, helper,
+						      cancellable, &error)) {
+			gs_utils_error_convert_gio (&error);
+			g_task_return_error (task, error);
+			return;
+		}
+	} else if (action == GS_PLUGIN_ACTION_DOWNLOAD) {
+		helper->function_name = "gs_plugin_download_app";
+		if (!gs_plugin_loader_generic_update (plugin_loader, helper,
+						      cancellable, &error)) {
+			gs_utils_error_convert_gio (&error);
+			g_task_return_error (task, error);
+			return;
+		}
+	}
+
+	if (action == GS_PLUGIN_ACTION_UPGRADE_TRIGGER)
+		gs_utils_set_online_updates_timestamp (plugin_loader->settings);
+
+	/* remove from pending list */
+	if (add_to_pending_array)
+		gs_plugin_loader_pending_apps_remove (plugin_loader, helper);
+
+	/* some functions are really required for proper operation */
+	switch (action) {
+	case GS_PLUGIN_ACTION_GET_UPDATES:
+	case GS_PLUGIN_ACTION_INSTALL:
+	case GS_PLUGIN_ACTION_DOWNLOAD:
+	case GS_PLUGIN_ACTION_LAUNCH:
+	case GS_PLUGIN_ACTION_REMOVE:
+	case GS_PLUGIN_ACTION_UPDATE:
+		if (!helper->anything_ran) {
+			g_set_error (&error,
+				     GS_PLUGIN_ERROR,
+				     GS_PLUGIN_ERROR_NOT_SUPPORTED,
+				     "no plugin could handle %s",
+				     gs_plugin_action_to_string (action));
+			g_task_return_error (task, error);
+			return;
+		}
+		break;
+	default:
+		if (!helper->anything_ran && !GS_IS_PLUGIN_JOB_REFINE (helper->plugin_job)) {
+			g_debug ("no plugin could handle %s",
+				 gs_plugin_action_to_string (action));
+		}
+		break;
+	}
+
+	/* unstage addons */
+	if (add_to_pending_array) {
+		g_autoptr(GsAppList) addons = gs_app_dup_addons (gs_plugin_job_get_app (helper->plugin_job));
+
+		for (guint i = 0; addons != NULL && i < gs_app_list_length (addons); i++) {
+			GsApp *addon = gs_app_list_index (addons, i);
+			if (gs_app_get_to_be_installed (addon))
+				gs_app_set_to_be_installed (addon, FALSE);
+		}
+	}
+
+	/* filter to reduce to a sane set */
+	gs_plugin_loader_job_sorted_truncation (helper->plugin_job, list);
+
+	/* set the local file on any of the returned results */
+	switch (action) {
+	case GS_PLUGIN_ACTION_FILE_TO_APP:
+		for (guint j = 0; j < gs_app_list_length (list); j++) {
+			GsApp *app = gs_app_list_index (list, j);
+			if (gs_app_get_local_file (app) == NULL)
+				gs_app_set_local_file (app, gs_plugin_job_get_file (helper->plugin_job));
+		}
+	default:
+		break;
+	}
+
+	/* pick up new source id */
+	switch (action) {
+	case GS_PLUGIN_ACTION_INSTALL:
+	case GS_PLUGIN_ACTION_REMOVE:
+		gs_plugin_job_add_refine_flags (helper->plugin_job,
+		                                GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN |
+		                                GS_PLUGIN_REFINE_FLAGS_REQUIRE_SETUP_ACTION);
+		break;
+	default:
+		break;
+	}
+
+	/* run refine() on each one if required */
+	if (gs_plugin_job_get_refine_flags (helper->plugin_job) != 0 &&
+	    list != NULL &&
+	    gs_app_list_length (list) > 0) {
+		g_autoptr(GsPluginJob) refine_job = NULL;
+		g_autoptr(GAsyncResult) refine_result = NULL;
+		g_autoptr(GsAppList) new_list = NULL;
+
+		refine_job = gs_plugin_job_refine_new (list, gs_plugin_job_get_refine_flags (helper->plugin_job) | GS_PLUGIN_REFINE_FLAGS_DISABLE_FILTERING);
+		gs_plugin_loader_job_process_async (plugin_loader, refine_job,
+						    cancellable,
+						    async_result_cb,
+						    &refine_result);
+
+		/* FIXME: Make this sync until the enclosing function is
+		 * refactored to be async. */
+		while (refine_result == NULL)
+			g_main_context_iteration (g_main_context_get_thread_default (), TRUE);
+
+		new_list = gs_plugin_loader_job_process_finish (plugin_loader, refine_result, &error);
+		if (new_list == NULL) {
+			gs_utils_error_convert_gio (&error);
+			g_task_return_error (task, g_steal_pointer (&error));
+			return;
+		}
+
+		gs_plugin_loader_inherit_list_props (new_list, list);
+
+		/* Update the app list in case the refine resolved any wildcards. */
+		g_set_object (&list, new_list);
+	} else {
+		g_debug ("no refine flags set for transaction");
+	}
+
+	/* check the local files have an icon set */
+	switch (action) {
+	case GS_PLUGIN_ACTION_URL_TO_APP:
+	case GS_PLUGIN_ACTION_FILE_TO_APP: {
+		g_autoptr(GsPluginJob) refine_job = NULL;
+		g_autoptr(GAsyncResult) refine_result = NULL;
+		g_autoptr(GsAppList) new_list = NULL;
+
+		for (guint j = 0; j < gs_app_list_length (list); j++) {
+			GsApp *app = gs_app_list_index (list, j);
+			if (gs_app_get_icons (app) == NULL) {
+				g_autoptr(GIcon) ic = NULL;
+				const gchar *icon_name;
+				if (gs_app_has_quirk (app, GS_APP_QUIRK_HAS_SOURCE))
+					icon_name = "x-package-repository";
+				else
+					icon_name = "system-component-application";
+				ic = g_themed_icon_new (icon_name);
+				gs_app_add_icon (app, ic);
+			}
+		}
+
+		refine_job = gs_plugin_job_refine_new (list, GS_PLUGIN_REFINE_FLAGS_REQUIRE_ICON | GS_PLUGIN_REFINE_FLAGS_DISABLE_FILTERING);
+		gs_plugin_loader_job_process_async (plugin_loader, refine_job,
+						    cancellable,
+						    async_result_cb,
+						    &refine_result);
+
+		/* FIXME: Make this sync until the enclosing function is
+		 * refactored to be async. */
+		while (refine_result == NULL)
+			g_main_context_iteration (g_main_context_get_thread_default (), TRUE);
+
+		new_list = gs_plugin_loader_job_process_finish (plugin_loader, refine_result, &error);
+		if (new_list == NULL) {
+			gs_utils_error_convert_gio (&error);
+			g_task_return_error (task, g_steal_pointer (&error));
+			return;
+		}
+
+		gs_plugin_loader_inherit_list_props (new_list, list);
+
+		/* Update the app list in case the refine resolved any wildcards. */
+		g_set_object (&list, new_list);
+
+		break;
+	}
+	default:
+		break;
+	}
+
+	/* filter package list */
+	switch (action) {
+	case GS_PLUGIN_ACTION_URL_TO_APP:
+		gs_app_list_filter (list, gs_plugin_loader_app_is_valid_filter, helper);
+		break;
+	case GS_PLUGIN_ACTION_GET_UPDATES:
+		gs_app_list_filter (list, gs_plugin_loader_app_is_valid_updatable, helper);
+		break;
+	default:
+		break;
+	}
+
+	/* only allow one result */
+	if (action == GS_PLUGIN_ACTION_URL_TO_APP ||
+	    action == GS_PLUGIN_ACTION_FILE_TO_APP) {
+		if (gs_app_list_length (list) == 0) {
+			g_autofree gchar *str = gs_plugin_job_to_string (helper->plugin_job);
+			g_autoptr(GError) error_local = NULL;
+			g_set_error (&error_local,
+				     GS_PLUGIN_ERROR,
+				     GS_PLUGIN_ERROR_NOT_SUPPORTED,
+				     "no application was created for %s", str);
+			if (!gs_plugin_job_get_propagate_error (helper->plugin_job))
+				gs_plugin_loader_claim_job_error (plugin_loader, NULL, helper->plugin_job, error_local);
+			g_task_return_error (task, g_steal_pointer (&error_local));
+			return;
+		}
+		if (gs_app_list_length (list) > 1) {
+			g_autofree gchar *str = gs_plugin_job_to_string (helper->plugin_job);
+			g_debug ("more than one application was created for %s", str);
+		}
+	}
+
+	/* filter duplicates with priority, taking into account the source name
+	 * & version, so we combine available updates with the installed app */
+	dedupe_flags = gs_plugin_job_get_dedupe_flags (helper->plugin_job);
+	if (dedupe_flags != GS_APP_LIST_FILTER_FLAG_NONE)
+		gs_app_list_filter_duplicates (list, dedupe_flags);
+
+	/* sort these again as the refine may have added useful metadata */
+	gs_plugin_loader_job_sorted_truncation_again (helper->plugin_job, list);
+
+#ifdef HAVE_SYSPROF
+	if (plugin_loader->sysprof_writer != NULL) {
+		g_autofree gchar *sysprof_name = g_strconcat ("process-thread:", gs_plugin_action_to_string (action), NULL);
+		g_autofree gchar *sysprof_message = gs_plugin_job_to_string (helper->plugin_job);
+		sysprof_capture_writer_add_mark (plugin_loader->sysprof_writer,
+						 begin_time_nsec,
+						 sched_getcpu (),
+						 getpid (),
+						 SYSPROF_CAPTURE_CURRENT_TIME - begin_time_nsec,
+						 "gnome-software",
+						 sysprof_name,
+						 sysprof_message);
+	}
+#endif  /* HAVE_SYSPROF */
+
+	/* show elapsed time */
+	job_debug = gs_plugin_job_to_string (helper->plugin_job);
+	g_debug ("%s", job_debug);
+
+	/* success */
+	g_task_return_pointer (task, g_object_ref (list), (GDestroyNotify) g_object_unref);
+}
+
+static void
+gs_plugin_loader_process_in_thread_pool_cb (gpointer data,
+					    gpointer user_data)
+{
+	GTask *task = data;
+	gpointer source_object = g_task_get_source_object (task);
+	gpointer task_data = g_task_get_task_data (task);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+	GsPluginLoaderHelper *helper = g_task_get_task_data (task);
+	GsApp *app = gs_plugin_job_get_app (helper->plugin_job);
+	GsPluginAction action = gs_plugin_job_get_action (helper->plugin_job);
+
+	gs_ioprio_set (G_PRIORITY_LOW);
+
+	gs_plugin_loader_process_thread_cb (task, source_object, task_data, cancellable);
+
+	/* Clear any pending action set in gs_plugin_loader_schedule_task() */
+	if (app != NULL && gs_app_get_pending_action (app) == action)
+		gs_app_set_pending_action (app, GS_PLUGIN_ACTION_UNKNOWN);
+
+	g_object_unref (task);
+}
+
+static void
+gs_plugin_loader_cancelled_cb (GCancellable *cancellable,
+                               gpointer      user_data)
+{
+	GCancellable *child_cancellable = G_CANCELLABLE (user_data);
+
+	/* just proxy this forward */
+	g_debug ("Cancelling job with cancellable %p", child_cancellable);
+	g_cancellable_cancel (child_cancellable);
+}
+
+static void
+gs_plugin_loader_schedule_task (GsPluginLoader *plugin_loader,
+				GTask *task)
+{
+	GsPluginLoaderHelper *helper = g_task_get_task_data (task);
+	GsApp *app = gs_plugin_job_get_app (helper->plugin_job);
+
+	if (app != NULL) {
+		/* set the pending-action to the app */
+		GsPluginAction action = gs_plugin_job_get_action (helper->plugin_job);
+		gs_app_set_pending_action (app, action);
+
+		if (action == GS_PLUGIN_ACTION_INSTALL &&
+		    gs_app_get_state (app) != GS_APP_STATE_AVAILABLE_LOCAL)
+			add_app_to_install_queue (plugin_loader, app);
+	}
+	g_thread_pool_push (plugin_loader->queued_ops_pool, g_object_ref (task), NULL);
+}
+
+static void
+run_job_cb (GObject      *source_object,
+            GAsyncResult *result,
+            gpointer      user_data)
+{
+	GsPluginJob *plugin_job = GS_PLUGIN_JOB (source_object);
+	GsPluginJobClass *job_class;
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	g_autoptr(GError) local_error = NULL;
+#ifdef HAVE_SYSPROF
+	GsPluginLoader *plugin_loader = g_task_get_source_object (task);
+	gint64 begin_time_nsec = GPOINTER_TO_SIZE (g_task_get_task_data (task));
+
+	if (plugin_loader->sysprof_writer != NULL) {
+		g_autofree gchar *sysprof_name = g_strconcat ("process-thread:", G_OBJECT_TYPE_NAME (plugin_job), NULL);
+		g_autofree gchar *sysprof_message = gs_plugin_job_to_string (plugin_job);
+		sysprof_capture_writer_add_mark (plugin_loader->sysprof_writer,
+						 begin_time_nsec,
+						 sched_getcpu (),
+						 getpid (),
+						 SYSPROF_CAPTURE_CURRENT_TIME - begin_time_nsec,
+						 "gnome-software",
+						 sysprof_name,
+						 sysprof_message);
+	}
+#endif  /* HAVE_SYSPROF */
+
+	/* FIXME: This will eventually go away when
+	 * gs_plugin_loader_job_process_finish() is removed. */
+	job_class = GS_PLUGIN_JOB_GET_CLASS (plugin_job);
+
+	g_assert (job_class->run_finish != NULL);
+
+	if (!job_class->run_finish (plugin_job, result, &local_error)) {
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	if (GS_IS_PLUGIN_JOB_REFINE (plugin_job)) {
+		GsAppList *list = gs_plugin_job_refine_get_result_list (GS_PLUGIN_JOB_REFINE (plugin_job));
+		g_task_return_pointer (task, g_object_ref (list), (GDestroyNotify) g_object_unref);
+		return;
+	} else if (GS_IS_PLUGIN_JOB_LIST_APPS (plugin_job)) {
+		GsAppList *list = gs_plugin_job_list_apps_get_result_list (GS_PLUGIN_JOB_LIST_APPS (plugin_job));
+		g_task_return_pointer (task, g_object_ref (list), (GDestroyNotify) g_object_unref);
+		return;
+	} else if (GS_IS_PLUGIN_JOB_LIST_DISTRO_UPGRADES (plugin_job)) {
+		GsAppList *list = gs_plugin_job_list_distro_upgrades_get_result_list (GS_PLUGIN_JOB_LIST_DISTRO_UPGRADES (plugin_job));
+		g_task_return_pointer (task, g_object_ref (list), (GDestroyNotify) g_object_unref);
+		return;
+	} else if (GS_IS_PLUGIN_JOB_REFRESH_METADATA (plugin_job)) {
+		/* FIXME: For some reason, existing callers of refresh jobs
+		 * expect a #GsAppList instance back, even though it’s empty and
+		 * they don’t use its contents. It’s just used to distinguish
+		 * against returning an error. This will go away when
+		 * job_process_async() does. */
+		g_task_return_pointer (task, gs_app_list_new (), g_object_unref);
+		return;
+	} else if (GS_IS_PLUGIN_JOB_MANAGE_REPOSITORY (plugin_job) ||
+		   GS_IS_PLUGIN_JOB_LIST_CATEGORIES (plugin_job)) {
+		/* FIXME: The gs_plugin_loader_job_action_finish() expects a #GsAppList
+		 * pointer on success, thus return it. */
+		g_task_return_pointer (task, gs_app_list_new (), g_object_unref);
+		return;
+	}
+
+	g_assert_not_reached ();
+}
+
+typedef struct {
+	GWeakRef parent_cancellable_weak;
+	gulong handler_id;
+} CancellableData;
+
+static void
+cancellable_data_free (CancellableData *data)
+{
+	g_autoptr(GCancellable) parent_cancellable = g_weak_ref_get (&data->parent_cancellable_weak);
+
+	if (parent_cancellable != NULL)
+		g_cancellable_disconnect (parent_cancellable, data->handler_id);
+
+	g_weak_ref_clear (&data->parent_cancellable_weak);
+	g_free (data);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (CancellableData, cancellable_data_free)
+
+static void
+plugin_loader_task_freed_cb (gpointer user_data,
+			     GObject *freed_object)
+{
+	g_autoptr(GsPluginLoader) plugin_loader = user_data;
+	if (g_atomic_int_dec_and_test (&plugin_loader->active_jobs)) {
+		/* if the plugin used updates-changed during its job, actually schedule
+		 * the signal emission now */
+		if (plugin_loader->updates_changed_cnt > 0)
+			gs_plugin_loader_updates_changed (plugin_loader);
+	}
+}
+
+static gboolean job_process_setup_complete_cb (GCancellable *cancellable,
+                                               gpointer      user_data);
+static void job_process_cb (GTask *task);
+
+/**
+ * gs_plugin_loader_job_process_async:
+ * @plugin_loader: A #GsPluginLoader
+ * @plugin_job: job to process
+ * @cancellable: a #GCancellable, or %NULL
+ * @callback: function to call when complete
+ * @user_data: user data to pass to @callback
+ *
+ * This method calls all plugins.
+ *
+ * If the #GsPluginLoader is still being set up, this function will wait until
+ * setup is complete before running.
+ **/
+void
+gs_plugin_loader_job_process_async (GsPluginLoader *plugin_loader,
+				    GsPluginJob *plugin_job,
+				    GCancellable *cancellable,
+				    GAsyncReadyCallback callback,
+				    gpointer user_data)
+{
+	GsPluginJobClass *job_class;
+	GsPluginAction action;
+	g_autoptr(GTask) task = NULL;
+	g_autoptr(GCancellable) cancellable_job = NULL;
+	g_autofree gchar *task_name = NULL;
+
+	g_return_if_fail (GS_IS_PLUGIN_LOADER (plugin_loader));
+	g_return_if_fail (GS_IS_PLUGIN_JOB (plugin_job));
+	g_return_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable));
+
+	job_class = GS_PLUGIN_JOB_GET_CLASS (plugin_job);
+	action = gs_plugin_job_get_action (plugin_job);
+
+	if (job_class->run_async != NULL) {
+		task_name = g_strdup_printf ("%s %s", G_STRFUNC, G_OBJECT_TYPE_NAME (plugin_job));
+		cancellable_job = (cancellable != NULL) ? g_object_ref (cancellable) : NULL;
+	} else {
+		task_name = g_strdup_printf ("%s %s", G_STRFUNC, gs_plugin_action_to_string (action));
+		cancellable_job = g_cancellable_new ();
+
+		/* Old-style jobs always have a valid cancellable, so proxy the caller */
+		g_debug ("Chaining cancellation from %p to %p", cancellable, cancellable_job);
+		if (cancellable != NULL) {
+			g_autoptr(CancellableData) cancellable_data = NULL;
+
+			cancellable_data = g_new0 (CancellableData, 1);
+			g_weak_ref_init (&cancellable_data->parent_cancellable_weak, cancellable);
+			cancellable_data->handler_id = g_cancellable_connect (cancellable,
+									      G_CALLBACK (gs_plugin_loader_cancelled_cb),
+									      cancellable_job, NULL);
+
+			g_object_set_data_full (G_OBJECT (cancellable_job),
+						"gs-cancellable-chain",
+						g_steal_pointer (&cancellable_data),
+						(GDestroyNotify) cancellable_data_free);
+		}
+	}
+
+	task = g_task_new (plugin_loader, cancellable_job, callback, user_data);
+	g_task_set_name (task, task_name);
+	g_task_set_task_data (task, g_object_ref (plugin_job), (GDestroyNotify) g_object_unref);
+
+	g_atomic_int_inc (&plugin_loader->active_jobs);
+	g_object_weak_ref (G_OBJECT (task),
+		plugin_loader_task_freed_cb, g_object_ref (plugin_loader));
+
+	/* Wait until the plugin has finished setting up.
+	 *
+	 * Do this using a #GCancellable. While we’re not using the #GCancellable
+	 * to cancel anything, it is a reliable way to signal between threads
+	 * without polling, waking up all waiting #GMainContexts when it’s
+	 * ‘cancelled’. */
+	if (plugin_loader->setup_complete) {
+		job_process_cb (task);
+	} else {
+		g_autoptr(GSource) cancellable_source = g_cancellable_source_new (plugin_loader->setup_complete_cancellable);
+		g_task_attach_source (task, cancellable_source, G_SOURCE_FUNC (job_process_setup_complete_cb));
+	}
+}
+
+static gboolean
+job_process_setup_complete_cb (GCancellable *cancellable,
+                               gpointer      user_data)
+{
+	GTask *task = G_TASK (user_data);
+
+	job_process_cb (task);
+
+	return G_SOURCE_REMOVE;
+}
+
+static void
+job_process_cb (GTask *task)
+{
+	g_autoptr(GsPluginJob) plugin_job = g_object_ref (g_task_get_task_data (task));
+	GsPluginLoader *plugin_loader = g_task_get_source_object (task);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+	GsPluginJobClass *job_class;
+	GsPluginAction action;
+	GsPluginLoaderHelper *helper;
+
+	job_class = GS_PLUGIN_JOB_GET_CLASS (plugin_job);
+	action = gs_plugin_job_get_action (plugin_job);
+
+	/* If the job provides a more specific async run function, use that.
+	 *
+	 * FIXME: This will eventually go away when
+	 * gs_plugin_loader_job_process_async() is removed. */
+
+	if (job_class->run_async != NULL) {
+#ifdef HAVE_SYSPROF
+		gint64 begin_time_nsec G_GNUC_UNUSED = SYSPROF_CAPTURE_CURRENT_TIME;
+
+		g_task_set_task_data (task, GSIZE_TO_POINTER (begin_time_nsec), NULL);
+#endif
+
+		job_class->run_async (plugin_job, plugin_loader, cancellable,
+				      run_job_cb, g_object_ref (task));
+		return;
+	}
+
+	/* check job has valid action */
+	if (action == GS_PLUGIN_ACTION_UNKNOWN) {
+		g_autofree gchar *job_str = gs_plugin_job_to_string (plugin_job);
+		g_task_return_new_error (task,
+					 GS_PLUGIN_ERROR,
+					 GS_PLUGIN_ERROR_NOT_SUPPORTED,
+					 "job has no valid action: %s", job_str);
+		return;
+	}
+
+	/* deal with the install queue */
+	if (action == GS_PLUGIN_ACTION_REMOVE) {
+		if (remove_app_from_install_queue (plugin_loader, gs_plugin_job_get_app (plugin_job))) {
+			GsAppList *list = gs_plugin_job_get_list (plugin_job);
+			g_task_return_pointer (task, g_object_ref (list), (GDestroyNotify) g_object_unref);
+			return;
+		}
+	}
+
+	/* FIXME: the plugins should specify this, rather than hardcoding */
+	if (gs_plugin_job_has_refine_flags (plugin_job,
+					    GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN_UI)) {
+		gs_plugin_job_add_refine_flags (plugin_job,
+						GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN);
+	}
+	if (gs_plugin_job_has_refine_flags (plugin_job,
+					    GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN_HOSTNAME)) {
+		gs_plugin_job_add_refine_flags (plugin_job,
+						GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN);
+	}
+	if (gs_plugin_job_has_refine_flags (plugin_job,
+					    GS_PLUGIN_REFINE_FLAGS_REQUIRE_SIZE)) {
+		gs_plugin_job_add_refine_flags (plugin_job,
+						GS_PLUGIN_REFINE_FLAGS_REQUIRE_RUNTIME);
+	}
+
+	/* FIXME: this is probably a bug */
+	if (action == GS_PLUGIN_ACTION_GET_SOURCES) {
+		gs_plugin_job_add_refine_flags (plugin_job,
+						GS_PLUGIN_REFINE_FLAGS_REQUIRE_SETUP_ACTION);
+	}
+
+	/* check required args */
+	switch (action) {
+	case GS_PLUGIN_ACTION_URL_TO_APP:
+		if (gs_plugin_job_get_search (plugin_job) == NULL) {
+			g_task_return_new_error (task,
+						 GS_PLUGIN_ERROR,
+						 GS_PLUGIN_ERROR_NOT_SUPPORTED,
+						 "no valid search terms");
+			return;
+		}
+		break;
+	default:
+		break;
+	}
+
+	/* save helper */
+	helper = gs_plugin_loader_helper_new (plugin_loader, plugin_job);
+	g_task_set_task_data (task, helper, (GDestroyNotify) gs_plugin_loader_helper_free);
+
+	/* let the task cancel itself */
+	g_task_set_check_cancellable (task, FALSE);
+	g_task_set_return_on_cancel (task, FALSE);
+
+	switch (action) {
+	case GS_PLUGIN_ACTION_INSTALL:
+	case GS_PLUGIN_ACTION_UPDATE:
+	case GS_PLUGIN_ACTION_UPGRADE_DOWNLOAD:
+		/* these actions must be performed by the thread pool because we
+		 * want to limit the number of them running in parallel */
+		gs_plugin_loader_schedule_task (plugin_loader, task);
+		return;
+	default:
+		break;
+	}
+
+	/* run in a thread */
+	g_task_run_in_thread (task, gs_plugin_loader_process_thread_cb);
+}
+
+/******************************************************************************/
+
+/**
+ * gs_plugin_loader_get_plugin_supported:
+ * @plugin_loader: A #GsPluginLoader
+ * @function_name: a function name
+ *
+ * This function returns TRUE if the symbol is found in any enabled plugin.
+ */
+gboolean
+gs_plugin_loader_get_plugin_supported (GsPluginLoader *plugin_loader,
+				       const gchar *function_name)
+{
+	for (guint i = 0; i < plugin_loader->plugins->len; i++) {
+		GsPlugin *plugin = g_ptr_array_index (plugin_loader->plugins, i);
+		if (gs_plugin_get_symbol (plugin, function_name) != NULL)
+			return TRUE;
+	}
+	return FALSE;
+}
+
+/**
+ * gs_plugin_loader_get_plugins:
+ * @plugin_loader: a #GsPluginLoader
+ *
+ * Get the set of currently loaded plugins.
+ *
+ * This includes disabled plugins, which should be checked for using
+ * gs_plugin_get_enabled().
+ *
+ * This is intended to be used by internal gnome-software code. Plugin and UI
+ * code should typically use #GsPluginJob to run operations.
+ *
+ * Returns: (transfer none) (element-type GsPlugin): list of #GsPlugins
+ * Since: 42
+ */
+GPtrArray *
+gs_plugin_loader_get_plugins (GsPluginLoader *plugin_loader)
+{
+	g_return_val_if_fail (GS_IS_PLUGIN_LOADER (plugin_loader), NULL);
+
+	return plugin_loader->plugins;
+}
+
+static void app_create_cb (GObject      *source_object,
+                           GAsyncResult *result,
+                           gpointer      user_data);
+
+/**
+ * gs_plugin_loader_app_create_async:
+ * @plugin_loader: a #GsPluginLoader
+ * @unique_id: a unique_id
+ * @cancellable: a #GCancellable, or %NULL
+ * @callback: function to call when complete
+ * @user_data: user data to pass to @callback
+ *
+ * Create a #GsApp identified by @unique_id asynchronously.
+ * Finish the call with gs_plugin_loader_app_create_finish().
+ *
+ * If the #GsPluginLoader is still being set up, this function will wait until
+ * setup is complete before running.
+ *
+ * Since: 41
+ **/
+void
+gs_plugin_loader_app_create_async (GsPluginLoader *plugin_loader,
+				   const gchar *unique_id,
+				   GCancellable *cancellable,
+				   GAsyncReadyCallback callback,
+				   gpointer user_data)
+{
+	g_autoptr(GTask) task = NULL;
+	g_autoptr(GsApp) app = NULL;
+	g_autoptr(GsAppList) list = gs_app_list_new ();
+	g_autoptr(GsPluginJob) refine_job = NULL;
+
+	g_return_if_fail (GS_IS_PLUGIN_LOADER (plugin_loader));
+	g_return_if_fail (unique_id != NULL);
+	g_return_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable));
+
+	task = g_task_new (plugin_loader, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_plugin_loader_app_create_async);
+	g_task_set_task_data (task, g_strdup (unique_id), g_free);
+
+	/* use the plugin loader to convert a wildcard app */
+	app = gs_app_new (NULL);
+	gs_app_add_quirk (app, GS_APP_QUIRK_IS_WILDCARD);
+	gs_app_set_from_unique_id (app, unique_id, AS_COMPONENT_KIND_UNKNOWN);
+	gs_app_list_add (list, app);
+
+	/* Refine the wildcard app. */
+	refine_job = gs_plugin_job_refine_new (list, GS_PLUGIN_REFINE_FLAGS_REQUIRE_ID | GS_PLUGIN_REFINE_FLAGS_DISABLE_FILTERING);
+	gs_plugin_loader_job_process_async (plugin_loader, refine_job,
+					    cancellable,
+					    app_create_cb,
+					    g_steal_pointer (&task));
+}
+
+static void
+app_create_cb (GObject      *source_object,
+               GAsyncResult *result,
+               gpointer      user_data)
+{
+	g_autoptr(GTask) task = g_steal_pointer (&user_data);
+	GsPluginLoader *plugin_loader = GS_PLUGIN_LOADER (g_task_get_source_object (task));
+	const gchar *unique_id = g_task_get_task_data (task);
+	g_autoptr(GsAppList) list = NULL;
+	g_autoptr(GError) local_error = NULL;
+
+	list = gs_plugin_loader_job_process_finish (plugin_loader, result, &local_error);
+	if (list == NULL) {
+		g_prefix_error (&local_error, "Failed to refine '%s': ", unique_id);
+		g_task_return_error (task, g_steal_pointer (&local_error));
+		return;
+	}
+
+	/* return the matching GsApp */
+	for (guint i = 0; i < gs_app_list_length (list); i++) {
+		GsApp *app_tmp = gs_app_list_index (list, i);
+		if (g_strcmp0 (unique_id, gs_app_get_unique_id (app_tmp)) == 0) {
+			g_task_return_pointer (task, g_object_ref (app_tmp), g_object_unref);
+			return;
+		}
+	}
+
+	/* return the first returned app that's not a wildcard */
+	for (guint i = 0; i < gs_app_list_length (list); i++) {
+		GsApp *app_tmp = gs_app_list_index (list, i);
+		if (!gs_app_has_quirk (app_tmp, GS_APP_QUIRK_IS_WILDCARD)) {
+			g_debug ("returning imperfect match: %s != %s",
+				 unique_id, gs_app_get_unique_id (app_tmp));
+			g_task_return_pointer (task, g_object_ref (app_tmp), g_object_unref);
+			return;
+		}
+	}
+
+	/* does not exist */
+	g_task_return_new_error (task,
+				 GS_PLUGIN_ERROR,
+				 GS_PLUGIN_ERROR_FAILED,
+				 "Failed to create an app for '%s'", unique_id);
+}
+
+/**
+ * gs_plugin_loader_app_create_finish:
+ * @plugin_loader: a #GsPluginLoader
+ * @res: a #GAsyncResult
+ * @error: A #GError, or %NULL
+ *
+ * Finishes call to gs_plugin_loader_app_create_async().
+ *
+ * Returns: (transfer full): a #GsApp, or %NULL on error.
+ *
+ * Since: 41
+ **/
+GsApp *
+gs_plugin_loader_app_create_finish (GsPluginLoader *plugin_loader,
+				    GAsyncResult *res,
+				    GError **error)
+{
+	GsApp *app;
+
+	g_return_val_if_fail (GS_IS_PLUGIN_LOADER (plugin_loader), NULL);
+	g_return_val_if_fail (G_IS_TASK (res), NULL);
+	g_return_val_if_fail (g_task_is_valid (res, plugin_loader), NULL);
+	g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+
+	app = g_task_propagate_pointer (G_TASK (res), error);
+	gs_utils_error_convert_gio (error);
+	return app;
+}
+
+/**
+ * gs_plugin_loader_get_system_app_async:
+ * @plugin_loader: a #GsPluginLoader
+ * @cancellable: a #GCancellable, or %NULL
+ * @callback: function to call when complete
+ * @user_data: user data to pass to @callback
+ *
+ * Get the application that represents the currently installed OS
+ * asynchronously. Finish the call with gs_plugin_loader_get_system_app_finish().
+ *
+ * Since: 41
+ **/
+void
+gs_plugin_loader_get_system_app_async (GsPluginLoader *plugin_loader,
+				       GCancellable *cancellable,
+				       GAsyncReadyCallback callback,
+				       gpointer user_data)
+{
+	gs_plugin_loader_app_create_async (plugin_loader, "*/*/*/system/*", cancellable, callback, user_data);
+}
+
+/**
+ * gs_plugin_loader_get_system_app_finish:
+ * @plugin_loader: a #GsPluginLoader
+ * @res: a #GAsyncResult
+ * @error: A #GError, or %NULL
+ *
+ * Finishes call to gs_plugin_loader_get_system_app_async().
+ *
+ * Returns: (transfer full): a #GsApp, which represents
+ *    the currently installed OS, or %NULL on error.
+ *
+ * Since: 41
+ **/
+GsApp *
+gs_plugin_loader_get_system_app_finish (GsPluginLoader *plugin_loader,
+					GAsyncResult *res,
+					GError **error)
+{
+	return gs_plugin_loader_app_create_finish (plugin_loader, res, error);
+}
+
+/**
+ * gs_plugin_loader_get_odrs_provider:
+ * @plugin_loader: a #GsPluginLoader
+ *
+ * Get the singleton #GsOdrsProvider which provides access to ratings and
+ * reviews data from ODRS.
+ *
+ * Returns: (transfer none) (nullable): a #GsOdrsProvider, or %NULL if disabled
+ * Since: 41
+ */
+GsOdrsProvider *
+gs_plugin_loader_get_odrs_provider (GsPluginLoader *plugin_loader)
+{
+	g_return_val_if_fail (GS_IS_PLUGIN_LOADER (plugin_loader), NULL);
+
+	return plugin_loader->odrs_provider;
+}
+
+/**
+ * gs_plugin_loader_set_max_parallel_ops:
+ * @plugin_loader: a #GsPluginLoader
+ * @max_ops: the maximum number of parallel operations
+ *
+ * Sets the number of maximum number of queued operations (install/update/upgrade-download)
+ * to be processed at a time. If @max_ops is 0, then it will set the default maximum number.
+ */
+void
+gs_plugin_loader_set_max_parallel_ops (GsPluginLoader *plugin_loader,
+				       guint max_ops)
+{
+	g_autoptr(GError) error = NULL;
+	if (max_ops == 0)
+		max_ops = get_max_parallel_ops ();
+	if (!g_thread_pool_set_max_threads (plugin_loader->queued_ops_pool, max_ops, &error))
+		g_warning ("Failed to set the maximum number of ops in parallel: %s",
+			   error->message);
+}
+
+/**
+ * gs_plugin_loader_get_category_manager:
+ * @plugin_loader: a #GsPluginLoader
+ *
+ * Get the category manager singleton.
+ *
+ * Returns: (transfer none): a category manager
+ * Since: 40
+ */
+GsCategoryManager *
+gs_plugin_loader_get_category_manager (GsPluginLoader *plugin_loader)
+{
+	g_return_val_if_fail (GS_IS_PLUGIN_LOADER (plugin_loader), NULL);
+
+	return plugin_loader->category_manager;
+}
+
+/**
+ * gs_plugin_loader_emit_updates_changed:
+ * @self: a #GsPluginLoader
+ *
+ * Emits the #GsPluginLoader:updates-changed signal in the nearest
+ * idle in the main thread.
+ *
+ * Since: 43
+ **/
+void
+gs_plugin_loader_emit_updates_changed (GsPluginLoader *self)
+{
+	g_return_if_fail (GS_IS_PLUGIN_LOADER (self));
+
+	if (self->updates_changed_id != 0)
+		g_source_remove (self->updates_changed_id);
+
+	self->updates_changed_id =
+		g_idle_add_full (G_PRIORITY_HIGH_IDLE,
+				 gs_plugin_loader_job_updates_changed_delay_cb,
+				 g_object_ref (self), g_object_unref);
+}
diff --git a/lib/gs-plugin-loader.h b/lib/gs-plugin-loader.h
new file mode 100644
index 0000000..93a44d6
--- /dev/null
+++ b/lib/gs-plugin-loader.h
@@ -0,0 +1,122 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2007-2017 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2015-2020 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib-object.h>
+
+#include "gs-app.h"
+#include "gs-category.h"
+#include "gs-category-manager.h"
+#include "gs-odrs-provider.h"
+#include "gs-plugin-event.h"
+#include "gs-plugin.h"
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_PLUGIN_LOADER		(gs_plugin_loader_get_type ())
+G_DECLARE_FINAL_TYPE (GsPluginLoader, gs_plugin_loader, GS, PLUGIN_LOADER, GObject)
+
+#include "gs-plugin-job.h"
+
+GsPluginLoader	*gs_plugin_loader_new			(GDBusConnection *session_bus_connection,
+							 GDBusConnection *system_bus_connection);
+void		 gs_plugin_loader_job_process_async	(GsPluginLoader	*plugin_loader,
+							 GsPluginJob	*plugin_job,
+							 GCancellable	*cancellable,
+							 GAsyncReadyCallback callback,
+							 gpointer	 user_data);
+GsAppList	*gs_plugin_loader_job_process_finish	(GsPluginLoader	*plugin_loader,
+							 GAsyncResult	*res,
+							 GError		**error);
+gboolean	 gs_plugin_loader_job_action_finish	(GsPluginLoader	*plugin_loader,
+							 GAsyncResult	*res,
+							 GError		**error);
+void		 gs_plugin_loader_setup_async		(GsPluginLoader	*plugin_loader,
+							 const gchar * const *allowlist,
+							 const gchar * const *blocklist,
+							 GCancellable	*cancellable,
+							 GAsyncReadyCallback callback,
+							 gpointer	 user_data);
+gboolean	 gs_plugin_loader_setup_finish		(GsPluginLoader	*plugin_loader,
+							 GAsyncResult	*result,
+							 GError		**error);
+
+void		 gs_plugin_loader_shutdown		(GsPluginLoader	*plugin_loader,
+							 GCancellable	*cancellable);
+
+void		 gs_plugin_loader_dump_state		(GsPluginLoader	*plugin_loader);
+gboolean	 gs_plugin_loader_get_enabled		(GsPluginLoader	*plugin_loader,
+							 const gchar	*plugin_name);
+void		 gs_plugin_loader_add_location		(GsPluginLoader	*plugin_loader,
+							 const gchar	*location);
+guint		 gs_plugin_loader_get_scale		(GsPluginLoader	*plugin_loader);
+void		 gs_plugin_loader_set_scale		(GsPluginLoader	*plugin_loader,
+							 guint		 scale);
+GsAppList	*gs_plugin_loader_get_pending		(GsPluginLoader	*plugin_loader);
+gboolean	 gs_plugin_loader_get_allow_updates	(GsPluginLoader	*plugin_loader);
+gboolean	 gs_plugin_loader_get_network_available	(GsPluginLoader *plugin_loader);
+gboolean	 gs_plugin_loader_get_network_metered	(GsPluginLoader *plugin_loader);
+gboolean	 gs_plugin_loader_get_plugin_supported	(GsPluginLoader	*plugin_loader,
+							 const gchar	*function_name);
+
+GPtrArray	*gs_plugin_loader_get_plugins		(GsPluginLoader	*plugin_loader);
+
+void		 gs_plugin_loader_add_event		(GsPluginLoader *plugin_loader,
+							 GsPluginEvent	*event);
+GPtrArray	*gs_plugin_loader_get_events		(GsPluginLoader	*plugin_loader);
+GsPluginEvent	*gs_plugin_loader_get_event_default	(GsPluginLoader	*plugin_loader);
+void		 gs_plugin_loader_remove_events		(GsPluginLoader	*plugin_loader);
+
+void		 gs_plugin_loader_app_create_async	(GsPluginLoader	*plugin_loader,
+							 const gchar	*unique_id,
+							 GCancellable	*cancellable,
+							 GAsyncReadyCallback callback,
+							 gpointer	 user_data);
+GsApp		*gs_plugin_loader_app_create_finish	(GsPluginLoader	*plugin_loader,
+							 GAsyncResult	*res,
+							 GError		**error);
+void		 gs_plugin_loader_get_system_app_async	(GsPluginLoader	*plugin_loader,
+							 GCancellable	*cancellable,
+							 GAsyncReadyCallback callback,
+							 gpointer	 user_data);
+GsApp		*gs_plugin_loader_get_system_app_finish	(GsPluginLoader	*plugin_loader,
+							 GAsyncResult	*res,
+							 GError		**error);
+GsOdrsProvider	*gs_plugin_loader_get_odrs_provider	(GsPluginLoader	*plugin_loader);
+
+/* only useful from the self tests */
+void		 gs_plugin_loader_clear_caches		(GsPluginLoader	*plugin_loader);
+GsPlugin	*gs_plugin_loader_find_plugin		(GsPluginLoader	*plugin_loader,
+							 const gchar	*plugin_name);
+void            gs_plugin_loader_set_max_parallel_ops  (GsPluginLoader *plugin_loader,
+                                                        guint           max_ops);
+
+GsCategoryManager *gs_plugin_loader_get_category_manager (GsPluginLoader *plugin_loader);
+void		 gs_plugin_loader_claim_error		(GsPluginLoader *plugin_loader,
+							 GsPlugin *plugin,
+							 GsPluginAction action,
+							 GsApp *app,
+							 gboolean interactive,
+							 const GError *error);
+void		 gs_plugin_loader_claim_job_error	(GsPluginLoader *plugin_loader,
+							 GsPlugin *plugin,
+							 GsPluginJob *job,
+							 const GError *error);
+
+gboolean	 gs_plugin_loader_app_is_valid		(GsApp *app,
+							 GsPluginRefineFlags flags);
+gboolean	 gs_plugin_loader_app_is_compatible	(GsPluginLoader *plugin_loader,
+							 GsApp *app);
+
+void		 gs_plugin_loader_run_adopt		(GsPluginLoader *plugin_loader,
+							 GsAppList *list);
+void		 gs_plugin_loader_emit_updates_changed	(GsPluginLoader *self);
+
+G_END_DECLS
diff --git a/lib/gs-plugin-private.h b/lib/gs-plugin-private.h
new file mode 100644
index 0000000..3a44856
--- /dev/null
+++ b/lib/gs-plugin-private.h
@@ -0,0 +1,57 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2016 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <gio/gio.h>
+#include <glib-object.h>
+#include <gmodule.h>
+
+#include "gs-plugin.h"
+
+G_BEGIN_DECLS
+
+GsPlugin	*gs_plugin_new				(GDBusConnection *session_bus_connection,
+							 GDBusConnection *system_bus_connection);
+GsPlugin	*gs_plugin_create			(const gchar	*filename,
+							 GDBusConnection *session_bus_connection,
+							 GDBusConnection *system_bus_connection,
+							 GError		**error);
+const gchar	*gs_plugin_error_to_string		(GsPluginError	 error);
+const gchar	*gs_plugin_action_to_string		(GsPluginAction	 action);
+GsPluginAction	 gs_plugin_action_from_string		(const gchar	*action);
+const gchar	*gs_plugin_action_to_function_name	(GsPluginAction	 action);
+
+void		 gs_plugin_set_scale			(GsPlugin	*plugin,
+							 guint		 scale);
+guint		 gs_plugin_get_order			(GsPlugin	*plugin);
+void		 gs_plugin_set_order			(GsPlugin	*plugin,
+							 guint		 order);
+guint		 gs_plugin_get_priority			(GsPlugin	*plugin);
+void		 gs_plugin_set_priority			(GsPlugin	*plugin,
+							 guint		 priority);
+void		 gs_plugin_set_name			(GsPlugin	*plugin,
+							 const gchar	*name);
+void		 gs_plugin_set_language			(GsPlugin	*plugin,
+							 const gchar	*language);
+void		 gs_plugin_set_auth_array		(GsPlugin	*plugin,
+							 GPtrArray	*auth_array);
+GPtrArray	*gs_plugin_get_rules			(GsPlugin	*plugin,
+							 GsPluginRule	 rule);
+gpointer	 gs_plugin_get_symbol			(GsPlugin	*plugin,
+							 const gchar	*function_name);
+void		 gs_plugin_interactive_inc		(GsPlugin	*plugin);
+void		 gs_plugin_interactive_dec		(GsPlugin	*plugin);
+gchar		*gs_plugin_refine_flags_to_string	(GsPluginRefineFlags refine_flags);
+void		 gs_plugin_set_network_monitor		(GsPlugin		*plugin,
+							 GNetworkMonitor	*monitor);
+
+GDBusConnection	*gs_plugin_get_session_bus_connection	(GsPlugin	*self);
+GDBusConnection	*gs_plugin_get_system_bus_connection	(GsPlugin	*self);
+
+G_END_DECLS
diff --git a/lib/gs-plugin-types.h b/lib/gs-plugin-types.h
new file mode 100644
index 0000000..59504be
--- /dev/null
+++ b/lib/gs-plugin-types.h
@@ -0,0 +1,319 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2012-2018 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib-object.h>
+
+G_BEGIN_DECLS
+
+/**
+ * GsPluginStatus:
+ * @GS_PLUGIN_STATUS_UNKNOWN:		Unknown status
+ * @GS_PLUGIN_STATUS_WAITING:		Waiting
+ * @GS_PLUGIN_STATUS_FINISHED:		Finished
+ * @GS_PLUGIN_STATUS_SETUP:		Setup in progress
+ * @GS_PLUGIN_STATUS_DOWNLOADING:	Downloading in progress
+ * @GS_PLUGIN_STATUS_QUERYING:		Querying in progress
+ * @GS_PLUGIN_STATUS_INSTALLING:	Installing in progress
+ * @GS_PLUGIN_STATUS_REMOVING:		Removing in progress
+ *
+ * The status of the plugin.
+ **/
+typedef enum {
+	GS_PLUGIN_STATUS_UNKNOWN,
+	GS_PLUGIN_STATUS_WAITING,
+	GS_PLUGIN_STATUS_FINISHED,
+	GS_PLUGIN_STATUS_SETUP,
+	GS_PLUGIN_STATUS_DOWNLOADING,
+	GS_PLUGIN_STATUS_QUERYING,
+	GS_PLUGIN_STATUS_INSTALLING,
+	GS_PLUGIN_STATUS_REMOVING,
+	GS_PLUGIN_STATUS_LAST  /*< skip >*/
+} GsPluginStatus;
+
+/**
+ * GsPluginFlags:
+ * @GS_PLUGIN_FLAGS_NONE:		No flags set
+ * @GS_PLUGIN_FLAGS_INTERACTIVE:	User initiated the job
+ *
+ * The flags for the plugin at this point in time.
+ **/
+typedef enum {
+	GS_PLUGIN_FLAGS_NONE = 0,
+	GS_PLUGIN_FLAGS_INTERACTIVE = 1 << 4,
+} GsPluginFlags;
+
+/**
+ * GsPluginError:
+ * @GS_PLUGIN_ERROR_FAILED:			Generic failure
+ * @GS_PLUGIN_ERROR_NOT_SUPPORTED:		Action not supported
+ * @GS_PLUGIN_ERROR_CANCELLED:			Action was cancelled
+ * @GS_PLUGIN_ERROR_NO_NETWORK:			No network connection available
+ * @GS_PLUGIN_ERROR_NO_SECURITY:		Security policy forbid action
+ * @GS_PLUGIN_ERROR_NO_SPACE:			No disk space to allow action
+ * @GS_PLUGIN_ERROR_AUTH_REQUIRED:		Authentication was required
+ * @GS_PLUGIN_ERROR_AUTH_INVALID:		Provided authentication was invalid
+ * @GS_PLUGIN_ERROR_PLUGIN_DEPSOLVE_FAILED:	The plugins installed are incompatible
+ * @GS_PLUGIN_ERROR_DOWNLOAD_FAILED:		The download action failed
+ * @GS_PLUGIN_ERROR_WRITE_FAILED:		The save-to-disk failed
+ * @GS_PLUGIN_ERROR_INVALID_FORMAT:		The data format is invalid
+ * @GS_PLUGIN_ERROR_DELETE_FAILED:		The delete action failed
+ * @GS_PLUGIN_ERROR_RESTART_REQUIRED:		A restart is required
+ * @GS_PLUGIN_ERROR_AC_POWER_REQUIRED:		AC power is required
+ * @GS_PLUGIN_ERROR_TIMED_OUT:			The job timed out
+ * @GS_PLUGIN_ERROR_BATTERY_LEVEL_TOO_LOW:	The system battery level is too low
+ *
+ * The failure error types.
+ **/
+typedef enum {
+	GS_PLUGIN_ERROR_FAILED,
+	GS_PLUGIN_ERROR_NOT_SUPPORTED,
+	GS_PLUGIN_ERROR_CANCELLED,
+	GS_PLUGIN_ERROR_NO_NETWORK,
+	GS_PLUGIN_ERROR_NO_SECURITY,
+	GS_PLUGIN_ERROR_NO_SPACE,
+	GS_PLUGIN_ERROR_AUTH_REQUIRED,
+	GS_PLUGIN_ERROR_AUTH_INVALID,
+	GS_PLUGIN_ERROR_PLUGIN_DEPSOLVE_FAILED,
+	GS_PLUGIN_ERROR_DOWNLOAD_FAILED,
+	GS_PLUGIN_ERROR_WRITE_FAILED,
+	GS_PLUGIN_ERROR_INVALID_FORMAT,
+	GS_PLUGIN_ERROR_DELETE_FAILED,
+	GS_PLUGIN_ERROR_RESTART_REQUIRED,
+	GS_PLUGIN_ERROR_AC_POWER_REQUIRED,
+	GS_PLUGIN_ERROR_TIMED_OUT,
+	GS_PLUGIN_ERROR_BATTERY_LEVEL_TOO_LOW,
+	GS_PLUGIN_ERROR_LAST  /*< skip >*/
+} GsPluginError;
+
+/**
+ * GsPluginRefineFlags:
+ * @GS_PLUGIN_REFINE_FLAGS_NONE:			No explicit flags set
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_ID:			Require the app’s ID; this is the minimum possible requirement
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_LICENSE:		Require the license
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_URL:			Require the URL
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_DESCRIPTION:		Require the long description
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_SIZE:		Require the installed and download sizes
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_RATING:		Require the rating
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_VERSION:		Require the version
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_HISTORY:		Require the history
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_SETUP_ACTION:	Require enough to install or remove the package
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_UPDATE_DETAILS:	Require update details
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN:		Require the origin
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_RELATED:		Require related packages
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_ADDONS:		Require available addons
+ * @GS_PLUGIN_REFINE_FLAGS_ALLOW_PACKAGES:		Allow packages to be returned
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_UPDATE_SEVERITY:	Require update severity
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_UPGRADE_REMOVED:	Require distro upgrades
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_PROVENANCE:		Require the provenance
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_REVIEWS:		Require user-reviews
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_REVIEW_RATINGS:	Require user-ratings
+ * @GS_PLUGIN_REFINE_FLAGS_DISABLE_FILTERING:		Normally the results of a refine are
+ * 	filtered to remove non-valid apps; if this flag is set, that won’t happen.
+ * 	This is intended to be used by internal #GsPluginLoader code. (Since: 42)
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_ICON:		Require the icon to be loaded
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_PERMISSIONS:		Require the needed permissions
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN_HOSTNAME:	Require the origin hostname
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN_UI:		Require the origin for UI
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_RUNTIME:		Require the runtime
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_SCREENSHOTS:		Require screenshot information
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_CATEGORIES:		Require categories
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_PROJECT_GROUP:	Require project group
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_DEVELOPER_NAME:	Require developer name
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_KUDOS:		Require kudos
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_CONTENT_RATING:	Require content rating
+ * @GS_PLUGIN_REFINE_FLAGS_REQUIRE_SIZE_DATA:		Require user and cache data sizes (Since: 41)
+ * @GS_PLUGIN_REFINE_FLAGS_MASK:			All flags (Since: 40)
+ *
+ * The refine flags.
+ **/
+typedef enum {
+	GS_PLUGIN_REFINE_FLAGS_NONE			= 0,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_ID		= 1 << 0,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_LICENSE		= 1 << 1,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_URL		= 1 << 2,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_DESCRIPTION	= 1 << 3,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_SIZE		= 1 << 4,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_RATING		= 1 << 5,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_VERSION		= 1 << 6,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_HISTORY		= 1 << 7,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_SETUP_ACTION	= 1 << 8,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_UPDATE_DETAILS	= 1 << 9,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN		= 1 << 10,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_RELATED		= 1 << 11,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_SIZE_DATA	= 1 << 12,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_ADDONS		= 1 << 13,
+	GS_PLUGIN_REFINE_FLAGS_ALLOW_PACKAGES		= 1 << 14, /* TODO: move to request */
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_UPDATE_SEVERITY	= 1 << 15,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_UPGRADE_REMOVED	= 1 << 16,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_PROVENANCE	= 1 << 17,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_REVIEWS		= 1 << 18,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_REVIEW_RATINGS	= 1 << 19,
+	GS_PLUGIN_REFINE_FLAGS_DISABLE_FILTERING	= 1 << 20,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_ICON		= 1 << 21,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_PERMISSIONS	= 1 << 22,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN_HOSTNAME	= 1 << 23,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN_UI	= 1 << 24,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_RUNTIME		= 1 << 25,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_SCREENSHOTS	= 1 << 26,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_CATEGORIES	= 1 << 27,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_PROJECT_GROUP	= 1 << 28,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_DEVELOPER_NAME	= 1 << 29,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_KUDOS		= 1 << 30,
+	GS_PLUGIN_REFINE_FLAGS_REQUIRE_CONTENT_RATING	= 1 << 31,
+	GS_PLUGIN_REFINE_FLAGS_MASK			= ~0,
+} GsPluginRefineFlags;
+
+/**
+ * GsPluginListAppsFlags:
+ * @GS_PLUGIN_LIST_APPS_FLAGS_NONE: No flags set.
+ * @GS_PLUGIN_LIST_APPS_FLAGS_INTERACTIVE: User initiated the job.
+ *
+ * Flags for an operation to list apps matching a given query.
+ *
+ * Since: 43
+ */
+typedef enum {
+	GS_PLUGIN_LIST_APPS_FLAGS_NONE = 0,
+	GS_PLUGIN_LIST_APPS_FLAGS_INTERACTIVE = 1 << 0,
+} GsPluginListAppsFlags;
+
+/**
+ * GsPluginRefineCategoriesFlags:
+ * @GS_PLUGIN_REFINE_CATEGORIES_FLAGS_NONE: No flags set.
+ * @GS_PLUGIN_REFINE_CATEGORIES_FLAGS_INTERACTIVE: User initiated the job.
+ * @GS_PLUGIN_REFINE_CATEGORIES_FLAGS_SIZE: Work out the number of apps in each category.
+ *
+ * Flags for an operation to refine categories.
+ *
+ * Since: 43
+ */
+typedef enum {
+	GS_PLUGIN_REFINE_CATEGORIES_FLAGS_NONE = 0,
+	GS_PLUGIN_REFINE_CATEGORIES_FLAGS_INTERACTIVE = 1 << 0,
+	GS_PLUGIN_REFINE_CATEGORIES_FLAGS_SIZE = 1 << 1,
+} GsPluginRefineCategoriesFlags;
+
+/**
+ * GsPluginRefreshMetadataFlags:
+ * @GS_PLUGIN_REFRESH_METADATA_FLAGS_NONE: No flags set.
+ * @GS_PLUGIN_REFRESH_METADATA_FLAGS_INTERACTIVE: User initiated the job.
+ *
+ * Flags for an operation to refresh metadata.
+ *
+ * Since: 42
+ */
+typedef enum {
+	GS_PLUGIN_REFRESH_METADATA_FLAGS_NONE = 0,
+	GS_PLUGIN_REFRESH_METADATA_FLAGS_INTERACTIVE = 1 << 0,
+} GsPluginRefreshMetadataFlags;
+
+/**
+ * GsPluginListDistroUpgradesFlags:
+ * @GS_PLUGIN_LIST_DISTRO_UPGRADES_FLAGS_NONE: No flags set.
+ * @GS_PLUGIN_LIST_DISTRO_UPGRADES_FLAGS_INTERACTIVE: User initiated the job.
+ *
+ * Flags for an operation to list available distro upgrades.
+ *
+ * Since: 42
+ */
+typedef enum {
+	GS_PLUGIN_LIST_DISTRO_UPGRADES_FLAGS_NONE = 0,
+	GS_PLUGIN_LIST_DISTRO_UPGRADES_FLAGS_INTERACTIVE = 1 << 0,
+} GsPluginListDistroUpgradesFlags;
+
+/**
+ * GsPluginManageRepositoryFlags:
+ * @GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_NONE: No flags set.
+ * @GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_INTERACTIVE: User initiated the job.
+ * @GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_INSTALL: Install the repository.
+ * @GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_REMOVE: Remove the repository.
+ * @GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_ENABLE: Enable the repository.
+ * @GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_DISABLE: Disable the repository.
+ *
+ * Flags for an operation on a repository.
+ *
+ * Since: 42
+ */
+typedef enum {
+	GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_NONE		= 0,
+	GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_INTERACTIVE	= 1 << 0,
+	GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_INSTALL	= 1 << 1,
+	GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_REMOVE	= 1 << 2,
+	GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_ENABLE	= 1 << 3,
+	GS_PLUGIN_MANAGE_REPOSITORY_FLAGS_DISABLE	= 1 << 4,
+} GsPluginManageRepositoryFlags;
+
+/**
+ * GsPluginRule:
+ * @GS_PLUGIN_RULE_CONFLICTS:		The plugin conflicts with another
+ * @GS_PLUGIN_RULE_RUN_AFTER:		Order the plugin after another
+ * @GS_PLUGIN_RULE_RUN_BEFORE:		Order the plugin before another
+ * @GS_PLUGIN_RULE_BETTER_THAN:		Results are better than another
+ *
+ * The rules used for ordering plugins.
+ * Plugins are expected to add rules in the init function for their #GsPlugin
+ * subclass.
+ **/
+typedef enum {
+	GS_PLUGIN_RULE_CONFLICTS,
+	GS_PLUGIN_RULE_RUN_AFTER,
+	GS_PLUGIN_RULE_RUN_BEFORE,
+	GS_PLUGIN_RULE_BETTER_THAN,
+	GS_PLUGIN_RULE_LAST  /*< skip >*/
+} GsPluginRule;
+
+/**
+ * GsPluginAction:
+ * @GS_PLUGIN_ACTION_UNKNOWN:			Action is unknown
+ * @GS_PLUGIN_ACTION_INSTALL:			Install an application
+ * @GS_PLUGIN_ACTION_REMOVE:			Remove an application
+ * @GS_PLUGIN_ACTION_UPDATE:			Update an application
+ * @GS_PLUGIN_ACTION_UPGRADE_DOWNLOAD:		Download a distro upgrade
+ * @GS_PLUGIN_ACTION_UPGRADE_TRIGGER:		Trigger a distro upgrade
+ * @GS_PLUGIN_ACTION_LAUNCH:			Launch an application
+ * @GS_PLUGIN_ACTION_UPDATE_CANCEL:		Cancel the update
+ * @GS_PLUGIN_ACTION_GET_UPDATES:		Get the list of updates
+ * @GS_PLUGIN_ACTION_GET_SOURCES:		Get the list of sources
+ * @GS_PLUGIN_ACTION_FILE_TO_APP:		Convert the file to an application
+ * @GS_PLUGIN_ACTION_URL_TO_APP:		Convert the URI to an application
+ * @GS_PLUGIN_ACTION_GET_UPDATES_HISTORICAL:    Get the list of historical updates
+ * @GS_PLUGIN_ACTION_DOWNLOAD:			Download an application
+ * @GS_PLUGIN_ACTION_GET_LANGPACKS:		Get appropriate language pack
+ * @GS_PLUGIN_ACTION_INSTALL_REPO:		Install a repository (Since: 41)
+ * @GS_PLUGIN_ACTION_REMOVE_REPO:		Remove a repository (Since: 41)
+ * @GS_PLUGIN_ACTION_ENABLE_REPO:		Enable a repository (Since: 41)
+ * @GS_PLUGIN_ACTION_DISABLE_REPO:		Disable a repository (Since: 41)
+ *
+ * The plugin action.
+ **/
+typedef enum {
+	GS_PLUGIN_ACTION_UNKNOWN,
+	GS_PLUGIN_ACTION_INSTALL,
+	GS_PLUGIN_ACTION_REMOVE,
+	GS_PLUGIN_ACTION_UPDATE,
+	GS_PLUGIN_ACTION_UPGRADE_DOWNLOAD,
+	GS_PLUGIN_ACTION_UPGRADE_TRIGGER,
+	GS_PLUGIN_ACTION_LAUNCH,
+	GS_PLUGIN_ACTION_UPDATE_CANCEL,
+	GS_PLUGIN_ACTION_GET_UPDATES,
+	GS_PLUGIN_ACTION_GET_SOURCES,
+	GS_PLUGIN_ACTION_FILE_TO_APP,
+	GS_PLUGIN_ACTION_URL_TO_APP,
+	GS_PLUGIN_ACTION_GET_UPDATES_HISTORICAL,
+	GS_PLUGIN_ACTION_DOWNLOAD,
+	GS_PLUGIN_ACTION_GET_LANGPACKS,
+	GS_PLUGIN_ACTION_INSTALL_REPO,
+	GS_PLUGIN_ACTION_REMOVE_REPO,
+	GS_PLUGIN_ACTION_ENABLE_REPO,
+	GS_PLUGIN_ACTION_DISABLE_REPO,
+	GS_PLUGIN_ACTION_LAST  /*< skip >*/
+} GsPluginAction;
+
+G_END_DECLS
diff --git a/lib/gs-plugin-vfuncs.h b/lib/gs-plugin-vfuncs.h
new file mode 100644
index 0000000..39093f5
--- /dev/null
+++ b/lib/gs-plugin-vfuncs.h
@@ -0,0 +1,429 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2012-2017 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+/**
+ * SECTION:gs-plugin-vfuncs
+ * @title: GsPlugin Exports
+ * @include: gnome-software.h
+ * @stability: Unstable
+ * @short_description: Vfuncs that plugins can implement
+ */
+
+#include <appstream.h>
+#include <glib-object.h>
+#include <gmodule.h>
+#include <gio/gio.h>
+#include <libsoup/soup.h>
+
+#include "gs-app.h"
+#include "gs-app-list.h"
+#include "gs-category.h"
+
+G_BEGIN_DECLS
+
+/**
+ * gs_plugin_query_type:
+ *
+ * Returns the #GType for a subclass of #GsPlugin provided by this plugin
+ * module. It should not do any other computation.
+ *
+ * The init function for that type should initialize the plugin. If the plugin
+ * should not be run then gs_plugin_set_enabled() should be called from the
+ * init function.
+ *
+ * NOTE: Do not do any failable actions in the plugin class’ init function; use
+ * #GsPluginClass.setup_async instead.
+ *
+ * Since: 42
+ */
+GType		 gs_plugin_query_type			(void);
+
+/**
+ * gs_plugin_adopt_app:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp
+ *
+ * Called when an #GsApp has not been claimed (i.e. a management plugin has not
+ * been set).
+ *
+ * A claimed application means other plugins will not try to perform actions
+ * such as install, remove or update. Most applications are claimed when they
+ * are created.
+ *
+ * If a plugin can adopt this application then it should call
+ * gs_app_set_management_plugin() on @app.
+ **/
+void		 gs_plugin_adopt_app			(GsPlugin	*plugin,
+							 GsApp		*app);
+
+/**
+ * gs_plugin_add_updates:
+ * @plugin: a #GsPlugin
+ * @list: a #GsAppList
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Get the list of updates.
+ *
+ * NOTE: Actually downloading the updates can be done in gs_plugin_download_app()
+ * or in gs_plugin_download().
+ *
+ * Plugins are expected to add new apps using gs_app_list_add().
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_add_updates			(GsPlugin	*plugin,
+							 GsAppList	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+/**
+ * gs_plugin_add_sources:
+ * @plugin: a #GsPlugin
+ * @list: a #GsAppList
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Get the list of sources, for example the repos listed in /etc/yum.repos.d
+ * or the remotes configured in flatpak.
+ *
+ * Plugins are expected to add new apps using gs_app_list_add() of type
+ * %AS_COMPONENT_KIND_REPOSITORY.
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_add_sources			(GsPlugin	*plugin,
+							 GsAppList	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+/**
+ * gs_plugin_add_updates_historical
+ * @plugin: a #GsPlugin
+ * @list: a #GsAppList
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Get the list of historical updates, i.e. the updates that have just been
+ * installed.
+ *
+ * Plugins are expected to add new apps using gs_app_list_add().
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_add_updates_historical	(GsPlugin	*plugin,
+							 GsAppList	*list,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+/**
+ * gs_plugin_launch:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Launch the specified application using a plugin-specific method.
+ * This is normally setting some environment or launching a specific binary.
+ *
+ * Plugins can simply use gs_plugin_app_launch() if no plugin-specific
+ * functionality is required.
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_launch			(GsPlugin	*plugin,
+							 GsApp		*app,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+/**
+ * gs_plugin_update_cancel:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Cancels the offline update of @app.
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_update_cancel		(GsPlugin	*plugin,
+							 GsApp		*app,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+/**
+ * gs_plugin_app_install:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Install the application.
+ *
+ * Plugins are expected to send progress notifications to the UI using
+ * gs_app_set_progress() using the passed in @app.
+ *
+ * All functions can block, but should sent progress notifications, e.g. using
+ * gs_app_set_progress() if they will take more than tens of milliseconds
+ * to complete.
+ *
+ * On failure the error message returned will usually only be shown on the
+ * console, but they can also be retrieved using gs_plugin_loader_get_events().
+ *
+ * NOTE: Once the action is complete, the plugin must set the new state of @app
+ * to %GS_APP_STATE_INSTALLED.
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_app_install			(GsPlugin	*plugin,
+							 GsApp		*app,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+/**
+ * gs_plugin_app_remove:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Remove the application.
+ *
+ * Plugins are expected to send progress notifications to the UI using
+ * gs_app_set_progress() using the passed in @app.
+ *
+ * All functions can block, but should sent progress notifications, e.g. using
+ * gs_app_set_progress() if they will take more than tens of milliseconds
+ * to complete.
+ *
+ * On failure the error message returned will usually only be shown on the
+ * console, but they can also be retrieved using gs_plugin_loader_get_events().
+ *
+ * NOTE: Once the action is complete, the plugin must set the new state of @app
+ * to %GS_APP_STATE_AVAILABLE or %GS_APP_STATE_UNKNOWN if not known.
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_app_remove			(GsPlugin	*plugin,
+							 GsApp		*app,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+/**
+ * gs_plugin_update_app:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Update the application live.
+ *
+ * Plugins are expected to send progress notifications to the UI using
+ * gs_app_set_progress() using the passed in @app.
+ *
+ * All functions can block, but should sent progress notifications, e.g. using
+ * gs_app_set_progress() if they will take more than tens of milliseconds
+ * to complete.
+ *
+ * On failure the error message returned will usually only be shown on the
+ * console, but they can also be retrieved using gs_plugin_loader_get_events().
+ *
+ * NOTE: Once the action is complete, the plugin must set the new state of @app
+ * to %GS_APP_STATE_INSTALLED or %GS_APP_STATE_UNKNOWN if not known.
+ *
+ * If %GS_APP_QUIRK_IS_PROXY is set on the application then the actual #GsApp
+ * set in @app will be the related application of the parent. Plugins do not
+ * need to manually iterate on the related list of applications.
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_update_app			(GsPlugin	*plugin,
+							 GsApp		*app,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+/**
+ * gs_plugin_download_app:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Downloads the application and any dependencies ready to be installed or
+ * updated.
+ *
+ * Plugins are expected to schedule downloads using the system download
+ * scheduler if appropriate (if the download is not guaranteed to be under a few
+ * hundred kilobytes, for example), so that the user’s metered data preferences
+ * are honoured.
+ *
+ * Plugins are expected to send progress notifications to the UI using
+ * gs_app_set_progress() using the passed in @app.
+ *
+ * All functions can block, but should sent progress notifications, e.g. using
+ * gs_app_set_progress() if they will take more than tens of milliseconds
+ * to complete.
+ *
+ * If the @app is already downloaded, do not return an error and return %TRUE.
+ *
+ * On failure the error message returned will usually only be shown on the
+ * console, but they can also be retrieved using gs_plugin_loader_get_events().
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_download_app			(GsPlugin	*plugin,
+							 GsApp		*app,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+/**
+ * gs_plugin_download:
+ * @plugin: a #GsPlugin
+ * @apps: a #GsAppList
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Downloads a list of applications ready to be installed or updated.
+ *
+ * Plugins are expected to schedule downloads using the system download
+ * scheduler if appropriate (if the download is not guaranteed to be under a few
+ * hundred kilobytes, for example), so that the user’s metered data preferences
+ * are honoured.
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_download			(GsPlugin	*plugin,
+							 GsAppList	*apps,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+/**
+ * gs_plugin_app_upgrade_download:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp, with kind %AS_COMPONENT_KIND_OPERATING_SYSTEM
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Starts downloading a distribution upgrade in the background.
+ *
+ * All functions can block, but should sent progress notifications, e.g. using
+ * gs_app_set_progress() if they will take more than tens of milliseconds
+ * to complete.
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_app_upgrade_download		(GsPlugin	*plugin,
+							 GsApp		*app,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+/**
+ * gs_plugin_app_upgrade_trigger:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp, with kind %AS_COMPONENT_KIND_OPERATING_SYSTEM
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Triggers the distribution upgrade to be installed on next boot.
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_app_upgrade_trigger		(GsPlugin	*plugin,
+							 GsApp		*app,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+/**
+ * gs_plugin_file_to_app:
+ * @plugin: a #GsPlugin
+ * @list: a #GsAppList
+ * @file: a #GFile
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Converts a local file to a #GsApp. It's expected that only one plugin will
+ * match the mimetype of @file and that a single #GsApp will be in the returned
+ * list. If no plugins can handle the file, the list will be empty.
+ *
+ * For example, the PackageKit plugin can turn a .rpm file into a application
+ * of kind %AS_COMPONENT_KIND_UNKNOWN but that in some cases it will be further refined
+ * into a %AS_COMPONENT_KIND_DESKTOP_APP (with all the extra metadata) by the appstream
+ * plugin.
+ *
+ * Plugins are expected to add new apps using gs_app_list_add().
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_file_to_app			(GsPlugin	*plugin,
+							 GsAppList	*list,
+							 GFile		*file,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+/**
+ * gs_plugin_url_to_app:
+ * @plugin: a #GsPlugin
+ * @list: a #GsAppList
+ * @url: a #URL, e.g. "apt://gimp"
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Converts a URL to a #GsApp. It's expected that only one plugin will
+ * match the scheme of @url and that a single #GsApp will be in the returned
+ * list. If no plugins can handle the file, the list will be empty.
+ *
+ * For example, the apt plugin can turn apt://gimp into a application.
+ *
+ * Plugins are expected to add new apps using gs_app_list_add().
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_url_to_app			(GsPlugin	*plugin,
+							 GsAppList	*list,
+							 const gchar	*url,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+/**
+ * gs_plugin_update:
+ * @plugin: a #GsPlugin
+ * @apps: a #GsAppList
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Updates a list of applications, typically scheduling them for offline update.
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_update			(GsPlugin	*plugin,
+							 GsAppList	*apps,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+/**
+ * gs_plugin_add_langpacks:
+ * @plugin: a #GsPlugin
+ * @list: a #GsAppList
+ * @locale: a #LANGUAGE_CODE or #LOCALE, e.g. "ja" or "ja_JP"
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Returns a list of language packs, as per input language code or locale.
+ *
+ * Returns: %TRUE for success or if not relevant
+ **/
+gboolean	 gs_plugin_add_langpacks		(GsPlugin	*plugin,
+							 GsAppList	*list,
+							 const gchar    *locale,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+G_END_DECLS
diff --git a/lib/gs-plugin.c b/lib/gs-plugin.c
new file mode 100644
index 0000000..51e0f7e
--- /dev/null
+++ b/lib/gs-plugin.c
@@ -0,0 +1,2187 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2013-2016 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2014-2020 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-plugin
+ * @title: GsPlugin Helpers
+ * @include: gnome-software.h
+ * @stability: Unstable
+ * @short_description: Runtime-loaded modules providing functionality
+ *
+ * Plugins are modules that are loaded at runtime to provide information
+ * about requests and to service user actions like installing, removing
+ * and updating.
+ * This allows different distributions to pick and choose how the
+ * application installer gathers data.
+ *
+ * Plugins also have a priority system where the largest number gets
+ * run first. That means if one plugin requires some property or
+ * metadata set by another plugin then it **must** depend on the other
+ * plugin to be run in the correct order.
+ *
+ * As a general rule, try to make plugins as small and self-contained
+ * as possible and remember to cache as much data as possible for speed.
+ * Memory is cheap, time less so.
+ */
+
+#include "config.h"
+
+#include <gio/gdesktopappinfo.h>
+#include <gdk/gdk.h>
+#include <string.h>
+
+#include "gs-app-list-private.h"
+#include "gs-download-utils.h"
+#include "gs-enums.h"
+#include "gs-os-release.h"
+#include "gs-plugin-private.h"
+#include "gs-plugin.h"
+#include "gs-utils.h"
+
+typedef struct
+{
+	GHashTable		*cache;
+	GMutex			 cache_mutex;
+	GModule			*module;
+	GsPluginFlags		 flags;
+	GPtrArray		*rules[GS_PLUGIN_RULE_LAST];
+	GHashTable		*vfuncs;		/* string:pointer */
+	GMutex			 vfuncs_mutex;
+	gboolean		 enabled;
+	guint			 interactive_cnt;
+	GMutex			 interactive_mutex;
+	gchar			*language;		/* allow-none */
+	gchar			*name;
+	gchar			*appstream_id;
+	guint			 scale;
+	guint			 order;
+	guint			 priority;
+	guint			 timer_id;
+	GMutex			 timer_mutex;
+	GNetworkMonitor		*network_monitor;
+
+	GDBusConnection		*session_bus_connection;  /* (owned) (not nullable) */
+	GDBusConnection		*system_bus_connection;  /* (owned) (not nullable) */
+} GsPluginPrivate;
+
+G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (GsPlugin, gs_plugin, G_TYPE_OBJECT)
+
+G_DEFINE_QUARK (gs-plugin-error-quark, gs_plugin_error)
+
+typedef enum {
+	PROP_FLAGS = 1,
+	PROP_SESSION_BUS_CONNECTION,
+	PROP_SYSTEM_BUS_CONNECTION,
+} GsPluginProperty;
+
+static GParamSpec *obj_props[PROP_SYSTEM_BUS_CONNECTION + 1] = { NULL, };
+
+enum {
+	SIGNAL_UPDATES_CHANGED,
+	SIGNAL_STATUS_CHANGED,
+	SIGNAL_RELOAD,
+	SIGNAL_REPORT_EVENT,
+	SIGNAL_ALLOW_UPDATES,
+	SIGNAL_BASIC_AUTH_START,
+	SIGNAL_REPOSITORY_CHANGED,
+	SIGNAL_ASK_UNTRUSTED,
+	SIGNAL_LAST
+};
+
+static guint signals [SIGNAL_LAST] = { 0 };
+
+typedef const gchar	**(*GsPluginGetDepsFunc)	(GsPlugin	*plugin);
+
+/**
+ * gs_plugin_status_to_string:
+ * @status: a #GsPluginStatus, e.g. %GS_PLUGIN_STATUS_DOWNLOADING
+ *
+ * Converts the #GsPluginStatus enum to a string.
+ *
+ * Returns: the string representation, or "unknown"
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_plugin_status_to_string (GsPluginStatus status)
+{
+	if (status == GS_PLUGIN_STATUS_WAITING)
+		return "waiting";
+	if (status == GS_PLUGIN_STATUS_FINISHED)
+		return "finished";
+	if (status == GS_PLUGIN_STATUS_SETUP)
+		return "setup";
+	if (status == GS_PLUGIN_STATUS_DOWNLOADING)
+		return "downloading";
+	if (status == GS_PLUGIN_STATUS_QUERYING)
+		return "querying";
+	if (status == GS_PLUGIN_STATUS_INSTALLING)
+		return "installing";
+	if (status == GS_PLUGIN_STATUS_REMOVING)
+		return "removing";
+	return "unknown";
+}
+
+/**
+ * gs_plugin_set_name:
+ * @plugin: a #GsPlugin
+ * @name: a plugin name
+ *
+ * Sets the name of the plugin.
+ *
+ * Plugins are not required to set the plugin name as it is automatically set
+ * from the `.so` filename.
+ *
+ * Since: 3.26
+ **/
+void
+gs_plugin_set_name (GsPlugin *plugin, const gchar *name)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	if (priv->name != NULL)
+		g_free (priv->name);
+	priv->name = g_strdup (name);
+}
+
+/**
+ * gs_plugin_create:
+ * @filename: an absolute filename
+ * @session_bus_connection: (not nullable) (transfer none): a session bus
+ *   connection to use
+ * @system_bus_connection: (not nullable) (transfer none): a system bus
+ *   connection to use
+ * @error: a #GError, or %NULL
+ *
+ * Creates a new plugin from an external module.
+ *
+ * Returns: (transfer full): the #GsPlugin, or %NULL on error
+ *
+ * Since: 43
+ **/
+GsPlugin *
+gs_plugin_create (const gchar      *filename,
+                  GDBusConnection  *session_bus_connection,
+                  GDBusConnection  *system_bus_connection,
+                  GError          **error)
+{
+	GsPlugin *plugin = NULL;
+	GsPluginPrivate *priv;
+	g_autofree gchar *basename = NULL;
+	GModule *module = NULL;
+	GType (*query_type_function) (void) = NULL;
+	GType plugin_type;
+
+	/* get the plugin name from the basename */
+	basename = g_path_get_basename (filename);
+	if (!g_str_has_prefix (basename, "libgs_plugin_")) {
+		g_set_error (error,
+			     GS_PLUGIN_ERROR,
+			     GS_PLUGIN_ERROR_FAILED,
+			     "plugin filename has wrong prefix: %s",
+			     filename);
+		return NULL;
+	}
+	g_strdelimit (basename, ".", '\0');
+
+	/* create new plugin */
+	module = g_module_open (filename, 0);
+	if (module == NULL ||
+	    !g_module_symbol (module, "gs_plugin_query_type", (gpointer *) &query_type_function)) {
+		g_set_error (error,
+			     GS_PLUGIN_ERROR,
+			     GS_PLUGIN_ERROR_FAILED,
+			     "failed to open plugin %s: %s",
+			     filename, g_module_error ());
+		if (module != NULL)
+			g_module_close (module);
+		return NULL;
+	}
+
+	/* Make the module resident so it can’t be unloaded: without using a
+	 * full #GTypePlugin implementation for the modules, it’s not safe to
+	 * re-load a module and re-register its types with GObject, as that will
+	 * confuse the GType system. */
+	g_module_make_resident (module);
+
+	plugin_type = query_type_function ();
+	g_assert (g_type_is_a (plugin_type, GS_TYPE_PLUGIN));
+
+	plugin = g_object_new (plugin_type,
+			       "session-bus-connection", session_bus_connection,
+			       "system-bus-connection", system_bus_connection,
+			       NULL);
+	priv = gs_plugin_get_instance_private (plugin);
+	priv->module = g_steal_pointer (&module);
+
+	gs_plugin_set_name (plugin, basename + 13);
+	return plugin;
+}
+
+static void
+gs_plugin_dispose (GObject *object)
+{
+	GsPlugin *plugin = GS_PLUGIN (object);
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+
+	g_clear_object (&priv->session_bus_connection);
+	g_clear_object (&priv->system_bus_connection);
+
+	G_OBJECT_CLASS (gs_plugin_parent_class)->dispose (object);
+}
+
+static void
+gs_plugin_finalize (GObject *object)
+{
+	GsPlugin *plugin = GS_PLUGIN (object);
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	guint i;
+
+	for (i = 0; i < GS_PLUGIN_RULE_LAST; i++)
+		g_ptr_array_unref (priv->rules[i]);
+
+	if (priv->timer_id > 0)
+		g_source_remove (priv->timer_id);
+	g_free (priv->name);
+	g_free (priv->appstream_id);
+	g_free (priv->language);
+	if (priv->network_monitor != NULL)
+		g_object_unref (priv->network_monitor);
+	g_hash_table_unref (priv->cache);
+	g_hash_table_unref (priv->vfuncs);
+	g_mutex_clear (&priv->cache_mutex);
+	g_mutex_clear (&priv->interactive_mutex);
+	g_mutex_clear (&priv->timer_mutex);
+	g_mutex_clear (&priv->vfuncs_mutex);
+	if (priv->module != NULL)
+		g_module_close (priv->module);
+
+	G_OBJECT_CLASS (gs_plugin_parent_class)->finalize (object);
+}
+
+/**
+ * gs_plugin_get_symbol: (skip)
+ * @plugin: a #GsPlugin
+ * @function_name: a symbol name
+ *
+ * Gets the symbol from the module that backs the plugin. If the plugin is not
+ * enabled then no symbol is returned.
+ *
+ * Returns: the pointer to the symbol, or %NULL
+ *
+ * Since: 3.22
+ **/
+gpointer
+gs_plugin_get_symbol (GsPlugin *plugin, const gchar *function_name)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	gpointer func = NULL;
+	g_autoptr(GMutexLocker) locker = g_mutex_locker_new (&priv->vfuncs_mutex);
+
+	g_return_val_if_fail (function_name != NULL, NULL);
+
+	/* disabled plugins shouldn't be checked */
+	if (!priv->enabled)
+		return NULL;
+
+	/* look up the symbol from the cache */
+	if (g_hash_table_lookup_extended (priv->vfuncs, function_name, NULL, &func))
+		return func;
+
+	/* look up the symbol using the elf headers */
+	g_module_symbol (priv->module, function_name, &func);
+	g_hash_table_insert (priv->vfuncs, g_strdup (function_name), func);
+
+	return func;
+}
+
+/**
+ * gs_plugin_get_enabled:
+ * @plugin: a #GsPlugin
+ *
+ * Gets if the plugin is enabled.
+ *
+ * Returns: %TRUE if enabled
+ *
+ * Since: 3.22
+ **/
+gboolean
+gs_plugin_get_enabled (GsPlugin *plugin)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	return priv->enabled;
+}
+
+/**
+ * gs_plugin_set_enabled:
+ * @plugin: a #GsPlugin
+ * @enabled: the enabled state
+ *
+ * Enables or disables a plugin.
+ * This is normally only called from the init function for a #GsPlugin instance.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_set_enabled (GsPlugin *plugin, gboolean enabled)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	priv->enabled = enabled;
+}
+
+void
+gs_plugin_interactive_inc (GsPlugin *plugin)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	g_autoptr(GMutexLocker) locker = g_mutex_locker_new (&priv->interactive_mutex);
+	priv->interactive_cnt++;
+	gs_plugin_add_flags (plugin, GS_PLUGIN_FLAGS_INTERACTIVE);
+}
+
+void
+gs_plugin_interactive_dec (GsPlugin *plugin)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	g_autoptr(GMutexLocker) locker = g_mutex_locker_new (&priv->interactive_mutex);
+	if (priv->interactive_cnt > 0)
+		priv->interactive_cnt--;
+	if (priv->interactive_cnt == 0)
+		gs_plugin_remove_flags (plugin, GS_PLUGIN_FLAGS_INTERACTIVE);
+}
+
+/**
+ * gs_plugin_get_name:
+ * @plugin: a #GsPlugin
+ *
+ * Gets the plugin name.
+ *
+ * Returns: a string, e.g. "fwupd"
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_plugin_get_name (GsPlugin *plugin)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	return priv->name;
+}
+
+/**
+ * gs_plugin_get_appstream_id:
+ * @plugin: a #GsPlugin
+ *
+ * Gets the plugin AppStream ID.
+ *
+ * Returns: a string, e.g. `org.gnome.Software.Plugin.Epiphany`
+ *
+ * Since: 3.24
+ **/
+const gchar *
+gs_plugin_get_appstream_id (GsPlugin *plugin)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	return priv->appstream_id;
+}
+
+/**
+ * gs_plugin_set_appstream_id:
+ * @plugin: a #GsPlugin
+ * @appstream_id: an appstream ID, e.g. `org.gnome.Software.Plugin.Epiphany`
+ *
+ * Sets the plugin AppStream ID.
+ *
+ * Since: 3.24
+ **/
+void
+gs_plugin_set_appstream_id (GsPlugin *plugin, const gchar *appstream_id)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	g_free (priv->appstream_id);
+	priv->appstream_id = g_strdup (appstream_id);
+}
+
+/**
+ * gs_plugin_get_scale:
+ * @plugin: a #GsPlugin
+ *
+ * Gets the window scale factor.
+ *
+ * Returns: the factor, usually 1 for standard screens or 2 for HiDPI
+ *
+ * Since: 3.22
+ **/
+guint
+gs_plugin_get_scale (GsPlugin *plugin)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	return priv->scale;
+}
+
+/**
+ * gs_plugin_set_scale:
+ * @plugin: a #GsPlugin
+ * @scale: the window scale factor, usually 1 for standard screens or 2 for HiDPI
+ *
+ * Sets the window scale factor.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_set_scale (GsPlugin *plugin, guint scale)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	priv->scale = scale;
+}
+
+/**
+ * gs_plugin_get_order:
+ * @plugin: a #GsPlugin
+ *
+ * Gets the plugin order, where higher numbers are run after lower
+ * numbers.
+ *
+ * Returns: the integer value
+ *
+ * Since: 3.22
+ **/
+guint
+gs_plugin_get_order (GsPlugin *plugin)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	return priv->order;
+}
+
+/**
+ * gs_plugin_set_order:
+ * @plugin: a #GsPlugin
+ * @order: a integer value
+ *
+ * Sets the plugin order, where higher numbers are run after lower
+ * numbers.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_set_order (GsPlugin *plugin, guint order)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	priv->order = order;
+}
+
+/**
+ * gs_plugin_get_priority:
+ * @plugin: a #GsPlugin
+ *
+ * Gets the plugin priority, where higher values will be chosen where
+ * multiple #GsApp's match a specific rule.
+ *
+ * Returns: the integer value
+ *
+ * Since: 3.22
+ **/
+guint
+gs_plugin_get_priority (GsPlugin *plugin)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	return priv->priority;
+}
+
+/**
+ * gs_plugin_set_priority:
+ * @plugin: a #GsPlugin
+ * @priority: a integer value
+ *
+ * Sets the plugin priority, where higher values will be chosen where
+ * multiple #GsApp's match a specific rule.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_set_priority (GsPlugin *plugin, guint priority)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	priv->priority = priority;
+}
+
+/**
+ * gs_plugin_get_language:
+ * @plugin: a #GsPlugin
+ *
+ * Gets the user language from the locale. This is the first component of the
+ * locale.
+ *
+ * Typically you should use the full locale rather than the language, as the
+ * same language can be used quite differently in different territories.
+ *
+ * Returns: the language string, e.g. `fr`
+ *
+ * Since: 3.22
+ **/
+const gchar *
+gs_plugin_get_language (GsPlugin *plugin)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	return priv->language;
+}
+
+/**
+ * gs_plugin_set_language:
+ * @plugin: a #GsPlugin
+ * @language: a language string, e.g. "fr"
+ *
+ * Sets the plugin language.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_set_language (GsPlugin *plugin, const gchar *language)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	g_free (priv->language);
+	priv->language = g_strdup (language);
+}
+
+/**
+ * gs_plugin_set_network_monitor:
+ * @plugin: a #GsPlugin
+ * @monitor: a #GNetworkMonitor
+ *
+ * Sets the network monitor so that plugins can check the state of the network.
+ *
+ * Since: 3.28
+ **/
+void
+gs_plugin_set_network_monitor (GsPlugin *plugin, GNetworkMonitor *monitor)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	g_set_object (&priv->network_monitor, monitor);
+}
+
+/**
+ * gs_plugin_get_network_available:
+ * @plugin: a #GsPlugin
+ *
+ * Gets whether a network connectivity is available.
+ *
+ * Returns: %TRUE if a network is available.
+ *
+ * Since: 3.28
+ **/
+gboolean
+gs_plugin_get_network_available (GsPlugin *plugin)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	if (priv->network_monitor == NULL) {
+		g_debug ("no network monitor, so returning network-available=TRUE");
+		return TRUE;
+	}
+	return g_network_monitor_get_network_available (priv->network_monitor);
+}
+
+/**
+ * gs_plugin_has_flags:
+ * @plugin: a #GsPlugin
+ * @flags: a #GsPluginFlags, e.g. %GS_PLUGIN_FLAGS_INTERACTIVE
+ *
+ * Finds out if a plugin has a specific flag set.
+ *
+ * Returns: TRUE if the flag is set
+ *
+ * Since: 3.22
+ **/
+gboolean
+gs_plugin_has_flags (GsPlugin *plugin, GsPluginFlags flags)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	return (priv->flags & flags) > 0;
+}
+
+/**
+ * gs_plugin_add_flags:
+ * @plugin: a #GsPlugin
+ * @flags: a #GsPluginFlags, e.g. %GS_PLUGIN_FLAGS_INTERACTIVE
+ *
+ * Adds specific flags to the plugin.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_add_flags (GsPlugin *plugin, GsPluginFlags flags)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	priv->flags |= flags;
+	g_object_notify_by_pspec (G_OBJECT (plugin), obj_props[PROP_FLAGS]);
+}
+
+/**
+ * gs_plugin_remove_flags:
+ * @plugin: a #GsPlugin
+ * @flags: a #GsPluginFlags, e.g. %GS_PLUGIN_FLAGS_INTERACTIVE
+ *
+ * Removes specific flags from the plugin.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_remove_flags (GsPlugin *plugin, GsPluginFlags flags)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	priv->flags &= ~flags;
+	g_object_notify_by_pspec (G_OBJECT (plugin), obj_props[PROP_FLAGS]);
+}
+
+/**
+ * gs_plugin_add_rule:
+ * @plugin: a #GsPlugin
+ * @rule: a #GsPluginRule, e.g. %GS_PLUGIN_RULE_CONFLICTS
+ * @name: a plugin name, e.g. "appstream"
+ *
+ * If the plugin name is found, the rule will be used to sort the plugin list,
+ * for example the plugin specified by @name will be ordered after this plugin
+ * when %GS_PLUGIN_RULE_RUN_AFTER is used.
+ *
+ * NOTE: The depsolver is iterative and may not solve overly-complicated rules;
+ * If depsolving fails then gnome-software will not start.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_add_rule (GsPlugin *plugin, GsPluginRule rule, const gchar *name)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	g_ptr_array_add (priv->rules[rule], g_strdup (name));
+}
+
+/**
+ * gs_plugin_get_rules:
+ * @plugin: a #GsPlugin
+ * @rule: a #GsPluginRule, e.g. %GS_PLUGIN_RULE_CONFLICTS
+ *
+ * Gets the plugin IDs that should be run after this plugin.
+ *
+ * Returns: (element-type utf8) (transfer none): the list of plugin names, e.g. ['appstream']
+ *
+ * Since: 3.22
+ **/
+GPtrArray *
+gs_plugin_get_rules (GsPlugin *plugin, GsPluginRule rule)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	return priv->rules[rule];
+}
+
+/**
+ * gs_plugin_check_distro_id:
+ * @plugin: a #GsPlugin
+ * @distro_id: a distro ID, e.g. "fedora"
+ *
+ * Checks if the distro is compatible.
+ *
+ * Returns: %TRUE if compatible
+ *
+ * Since: 3.22
+ **/
+gboolean
+gs_plugin_check_distro_id (GsPlugin *plugin, const gchar *distro_id)
+{
+	g_autoptr(GError) error = NULL;
+	g_autoptr(GsOsRelease) os_release = NULL;
+	const gchar *id = NULL;
+
+	/* load /etc/os-release */
+	os_release = gs_os_release_new (&error);
+	if (os_release == NULL) {
+		g_debug ("could not parse os-release: %s", error->message);
+		return FALSE;
+	}
+
+	/* check that we are running on Fedora */
+	id = gs_os_release_get_id (os_release);
+	if (id == NULL) {
+		g_debug ("could not get distro ID");
+		return FALSE;
+	}
+	if (g_strcmp0 (id, distro_id) != 0)
+		return FALSE;
+	return TRUE;
+}
+
+typedef struct {
+	GWeakRef	 plugin_weak;  /* (element-type GsPlugin) */
+	GsApp		*app;  /* (owned) */
+	GsPluginStatus	 status;
+	guint		 percentage;
+} GsPluginStatusHelper;
+
+static void
+gs_plugin_status_helper_free (GsPluginStatusHelper *helper)
+{
+	g_weak_ref_clear (&helper->plugin_weak);
+	g_clear_object (&helper->app);
+	g_slice_free (GsPluginStatusHelper, helper);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (GsPluginStatusHelper, gs_plugin_status_helper_free)
+
+static gboolean
+gs_plugin_status_update_cb (gpointer user_data)
+{
+	GsPluginStatusHelper *helper = (GsPluginStatusHelper *) user_data;
+	g_autoptr(GsPlugin) plugin = NULL;
+
+	/* Does the plugin still exist? */
+	plugin = g_weak_ref_get (&helper->plugin_weak);
+
+	if (plugin != NULL)
+		g_signal_emit (plugin,
+			       signals[SIGNAL_STATUS_CHANGED], 0,
+			       helper->app,
+			       helper->status);
+
+	return G_SOURCE_REMOVE;
+}
+
+/**
+ * gs_plugin_status_update:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp, or %NULL
+ * @status: a #GsPluginStatus, e.g. %GS_PLUGIN_STATUS_DOWNLOADING
+ *
+ * Update the state of the plugin so any UI can be updated.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_status_update (GsPlugin *plugin, GsApp *app, GsPluginStatus status)
+{
+	g_autoptr(GsPluginStatusHelper) helper = NULL;
+	g_autoptr(GSource) idle_source = NULL;
+
+	helper = g_slice_new0 (GsPluginStatusHelper);
+	g_weak_ref_init (&helper->plugin_weak, plugin);
+	helper->status = status;
+	if (app != NULL)
+		helper->app = g_object_ref (app);
+
+	idle_source = g_idle_source_new ();
+	g_source_set_callback (idle_source, gs_plugin_status_update_cb, g_steal_pointer (&helper), (GDestroyNotify) gs_plugin_status_helper_free);
+	g_source_attach (idle_source, NULL);
+}
+
+typedef struct {
+	GsPlugin	*plugin;
+	gchar		*remote;
+	gchar		*realm;
+	GCallback	 callback;
+	gpointer	 user_data;
+} GsPluginBasicAuthHelper;
+
+static gboolean
+gs_plugin_basic_auth_start_cb (gpointer user_data)
+{
+	GsPluginBasicAuthHelper *helper = user_data;
+	g_signal_emit (helper->plugin,
+		       signals[SIGNAL_BASIC_AUTH_START], 0,
+		       helper->remote,
+		       helper->realm,
+		       helper->callback,
+		       helper->user_data);
+	g_free (helper->remote);
+	g_free (helper->realm);
+	g_slice_free (GsPluginBasicAuthHelper, helper);
+	return FALSE;
+}
+
+/**
+ * gs_plugin_basic_auth_start:
+ * @plugin: a #GsPlugin
+ * @remote: a string
+ * @realm: a string
+ * @callback: callback to invoke to submit the user/password
+ * @user_data: callback data to pass to the callback
+ *
+ * Emit the basic-auth-start signal in the main thread.
+ *
+ * Since: 3.38
+ **/
+void
+gs_plugin_basic_auth_start (GsPlugin *plugin,
+                            const gchar *remote,
+                            const gchar *realm,
+                            GCallback callback,
+                            gpointer user_data)
+{
+	GsPluginBasicAuthHelper *helper;
+	g_autoptr(GSource) idle_source = NULL;
+
+	helper = g_slice_new0 (GsPluginBasicAuthHelper);
+	helper->plugin = plugin;
+	helper->remote = g_strdup (remote);
+	helper->realm = g_strdup (realm);
+	helper->callback = callback;
+	helper->user_data = user_data;
+
+	idle_source = g_idle_source_new ();
+	g_source_set_callback (idle_source, gs_plugin_basic_auth_start_cb, helper, NULL);
+	g_source_attach (idle_source, NULL);
+}
+
+static gboolean
+gs_plugin_app_launch_cb (gpointer user_data)
+{
+	GAppInfo *appinfo = (GAppInfo *) user_data;
+	GdkDisplay *display;
+	g_autoptr(GAppLaunchContext) context = NULL;
+	g_autoptr(GError) error = NULL;
+
+	display = gdk_display_get_default ();
+	context = G_APP_LAUNCH_CONTEXT (gdk_display_get_app_launch_context (display));
+	if (!g_app_info_launch (appinfo, NULL, context, &error))
+		g_warning ("Failed to launch: %s", error->message);
+
+	return G_SOURCE_REMOVE;
+}
+
+/**
+ * gs_plugin_app_launch:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp
+ * @error: a #GError, or %NULL
+ *
+ * Launches the application using #GAppInfo.
+ *
+ * Returns: %TRUE for success
+ *
+ * Since: 3.22
+ **/
+gboolean
+gs_plugin_app_launch (GsPlugin *plugin, GsApp *app, GError **error)
+{
+	const gchar *desktop_id;
+	g_autoptr(GAppInfo) appinfo = NULL;
+
+	desktop_id = gs_app_get_launchable (app, AS_LAUNCHABLE_KIND_DESKTOP_ID);
+	if (desktop_id == NULL)
+		desktop_id = gs_app_get_id (app);
+	if (desktop_id == NULL) {
+		g_set_error (error,
+			     GS_PLUGIN_ERROR,
+			     GS_PLUGIN_ERROR_NOT_SUPPORTED,
+			     "no such desktop file: %s",
+			     desktop_id);
+		return FALSE;
+	}
+	appinfo = G_APP_INFO (gs_utils_get_desktop_app_info (desktop_id));
+	if (appinfo == NULL) {
+		g_set_error (error,
+			     GS_PLUGIN_ERROR,
+			     GS_PLUGIN_ERROR_NOT_SUPPORTED,
+			     "no such desktop file: %s",
+			     desktop_id);
+		return FALSE;
+	}
+	g_idle_add_full (G_PRIORITY_DEFAULT,
+			 gs_plugin_app_launch_cb,
+			 g_object_ref (appinfo),
+			 (GDestroyNotify) g_object_unref);
+	return TRUE;
+}
+
+static GDesktopAppInfo *
+check_directory_for_desktop_file (GsPlugin *plugin,
+				  GsApp *app,
+				  GsPluginPickDesktopFileCallback cb,
+				  gpointer user_data,
+				  const gchar *desktop_id,
+				  const gchar *data_dir)
+{
+	g_autofree gchar *filename = NULL;
+	g_autoptr(GKeyFile) key_file = NULL;
+
+	filename = g_build_filename (data_dir, "applications", desktop_id, NULL);
+	key_file = g_key_file_new ();
+
+	if (g_key_file_load_from_file (key_file, filename, G_KEY_FILE_KEEP_TRANSLATIONS, NULL) &&
+	    cb (plugin, app, filename, key_file)) {
+		g_autoptr(GDesktopAppInfo) appinfo = NULL;
+		appinfo = g_desktop_app_info_new_from_keyfile (key_file);
+		if (appinfo != NULL)
+			return g_steal_pointer (&appinfo);
+		g_debug ("Failed to load '%s' as a GDesktopAppInfo", filename);
+		return NULL;
+	}
+
+	if (!g_str_has_suffix (desktop_id, ".desktop")) {
+		g_autofree gchar *desktop_filename = g_strconcat (filename, ".desktop", NULL);
+		if (g_key_file_load_from_file (key_file, desktop_filename, G_KEY_FILE_KEEP_TRANSLATIONS, NULL) &&
+		    cb (plugin, app, desktop_filename, key_file)) {
+			g_autoptr(GDesktopAppInfo) appinfo = NULL;
+			appinfo = g_desktop_app_info_new_from_keyfile (key_file);
+			if (appinfo != NULL)
+				return g_steal_pointer (&appinfo);
+			g_debug ("Failed to load '%s' as a GDesktopAppInfo", desktop_filename);
+			return NULL;
+		}
+	}
+
+	return NULL;
+}
+
+/**
+ * gs_plugin_app_launch_filtered:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp to launch
+ * @cb: a callback to pick the correct .desktop file
+ * @user_data: (closure cb) (scope call): user data for the @cb
+ * @error: a #GError, or %NULL
+ *
+ * Launches application @app, using the .desktop file picked by the @cb.
+ * This can help in case multiple versions of the @app are installed
+ * in the system (like a Flatpak and RPM versions).
+ *
+ * Returns: %TRUE on success
+ *
+ * Since: 43
+ **/
+gboolean
+gs_plugin_app_launch_filtered (GsPlugin *plugin,
+			       GsApp *app,
+			       GsPluginPickDesktopFileCallback cb,
+			       gpointer user_data,
+			       GError **error)
+{
+	const gchar *desktop_id;
+	g_autoptr(GDesktopAppInfo) appinfo = NULL;
+
+	g_return_val_if_fail (GS_IS_PLUGIN (plugin), FALSE);
+	g_return_val_if_fail (GS_IS_APP (app), FALSE);
+	g_return_val_if_fail (cb != NULL, FALSE);
+
+	desktop_id = gs_app_get_launchable (app, AS_LAUNCHABLE_KIND_DESKTOP_ID);
+	if (desktop_id == NULL)
+		desktop_id = gs_app_get_id (app);
+	if (desktop_id == NULL) {
+		g_set_error (error,
+			     GS_PLUGIN_ERROR,
+			     GS_PLUGIN_ERROR_NOT_SUPPORTED,
+			     "no desktop file for app: %s",
+			     gs_app_get_name (app));
+		return FALSE;
+	}
+
+	/* First, the configs.  Highest priority: the user's ~/.config */
+	appinfo = check_directory_for_desktop_file (plugin, app, cb, user_data, desktop_id, g_get_user_config_dir ());
+
+	if (appinfo == NULL) {
+		/* Next, the system configs (/etc/xdg, and so on). */
+		const gchar * const *dirs;
+		dirs = g_get_system_config_dirs ();
+		for (guint i = 0; dirs[i] && appinfo == NULL; i++) {
+			appinfo = check_directory_for_desktop_file (plugin, app, cb, user_data, desktop_id, dirs[i]);
+		}
+	}
+
+	if (appinfo == NULL) {
+		/* Now the data.  Highest priority: the user's ~/.local/share/applications */
+		appinfo = check_directory_for_desktop_file (plugin, app, cb, user_data, desktop_id, g_get_user_data_dir ());
+	}
+
+	if (appinfo == NULL) {
+		/* Following that, XDG_DATA_DIRS/applications, in order */
+		const gchar * const *dirs;
+		dirs = g_get_system_data_dirs ();
+		for (guint i = 0; dirs[i] && appinfo == NULL; i++) {
+			appinfo = check_directory_for_desktop_file (plugin, app, cb, user_data, desktop_id, dirs[i]);
+		}
+	}
+
+	if (appinfo == NULL) {
+		g_set_error (error,
+			     GS_PLUGIN_ERROR,
+			     GS_PLUGIN_ERROR_NOT_SUPPORTED,
+			     "no appropriate desktop file found: %s",
+			     desktop_id);
+		return FALSE;
+	}
+
+	g_idle_add_full (G_PRIORITY_DEFAULT,
+			 gs_plugin_app_launch_cb,
+			 g_object_ref (appinfo),
+			 (GDestroyNotify) g_object_unref);
+
+	return TRUE;
+}
+
+static void
+weak_ref_free (GWeakRef *weak)
+{
+	g_weak_ref_clear (weak);
+	g_free (weak);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (GWeakRef, weak_ref_free)
+
+/* @obj is a gpointer rather than a GObject* to avoid the need for casts */
+static GWeakRef *
+weak_ref_new (gpointer obj)
+{
+	g_autoptr(GWeakRef) weak = g_new0 (GWeakRef, 1);
+	g_weak_ref_init (weak, obj);
+	return g_steal_pointer (&weak);
+}
+
+static gboolean
+gs_plugin_updates_changed_cb (gpointer user_data)
+{
+	GWeakRef *plugin_weak = user_data;
+	g_autoptr(GsPlugin) plugin = NULL;
+
+	plugin = g_weak_ref_get (plugin_weak);
+	if (plugin != NULL)
+		g_signal_emit (plugin, signals[SIGNAL_UPDATES_CHANGED], 0);
+
+	return G_SOURCE_REMOVE;
+}
+
+/**
+ * gs_plugin_updates_changed:
+ * @plugin: a #GsPlugin
+ *
+ * Emit a signal that tells the plugin loader that the list of updates
+ * may have changed.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_updates_changed (GsPlugin *plugin)
+{
+	g_idle_add_full (G_PRIORITY_DEFAULT_IDLE, gs_plugin_updates_changed_cb,
+			 weak_ref_new (plugin), (GDestroyNotify) weak_ref_free);
+}
+
+static gboolean
+gs_plugin_reload_cb (gpointer user_data)
+{
+	GWeakRef *plugin_weak = user_data;
+	g_autoptr(GsPlugin) plugin = NULL;
+
+	plugin = g_weak_ref_get (plugin_weak);
+	if (plugin != NULL)
+		g_signal_emit (plugin, signals[SIGNAL_RELOAD], 0);
+
+	return G_SOURCE_REMOVE;
+}
+
+/**
+ * gs_plugin_reload:
+ * @plugin: a #GsPlugin
+ *
+ * Plugins that call this function should expect that all panels will
+ * reload after a small delay, causing mush flashing, wailing and
+ * gnashing of teeth.
+ *
+ * Plugins should not call this unless absolutely required.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_reload (GsPlugin *plugin)
+{
+	g_debug ("emitting %s::reload in idle", gs_plugin_get_name (plugin));
+	g_idle_add_full (G_PRIORITY_DEFAULT_IDLE, gs_plugin_reload_cb,
+			 weak_ref_new (plugin), (GDestroyNotify) weak_ref_free);
+}
+
+typedef struct {
+	GsPlugin	*plugin;
+	GsApp		*app;
+} GsPluginDownloadHelper;
+
+static void
+download_file_progress_cb (gsize    total_written_bytes,
+                           gsize    total_download_size,
+                           gpointer user_data)
+{
+	GsPluginDownloadHelper *helper = user_data;
+	guint percentage;
+
+	if (total_download_size > 0)
+		percentage = (guint) ((100 * total_written_bytes) / total_download_size);
+	else
+		percentage = 0;
+
+	g_debug ("%s progress: %u%%", gs_app_get_id (helper->app), percentage);
+	gs_app_set_progress (helper->app, percentage);
+	gs_plugin_status_update (helper->plugin,
+				 helper->app,
+				 GS_PLUGIN_STATUS_DOWNLOADING);
+
+}
+
+static void
+async_result_cb (GObject      *source_object,
+                 GAsyncResult *result,
+                 gpointer      user_data)
+{
+	GAsyncResult **result_out = user_data;
+
+	g_assert (*result_out == NULL);
+	*result_out = g_object_ref (result);
+	g_main_context_wakeup (g_main_context_get_thread_default ());
+}
+
+/**
+ * gs_plugin_download_file:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp, or %NULL
+ * @uri: a remote URI
+ * @filename: a local filename
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Downloads data and saves it to a file.
+ *
+ * Returns: %TRUE for success
+ *
+ * Since: 3.22
+ **/
+gboolean
+gs_plugin_download_file (GsPlugin *plugin,
+			 GsApp *app,
+			 const gchar *uri,
+			 const gchar *filename,
+			 GCancellable *cancellable,
+			 GError **error)
+{
+	g_autoptr(SoupSession) soup_session = NULL;
+	g_autoptr(GFile) output_file = NULL;
+	g_autoptr(GAsyncResult) result = NULL;
+	g_autoptr(GMainContext) context = g_main_context_new ();
+	g_autoptr(GMainContextPusher) context_pusher = g_main_context_pusher_new (context);
+	GsPluginDownloadHelper helper;
+	g_autoptr(GError) local_error = NULL;
+
+	helper.plugin = plugin;
+	helper.app = app;
+
+	soup_session = gs_build_soup_session ();
+
+	/* Do the download. */
+	output_file = g_file_new_for_path (filename);
+	gs_download_file_async (soup_session, uri, output_file,
+				G_PRIORITY_LOW,
+				download_file_progress_cb, &helper,
+				cancellable, async_result_cb, &result);
+
+	while (result == NULL)
+		g_main_context_iteration (context, TRUE);
+
+	if (!gs_download_file_finish (soup_session, result, &local_error) &&
+	    !g_error_matches (local_error, GS_DOWNLOAD_ERROR, GS_DOWNLOAD_ERROR_NOT_MODIFIED)) {
+		g_set_error_literal (error,
+				     GS_PLUGIN_ERROR,
+				     GS_PLUGIN_ERROR_DOWNLOAD_FAILED,
+				     local_error->message);
+		return FALSE;
+	}
+
+	return TRUE;
+}
+
+static gchar *
+gs_plugin_download_rewrite_resource_uri (GsPlugin *plugin,
+					 GsApp *app,
+					 const gchar *uri,
+					 GCancellable *cancellable,
+					 GError **error)
+{
+	g_autofree gchar *cachefn = NULL;
+
+	/* local files */
+	if (g_str_has_prefix (uri, "file://"))
+		uri += 7;
+	if (g_str_has_prefix (uri, "/")) {
+		if (!g_file_test (uri, G_FILE_TEST_EXISTS)) {
+			g_set_error (error,
+				     GS_PLUGIN_ERROR,
+				     GS_PLUGIN_ERROR_NOT_SUPPORTED,
+				     "Failed to find file: %s", uri);
+			return NULL;
+		}
+		return g_strdup (uri);
+	}
+
+	/* get cache location */
+	cachefn = gs_utils_get_cache_filename ("cssresource", uri,
+					       GS_UTILS_CACHE_FLAG_WRITEABLE |
+					       GS_UTILS_CACHE_FLAG_USE_HASH |
+					       GS_UTILS_CACHE_FLAG_CREATE_DIRECTORY,
+					       error);
+	if (cachefn == NULL)
+		return NULL;
+
+	/* already exists */
+	if (g_file_test (cachefn, G_FILE_TEST_EXISTS))
+		return g_steal_pointer (&cachefn);
+
+	/* download */
+	if (!gs_plugin_download_file (plugin, app, uri, cachefn,
+				      cancellable, error)) {
+		return NULL;
+	}
+	return g_steal_pointer (&cachefn);
+}
+
+/**
+ * gs_plugin_download_rewrite_resource:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp, or %NULL
+ * @resource: the CSS resource
+ * @cancellable: a #GCancellable, or %NULL
+ * @error: a #GError, or %NULL
+ *
+ * Downloads remote assets and rewrites a CSS resource to use cached local URIs.
+ *
+ * Returns: %TRUE for success
+ *
+ * Since: 3.26
+ **/
+gchar *
+gs_plugin_download_rewrite_resource (GsPlugin *plugin,
+				     GsApp *app,
+				     const gchar *resource,
+				     GCancellable *cancellable,
+				     GError **error)
+{
+	guint start = 0;
+	g_autoptr(GString) resource_str = g_string_new (resource);
+	g_autoptr(GString) str = g_string_new (NULL);
+
+	g_return_val_if_fail (GS_IS_PLUGIN (plugin), NULL);
+	g_return_val_if_fail (resource != NULL, NULL);
+	g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+
+	/* replace datadir */
+	as_gstring_replace (resource_str, "@datadir@", DATADIR);
+	resource = resource_str->str;
+
+	/* look in string for any url() links */
+	for (guint i = 0; resource[i] != '\0'; i++) {
+		if (i > 4 && strncmp (resource + i - 4, "url(", 4) == 0) {
+			start = i;
+			continue;
+		}
+		if (start == 0) {
+			g_string_append_c (str, resource[i]);
+			continue;
+		}
+		if (resource[i] == ')') {
+			guint len;
+			g_autofree gchar *cachefn = NULL;
+			g_autofree gchar *uri = NULL;
+
+			/* remove optional single quotes */
+			if (resource[start] == '\'' || resource[start] == '"')
+				start++;
+			len = i - start;
+			if (i > 0 && (resource[i - 1] == '\'' || resource[i - 1] == '"'))
+				len--;
+			uri = g_strndup (resource + start, len);
+
+			/* download them to per-user cache */
+			cachefn = gs_plugin_download_rewrite_resource_uri (plugin,
+									   app,
+									   uri,
+									   cancellable,
+									   error);
+			if (cachefn == NULL)
+				return NULL;
+			g_string_append_printf (str, "'file://%s'", cachefn);
+			g_string_append_c (str, resource[i]);
+			start = 0;
+		}
+	}
+	return g_strdup (str->str);
+}
+
+/**
+ * gs_plugin_cache_lookup:
+ * @plugin: a #GsPlugin
+ * @key: a string
+ *
+ * Looks up an application object from the per-plugin cache
+ *
+ * Returns: (transfer full) (nullable): the #GsApp, or %NULL
+ *
+ * Since: 3.22
+ **/
+GsApp *
+gs_plugin_cache_lookup (GsPlugin *plugin, const gchar *key)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	GsApp *app;
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_val_if_fail (GS_IS_PLUGIN (plugin), NULL);
+	g_return_val_if_fail (key != NULL, NULL);
+
+	locker = g_mutex_locker_new (&priv->cache_mutex);
+	app = g_hash_table_lookup (priv->cache, key);
+	if (app == NULL)
+		return NULL;
+	return g_object_ref (app);
+}
+
+/**
+ * gs_plugin_cache_lookup_by_state:
+ * @plugin: a #GsPlugin
+ * @list: a #GsAppList to add applications to
+ * @state: a #GsAppState
+ *
+ * Adds each cached #GsApp with state @state into the @list.
+ * When the state is %GS_APP_STATE_UNKNOWN, then adds all
+ * cached applications.
+ *
+ * Since: 40
+ **/
+void
+gs_plugin_cache_lookup_by_state (GsPlugin *plugin,
+				 GsAppList *list,
+				 GsAppState state)
+{
+	GsPluginPrivate *priv;
+	GHashTableIter iter;
+	gpointer value;
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_PLUGIN (plugin));
+	g_return_if_fail (GS_IS_APP_LIST (list));
+
+	priv = gs_plugin_get_instance_private (plugin);
+	locker = g_mutex_locker_new (&priv->cache_mutex);
+
+	g_hash_table_iter_init (&iter, priv->cache);
+	while (g_hash_table_iter_next (&iter, NULL, &value)) {
+		GsApp *app = value;
+
+		if (state == GS_APP_STATE_UNKNOWN ||
+		    state == gs_app_get_state (app))
+			gs_app_list_add (list, app);
+	}
+}
+
+/**
+ * gs_plugin_cache_remove:
+ * @plugin: a #GsPlugin
+ * @key: a key which matches
+ *
+ * Removes an application from the per-plugin cache.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_cache_remove (GsPlugin *plugin, const gchar *key)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_PLUGIN (plugin));
+	g_return_if_fail (key != NULL);
+
+	locker = g_mutex_locker_new (&priv->cache_mutex);
+	g_hash_table_remove (priv->cache, key);
+}
+
+/**
+ * gs_plugin_cache_add:
+ * @plugin: a #GsPlugin
+ * @key: a string, or %NULL if the unique ID should be used
+ * @app: a #GsApp
+ *
+ * Adds an application to the per-plugin cache. This is optional,
+ * and the plugin can use the cache however it likes.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_cache_add (GsPlugin *plugin, const gchar *key, GsApp *app)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_PLUGIN (plugin));
+	g_return_if_fail (GS_IS_APP (app));
+
+	locker = g_mutex_locker_new (&priv->cache_mutex);
+
+	/* the user probably doesn't want to do this */
+	if (gs_app_has_quirk (app, GS_APP_QUIRK_IS_WILDCARD)) {
+		g_warning ("adding wildcard app %s to plugin cache",
+			   gs_app_get_unique_id (app));
+	}
+
+	/* default */
+	if (key == NULL)
+		key = gs_app_get_unique_id (app);
+
+	g_return_if_fail (key != NULL);
+
+	if (g_hash_table_lookup (priv->cache, key) == app)
+		return;
+	g_hash_table_insert (priv->cache, g_strdup (key), g_object_ref (app));
+}
+
+/**
+ * gs_plugin_cache_invalidate:
+ * @plugin: a #GsPlugin
+ *
+ * Invalidate the per-plugin cache by marking all entries as invalid.
+ * This is optional, and the plugin can evict the cache whenever it
+ * likes. Using this function may mean the front-end and the plugin
+ * may be operating on a different GsApp with the same cache ID.
+ *
+ * Most plugins do not need to call this function; if a suitable cache
+ * key is being used the old cache item can remain.
+ *
+ * Since: 3.22
+ **/
+void
+gs_plugin_cache_invalidate (GsPlugin *plugin)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	g_autoptr(GMutexLocker) locker = NULL;
+
+	g_return_if_fail (GS_IS_PLUGIN (plugin));
+
+	locker = g_mutex_locker_new (&priv->cache_mutex);
+	g_hash_table_remove_all (priv->cache);
+}
+
+/**
+ * gs_plugin_report_event:
+ * @plugin: a #GsPlugin
+ * @event: a #GsPluginEvent
+ *
+ * Report a non-fatal event to the UI. Plugins should not assume that a
+ * specific event is actually shown to the user as it may be ignored
+ * automatically.
+ *
+ * Since: 3.24
+ **/
+void
+gs_plugin_report_event (GsPlugin *plugin, GsPluginEvent *event)
+{
+	g_return_if_fail (GS_IS_PLUGIN (plugin));
+	g_return_if_fail (GS_IS_PLUGIN_EVENT (event));
+	g_signal_emit (plugin, signals[SIGNAL_REPORT_EVENT], 0, event);
+}
+
+/**
+ * gs_plugin_set_allow_updates:
+ * @plugin: a #GsPlugin
+ * @allow_updates: boolean
+ *
+ * This allows plugins to inhibit the showing of the updates panel.
+ * This will typically be used when the required permissions are not possible
+ * to obtain, or when a LiveUSB image is low on space.
+ *
+ * By default, the updates panel is shown so plugins do not need to call this
+ * function unless they called gs_plugin_set_allow_updates() with %FALSE.
+ *
+ * Since: 3.24
+ **/
+void
+gs_plugin_set_allow_updates (GsPlugin *plugin, gboolean allow_updates)
+{
+	g_return_if_fail (GS_IS_PLUGIN (plugin));
+	g_signal_emit (plugin, signals[SIGNAL_ALLOW_UPDATES], 0, allow_updates);
+}
+
+/**
+ * gs_plugin_error_to_string:
+ * @error: a #GsPluginError, e.g. %GS_PLUGIN_ERROR_NO_NETWORK
+ *
+ * Converts the enumerated error to a string.
+ *
+ * Returns: a string, or %NULL for invalid
+ **/
+const gchar *
+gs_plugin_error_to_string (GsPluginError error)
+{
+	if (error == GS_PLUGIN_ERROR_FAILED)
+		return "failed";
+	if (error == GS_PLUGIN_ERROR_NOT_SUPPORTED)
+		return "not-supported";
+	if (error == GS_PLUGIN_ERROR_CANCELLED)
+		return "cancelled";
+	if (error == GS_PLUGIN_ERROR_NO_NETWORK)
+		return "no-network";
+	if (error == GS_PLUGIN_ERROR_NO_SECURITY)
+		return "no-security";
+	if (error == GS_PLUGIN_ERROR_NO_SPACE)
+		return "no-space";
+	if (error == GS_PLUGIN_ERROR_AUTH_REQUIRED)
+		return "auth-required";
+	if (error == GS_PLUGIN_ERROR_AUTH_INVALID)
+		return "auth-invalid";
+	if (error == GS_PLUGIN_ERROR_PLUGIN_DEPSOLVE_FAILED)
+		return "plugin-depsolve-failed";
+	if (error == GS_PLUGIN_ERROR_DOWNLOAD_FAILED)
+		return "download-failed";
+	if (error == GS_PLUGIN_ERROR_WRITE_FAILED)
+		return "write-failed";
+	if (error == GS_PLUGIN_ERROR_INVALID_FORMAT)
+		return "invalid-format";
+	if (error == GS_PLUGIN_ERROR_DELETE_FAILED)
+		return "delete-failed";
+	if (error == GS_PLUGIN_ERROR_RESTART_REQUIRED)
+		return "restart-required";
+	if (error == GS_PLUGIN_ERROR_AC_POWER_REQUIRED)
+		return "ac-power-required";
+	if (error == GS_PLUGIN_ERROR_BATTERY_LEVEL_TOO_LOW)
+		return "battery-level-too-low";
+	if (error == GS_PLUGIN_ERROR_TIMED_OUT)
+		return "timed-out";
+	return NULL;
+}
+
+/**
+ * gs_plugin_action_to_function_name: (skip)
+ * @action: a #GsPluginAction, e.g. %GS_PLUGIN_ACTION_INSTALL
+ *
+ * Converts the enumerated action to the vfunc name.
+ *
+ * Returns: a string, or %NULL for invalid
+ **/
+const gchar *
+gs_plugin_action_to_function_name (GsPluginAction action)
+{
+	if (action == GS_PLUGIN_ACTION_INSTALL)
+		return "gs_plugin_app_install";
+	if (action == GS_PLUGIN_ACTION_REMOVE)
+		return "gs_plugin_app_remove";
+	if (action == GS_PLUGIN_ACTION_UPGRADE_DOWNLOAD)
+		return "gs_plugin_app_upgrade_download";
+	if (action == GS_PLUGIN_ACTION_UPGRADE_TRIGGER)
+		return "gs_plugin_app_upgrade_trigger";
+	if (action == GS_PLUGIN_ACTION_LAUNCH)
+		return "gs_plugin_launch";
+	if (action == GS_PLUGIN_ACTION_UPDATE_CANCEL)
+		return "gs_plugin_update_cancel";
+	if (action == GS_PLUGIN_ACTION_UPDATE)
+		return "gs_plugin_update";
+	if (action == GS_PLUGIN_ACTION_DOWNLOAD)
+		return "gs_plugin_download";
+	if (action == GS_PLUGIN_ACTION_FILE_TO_APP)
+		return "gs_plugin_file_to_app";
+	if (action == GS_PLUGIN_ACTION_URL_TO_APP)
+		return "gs_plugin_url_to_app";
+	if (action == GS_PLUGIN_ACTION_GET_SOURCES)
+		return "gs_plugin_add_sources";
+	if (action == GS_PLUGIN_ACTION_GET_UPDATES_HISTORICAL)
+		return "gs_plugin_add_updates_historical";
+	if (action == GS_PLUGIN_ACTION_GET_UPDATES)
+		return "gs_plugin_add_updates";
+	if (action == GS_PLUGIN_ACTION_GET_LANGPACKS)
+		return "gs_plugin_add_langpacks";
+	return NULL;
+}
+
+/**
+ * gs_plugin_action_to_string:
+ * @action: a #GsPluginAction, e.g. %GS_PLUGIN_ACTION_INSTALL
+ *
+ * Converts the enumerated action to a string.
+ *
+ * Returns: a string, or %NULL for invalid
+ **/
+const gchar *
+gs_plugin_action_to_string (GsPluginAction action)
+{
+	if (action == GS_PLUGIN_ACTION_UNKNOWN)
+		return "unknown";
+	if (action == GS_PLUGIN_ACTION_INSTALL)
+		return "install";
+	if (action == GS_PLUGIN_ACTION_DOWNLOAD)
+		return "download";
+	if (action == GS_PLUGIN_ACTION_REMOVE)
+		return "remove";
+	if (action == GS_PLUGIN_ACTION_UPDATE)
+		return "update";
+	if (action == GS_PLUGIN_ACTION_UPGRADE_DOWNLOAD)
+		return "upgrade-download";
+	if (action == GS_PLUGIN_ACTION_UPGRADE_TRIGGER)
+		return "upgrade-trigger";
+	if (action == GS_PLUGIN_ACTION_LAUNCH)
+		return "launch";
+	if (action == GS_PLUGIN_ACTION_UPDATE_CANCEL)
+		return "update-cancel";
+	if (action == GS_PLUGIN_ACTION_GET_UPDATES)
+		return "get-updates";
+	if (action == GS_PLUGIN_ACTION_GET_SOURCES)
+		return "get-sources";
+	if (action == GS_PLUGIN_ACTION_FILE_TO_APP)
+		return "file-to-app";
+	if (action == GS_PLUGIN_ACTION_URL_TO_APP)
+		return "url-to-app";
+	if (action == GS_PLUGIN_ACTION_GET_UPDATES_HISTORICAL)
+		return "get-updates-historical";
+	if (action == GS_PLUGIN_ACTION_GET_LANGPACKS)
+		return "get-langpacks";
+	if (action == GS_PLUGIN_ACTION_INSTALL_REPO)
+		return "repo-install";
+	if (action == GS_PLUGIN_ACTION_REMOVE_REPO)
+		return "repo-remove";
+	if (action == GS_PLUGIN_ACTION_ENABLE_REPO)
+		return "repo-enable";
+	if (action == GS_PLUGIN_ACTION_DISABLE_REPO)
+		return "repo-disable";
+	return NULL;
+}
+
+/**
+ * gs_plugin_action_from_string:
+ * @action: a #GsPluginAction, e.g. "install"
+ *
+ * Converts the string to an enumerated action.
+ *
+ * Returns: a GsPluginAction, e.g. %GS_PLUGIN_ACTION_INSTALL
+ *
+ * Since: 3.26
+ **/
+GsPluginAction
+gs_plugin_action_from_string (const gchar *action)
+{
+	if (g_strcmp0 (action, "install") == 0)
+		return GS_PLUGIN_ACTION_INSTALL;
+	if (g_strcmp0 (action, "download") == 0)
+		return GS_PLUGIN_ACTION_DOWNLOAD;
+	if (g_strcmp0 (action, "remove") == 0)
+		return GS_PLUGIN_ACTION_REMOVE;
+	if (g_strcmp0 (action, "update") == 0)
+		return GS_PLUGIN_ACTION_UPDATE;
+	if (g_strcmp0 (action, "upgrade-download") == 0)
+		return GS_PLUGIN_ACTION_UPGRADE_DOWNLOAD;
+	if (g_strcmp0 (action, "upgrade-trigger") == 0)
+		return GS_PLUGIN_ACTION_UPGRADE_TRIGGER;
+	if (g_strcmp0 (action, "launch") == 0)
+		return GS_PLUGIN_ACTION_LAUNCH;
+	if (g_strcmp0 (action, "update-cancel") == 0)
+		return GS_PLUGIN_ACTION_UPDATE_CANCEL;
+	if (g_strcmp0 (action, "get-updates") == 0)
+		return GS_PLUGIN_ACTION_GET_UPDATES;
+	if (g_strcmp0 (action, "get-sources") == 0)
+		return GS_PLUGIN_ACTION_GET_SOURCES;
+	if (g_strcmp0 (action, "file-to-app") == 0)
+		return GS_PLUGIN_ACTION_FILE_TO_APP;
+	if (g_strcmp0 (action, "url-to-app") == 0)
+		return GS_PLUGIN_ACTION_URL_TO_APP;
+	if (g_strcmp0 (action, "get-updates-historical") == 0)
+		return GS_PLUGIN_ACTION_GET_UPDATES_HISTORICAL;
+	if (g_strcmp0 (action, "get-langpacks") == 0)
+		return GS_PLUGIN_ACTION_GET_LANGPACKS;
+	if (g_strcmp0 (action, "repo-install") == 0)
+		return GS_PLUGIN_ACTION_INSTALL_REPO;
+	if (g_strcmp0 (action, "repo-remove") == 0)
+		return GS_PLUGIN_ACTION_REMOVE_REPO;
+	if (g_strcmp0 (action, "repo-enable") == 0)
+		return GS_PLUGIN_ACTION_ENABLE_REPO;
+	if (g_strcmp0 (action, "repo-disable") == 0)
+		return GS_PLUGIN_ACTION_DISABLE_REPO;
+	return GS_PLUGIN_ACTION_UNKNOWN;
+}
+
+/**
+ * gs_plugin_refine_flags_to_string:
+ * @refine_flags: some #GsPluginRefineFlags, e.g. %GS_PLUGIN_REFINE_FLAGS_REQUIRE_SIZE
+ *
+ * Converts the flags to a string.
+ *
+ * Returns: a string
+ **/
+gchar *
+gs_plugin_refine_flags_to_string (GsPluginRefineFlags refine_flags)
+{
+	g_autoptr(GPtrArray) cstrs = g_ptr_array_new ();
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdiscarded-qualifiers"
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_ID)
+		g_ptr_array_add (cstrs, "require-id");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_LICENSE)
+		g_ptr_array_add (cstrs, "require-license");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_URL)
+		g_ptr_array_add (cstrs, "require-url");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_DESCRIPTION)
+		g_ptr_array_add (cstrs, "require-description");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_SIZE)
+		g_ptr_array_add (cstrs, "require-size");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_RATING)
+		g_ptr_array_add (cstrs, "require-rating");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_VERSION)
+		g_ptr_array_add (cstrs, "require-version");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_HISTORY)
+		g_ptr_array_add (cstrs, "require-history");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_SETUP_ACTION)
+		g_ptr_array_add (cstrs, "require-setup-action");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_UPDATE_DETAILS)
+		g_ptr_array_add (cstrs, "require-update-details");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN)
+		g_ptr_array_add (cstrs, "require-origin");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_RELATED)
+		g_ptr_array_add (cstrs, "require-related");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_ADDONS)
+		g_ptr_array_add (cstrs, "require-addons");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_ALLOW_PACKAGES)
+		g_ptr_array_add (cstrs, "require-allow-packages");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_UPDATE_SEVERITY)
+		g_ptr_array_add (cstrs, "require-update-severity");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_UPGRADE_REMOVED)
+		g_ptr_array_add (cstrs, "require-upgrade-removed");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_PROVENANCE)
+		g_ptr_array_add (cstrs, "require-provenance");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_REVIEWS)
+		g_ptr_array_add (cstrs, "require-reviews");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_REVIEW_RATINGS)
+		g_ptr_array_add (cstrs, "require-review-ratings");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_ICON)
+		g_ptr_array_add (cstrs, "require-icon");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_PERMISSIONS)
+		g_ptr_array_add (cstrs, "require-permissions");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN_HOSTNAME)
+		g_ptr_array_add (cstrs, "require-origin-hostname");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_ORIGIN_UI)
+		g_ptr_array_add (cstrs, "require-origin-ui");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_RUNTIME)
+		g_ptr_array_add (cstrs, "require-runtime");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_SCREENSHOTS)
+		g_ptr_array_add (cstrs, "require-screenshots");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_CATEGORIES)
+		g_ptr_array_add (cstrs, "require-categories");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_PROJECT_GROUP)
+		g_ptr_array_add (cstrs, "require-project-group");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_DEVELOPER_NAME)
+		g_ptr_array_add (cstrs, "require-developer-name");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_KUDOS)
+		g_ptr_array_add (cstrs, "require-kudos");
+	if (refine_flags & GS_PLUGIN_REFINE_FLAGS_REQUIRE_CONTENT_RATING)
+		g_ptr_array_add (cstrs, "content-rating");
+#pragma GCC diagnostic pop
+	if (cstrs->len == 0)
+		return g_strdup ("none");
+	g_ptr_array_add (cstrs, NULL);
+	return g_strjoinv (",", (gchar**) cstrs->pdata);
+}
+
+static void
+gs_plugin_constructed (GObject *object)
+{
+	GsPlugin *plugin = GS_PLUGIN (object);
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+
+	G_OBJECT_CLASS (gs_plugin_parent_class)->constructed (object);
+
+	/* Check all required properties have been set. */
+	g_assert (priv->session_bus_connection != NULL);
+	g_assert (priv->system_bus_connection != NULL);
+}
+
+static void
+gs_plugin_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
+{
+	GsPlugin *plugin = GS_PLUGIN (object);
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+
+	switch ((GsPluginProperty) prop_id) {
+	case PROP_FLAGS:
+		priv->flags = g_value_get_flags (value);
+		g_object_notify_by_pspec (G_OBJECT (plugin), obj_props[PROP_FLAGS]);
+		break;
+	case PROP_SESSION_BUS_CONNECTION:
+		/* Construct only */
+		g_assert (priv->session_bus_connection == NULL);
+		priv->session_bus_connection = g_value_dup_object (value);
+		break;
+	case PROP_SYSTEM_BUS_CONNECTION:
+		/* Construct only */
+		g_assert (priv->system_bus_connection == NULL);
+		priv->system_bus_connection = g_value_dup_object (value);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_plugin_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
+{
+	GsPlugin *plugin = GS_PLUGIN (object);
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+
+	switch ((GsPluginProperty) prop_id) {
+	case PROP_FLAGS:
+		g_value_set_flags (value, priv->flags);
+		break;
+	case PROP_SESSION_BUS_CONNECTION:
+		g_value_set_object (value, priv->session_bus_connection);
+		break;
+	case PROP_SYSTEM_BUS_CONNECTION:
+		g_value_set_object (value, priv->system_bus_connection);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_plugin_class_init (GsPluginClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+	object_class->constructed = gs_plugin_constructed;
+	object_class->set_property = gs_plugin_set_property;
+	object_class->get_property = gs_plugin_get_property;
+	object_class->dispose = gs_plugin_dispose;
+	object_class->finalize = gs_plugin_finalize;
+
+	/**
+	 * GsPlugin:flags:
+	 *
+	 * Flags which indicate various boolean properties of the plugin.
+	 *
+	 * These may change during the plugin’s lifetime.
+	 */
+	obj_props[PROP_FLAGS] =
+		g_param_spec_flags ("flags", NULL, NULL,
+				    GS_TYPE_PLUGIN_FLAGS, GS_PLUGIN_FLAGS_NONE,
+				    G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPlugin:session-bus-connection: (not nullable)
+	 *
+	 * A connection to the D-Bus session bus.
+	 *
+	 * This must be set at construction time and will not be %NULL
+	 * afterwards.
+	 *
+	 * Since: 43
+	 */
+	obj_props[PROP_SESSION_BUS_CONNECTION] =
+		g_param_spec_object ("session-bus-connection", NULL, NULL,
+				     G_TYPE_DBUS_CONNECTION,
+				     G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	/**
+	 * GsPlugin:system-bus-connection: (not nullable)
+	 *
+	 * A connection to the D-Bus system bus.
+	 *
+	 * This must be set at construction time and will not be %NULL
+	 * afterwards.
+	 *
+	 * Since: 43
+	 */
+	obj_props[PROP_SYSTEM_BUS_CONNECTION] =
+		g_param_spec_object ("system-bus-connection", NULL, NULL,
+				     G_TYPE_DBUS_CONNECTION,
+				     G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	g_object_class_install_properties (object_class, G_N_ELEMENTS (obj_props), obj_props);
+
+	signals [SIGNAL_UPDATES_CHANGED] =
+		g_signal_new ("updates-changed",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      G_STRUCT_OFFSET (GsPluginClass, updates_changed),
+			      NULL, NULL, g_cclosure_marshal_VOID__VOID,
+			      G_TYPE_NONE, 0);
+
+	signals [SIGNAL_STATUS_CHANGED] =
+		g_signal_new ("status-changed",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      G_STRUCT_OFFSET (GsPluginClass, status_changed),
+			      NULL, NULL, g_cclosure_marshal_generic,
+			      G_TYPE_NONE, 2, GS_TYPE_APP, G_TYPE_UINT);
+
+	signals [SIGNAL_RELOAD] =
+		g_signal_new ("reload",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      G_STRUCT_OFFSET (GsPluginClass, reload),
+			      NULL, NULL, g_cclosure_marshal_VOID__VOID,
+			      G_TYPE_NONE, 0);
+
+	signals [SIGNAL_REPORT_EVENT] =
+		g_signal_new ("report-event",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      G_STRUCT_OFFSET (GsPluginClass, report_event),
+			      NULL, NULL, g_cclosure_marshal_generic,
+			      G_TYPE_NONE, 1, GS_TYPE_PLUGIN_EVENT);
+
+	signals [SIGNAL_ALLOW_UPDATES] =
+		g_signal_new ("allow-updates",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      G_STRUCT_OFFSET (GsPluginClass, allow_updates),
+			      NULL, NULL, g_cclosure_marshal_VOID__BOOLEAN,
+			      G_TYPE_NONE, 1, G_TYPE_BOOLEAN);
+
+	signals [SIGNAL_BASIC_AUTH_START] =
+		g_signal_new ("basic-auth-start",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      G_STRUCT_OFFSET (GsPluginClass, basic_auth_start),
+			      NULL, NULL, g_cclosure_marshal_generic,
+			      G_TYPE_NONE, 4, G_TYPE_STRING, G_TYPE_STRING, G_TYPE_POINTER, G_TYPE_POINTER);
+
+	signals [SIGNAL_REPOSITORY_CHANGED] =
+		g_signal_new ("repository-changed",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      G_STRUCT_OFFSET (GsPluginClass, repository_changed),
+			      NULL, NULL, g_cclosure_marshal_generic,
+			      G_TYPE_NONE, 1, GS_TYPE_APP);
+
+	signals [SIGNAL_ASK_UNTRUSTED] =
+		g_signal_new ("ask-untrusted",
+			      G_TYPE_FROM_CLASS (object_class), G_SIGNAL_RUN_LAST,
+			      G_STRUCT_OFFSET (GsPluginClass, ask_untrusted),
+			      NULL, NULL, g_cclosure_marshal_generic,
+			      G_TYPE_BOOLEAN, 4, G_TYPE_STRING, G_TYPE_STRING, G_TYPE_STRING, G_TYPE_STRING);
+}
+
+static void
+gs_plugin_init (GsPlugin *plugin)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (plugin);
+	guint i;
+
+	for (i = 0; i < GS_PLUGIN_RULE_LAST; i++)
+		priv->rules[i] = g_ptr_array_new_with_free_func (g_free);
+
+	priv->enabled = TRUE;
+	priv->scale = 1;
+	priv->cache = g_hash_table_new_full ((GHashFunc) as_utils_data_id_hash,
+					     (GEqualFunc) as_utils_data_id_equal,
+					     g_free,
+					     (GDestroyNotify) g_object_unref);
+	priv->vfuncs = g_hash_table_new_full (g_str_hash, g_str_equal,
+					      g_free, NULL);
+	g_mutex_init (&priv->cache_mutex);
+	g_mutex_init (&priv->interactive_mutex);
+	g_mutex_init (&priv->timer_mutex);
+	g_mutex_init (&priv->vfuncs_mutex);
+}
+
+/**
+ * gs_plugin_new:
+ * @session_bus_connection: (not nullable) (transfer none): a session bus
+ *   connection to use
+ * @system_bus_connection: (not nullable) (transfer none): a system bus
+ *   connection to use
+ *
+ * Creates a new plugin.
+ *
+ * Returns: a #GsPlugin
+ *
+ * Since: 43
+ **/
+GsPlugin *
+gs_plugin_new (GDBusConnection *session_bus_connection,
+               GDBusConnection *system_bus_connection)
+{
+	g_return_val_if_fail (G_IS_DBUS_CONNECTION (session_bus_connection), NULL);
+	g_return_val_if_fail (G_IS_DBUS_CONNECTION (system_bus_connection), NULL);
+
+	return g_object_new (GS_TYPE_PLUGIN,
+			     "session-bus-connection", session_bus_connection,
+			     "system-bus-connection", system_bus_connection,
+			     NULL);
+}
+
+typedef struct {
+	GWeakRef  plugin_weak;  /* (owned) (element-type GsPlugin) */
+	GsApp	 *repository;  /* (owned) */
+} GsPluginRepositoryChangedHelper;
+
+static void
+gs_plugin_repository_changed_helper_free (GsPluginRepositoryChangedHelper *helper)
+{
+	g_clear_object (&helper->repository);
+	g_weak_ref_clear (&helper->plugin_weak);
+	g_slice_free (GsPluginRepositoryChangedHelper, helper);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (GsPluginRepositoryChangedHelper, gs_plugin_repository_changed_helper_free)
+
+static gboolean
+gs_plugin_repository_changed_cb (gpointer user_data)
+{
+	GsPluginRepositoryChangedHelper *helper = user_data;
+	g_autoptr(GsPlugin) plugin = NULL;
+
+	plugin = g_weak_ref_get (&helper->plugin_weak);
+	if (plugin != NULL)
+		g_signal_emit (plugin,
+			       signals[SIGNAL_REPOSITORY_CHANGED], 0,
+			       helper->repository);
+
+	return G_SOURCE_REMOVE;
+}
+
+/**
+ * gs_plugin_repository_changed:
+ * @plugin: a #GsPlugin
+ * @repository: a #GsApp representing the repository
+ *
+ * Emit the "repository-changed" signal in the main thread.
+ *
+ * Since: 40
+ **/
+void
+gs_plugin_repository_changed (GsPlugin *plugin,
+			      GsApp *repository)
+{
+	g_autoptr(GsPluginRepositoryChangedHelper) helper = NULL;
+	g_autoptr(GSource) idle_source = NULL;
+
+	g_return_if_fail (GS_IS_PLUGIN (plugin));
+	g_return_if_fail (GS_IS_APP (repository));
+
+	helper = g_slice_new0 (GsPluginRepositoryChangedHelper);
+	g_weak_ref_init (&helper->plugin_weak, plugin);
+	helper->repository = g_object_ref (repository);
+
+	idle_source = g_idle_source_new ();
+	g_source_set_callback (idle_source, gs_plugin_repository_changed_cb, g_steal_pointer (&helper), (GDestroyNotify) gs_plugin_repository_changed_helper_free);
+	g_source_attach (idle_source, NULL);
+}
+
+/**
+ * gs_plugin_update_cache_state_for_repository:
+ * @plugin: a #GsPlugin
+ * @repository: a #GsApp representing a repository, which changed
+ *
+ * Update state of the all cached #GsApp instances related
+ * to the @repository.
+ *
+ * Since: 40
+ **/
+void
+gs_plugin_update_cache_state_for_repository (GsPlugin *plugin,
+					     GsApp *repository)
+{
+	GsPluginPrivate *priv;
+	GHashTableIter iter;
+	g_autoptr(GMutexLocker) locker = NULL;
+	g_autoptr(GsPlugin) repo_plugin = NULL;
+	gpointer value;
+	const gchar *repo_id;
+	GsAppState repo_state;
+
+	g_return_if_fail (GS_IS_PLUGIN (plugin));
+	g_return_if_fail (GS_IS_APP (repository));
+
+	priv = gs_plugin_get_instance_private (plugin);
+	repo_id = gs_app_get_id (repository);
+	repo_state = gs_app_get_state (repository);
+	repo_plugin = gs_app_dup_management_plugin (repository);
+
+	locker = g_mutex_locker_new (&priv->cache_mutex);
+
+	g_hash_table_iter_init (&iter, priv->cache);
+	while (g_hash_table_iter_next (&iter, NULL, &value)) {
+		GsApp *app = value;
+		GsAppState app_state = gs_app_get_state (app);
+		g_autoptr(GsPlugin) app_plugin = gs_app_dup_management_plugin (app);
+
+		if (app_plugin != repo_plugin ||
+		    gs_app_get_scope (app) != gs_app_get_scope (repository) ||
+		    gs_app_get_bundle_kind (app) != gs_app_get_bundle_kind (repository))
+			continue;
+
+		if (((app_state == GS_APP_STATE_AVAILABLE &&
+		    repo_state != GS_APP_STATE_INSTALLED) ||
+		    (app_state == GS_APP_STATE_UNAVAILABLE &&
+		    repo_state == GS_APP_STATE_INSTALLED)) &&
+		    g_strcmp0 (gs_app_get_origin (app), repo_id) == 0) {
+			/* First reset the state, because move from 'available' to 'unavailable' is not correct */
+			gs_app_set_state (app, GS_APP_STATE_UNKNOWN);
+			gs_app_set_state (app, repo_state == GS_APP_STATE_INSTALLED ? GS_APP_STATE_AVAILABLE : GS_APP_STATE_UNAVAILABLE);
+		}
+	}
+}
+
+/**
+ * gs_plugin_ask_untrusted:
+ * @plugin: a #GsPlugin
+ * @title: the title for the question
+ * @msg: the message for the question
+ * @details: (nullable): the detailed error message, or %NULL for none
+ * @accept_label: (nullable): a label of the 'accept' button, or %NULL to use 'Accept'
+ *
+ * Asks the user whether he/she accepts an untrusted package install/download/update,
+ * as described by @title and @msg, eventually with the @details.
+ *
+ * Note: This is a blocking call and can be called only from the main/GUI thread.
+ *
+ * Returns: whether the user accepted the question
+ *
+ * Since: 42
+ **/
+gboolean
+gs_plugin_ask_untrusted (GsPlugin *plugin,
+			 const gchar *title,
+			 const gchar *msg,
+			 const gchar *details,
+			 const gchar *accept_label)
+{
+	gboolean accepts = FALSE;
+	g_signal_emit (plugin,
+		       signals[SIGNAL_ASK_UNTRUSTED], 0,
+		       title,
+		       msg,
+		       details,
+		       accept_label,
+		       &accepts);
+	return accepts;
+}
+
+/**
+ * gs_plugin_get_session_bus_connection:
+ * @self: a #GsPlugin
+ *
+ * Get the D-Bus session bus connection in use by the plugin.
+ *
+ * Returns: (transfer none) (not nullable): a D-Bus connection
+ * Since: 43
+ */
+GDBusConnection *
+gs_plugin_get_session_bus_connection (GsPlugin *self)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (self);
+
+	g_return_val_if_fail (GS_IS_PLUGIN (self), NULL);
+
+	return priv->session_bus_connection;
+}
+
+/**
+ * gs_plugin_get_system_bus_connection:
+ * @self: a #GsPlugin
+ *
+ * Get the D-Bus system bus connection in use by the plugin.
+ *
+ * Returns: (transfer none) (not nullable): a D-Bus connection
+ * Since: 43
+ */
+GDBusConnection *
+gs_plugin_get_system_bus_connection (GsPlugin *self)
+{
+	GsPluginPrivate *priv = gs_plugin_get_instance_private (self);
+
+	g_return_val_if_fail (GS_IS_PLUGIN (self), NULL);
+
+	return priv->system_bus_connection;
+}
diff --git a/lib/gs-plugin.h b/lib/gs-plugin.h
new file mode 100644
index 0000000..87dd858
--- /dev/null
+++ b/lib/gs-plugin.h
@@ -0,0 +1,331 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2012-2016 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2020 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib-object.h>
+#include <gmodule.h>
+#include <gio/gio.h>
+
+#include "gs-app.h"
+#include "gs-app-list.h"
+#include "gs-app-query.h"
+#include "gs-category.h"
+#include "gs-plugin-event.h"
+#include "gs-plugin-types.h"
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_PLUGIN (gs_plugin_get_type ())
+
+G_DECLARE_DERIVABLE_TYPE (GsPlugin, gs_plugin, GS, PLUGIN, GObject)
+
+/**
+ * GsPluginClass:
+ * @setup_async: (nullable): Setup method for the plugin. This is called after
+ *   the #GsPlugin object is constructed, before it’s used for anything. It
+ *   should do any long-running setup operations which the plugin needs, such as
+ *   file or network access. It may be %NULL if the plugin doesn’t need to be
+ *   explicitly shut down. It is not called if the plugin is disabled during
+ *   construction.
+ * @setup_finish: (nullable): Finish method for @setup_async. Must be
+ *   implemented if @setup_async is implemented. If this returns an error, the
+ *   plugin will be disabled.
+ * @shutdown_async: (nullable): Shutdown method for the plugin. This is called
+ *   by the #GsPluginLoader when the process is terminating or the
+ *   #GsPluginLoader is being destroyed. It should be used to cancel or stop any
+ *   ongoing operations or threads in the plugin. It may be %NULL if the plugin
+ *   doesn’t need to be explicitly shut down.
+ * @shutdown_finish: (nullable): Finish method for @shutdown_async. Must be
+ *   implemented if @shutdown_async is implemented.
+ * @refine_async: (nullable): Refining looks up and adds data to #GsApps. The
+ *   apps to refine are provided in a list, and the flags specify what data to
+ *   look up and add. Refining certain kinds of data can be very expensive (for
+ *   example, requiring network requests), which is why it’s not all loaded by
+ *   default. By refining multiple applications at once, data requests can be
+ *   batched by the plugin where possible. (Since: 43)
+ * @refine_finish: (nullable): Finish method for @refine_async. Must be
+ *   implemented if @refine_async is implemented. (Since: 43)
+ * @list_apps_async: (nullable): List apps matching a given query. (Since: 43)
+ * @list_apps_finish: (nullable): Finish method for @list_apps_async. Must be
+ *   implemented if @list_apps_async is implemented. (Since: 43)
+ * @refresh_metadata_async: (nullable): Refresh plugin metadata. (Since: 43)
+ * @refresh_metadata_finish: (nullable): Finish method for
+ *   @refresh_metadata_async. Must be implemented if @refresh_metadata_async is
+ *   implemented. (Since: 43)
+ * @list_distro_upgrades_async: (nullable): List available distro upgrades. (Since: 43)
+ * @list_distro_upgrades_finish: (nullable): Finish method for
+ *   @list_distro_upgrades_async. Must be implemented if
+ *   @list_distro_upgrades_async is implemented. (Since: 43)
+ * @install_repository_async: (nullable): Install repository. (Since: 43)
+ * @install_repository_finish: (nullable): Finish method for
+ *   @install_repository_async. Must be implemented if
+ *   @install_repository_async is implemented. (Since: 43)
+ * @remove_repository_async: (nullable): Remove repository. (Since: 43)
+ * @remove_repository_finish: (nullable): Finish method for
+ *   @remove_repository_async. Must be implemented if
+ *   @remove_repository_async is implemented. (Since: 43)
+ * @enable_repository_async: (nullable): Enable repository. (Since: 43)
+ * @enable_repository_finish: (nullable): Finish method for
+ *   @enable_repository_async. Must be implemented if
+ *   @enable_repository_async is implemented. (Since: 43)
+ * @disable_repository_async: (nullable): Disable repository. (Since: 43)
+ * @disable_repository_finish: (nullable): Finish method for
+ *   @disable_repository_async. Must be implemented if
+ *   @disable_repository_async is implemented. (Since: 43)
+ * @refine_categories_async: (nullable): Refining looks up and adds data to
+ *   #GsCategorys. The categories to refine are provided in a list, and the
+ *   flags specify what data to look up and add. Refining certain kinds of data
+ *   can be very expensive (for example, requiring network requests), which is
+ *   why it’s not all loaded by default. By refining multiple categories at
+ *   once, data requests can be batched by the plugin where possible. (Since: 43)
+ * @refine_categories_finish: (nullable): Finish method for
+ *   @refine_categories_async. Must be implemented if @refine_categories_async
+ *   is implemented. (Since: 43)
+ *
+ * The class structure for a #GsPlugin. Virtual methods here should be
+ * implemented by plugin implementations derived from #GsPlugin to provide their
+ * plugin-specific behaviour.
+ */
+struct _GsPluginClass
+{
+	GObjectClass		 parent_class;
+	void			(*updates_changed)	(GsPlugin	*plugin);
+	void			(*status_changed)	(GsPlugin	*plugin,
+							 GsApp		*app,
+							 guint		 status);
+	void			(*reload)		(GsPlugin	*plugin);
+	void			(*report_event)		(GsPlugin	*plugin,
+							 GsPluginEvent	*event);
+	void			(*allow_updates)	(GsPlugin	*plugin,
+							 gboolean	 allow_updates);
+	void			(*basic_auth_start)	(GsPlugin	*plugin,
+							 const gchar	*remote,
+							 const gchar	*realm,
+							 GCallback	 callback,
+							 gpointer	 user_data);
+	void			(*repository_changed)	(GsPlugin	*plugin,
+							 GsApp		*repository);
+	gboolean		(*ask_untrusted)	(GsPlugin	*plugin,
+							 const gchar	*title,
+							 const gchar	*msg,
+							 const gchar	*details,
+							 const gchar	*accept_label);
+
+	void			(*setup_async)		(GsPlugin		*plugin,
+							 GCancellable		*cancellable,
+							 GAsyncReadyCallback	 callback,
+							 gpointer		 user_data);
+	gboolean		(*setup_finish)		(GsPlugin		*plugin,
+							 GAsyncResult		*result,
+							 GError			**error);
+
+	void			(*shutdown_async)	(GsPlugin		*plugin,
+							 GCancellable		*cancellable,
+							 GAsyncReadyCallback	 callback,
+							 gpointer		 user_data);
+	gboolean		(*shutdown_finish)	(GsPlugin		*plugin,
+							 GAsyncResult		*result,
+							 GError			**error);
+
+	void			(*refine_async)		(GsPlugin		*plugin,
+							 GsAppList		*list,
+							 GsPluginRefineFlags	 flags,
+							 GCancellable		*cancellable,
+							 GAsyncReadyCallback	 callback,
+							 gpointer		 user_data);
+	gboolean		(*refine_finish)	(GsPlugin		*plugin,
+							 GAsyncResult		*result,
+							 GError			**error);
+
+	void			(*list_apps_async)		(GsPlugin		*plugin,
+								 GsAppQuery		*query,
+								 GsPluginListAppsFlags	 flags,
+								 GCancellable		*cancellable,
+								 GAsyncReadyCallback	 callback,
+								 gpointer		 user_data);
+	GsAppList *		(*list_apps_finish)		(GsPlugin		*plugin,
+								 GAsyncResult		*result,
+								 GError			**error);
+
+	void			(*refresh_metadata_async)	(GsPlugin		*plugin,
+								 guint64		 cache_age_secs,
+								 GsPluginRefreshMetadataFlags flags,
+								 GCancellable		*cancellable,
+								 GAsyncReadyCallback	 callback,
+								 gpointer		 user_data);
+	gboolean		(*refresh_metadata_finish)	(GsPlugin		*plugin,
+								 GAsyncResult		*result,
+								 GError			**error);
+
+	void			(*list_distro_upgrades_async)	(GsPlugin		*plugin,
+								 GsPluginListDistroUpgradesFlags flags,
+								 GCancellable		*cancellable,
+								 GAsyncReadyCallback	 callback,
+								 gpointer		 user_data);
+	GsAppList *		(*list_distro_upgrades_finish)	(GsPlugin		*plugin,
+								 GAsyncResult		*result,
+								 GError			**error);
+
+	void			(*install_repository_async)	(GsPlugin		*plugin,
+								 GsApp			*repository,
+								 GsPluginManageRepositoryFlags flags,
+								 GCancellable		*cancellable,
+								 GAsyncReadyCallback	 callback,
+								 gpointer		 user_data);
+	gboolean		(*install_repository_finish)	(GsPlugin		*plugin,
+								 GAsyncResult		*result,
+								 GError			**error);
+	void			(*remove_repository_async)	(GsPlugin		*plugin,
+								 GsApp			*repository,
+								 GsPluginManageRepositoryFlags flags,
+								 GCancellable		*cancellable,
+								 GAsyncReadyCallback	 callback,
+								 gpointer		 user_data);
+	gboolean		(*remove_repository_finish)	(GsPlugin		*plugin,
+								 GAsyncResult		*result,
+								 GError			**error);
+	void			(*enable_repository_async)	(GsPlugin		*plugin,
+								 GsApp			*repository,
+								 GsPluginManageRepositoryFlags flags,
+								 GCancellable		*cancellable,
+								 GAsyncReadyCallback	 callback,
+								 gpointer		 user_data);
+	gboolean		(*enable_repository_finish)	(GsPlugin		*plugin,
+								 GAsyncResult		*result,
+								 GError			**error);
+	void			(*disable_repository_async)	(GsPlugin		*plugin,
+								 GsApp			*repository,
+								 GsPluginManageRepositoryFlags flags,
+								 GCancellable		*cancellable,
+								 GAsyncReadyCallback	 callback,
+								 gpointer		 user_data);
+	gboolean		(*disable_repository_finish)	(GsPlugin		*plugin,
+								 GAsyncResult		*result,
+								 GError			**error);
+
+	void			(*refine_categories_async)	(GsPlugin			*plugin,
+								 GPtrArray			*list,
+								 GsPluginRefineCategoriesFlags	 flags,
+								 GCancellable			*cancellable,
+								 GAsyncReadyCallback		 callback,
+								 gpointer			 user_data);
+	gboolean		(*refine_categories_finish)	(GsPlugin			*plugin,
+								 GAsyncResult			*result,
+								 GError				**error);
+
+	gpointer		 padding[23];
+};
+
+/* helpers */
+#define	GS_PLUGIN_ERROR					gs_plugin_error_quark ()
+
+GQuark		 gs_plugin_error_quark			(void);
+
+/* public getters and setters */
+const gchar	*gs_plugin_get_name			(GsPlugin	*plugin);
+const gchar	*gs_plugin_get_appstream_id		(GsPlugin	*plugin);
+void		 gs_plugin_set_appstream_id		(GsPlugin	*plugin,
+							 const gchar	*appstream_id);
+gboolean	 gs_plugin_get_enabled			(GsPlugin	*plugin);
+void		 gs_plugin_set_enabled			(GsPlugin	*plugin,
+							 gboolean	 enabled);
+gboolean	 gs_plugin_has_flags			(GsPlugin	*plugin,
+							 GsPluginFlags	 flags);
+void		 gs_plugin_add_flags			(GsPlugin	*plugin,
+							 GsPluginFlags	 flags);
+void		 gs_plugin_remove_flags			(GsPlugin	*plugin,
+							 GsPluginFlags	 flags);
+guint		 gs_plugin_get_scale			(GsPlugin	*plugin);
+const gchar	*gs_plugin_get_language			(GsPlugin	*plugin);
+void		 gs_plugin_add_rule			(GsPlugin	*plugin,
+							 GsPluginRule	 rule,
+							 const gchar	*name);
+
+/* helpers */
+gboolean	 gs_plugin_download_file		(GsPlugin	*plugin,
+							 GsApp		*app,
+							 const gchar	*uri,
+							 const gchar	*filename,
+							 GCancellable	*cancellable,
+							 GError		**error);
+gchar		*gs_plugin_download_rewrite_resource	(GsPlugin	*plugin,
+							 GsApp		*app,
+							 const gchar	*resource,
+							 GCancellable	*cancellable,
+							 GError		**error);
+
+gboolean	 gs_plugin_check_distro_id		(GsPlugin	*plugin,
+							 const gchar	*distro_id);
+GsApp		*gs_plugin_cache_lookup			(GsPlugin	*plugin,
+							 const gchar	*key);
+void		 gs_plugin_cache_lookup_by_state	(GsPlugin	*plugin,
+							 GsAppList	*list,
+							 GsAppState	 state);
+void		 gs_plugin_cache_add			(GsPlugin	*plugin,
+							 const gchar	*key,
+							 GsApp		*app);
+void		 gs_plugin_cache_remove			(GsPlugin	*plugin,
+							 const gchar	*key);
+void		 gs_plugin_cache_invalidate		(GsPlugin	*plugin);
+void		 gs_plugin_status_update		(GsPlugin	*plugin,
+							 GsApp		*app,
+							 GsPluginStatus	 status);
+gboolean	 gs_plugin_app_launch			(GsPlugin	*plugin,
+							 GsApp		*app,
+							 GError		**error);
+typedef gboolean (* GsPluginPickDesktopFileCallback)	(GsPlugin	*plugin,
+							 GsApp		*app,
+							 const gchar	*filename,
+							 GKeyFile	*key_file);
+/**
+ * GsPluginPickDesktopFileCallback:
+ * @plugin: a #GsPlugin
+ * @app: a #GsApp
+ * @filename: a .desktop file name
+ * @key_file: a #GKeyFile with @filename loaded
+ *
+ * A callback used by gs_plugin_app_launch_filtered() to filter which
+ * of the candidate .desktop files should be used to launch the @app.
+ *
+ * Returns: %TRUE, when the @key_file should be used, %FALSE to continue
+ *    searching.
+ *
+ * Since: 43
+ **/
+gboolean	 gs_plugin_app_launch_filtered		(GsPlugin	*plugin,
+							 GsApp		*app,
+							 GsPluginPickDesktopFileCallback cb,
+							 gpointer	user_data,
+							 GError		**error);
+void		 gs_plugin_updates_changed		(GsPlugin	*plugin);
+void		 gs_plugin_reload			(GsPlugin	*plugin);
+const gchar	*gs_plugin_status_to_string		(GsPluginStatus	 status);
+void		 gs_plugin_report_event			(GsPlugin	*plugin,
+							 GsPluginEvent	*event);
+void		 gs_plugin_set_allow_updates		(GsPlugin	*plugin,
+							 gboolean	 allow_updates);
+gboolean	 gs_plugin_get_network_available	(GsPlugin	*plugin);
+void		 gs_plugin_basic_auth_start		(GsPlugin	*plugin,
+							 const gchar	*remote,
+							 const gchar	*realm,
+							 GCallback	 callback,
+							 gpointer	 user_data);
+void		gs_plugin_repository_changed		(GsPlugin	*plugin,
+							 GsApp		*repository);
+void		gs_plugin_update_cache_state_for_repository
+							(GsPlugin *plugin,
+							 GsApp *repository);
+gboolean	gs_plugin_ask_untrusted			(GsPlugin	*plugin,
+							 const gchar	*title,
+							 const gchar	*msg,
+							 const gchar	*details,
+							 const gchar	*accept_label);
+
+G_END_DECLS
diff --git a/lib/gs-remote-icon.c b/lib/gs-remote-icon.c
new file mode 100644
index 0000000..84b071b
--- /dev/null
+++ b/lib/gs-remote-icon.c
@@ -0,0 +1,375 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Endless OS Foundation, Inc
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-remote-icon
+ * @short_description: A #GIcon implementation for remote icons
+ *
+ * #GsRemoteIcon is a #GIcon implementation which represents remote icons —
+ * icons which have an HTTP or HTTPS URI. It provides a well-known local filename
+ * for a cached copy of the icon, accessible as #GFileIcon:file, and a method
+ * to download the icon to the cache, gs_remote_icon_ensure_cached().
+ *
+ * Constructing a #GsRemoteIcon does not guarantee that the icon is cached. Call
+ * gs_remote_icon_ensure_cached() for that.
+ *
+ * #GsRemoteIcon is immutable after construction and hence is entirely thread
+ * safe.
+ *
+ * FIXME: Currently does no cache invalidation.
+ *
+ * Since: 40
+ */
+
+#include "config.h"
+
+#include <gio/gio.h>
+#include <glib.h>
+#include <glib-object.h>
+#include <glib/gstdio.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <libsoup/soup.h>
+
+#include "gs-remote-icon.h"
+#include "gs-utils.h"
+
+/* FIXME: Work around the fact that GFileIcon is not derivable, by deriving from
+ * it anyway by copying its `struct GFileIcon` definition inline here. This will
+ * work as long as the size of `struct GFileIcon` doesn’t change within GIO.
+ * There’s no way of knowing if that’s the case.
+ *
+ * See https://gitlab.gnome.org/GNOME/glib/-/issues/2345 for why this is
+ * necessary. */
+struct _GsRemoteIcon
+{
+	/* struct GFileIcon { */
+	GObject		 grandparent;
+	GFile		*file;
+	/* } */
+
+	gchar		*uri;  /* (owned), immutable after construction */
+};
+
+G_DEFINE_TYPE (GsRemoteIcon, gs_remote_icon, G_TYPE_FILE_ICON)
+
+typedef enum {
+	PROP_URI = 1,
+} GsRemoteIconProperty;
+
+static GParamSpec *obj_props[PROP_URI + 1] = { NULL, };
+
+static void
+gs_remote_icon_get_property (GObject    *object,
+                             guint       prop_id,
+                             GValue     *value,
+                             GParamSpec *pspec)
+{
+	GsRemoteIcon *self = GS_REMOTE_ICON (object);
+
+	switch ((GsRemoteIconProperty) prop_id) {
+	case PROP_URI:
+		g_value_set_string (value, gs_remote_icon_get_uri (self));
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_remote_icon_set_property (GObject      *object,
+                             guint         prop_id,
+                             const GValue *value,
+                             GParamSpec   *pspec)
+{
+	GsRemoteIcon *self = GS_REMOTE_ICON (object);
+
+	switch ((GsRemoteIconProperty) prop_id) {
+	case PROP_URI:
+		/* Construct only */
+		g_assert (self->uri == NULL);
+		self->uri = g_value_dup_string (value);
+		g_assert (g_str_has_prefix (self->uri, "http:") ||
+			  g_str_has_prefix (self->uri, "https:"));
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_remote_icon_finalize (GObject *object)
+{
+	GsRemoteIcon *self = GS_REMOTE_ICON (object);
+
+	g_free (self->uri);
+
+	G_OBJECT_CLASS (gs_remote_icon_parent_class)->finalize (object);
+}
+
+static void
+gs_remote_icon_class_init (GsRemoteIconClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+	object_class->get_property = gs_remote_icon_get_property;
+	object_class->set_property = gs_remote_icon_set_property;
+	object_class->finalize = gs_remote_icon_finalize;
+
+	/**
+	 * GsRemoteIcon:uri: (not nullable)
+	 *
+	 * Remote URI of the icon. This must be an HTTP or HTTPS URI; it is a
+	 * programmer error to provide other URI schemes.
+	 *
+	 * Since: 40
+	 */
+	obj_props[PROP_URI] =
+		g_param_spec_string ("uri", NULL, NULL,
+				     NULL,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+	g_object_class_install_properties (object_class, G_N_ELEMENTS (obj_props), obj_props);
+}
+
+static void
+gs_remote_icon_init (GsRemoteIcon *self)
+{
+}
+
+/* Use a hash-prefixed filename to avoid cache clashes.
+ * This can only fail if @create_directory is %TRUE. */
+static gchar *
+gs_remote_icon_get_cache_filename (const gchar  *uri,
+                                   gboolean      create_directory,
+                                   GError      **error)
+{
+	g_autofree gchar *uri_checksum = NULL;
+	g_autofree gchar *uri_basename = NULL;
+	g_autofree gchar *cache_basename = NULL;
+	GsUtilsCacheFlags flags;
+
+	uri_checksum = g_compute_checksum_for_string (G_CHECKSUM_SHA1,
+						      uri,
+						      -1);
+	uri_basename = g_path_get_basename (uri);
+
+	/* convert filename from jpg to png, as we always convert to PNG on
+	 * download */
+	if (g_str_has_suffix (uri_basename, ".jpg"))
+		memcpy (uri_basename + strlen (uri_basename) - 4, ".png", 4);
+
+	cache_basename = g_strdup_printf ("%s-%s", uri_checksum, uri_basename);
+
+	flags = GS_UTILS_CACHE_FLAG_WRITEABLE;
+	if (create_directory)
+		flags |= GS_UTILS_CACHE_FLAG_CREATE_DIRECTORY;
+
+	return gs_utils_get_cache_filename ("icons",
+					    cache_basename,
+					    flags,
+					    error);
+}
+
+/**
+ * gs_remote_icon_new:
+ * @uri: remote URI of the icon
+ *
+ * Create a new #GsRemoteIcon representing @uri. The #GFileIcon:file of the
+ * resulting icon will represent the local cache location for the icon.
+ *
+ * Returns: (transfer full): a new remote icon
+ * Since: 40
+ */
+GIcon *
+gs_remote_icon_new (const gchar *uri)
+{
+	g_autofree gchar *cache_filename = NULL;
+	g_autoptr(GFile) file = NULL;
+
+	g_return_val_if_fail (uri != NULL, NULL);
+
+	/* The file is the expected cached location of the icon, once it’s
+	 * downloaded. By setting it as the #GFileIcon:file property, existing
+	 * code (particularly in GTK) which operates on #GFileIcons will work
+	 * transparently with this.
+	 *
+	 * Ideally, #GFileIcon would be an interface rather than a class, which
+	 * would make this implementation cleaner, but this is what we’re stuck
+	 * with.
+	 *
+	 * See https://gitlab.gnome.org/GNOME/glib/-/issues/2345 */
+	cache_filename = gs_remote_icon_get_cache_filename (uri, FALSE, NULL);
+	g_assert (cache_filename != NULL);
+	file = g_file_new_for_path (cache_filename);
+
+	return g_object_new (GS_TYPE_REMOTE_ICON,
+			     "file", file,
+			     "uri", uri,
+			     NULL);
+}
+
+/**
+ * gs_remote_icon_get_uri:
+ * @self: a #GsRemoteIcon
+ *
+ * Gets the value of #GsRemoteIcon:uri.
+ *
+ * Returns: (not nullable): remote URI of the icon
+ * Since: 40
+ */
+const gchar *
+gs_remote_icon_get_uri (GsRemoteIcon *self)
+{
+	g_return_val_if_fail (GS_IS_REMOTE_ICON (self), NULL);
+
+	return self->uri;
+}
+
+static GdkPixbuf *
+gs_icon_download (SoupSession   *session,
+                  const gchar   *uri,
+                  const gchar   *destination_path,
+                  guint          max_size,
+                  GCancellable  *cancellable,
+                  GError       **error)
+{
+	guint status_code;
+	g_autoptr(SoupMessage) msg = NULL;
+	g_autoptr(GInputStream) stream = NULL;
+	g_autoptr(GdkPixbuf) pixbuf = NULL;
+	g_autoptr(GdkPixbuf) scaled_pixbuf = NULL;
+
+	/* Create the request */
+	msg = soup_message_new (SOUP_METHOD_GET, uri);
+	if (msg == NULL) {
+		g_set_error_literal (error,
+				     G_IO_ERROR,
+				     G_IO_ERROR_INVALID_DATA,
+				     "Icon has an invalid URL");
+		return NULL;
+	}
+
+	/* Send request synchronously and start reading the response. */
+	stream = soup_session_send (session, msg, cancellable, error);
+
+#if SOUP_CHECK_VERSION(3, 0, 0)
+	status_code = soup_message_get_status (msg);
+#else
+	status_code = msg->status_code;
+#endif
+	if (stream == NULL) {
+		return NULL;
+	} else if (status_code != SOUP_STATUS_OK) {
+		g_set_error (error,
+			     G_IO_ERROR,
+			     G_IO_ERROR_FAILED,
+			     "Failed to download icon %s: %s",
+			     uri, soup_status_get_phrase (status_code));
+		return NULL;
+	}
+
+	/* Typically these icons are 64x64px PNG files. If not, resize down
+	 * so it’s at most @max_size square, to minimise the size of the on-disk
+	 * cache.*/
+	pixbuf = gdk_pixbuf_new_from_stream (stream, cancellable, error);
+	if (pixbuf == NULL)
+		return NULL;
+
+	if ((guint) gdk_pixbuf_get_height (pixbuf) <= max_size &&
+	    (guint) gdk_pixbuf_get_width (pixbuf) <= max_size) {
+		scaled_pixbuf = g_object_ref (pixbuf);
+	} else {
+		scaled_pixbuf = gdk_pixbuf_scale_simple (pixbuf, max_size, max_size,
+							 GDK_INTERP_BILINEAR);
+	}
+
+	/* write file */
+	if (!gdk_pixbuf_save (scaled_pixbuf, destination_path, "png", error, NULL))
+		return NULL;
+
+	return g_steal_pointer (&scaled_pixbuf);
+}
+
+/**
+ * gs_remote_icon_ensure_cached:
+ * @self: a #GsRemoteIcon
+ * @soup_session: a #SoupSession to use to download the icon
+ * @maximum_icon_size: maximum size (in device pixels) of the icon to save
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @error: return location for a #GError, or %NULL
+ *
+ * Ensure the given icon is present in the local cache, potentially downloading
+ * it from its remote server if needed. This will do network and disk I/O.
+ *
+ * @maximum_icon_size specifies the maximum size (in device pixels) of the icon
+ * which should be saved to the cache. This is the maximum size that the icon
+ * can ever be used at, as icons can be downscaled but never upscaled. Typically
+ * this will be 160px multiplied by the device scale
+ * (`gtk_widget_get_scale_factor()`).
+ *
+ * This can be called from any thread, as #GsRemoteIcon is immutable and hence
+ * thread-safe.
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 40
+ */
+gboolean
+gs_remote_icon_ensure_cached (GsRemoteIcon  *self,
+                              SoupSession   *soup_session,
+                              guint          maximum_icon_size,
+                              GCancellable  *cancellable,
+                              GError       **error)
+{
+	const gchar *uri;
+	g_autofree gchar *cache_filename = NULL;
+	g_autoptr(GdkPixbuf) cached_pixbuf = NULL;
+	GStatBuf stat_buf;
+
+	g_return_val_if_fail (GS_IS_REMOTE_ICON (self), FALSE);
+	g_return_val_if_fail (SOUP_IS_SESSION (soup_session), FALSE);
+	g_return_val_if_fail (maximum_icon_size > 0, FALSE);
+	g_return_val_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable), FALSE);
+	g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
+
+	uri = gs_remote_icon_get_uri (self);
+
+	/* Work out cache filename. */
+	cache_filename = gs_remote_icon_get_cache_filename (uri, TRUE, error);
+	if (cache_filename == NULL)
+		return FALSE;
+
+	/* Already in cache and not older than 30 days */
+	if (g_stat (cache_filename, &stat_buf) != -1 &&
+	    S_ISREG (stat_buf.st_mode) &&
+	    (g_get_real_time () / G_USEC_PER_SEC) - stat_buf.st_mtim.tv_sec < (60 * 60 * 24 * 30)) {
+		gint width = 0, height = 0;
+		/* Ensure the downloaded image dimensions are stored on the icon */
+		if (!g_object_get_data (G_OBJECT (self), "width") &&
+		    gdk_pixbuf_get_file_info (cache_filename, &width, &height)) {
+			g_object_set_data (G_OBJECT (self), "width", GINT_TO_POINTER (width));
+			g_object_set_data (G_OBJECT (self), "height", GINT_TO_POINTER (height));
+		}
+		return TRUE;
+	}
+
+	cached_pixbuf = gs_icon_download (soup_session, uri, cache_filename, maximum_icon_size, cancellable, error);
+	if (cached_pixbuf == NULL)
+		return FALSE;
+
+	/* Ensure the dimensions are set correctly on the icon. */
+	g_object_set_data (G_OBJECT (self), "width", GUINT_TO_POINTER (gdk_pixbuf_get_width (cached_pixbuf)));
+	g_object_set_data (G_OBJECT (self), "height", GUINT_TO_POINTER (gdk_pixbuf_get_height (cached_pixbuf)));
+
+	return TRUE;
+}
diff --git a/lib/gs-remote-icon.h b/lib/gs-remote-icon.h
new file mode 100644
index 0000000..82e246f
--- /dev/null
+++ b/lib/gs-remote-icon.h
@@ -0,0 +1,37 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Endless OS Foundation, Inc
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <gio/gio.h>
+#include <glib.h>
+#include <glib-object.h>
+#include <libsoup/soup.h>
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_REMOTE_ICON (gs_remote_icon_get_type ())
+
+/* FIXME: This is actually derived from GFileIcon, but the GFileIconClass isn’t
+ * public, so we use GObjectClass instead (which is what GFileIconClass is — it
+ * doesn’t define any vfuncs). See the note in gs-remote-icon.c. */
+G_DECLARE_FINAL_TYPE (GsRemoteIcon, gs_remote_icon, GS, REMOTE_ICON, GObject)
+
+GIcon		*gs_remote_icon_new		(const gchar		 *uri);
+
+const gchar	*gs_remote_icon_get_uri		(GsRemoteIcon		 *self);
+
+gboolean	 gs_remote_icon_ensure_cached	(GsRemoteIcon		 *self,
+						 SoupSession		 *soup_session,
+						 guint			  maximum_icon_size,
+						 GCancellable		 *cancellable,
+						 GError			**error);
+
+G_END_DECLS
diff --git a/lib/gs-self-test.c b/lib/gs-self-test.c
new file mode 100644
index 0000000..c38f452
--- /dev/null
+++ b/lib/gs-self-test.c
@@ -0,0 +1,786 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2013-2017 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2015-2018 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include "config.h"
+
+#include "gnome-software-private.h"
+
+#include "gs-debug.h"
+#include "gs-test.h"
+
+static gboolean
+gs_app_list_filter_cb (GsApp *app, gpointer user_data)
+{
+	if (g_strcmp0 (gs_app_get_id (app), "a") == 0)
+		return FALSE;
+	if (g_strcmp0 (gs_app_get_id (app), "c") == 0)
+		return FALSE;
+	return TRUE;
+}
+
+static void
+gs_utils_url_func (void)
+{
+	g_autofree gchar *path1 = NULL;
+	g_autofree gchar *path2 = NULL;
+	g_autofree gchar *path3 = NULL;
+	g_autofree gchar *scheme1 = NULL;
+	g_autofree gchar *scheme2 = NULL;
+
+	scheme1 = gs_utils_get_url_scheme ("appstream://gimp.desktop");
+	g_assert_cmpstr (scheme1, ==, "appstream");
+	scheme2 = gs_utils_get_url_scheme ("appstream:gimp.desktop");
+	g_assert_cmpstr (scheme2, ==, "appstream");
+
+	path1 = gs_utils_get_url_path ("appstream://gimp.desktop");
+	g_assert_cmpstr (path1, ==, "gimp.desktop");
+	path2 = gs_utils_get_url_path ("appstream:gimp.desktop");
+	g_assert_cmpstr (path2, ==, "gimp.desktop");
+	path3 = gs_utils_get_url_path ("apt:/gimp");
+	g_assert_cmpstr (path3, ==, "gimp");
+}
+
+static void
+gs_utils_wilson_func (void)
+{
+	g_assert_cmpint ((gint64) gs_utils_get_wilson_rating (0, 0, 0, 0, 0), ==, -1);
+	g_assert_cmpint ((gint64) gs_utils_get_wilson_rating (0, 0, 0, 0, 400), ==, 100);
+	g_assert_cmpint ((gint64) gs_utils_get_wilson_rating (10, 0, 0, 0, 400), ==, 98);
+	g_assert_cmpint ((gint64) gs_utils_get_wilson_rating (0, 0, 0, 0, 1), ==, 76);
+	g_assert_cmpint ((gint64) gs_utils_get_wilson_rating (5, 4, 20, 100, 400), ==, 93);
+}
+
+static void
+gs_os_release_func (void)
+{
+	g_autofree gchar *fn = NULL;
+	g_autoptr(GError) error = NULL;
+	g_autoptr(GsOsRelease) os_release = NULL;
+
+	fn = gs_test_get_filename (TESTDATADIR, "tests/os-release");
+	g_assert (fn != NULL);
+	g_setenv ("GS_SELF_TEST_OS_RELEASE_FILENAME", fn, TRUE);
+
+	os_release = gs_os_release_new (&error);
+	g_assert_no_error (error);
+	g_assert (os_release != NULL);
+	g_assert_cmpstr (gs_os_release_get_id (os_release), ==, "fedora");
+	g_assert_cmpstr (gs_os_release_get_name (os_release), ==, "Fedora");
+	g_assert_cmpstr (gs_os_release_get_version (os_release), ==, "25 (Workstation Edition)");
+	g_assert_cmpstr (gs_os_release_get_version_id (os_release), ==, "25");
+	g_assert_cmpstr (gs_os_release_get_pretty_name (os_release), ==, "Fedora 25 (Workstation Edition)");
+}
+
+static void
+gs_utils_append_kv_func (void)
+{
+	g_autoptr(GString) str = g_string_new (NULL);
+
+	/* normal */
+	gs_utils_append_key_value (str, 5, "key", "val");
+	g_assert_cmpstr (str->str, ==, "key:  val\n");
+
+	/* oversize */
+	g_string_truncate (str, 0);
+	gs_utils_append_key_value (str, 5, "longkey", "val");
+	g_assert_cmpstr (str->str, ==, "longkey: val\n");
+
+	/* null key */
+	g_string_truncate (str, 0);
+	gs_utils_append_key_value (str, 5, NULL, "val");
+	g_assert_cmpstr (str->str, ==, "      val\n");
+
+	/* zero align key */
+	g_string_truncate (str, 0);
+	gs_utils_append_key_value (str, 0, "key", "val");
+	g_assert_cmpstr (str->str, ==, "key: val\n");
+}
+
+static void
+gs_utils_cache_func (void)
+{
+	g_autofree gchar *fn1 = NULL;
+	g_autofree gchar *fn2 = NULL;
+	g_autoptr(GError) error = NULL;
+
+	fn1 = gs_utils_get_cache_filename ("test",
+					   "http://www.foo.bar/baz",
+					   GS_UTILS_CACHE_FLAG_WRITEABLE |
+					   GS_UTILS_CACHE_FLAG_CREATE_DIRECTORY,
+					   &error);
+	g_assert_no_error (error);
+	g_assert_cmpstr (fn1, !=, NULL);
+	g_assert (g_str_has_prefix (fn1, g_get_user_cache_dir ()));
+	g_assert (g_str_has_suffix (fn1, "test/baz"));
+
+	fn2 = gs_utils_get_cache_filename ("test",
+					   "http://www.foo.bar/baz",
+					   GS_UTILS_CACHE_FLAG_WRITEABLE |
+					   GS_UTILS_CACHE_FLAG_USE_HASH |
+					   GS_UTILS_CACHE_FLAG_CREATE_DIRECTORY,
+					   &error);
+	g_assert_no_error (error);
+	g_assert_cmpstr (fn2, !=, NULL);
+	g_assert (g_str_has_prefix (fn2, g_get_user_cache_dir ()));
+	g_assert (g_str_has_suffix (fn2, "test/295099f59d12b3eb0b955325fcb699cd23792a89-baz"));
+}
+
+static void
+gs_utils_error_func (void)
+{
+	g_autofree gchar *app_id = NULL;
+	g_autofree gchar *origin_id = NULL;
+	g_autoptr(GError) error = NULL;
+	g_autoptr(GsApp) app = gs_app_new ("gimp.desktop");
+	g_autoptr(GsApp) origin = gs_app_new ("gimp-repo");
+
+	for (guint i = 0; i < GS_PLUGIN_ERROR_LAST; i++)
+		g_assert (gs_plugin_error_to_string (i) != NULL);
+
+	/* noop */
+	gs_utils_error_add_app_id (&error, app);
+	gs_utils_error_add_origin_id (&error, origin);
+
+	g_set_error (&error,
+		     GS_PLUGIN_ERROR,
+		     GS_PLUGIN_ERROR_DOWNLOAD_FAILED,
+		     "failed");
+	g_assert_cmpstr (error->message, ==, "failed");
+	gs_utils_error_add_app_id (&error, app);
+	gs_utils_error_add_origin_id (&error, origin);
+	g_assert_cmpstr (error->message, ==, "[*/*/*/gimp-repo/*] {*/*/*/gimp.desktop/*} failed");
+
+	/* find and strip any unique IDs from the error message */
+	for (guint i = 0; i < 2; i++) {
+		if (app_id == NULL)
+			app_id = gs_utils_error_strip_app_id (error);
+		if (origin_id == NULL)
+			origin_id = gs_utils_error_strip_origin_id (error);
+	}
+
+	g_assert_cmpstr (app_id, ==, "*/*/*/gimp.desktop/*");
+	g_assert_cmpstr (origin_id, ==, "*/*/*/gimp-repo/*");
+	g_assert_cmpstr (error->message, ==, "failed");
+}
+
+static void
+gs_plugin_download_rewrite_func (void)
+{
+	g_autofree gchar *css = NULL;
+	g_autoptr(GError) error = NULL;
+	g_autoptr(GDBusConnection) bus_connection = NULL;
+	g_autoptr(GsPlugin) plugin = NULL;
+	const gchar *resource = "background:\n"
+				" url('file://" DATADIR "/gnome-software/featured-maps.png')\n"
+				" url('file://" DATADIR "/gnome-software/featured-maps-bg.png')\n"
+				" bottom center / contain no-repeat;\n";
+
+	/* only when installed */
+	if (!g_file_test (DATADIR "/gnome-software/featured-maps.png", G_FILE_TEST_EXISTS)) {
+		g_test_skip ("not installed");
+		return;
+	}
+
+	/* test rewrite */
+	bus_connection = g_bus_get_sync (G_BUS_TYPE_SESSION, NULL, &error);
+	g_assert_no_error (error);
+
+	plugin = gs_plugin_new (bus_connection, bus_connection);
+	gs_plugin_set_name (plugin, "self-test");
+	css = gs_plugin_download_rewrite_resource (plugin,
+						   NULL, /* app */
+						   resource,
+						   NULL,
+						   &error);
+	g_assert_no_error (error);
+	g_assert (css != NULL);
+}
+
+static void
+gs_plugin_func (void)
+{
+	GsAppList *list;
+	GsAppList *list_dup;
+	GsAppList *list_remove;
+	GsApp *app;
+
+	/* check enums converted */
+	for (guint i = 0; i < GS_PLUGIN_ACTION_LAST; i++) {
+		const gchar *tmp = gs_plugin_action_to_string (i);
+		if (tmp == NULL)
+			g_critical ("failed to convert %u", i);
+		g_assert_cmpint (gs_plugin_action_from_string (tmp), ==, i);
+	}
+	for (guint i = 1; i < GS_PLUGIN_ACTION_LAST; i++) {
+		const gchar *tmp = gs_plugin_action_to_function_name (i);
+		if (tmp == NULL) {
+			/* These do not have function, they exist only for better error messages. */
+			if (i == GS_PLUGIN_ACTION_INSTALL_REPO ||
+			    i == GS_PLUGIN_ACTION_REMOVE_REPO ||
+			    i == GS_PLUGIN_ACTION_ENABLE_REPO ||
+			    i == GS_PLUGIN_ACTION_DISABLE_REPO)
+				continue;
+			g_critical ("failed to convert %u", i);
+		}
+	}
+
+	/* add a couple of duplicate IDs */
+	app = gs_app_new ("a");
+	list = gs_app_list_new ();
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+
+	/* test refcounting */
+	g_assert_cmpstr (gs_app_get_id (gs_app_list_index (list, 0)), ==, "a");
+	list_dup = gs_app_list_copy (list);
+	g_object_unref (list);
+	g_assert_cmpint (gs_app_list_length (list_dup), ==, 1);
+	g_assert_cmpstr (gs_app_get_id (gs_app_list_index (list_dup, 0)), ==, "a");
+	g_object_unref (list_dup);
+
+	/* test removing objects */
+	app = gs_app_new ("a");
+	list_remove = gs_app_list_new ();
+	gs_app_list_add (list_remove, app);
+	g_object_unref (app);
+	app = gs_app_new ("b");
+	gs_app_list_add (list_remove, app);
+	g_object_unref (app);
+	app = gs_app_new ("c");
+	gs_app_list_add (list_remove, app);
+	g_object_unref (app);
+	g_assert_cmpint (gs_app_list_length (list_remove), ==, 3);
+	gs_app_list_filter (list_remove, gs_app_list_filter_cb, NULL);
+	g_assert_cmpint (gs_app_list_length (list_remove), ==, 1);
+	g_assert_cmpstr (gs_app_get_id (gs_app_list_index (list_remove, 0)), ==, "b");
+
+	/* test removing duplicates at runtime */
+	app = gs_app_new ("b");
+	gs_app_list_add (list_remove, app);
+	g_object_unref (app);
+	app = gs_app_new ("b");
+	gs_app_list_add (list_remove, app);
+	g_object_unref (app);
+	g_assert_cmpint (gs_app_list_length (list_remove), ==, 1);
+	g_assert_cmpstr (gs_app_get_id (gs_app_list_index (list_remove, 0)), ==, "b");
+	g_object_unref (list_remove);
+
+	/* test removing duplicates when lazy-loading */
+	list_remove = gs_app_list_new ();
+	app = gs_app_new (NULL);
+	gs_app_list_add (list_remove, app);
+	gs_app_set_id (app, "e");
+	g_object_unref (app);
+	app = gs_app_new (NULL);
+	gs_app_list_add (list_remove, app);
+	gs_app_set_id (app, "e");
+	g_object_unref (app);
+	g_assert_cmpint (gs_app_list_length (list_remove), ==, 2);
+	gs_app_list_filter_duplicates (list_remove, GS_APP_LIST_FILTER_FLAG_NONE);
+	g_assert_cmpint (gs_app_list_length (list_remove), ==, 1);
+	g_object_unref (list_remove);
+
+	/* test removing duplicates when some apps have no app ID */
+	list_remove = gs_app_list_new ();
+	app = gs_app_new (NULL);
+	gs_app_list_add (list_remove, app);
+	g_object_unref (app);
+	app = gs_app_new (NULL);
+	gs_app_list_add (list_remove, app);
+	g_object_unref (app);
+	app = gs_app_new (NULL);
+	gs_app_list_add (list_remove, app);
+	gs_app_set_id (app, "e");
+	g_object_unref (app);
+	g_assert_cmpint (gs_app_list_length (list_remove), ==, 3);
+	gs_app_list_filter_duplicates (list_remove, GS_APP_LIST_FILTER_FLAG_NONE);
+	g_assert_cmpint (gs_app_list_length (list_remove), ==, 3);
+	g_object_unref (list_remove);
+
+	/* remove lazy-loaded app */
+	list_remove = gs_app_list_new ();
+	app = gs_app_new (NULL);
+	gs_app_list_add (list_remove, app);
+	gs_app_list_remove (list_remove, app);
+	g_assert_cmpint (gs_app_list_length (list_remove), ==, 0);
+	g_object_unref (app);
+	g_object_unref (list_remove);
+
+	/* respect priority when deduplicating */
+	list = gs_app_list_new ();
+	app = gs_app_new ("e");
+	gs_app_set_unique_id (app, "user/foo/*/e/*");
+	gs_app_list_add (list, app);
+	gs_app_set_priority (app, 0);
+	g_object_unref (app);
+	app = gs_app_new ("e");
+	gs_app_set_unique_id (app, "user/bar/*/e/*");
+	gs_app_list_add (list, app);
+	gs_app_set_priority (app, 99);
+	g_object_unref (app);
+	app = gs_app_new ("e");
+	gs_app_set_unique_id (app, "user/baz/*/e/*");
+	gs_app_list_add (list, app);
+	gs_app_set_priority (app, 50);
+	g_object_unref (app);
+	g_assert_cmpint (gs_app_list_length (list), ==, 3);
+	gs_app_list_filter_duplicates (list, GS_APP_LIST_FILTER_FLAG_KEY_ID);
+	g_assert_cmpint (gs_app_list_length (list), ==, 1);
+	g_assert_cmpstr (gs_app_get_unique_id (gs_app_list_index (list, 0)), ==, "user/bar/*/e/*");
+	g_object_unref (list);
+
+	/* respect priority (using name and version) when deduplicating */
+	list = gs_app_list_new ();
+	app = gs_app_new ("e");
+	gs_app_add_source (app, "foo");
+	gs_app_set_version (app, "1.2.3");
+	gs_app_set_unique_id (app, "user/foo/repo/*/*");
+	gs_app_list_add (list, app);
+	gs_app_set_priority (app, 0);
+	g_object_unref (app);
+	app = gs_app_new ("e");
+	gs_app_add_source (app, "foo");
+	gs_app_set_version (app, "1.2.3");
+	gs_app_set_unique_id (app, "user/foo/repo-security/*/*");
+	gs_app_list_add (list, app);
+	gs_app_set_priority (app, 99);
+	g_object_unref (app);
+	app = gs_app_new ("e");
+	gs_app_add_source (app, "foo");
+	gs_app_set_version (app, "1.2.3");
+	gs_app_set_unique_id (app, "user/foo/repo-universe/*/*");
+	gs_app_list_add (list, app);
+	gs_app_set_priority (app, 50);
+	g_object_unref (app);
+	g_assert_cmpint (gs_app_list_length (list), ==, 3);
+	gs_app_list_filter_duplicates (list, GS_APP_LIST_FILTER_FLAG_KEY_ID |
+					     GS_APP_LIST_FILTER_FLAG_KEY_SOURCE |
+					     GS_APP_LIST_FILTER_FLAG_KEY_VERSION);
+	g_assert_cmpint (gs_app_list_length (list), ==, 1);
+	g_assert_cmpstr (gs_app_get_unique_id (gs_app_list_index (list, 0)), ==, "user/foo/repo-security/*/*");
+	g_object_unref (list);
+
+	/* prefer installed applications */
+	list = gs_app_list_new ();
+	app = gs_app_new ("e");
+	gs_app_set_state (app, GS_APP_STATE_INSTALLED);
+	gs_app_set_unique_id (app, "user/foo/*/e/*");
+	gs_app_set_priority (app, 0);
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+	app = gs_app_new ("e");
+	gs_app_set_state (app, GS_APP_STATE_AVAILABLE);
+	gs_app_set_unique_id (app, "user/bar/*/e/*");
+	gs_app_set_priority (app, 100);
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+	gs_app_list_filter_duplicates (list,
+				       GS_APP_LIST_FILTER_FLAG_KEY_ID |
+				       GS_APP_LIST_FILTER_FLAG_PREFER_INSTALLED);
+	g_assert_cmpint (gs_app_list_length (list), ==, 1);
+	g_assert_cmpstr (gs_app_get_unique_id (gs_app_list_index (list, 0)), ==, "user/foo/*/e/*");
+	g_object_unref (list);
+
+	/* use the provides ID to dedupe */
+	list = gs_app_list_new ();
+	app = gs_app_new ("gimp.desktop");
+	gs_app_set_unique_id (app, "user/fedora/*/gimp.desktop/*");
+	gs_app_set_priority (app, 0);
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+	app = gs_app_new ("org.gimp.GIMP");
+	gs_app_add_provided_item (app,
+				  AS_PROVIDED_KIND_ID,
+				  "gimp.desktop");
+	gs_app_set_unique_id (app, "user/flathub/*/org.gimp.GIMP/*");
+	gs_app_set_priority (app, 100);
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+	gs_app_list_filter_duplicates (list, GS_APP_LIST_FILTER_FLAG_KEY_ID_PROVIDES);
+	g_assert_cmpint (gs_app_list_length (list), ==, 1);
+	g_assert_cmpstr (gs_app_get_unique_id (gs_app_list_index (list, 0)), ==,
+			 "user/flathub/*/org.gimp.GIMP/*");
+	g_object_unref (list);
+
+	/* use globs when adding */
+	list = gs_app_list_new ();
+	app = gs_app_new ("b");
+	gs_app_set_unique_id (app, "a/b/c/d/e");
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+	app = gs_app_new ("b");
+	gs_app_set_unique_id (app, "a/b/c/*/e");
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+	g_assert_cmpint (gs_app_list_length (list), ==, 1);
+	g_assert_cmpstr (gs_app_get_id (gs_app_list_index (list, 0)), ==, "b");
+	g_object_unref (list);
+
+	/* lookup with a wildcard */
+	list = gs_app_list_new ();
+	app = gs_app_new ("b");
+	gs_app_set_unique_id (app, "a/b/c/d/e");
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+	g_assert (gs_app_list_lookup (list, "a/b/c/d/e") != NULL);
+	g_assert (gs_app_list_lookup (list, "a/b/c/d/*") != NULL);
+	g_assert (gs_app_list_lookup (list, "*/b/c/d/e") != NULL);
+	g_assert (gs_app_list_lookup (list, "x/x/x/x/x") == NULL);
+	g_object_unref (list);
+
+	/* allow duplicating a wildcard */
+	list = gs_app_list_new ();
+	app = gs_app_new ("gimp.desktop");
+	gs_app_add_quirk (app, GS_APP_QUIRK_IS_WILDCARD);
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+	app = gs_app_new ("gimp.desktop");
+	gs_app_set_unique_id (app, "system/flatpak/*/gimp.desktop/stable");
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+	g_assert_cmpint (gs_app_list_length (list), ==, 2);
+	g_object_unref (list);
+
+	/* allow duplicating a wildcard */
+	list = gs_app_list_new ();
+	app = gs_app_new ("gimp.desktop");
+	gs_app_add_quirk (app, GS_APP_QUIRK_IS_WILDCARD);
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+	app = gs_app_new ("gimp.desktop");
+	gs_app_add_quirk (app, GS_APP_QUIRK_IS_WILDCARD);
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+	g_assert_cmpint (gs_app_list_length (list), ==, 1);
+	g_object_unref (list);
+
+	/* add a list to a list */
+	list = gs_app_list_new ();
+	list_dup = gs_app_list_new ();
+	app = gs_app_new ("a");
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+	app = gs_app_new ("b");
+	gs_app_list_add (list_dup, app);
+	g_object_unref (app);
+	gs_app_list_add_list (list, list_dup);
+	g_assert_cmpint (gs_app_list_length (list), ==, 2);
+	g_assert_cmpint (gs_app_list_length (list_dup), ==, 1);
+	g_object_unref (list);
+	g_object_unref (list_dup);
+
+	/* remove apps from the list */
+	list = gs_app_list_new ();
+	app = gs_app_new ("a");
+	gs_app_list_add (list, app);
+	gs_app_list_remove (list, app);
+	g_object_unref (app);
+	g_assert_cmpint (gs_app_list_length (list), ==, 0);
+	g_object_unref (list);
+
+	/* truncate list */
+	list = gs_app_list_new ();
+	app = gs_app_new ("a");
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+	app = gs_app_new ("b");
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+	app = gs_app_new ("c");
+	gs_app_list_add (list, app);
+	g_object_unref (app);
+	g_assert (!gs_app_list_has_flag (list, GS_APP_LIST_FLAG_IS_TRUNCATED));
+	g_assert_cmpint (gs_app_list_get_size_peak (list), ==, 3);
+	gs_app_list_truncate (list, 3);
+	g_assert_cmpint (gs_app_list_length (list), ==, 3);
+	g_assert (gs_app_list_has_flag (list, GS_APP_LIST_FLAG_IS_TRUNCATED));
+	g_assert_cmpint (gs_app_list_get_size_peak (list), ==, 3);
+	gs_app_list_truncate (list, 2);
+	g_assert_cmpint (gs_app_list_length (list), ==, 2);
+	gs_app_list_truncate (list, 1);
+	g_assert_cmpint (gs_app_list_length (list), ==, 1);
+	gs_app_list_truncate (list, 0);
+	g_assert_cmpint (gs_app_list_length (list), ==, 0);
+	g_assert_cmpint (gs_app_list_get_size_peak (list), ==, 3);
+	g_object_unref (list);
+}
+
+static gpointer
+gs_app_thread_cb (gpointer data)
+{
+	GsApp *app = GS_APP (data);
+	for (guint i = 0; i < 10000; i++) {
+		g_assert_cmpstr (gs_app_get_unique_id (app), !=, NULL);
+		gs_app_set_branch (app, "master");
+		g_assert_cmpstr (gs_app_get_unique_id (app), !=, NULL);
+		gs_app_set_branch (app, "stable");
+	}
+	return NULL;
+}
+
+static void
+gs_app_thread_func (gconstpointer user_data)
+{
+	GsDebug *debug = GS_DEBUG ((void *)user_data);
+	GThread *thread1;
+	GThread *thread2;
+	g_autoptr(GsApp) app = gs_app_new ("gimp.desktop");
+
+	/* try really hard to cause a threading problem */
+	gs_debug_set_verbose (debug, FALSE);
+	thread1 = g_thread_new ("thread1", gs_app_thread_cb, app);
+	thread2 = g_thread_new ("thread2", gs_app_thread_cb, app);
+	g_thread_join (thread1); /* consumes the reference  */
+	g_thread_join (thread2);
+	gs_debug_set_verbose (debug, TRUE);
+}
+
+static void
+gs_app_unique_id_func (void)
+{
+	g_autoptr(GsApp) app = gs_app_new (NULL);
+	g_autofree gchar *data_id = NULL;
+	const gchar *unique_id;
+
+	unique_id = "system/flatpak/gnome/org.gnome.Software/master";
+	gs_app_set_from_unique_id (app, unique_id, AS_COMPONENT_KIND_DESKTOP_APP);
+	g_assert (GS_IS_APP (app));
+	g_assert_cmpint (gs_app_get_scope (app), ==, AS_COMPONENT_SCOPE_SYSTEM);
+	g_assert_cmpint (gs_app_get_bundle_kind (app), ==, AS_BUNDLE_KIND_FLATPAK);
+	g_assert_cmpstr (gs_app_get_origin (app), ==, "gnome");
+	g_assert_cmpint (gs_app_get_kind (app), ==, AS_COMPONENT_KIND_DESKTOP_APP);
+	g_assert_cmpstr (gs_app_get_id (app), ==, "org.gnome.Software");
+	g_assert_cmpstr (gs_app_get_branch (app), ==, "master");
+
+	/* test conversions from 6-part IDs */
+	data_id = gs_utils_unique_id_compat_convert (unique_id);
+	g_assert_cmpstr (data_id, ==, unique_id);
+	g_clear_pointer (&data_id, g_free);
+
+	data_id = gs_utils_unique_id_compat_convert ("not a unique ID");
+	g_assert_null (data_id);
+
+	data_id = gs_utils_unique_id_compat_convert ("system/flatpak/gnome/desktop-app/org.gnome.Software/master");
+	g_assert_cmpstr (data_id, ==, unique_id);
+	g_clear_pointer (&data_id, g_free);
+}
+
+static void
+gs_app_addons_func (void)
+{
+	g_autoptr(GsApp) app = gs_app_new ("test.desktop");
+	g_autoptr(GsApp) addon = NULL;
+	g_autoptr(GsAppList) addons_list = NULL;
+
+	/* create, add then drop ref, so @app has the only refcount of addon */
+	addon = gs_app_new ("test.desktop");
+	addons_list = gs_app_list_new ();
+	gs_app_list_add (addons_list, addon);
+
+	gs_app_add_addons (app, addons_list);
+
+	gs_app_remove_addon (app, addon);
+}
+
+static void
+gs_app_func (void)
+{
+	g_autoptr(GsApp) app = NULL;
+
+	app = gs_app_new ("gnome-software.desktop");
+	g_assert (GS_IS_APP (app));
+	g_assert_cmpstr (gs_app_get_id (app), ==, "gnome-software.desktop");
+
+	/* check we clean up the version, but not at the expense of having
+	 * the same string as the update version */
+	gs_app_set_version (app, "2.8.6-3.fc20");
+	gs_app_set_update_version (app, "2.8.6-4.fc20");
+	g_assert_cmpstr (gs_app_get_version (app), ==, "2.8.6-3.fc20");
+	g_assert_cmpstr (gs_app_get_update_version (app), ==, "2.8.6-4.fc20");
+	g_assert_cmpstr (gs_app_get_version_ui (app), ==, "2.8.6-3");
+	g_assert_cmpstr (gs_app_get_update_version_ui (app), ==, "2.8.6-4");
+
+	/* check the quality stuff works */
+	gs_app_set_name (app, GS_APP_QUALITY_NORMAL, "dave");
+	g_assert_cmpstr (gs_app_get_name (app), ==, "dave");
+	gs_app_set_name (app, GS_APP_QUALITY_LOWEST, "brian");
+	g_assert_cmpstr (gs_app_get_name (app), ==, "dave");
+	gs_app_set_name (app, GS_APP_QUALITY_HIGHEST, "hugh");
+	g_assert_cmpstr (gs_app_get_name (app), ==, "hugh");
+
+	/* check non-transient state saving */
+	gs_app_set_state (app, GS_APP_STATE_INSTALLED);
+	g_assert_cmpint (gs_app_get_state (app), ==, GS_APP_STATE_INSTALLED);
+	gs_app_set_state (app, GS_APP_STATE_REMOVING);
+	g_assert_cmpint (gs_app_get_state (app), ==, GS_APP_STATE_REMOVING);
+	gs_app_set_state_recover (app); // simulate an error
+	g_assert_cmpint (gs_app_get_state (app), ==, GS_APP_STATE_INSTALLED);
+
+	/* try again */
+	gs_app_set_state (app, GS_APP_STATE_REMOVING);
+	g_assert_cmpint (gs_app_get_state (app), ==, GS_APP_STATE_REMOVING);
+	gs_app_set_state_recover (app); // simulate an error
+	g_assert_cmpint (gs_app_get_state (app), ==, GS_APP_STATE_INSTALLED);
+
+	/* correctly parse URL */
+	gs_app_set_origin_hostname (app, "https://mirrors.fedoraproject.org/metalink");
+	g_assert_cmpstr (gs_app_get_origin_hostname (app), ==, "fedoraproject.org");
+	gs_app_set_origin_hostname (app, "file:///home/hughsie");
+	g_assert_cmpstr (gs_app_get_origin_hostname (app), ==, "localhost");
+
+	/* check setting the progress */
+	gs_app_set_progress (app, 42);
+	g_assert_cmpuint (gs_app_get_progress (app), ==, 42);
+	gs_app_set_progress (app, 0);
+	g_assert_cmpuint (gs_app_get_progress (app), ==, 0);
+	gs_app_set_progress (app, GS_APP_PROGRESS_UNKNOWN);
+	g_assert_cmpuint (gs_app_get_progress (app), ==, GS_APP_PROGRESS_UNKNOWN);
+	g_assert_false ((gint) 0 <= (gint) GS_APP_PROGRESS_UNKNOWN && GS_APP_PROGRESS_UNKNOWN <= 100);
+
+	/* check pending action */
+	g_assert_cmpuint (gs_app_get_pending_action (app), ==, GS_PLUGIN_ACTION_UNKNOWN);
+	gs_app_set_state (app, GS_APP_STATE_UPDATABLE_LIVE);
+	gs_app_set_pending_action (app, GS_PLUGIN_ACTION_UPDATE);
+	g_assert_cmpuint (gs_app_get_pending_action (app), ==, GS_PLUGIN_ACTION_UPDATE);
+	gs_app_set_state (app, GS_APP_STATE_INSTALLING);
+	g_assert_cmpuint (gs_app_get_pending_action (app), ==, GS_PLUGIN_ACTION_UNKNOWN);
+	gs_app_set_state_recover (app);
+}
+
+static void
+gs_app_progress_clamping_func (void)
+{
+	g_autoptr(GsApp) app = NULL;
+
+	if (g_test_subprocess ()) {
+		app = gs_app_new ("gnome-software.desktop");
+		gs_app_set_progress (app, 142);
+		g_assert_cmpuint (gs_app_get_progress (app), ==, 100);
+	} else {
+		g_test_trap_subprocess (NULL, 0, 0);
+		g_test_trap_assert_failed ();
+		g_test_trap_assert_stderr ("*cannot set 142% for *, setting instead: 100%*");
+	}
+}
+
+static void
+gs_app_list_wildcard_dedupe_func (void)
+{
+	g_autoptr(GsAppList) list = gs_app_list_new ();
+	g_autoptr(GsApp) app1 = gs_app_new ("app");
+	g_autoptr(GsApp) app2 = gs_app_new ("app");
+
+	gs_app_add_quirk (app1, GS_APP_QUIRK_IS_WILDCARD);
+	gs_app_list_add (list, app1);
+	gs_app_add_quirk (app2, GS_APP_QUIRK_IS_WILDCARD);
+	gs_app_list_add (list, app2);
+	g_assert_cmpint (gs_app_list_length (list), ==, 1);
+}
+
+static void
+gs_app_list_func (void)
+{
+	g_autoptr(GsAppList) list = gs_app_list_new ();
+	g_autoptr(GsApp) app1 = gs_app_new ("app1");
+	g_autoptr(GsApp) app2 = gs_app_new ("app2");
+
+	/* turn on */
+	gs_app_list_add_flag (list, GS_APP_LIST_FLAG_WATCH_APPS);
+
+	g_assert_cmpint (gs_app_list_get_progress (list), ==, 0);
+	g_assert_cmpint (gs_app_list_get_state (list), ==, GS_APP_STATE_UNKNOWN);
+	gs_app_list_add (list, app1);
+	gs_app_set_progress (app1, 75);
+	gs_app_set_state (app1, GS_APP_STATE_AVAILABLE);
+	gs_app_set_state (app1, GS_APP_STATE_INSTALLING);
+	gs_test_flush_main_context ();
+	g_assert_cmpint (gs_app_list_get_progress (list), ==, 75);
+	g_assert_cmpint (gs_app_list_get_state (list), ==, GS_APP_STATE_INSTALLING);
+
+	gs_app_list_add (list, app2);
+	gs_app_set_progress (app2, 25);
+	gs_test_flush_main_context ();
+	g_assert_cmpint (gs_app_list_get_progress (list), ==, 50);
+	g_assert_cmpint (gs_app_list_get_state (list), ==, GS_APP_STATE_INSTALLING);
+
+	gs_app_list_remove (list, app1);
+	g_assert_cmpint (gs_app_list_get_progress (list), ==, 25);
+	g_assert_cmpint (gs_app_list_get_state (list), ==, GS_APP_STATE_UNKNOWN);
+}
+
+static void
+gs_app_list_performance_func (void)
+{
+	g_autoptr(GPtrArray) apps = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);
+	g_autoptr(GsAppList) list = gs_app_list_new ();
+	g_autoptr(GTimer) timer = NULL;
+
+	/* create a few apps */
+	for (guint i = 0; i < 500; i++) {
+		g_autofree gchar *id = g_strdup_printf ("%03u.desktop", i);
+		g_ptr_array_add (apps, gs_app_new (id));
+	}
+
+	/* add them to the list */
+	timer = g_timer_new ();
+	for (guint i = 0; i < apps->len; i++) {
+		GsApp *app = g_ptr_array_index (apps, i);
+		gs_app_list_add (list, app);
+	}
+	g_print ("%.2fms ", g_timer_elapsed (timer, NULL) * 1000);
+}
+
+static void
+gs_app_list_related_func (void)
+{
+	g_autoptr(GsAppList) list = gs_app_list_new ();
+	g_autoptr(GsApp) app = gs_app_new ("app");
+	g_autoptr(GsApp) related = gs_app_new ("related");
+
+	/* turn on */
+	gs_app_list_add_flag (list,
+			      GS_APP_LIST_FLAG_WATCH_APPS |
+			      GS_APP_LIST_FLAG_WATCH_APPS_RELATED);
+	gs_app_add_related (app, related);
+	gs_app_list_add (list, app);
+
+	gs_app_set_progress (app, 75);
+	gs_app_set_progress (related, 25);
+	gs_test_flush_main_context ();
+	g_assert_cmpint (gs_app_list_get_progress (list), ==, 50);
+}
+
+int
+main (int argc, char **argv)
+{
+	g_autoptr(GsDebug) debug = gs_debug_new (NULL, TRUE, FALSE);
+
+	gs_test_init (&argc, &argv);
+
+	/* tests go here */
+	g_test_add_func ("/gnome-software/lib/utils{url}", gs_utils_url_func);
+	g_test_add_func ("/gnome-software/lib/utils{wilson}", gs_utils_wilson_func);
+	g_test_add_func ("/gnome-software/lib/utils{error}", gs_utils_error_func);
+	g_test_add_func ("/gnome-software/lib/utils{cache}", gs_utils_cache_func);
+	g_test_add_func ("/gnome-software/lib/utils{append-kv}", gs_utils_append_kv_func);
+	g_test_add_func ("/gnome-software/lib/os-release", gs_os_release_func);
+	g_test_add_func ("/gnome-software/lib/app", gs_app_func);
+	g_test_add_func ("/gnome-software/lib/app/progress-clamping", gs_app_progress_clamping_func);
+	g_test_add_func ("/gnome-software/lib/app{addons}", gs_app_addons_func);
+	g_test_add_func ("/gnome-software/lib/app{unique-id}", gs_app_unique_id_func);
+	g_test_add_data_func ("/gnome-software/lib/app{thread}", debug, gs_app_thread_func);
+	g_test_add_func ("/gnome-software/lib/app{list}", gs_app_list_func);
+	g_test_add_func ("/gnome-software/lib/app{list-wildcard-dedupe}", gs_app_list_wildcard_dedupe_func);
+	g_test_add_func ("/gnome-software/lib/app{list-performance}", gs_app_list_performance_func);
+	g_test_add_func ("/gnome-software/lib/app{list-related}", gs_app_list_related_func);
+	g_test_add_func ("/gnome-software/lib/plugin", gs_plugin_func);
+	g_test_add_func ("/gnome-software/lib/plugin{download-rewrite}", gs_plugin_download_rewrite_func);
+
+	return g_test_run ();
+}
diff --git a/lib/gs-test.c b/lib/gs-test.c
new file mode 100644
index 0000000..2a2e107
--- /dev/null
+++ b/lib/gs-test.c
@@ -0,0 +1,147 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2013-2016 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <stdlib.h>
+
+#include "gs-plugin-loader-sync.h"
+#include "gs-test.h"
+
+/**
+ * gs_test_init:
+ *
+ * Initializes the environment with the common settings for the test,
+ * as a replacement for the g_test_init(), which is called as well.
+ *
+ * Since: 42
+ **/
+void
+gs_test_init (gint *pargc,
+	      gchar ***pargv)
+{
+	g_autoptr(GSettings) settings = NULL;
+
+	g_setenv ("GSETTINGS_BACKEND", "memory", FALSE);
+	g_setenv ("G_MESSAGES_DEBUG", "all", TRUE);
+
+	/* To not download ODRS data during the test */
+	settings = g_settings_new ("org.gnome.software");
+	g_settings_set_string (settings, "review-server", "");
+
+	g_test_init (pargc, pargv,
+		     G_TEST_OPTION_ISOLATE_DIRS,
+		     NULL);
+
+	/* only critical and error are fatal */
+	g_log_set_fatal_mask (NULL, G_LOG_LEVEL_ERROR | G_LOG_LEVEL_CRITICAL);
+}
+
+gchar *
+gs_test_get_filename (const gchar *testdatadir, const gchar *filename)
+{
+	gchar *tmp;
+	char full_tmp[PATH_MAX];
+	g_autofree gchar *path = NULL;
+	path = g_build_filename (testdatadir, filename, NULL);
+	g_debug ("looking in %s", path);
+	tmp = realpath (path, full_tmp);
+	if (tmp == NULL)
+		return NULL;
+	return g_strdup (full_tmp);
+}
+
+void
+gs_test_flush_main_context (void)
+{
+	guint cnt = 0;
+	while (g_main_context_iteration (NULL, FALSE)) {
+		if (cnt == 0)
+			g_debug ("clearing pending events...");
+		cnt++;
+	}
+	if (cnt > 0)
+		g_debug ("cleared %u events", cnt);
+}
+
+/**
+ * gs_test_expose_icon_theme_paths:
+ *
+ * Calculate and set the `GS_SELF_TEST_ICON_THEME_PATH` environment variable
+ * to include the current system icon theme paths. This is designed to be called
+ * before calling `gs_test_init()`, which will clear the system icon theme paths.
+ *
+ * As this function calls `g_setenv()`, it must not be called after threads have
+ * been spawned.
+ *
+ * Calling this function is an explicit acknowledgement that the code under test
+ * should be accessing the icon theme.
+ *
+ * Since: 3.38
+ */
+void
+gs_test_expose_icon_theme_paths (void)
+{
+	const gchar * const *data_dirs;
+	g_autoptr(GString) data_dirs_str = NULL;
+	g_autofree gchar *data_dirs_joined = NULL;
+
+	data_dirs = g_get_system_data_dirs ();
+	data_dirs_str = g_string_new ("");
+	for (gsize i = 0; data_dirs[i] != NULL; i++)
+		g_string_append_printf (data_dirs_str, "%s%s/icons",
+					(data_dirs_str->len > 0) ? ":" : "",
+					data_dirs[i]);
+	data_dirs_joined = g_string_free (g_steal_pointer (&data_dirs_str), FALSE);
+	g_setenv ("GS_SELF_TEST_ICON_THEME_PATH", data_dirs_joined, TRUE);
+}
+
+/**
+ * gs_test_reinitialise_plugin_loader:
+ * @plugin_loader: a #GsPluginLoader
+ *
+ * Calls setup on each plugin. This should only be used from the self tests
+ * and in a controlled way.
+ *
+ * Since: 42
+ */
+void
+gs_test_reinitialise_plugin_loader (GsPluginLoader      *plugin_loader,
+                                    const gchar * const *allowlist,
+                                    const gchar * const *blocklist)
+{
+	g_autoptr(GError) local_error = NULL;
+#ifdef HAVE_SYSPROF
+	gint64 begin_time_nsec G_GNUC_UNUSED = SYSPROF_CAPTURE_CURRENT_TIME;
+#endif
+
+	/* Shut down */
+	gs_plugin_loader_shutdown (plugin_loader, NULL);
+
+	/* clear global cache */
+	gs_plugin_loader_clear_caches (plugin_loader);
+
+	/* remove any events */
+	gs_plugin_loader_remove_events (plugin_loader);
+
+	/* Start all the plugins setting up again in parallel. Use the blocking
+	 * sync version of the function, just for the tests. */
+	gs_plugin_loader_setup (plugin_loader, allowlist, blocklist, NULL, &local_error);
+	g_assert_no_error (local_error);
+
+#ifdef HAVE_SYSPROF
+	if (plugin_loader->sysprof_writer != NULL) {
+		sysprof_capture_writer_add_mark (plugin_loader->sysprof_writer,
+						 begin_time_nsec,
+						 sched_getcpu (),
+						 getpid (),
+						 SYSPROF_CAPTURE_CURRENT_TIME - begin_time_nsec,
+						 "gnome-software",
+						 "setup-again",
+						 NULL);
+	}
+#endif  /* HAVE_SYSPROF */
+}
diff --git a/lib/gs-test.h b/lib/gs-test.h
new file mode 100644
index 0000000..8114c23
--- /dev/null
+++ b/lib/gs-test.h
@@ -0,0 +1,27 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2013-2016 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include "gs-app.h"
+#include "gs-plugin-loader.h"
+
+G_BEGIN_DECLS
+
+void	 gs_test_init				(gint		*pargc,
+						 gchar        ***pargv);
+void	 gs_test_flush_main_context		(void);
+gchar	*gs_test_get_filename			(const gchar	*testdatadir,
+						 const gchar	*filename);
+void	 gs_test_expose_icon_theme_paths	(void);
+
+void	 gs_test_reinitialise_plugin_loader	(GsPluginLoader		*plugin_loader,
+						 const gchar * const	*allowlist,
+						 const gchar * const	*blocklist);
+
+G_END_DECLS
diff --git a/lib/gs-utils.c b/lib/gs-utils.c
new file mode 100644
index 0000000..2c3fb5b
--- /dev/null
+++ b/lib/gs-utils.c
@@ -0,0 +1,1689 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2013-2017 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2015-2018 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-utils
+ * @title: GsUtils
+ * @include: gnome-software.h
+ * @stability: Unstable
+ * @short_description: Utilities that plugins can use
+ *
+ * These functions provide useful functionality that makes it easy to
+ * add new plugin functions.
+ */
+
+#include "config.h"
+
+#include <errno.h>
+#include <fnmatch.h>
+#include <math.h>
+#include <string.h>
+#include <glib/gstdio.h>
+#include <json-glib/json-glib.h>
+
+#if defined(__linux__)
+#include <sys/sysinfo.h>
+#elif defined(__FreeBSD__)
+#include <sys/types.h>
+#include <sys/sysctl.h>
+#endif
+
+#ifdef HAVE_POLKIT
+#include <polkit/polkit.h>
+#endif
+
+#include "gs-app.h"
+#include "gs-app-private.h"
+#include "gs-utils.h"
+#include "gs-plugin.h"
+
+#define MB_IN_BYTES (1024 * 1024)
+
+/**
+ * gs_mkdir_parent:
+ * @path: A full pathname
+ * @error: A #GError, or %NULL
+ *
+ * Creates any required directories, including any parent directories.
+ *
+ * Returns: %TRUE for success
+ **/
+gboolean
+gs_mkdir_parent (const gchar *path, GError **error)
+{
+	g_autofree gchar *parent = NULL;
+
+	parent = g_path_get_dirname (path);
+	if (g_mkdir_with_parents (parent, 0755) == -1) {
+		g_set_error (error,
+			     GS_PLUGIN_ERROR,
+			     GS_PLUGIN_ERROR_FAILED,
+			     "Failed to create '%s': %s",
+			     parent, g_strerror (errno));
+		return FALSE;
+	}
+	return TRUE;
+}
+
+/**
+ * gs_utils_get_file_age:
+ * @file: A #GFile
+ *
+ * Gets a file age.
+ *
+ * Returns: The time in seconds since the file was modified, or %G_MAXUINT64 for error
+ */
+guint64
+gs_utils_get_file_age (GFile *file)
+{
+	guint64 now;
+	guint64 mtime;
+	g_autoptr(GFileInfo) info = NULL;
+
+	info = g_file_query_info (file,
+				  G_FILE_ATTRIBUTE_TIME_MODIFIED,
+				  G_FILE_QUERY_INFO_NONE,
+				  NULL,
+				  NULL);
+	if (info == NULL)
+		return G_MAXUINT64;
+	mtime = g_file_info_get_attribute_uint64 (info, G_FILE_ATTRIBUTE_TIME_MODIFIED);
+	now = (guint64) g_get_real_time () / G_USEC_PER_SEC;
+	if (mtime > now)
+		return G_MAXUINT64;
+	if (now - mtime > G_MAXUINT64)
+		return G_MAXUINT64;
+	return (guint) (now - mtime);
+}
+
+static gchar *
+gs_utils_filename_array_return_newest (GPtrArray *array)
+{
+	const gchar *filename_best = NULL;
+	guint age_lowest = G_MAXUINT;
+	guint i;
+	for (i = 0; i < array->len; i++) {
+		const gchar *fn = g_ptr_array_index (array, i);
+		g_autoptr(GFile) file = g_file_new_for_path (fn);
+		guint64 age_tmp = gs_utils_get_file_age (file);
+		if (age_tmp < age_lowest) {
+			age_lowest = age_tmp;
+			filename_best = fn;
+		}
+	}
+	return g_strdup (filename_best);
+}
+
+/**
+ * gs_utils_get_cache_filename:
+ * @kind: A cache kind, e.g. "fwupd" or "screenshots/123x456"
+ * @resource: A resource, e.g. "system.bin" or "http://foo.bar/baz.bin"
+ * @flags: Some #GsUtilsCacheFlags, e.g. %GS_UTILS_CACHE_FLAG_WRITEABLE
+ * @error: A #GError, or %NULL
+ *
+ * Returns a filename that points into the cache.
+ * This may be per-system or per-user, the latter being more likely
+ * when %GS_UTILS_CACHE_FLAG_WRITEABLE is specified in @flags.
+ *
+ * If %GS_UTILS_CACHE_FLAG_USE_HASH is set in @flags then the returned filename
+ * will contain the hashed version of @resource.
+ *
+ * If there is more than one match, the file that has been modified last is
+ * returned.
+ *
+ * If a plugin requests a file to be saved in the cache it is the plugins
+ * responsibility to remove the file when it is no longer valid or is too old
+ * -- gnome-software will not ever clean the cache for the plugin.
+ * For this reason it is a good idea to use the plugin name as @kind.
+ *
+ * This function can only fail if %GS_UTILS_CACHE_FLAG_ENSURE_EMPTY or
+ * %GS_UTILS_CACHE_FLAG_CREATE_DIRECTORY are passed in @flags.
+ *
+ * Returns: The full path and filename, which may or may not exist, or %NULL
+ **/
+gchar *
+gs_utils_get_cache_filename (const gchar *kind,
+			     const gchar *resource,
+			     GsUtilsCacheFlags flags,
+			     GError **error)
+{
+	const gchar *tmp;
+	g_autofree gchar *basename = NULL;
+	g_autofree gchar *cachedir = NULL;
+	g_autoptr(GFile) cachedir_file = NULL;
+	g_autoptr(GPtrArray) candidates = g_ptr_array_new_with_free_func (g_free);
+	g_autoptr(GError) local_error = NULL;
+
+	/* in the self tests */
+	tmp = g_getenv ("GS_SELF_TEST_CACHEDIR");
+	if (tmp != NULL) {
+		cachedir = g_build_filename (tmp, kind, NULL);
+		cachedir_file = g_file_new_for_path (cachedir);
+
+		if ((flags & GS_UTILS_CACHE_FLAG_CREATE_DIRECTORY) &&
+		    !g_file_make_directory_with_parents (cachedir_file, NULL, &local_error) &&
+		    !g_error_matches (local_error, G_IO_ERROR, G_IO_ERROR_EXISTS)) {
+			g_propagate_error (error, g_steal_pointer (&local_error));
+			return NULL;
+		}
+
+		return g_build_filename (cachedir, resource, NULL);;
+	}
+
+	/* get basename */
+	if (flags & GS_UTILS_CACHE_FLAG_USE_HASH) {
+		g_autofree gchar *basename_tmp = g_path_get_basename (resource);
+		g_autofree gchar *hash = g_compute_checksum_for_string (G_CHECKSUM_SHA1,
+									resource, -1);
+		basename = g_strdup_printf ("%s-%s", hash, basename_tmp);
+	} else {
+		basename = g_path_get_basename (resource);
+	}
+
+	/* not writable, so try the system cache first */
+	if (!(flags & GS_UTILS_CACHE_FLAG_WRITEABLE)) {
+		g_autofree gchar *cachefn = NULL;
+		cachefn = g_build_filename (LOCALSTATEDIR,
+					    "cache",
+					    "gnome-software",
+		                            kind,
+					    basename,
+					    NULL);
+		if (g_file_test (cachefn, G_FILE_TEST_EXISTS)) {
+			g_ptr_array_add (candidates,
+					 g_steal_pointer (&cachefn));
+		}
+	}
+
+	/* create the cachedir in a per-release location, creating
+	 * if it does not already exist */
+	cachedir = g_build_filename (g_get_user_cache_dir (),
+				     "gnome-software",
+				     kind,
+				     NULL);
+	cachedir_file = g_file_new_for_path (cachedir);
+	if (g_file_query_exists (cachedir_file, NULL) &&
+	    flags & GS_UTILS_CACHE_FLAG_ENSURE_EMPTY) {
+		if (!gs_utils_rmtree (cachedir, error))
+			return NULL;
+	}
+	if ((flags & GS_UTILS_CACHE_FLAG_CREATE_DIRECTORY) &&
+	    !g_file_query_exists (cachedir_file, NULL) &&
+	    !g_file_make_directory_with_parents (cachedir_file, NULL, error))
+		return NULL;
+	g_ptr_array_add (candidates, g_build_filename (cachedir, basename, NULL));
+
+	/* common case: we only have one option */
+	if (candidates->len == 1)
+		return g_strdup (g_ptr_array_index (candidates, 0));
+
+	/* return the newest (i.e. one with least age) */
+	return gs_utils_filename_array_return_newest (candidates);
+}
+
+/**
+ * gs_utils_get_user_hash:
+ * @error: A #GError, or %NULL
+ *
+ * This SHA1 hash is composed of the contents of machine-id and your
+ * username and is also salted with a hardcoded value.
+ *
+ * This provides an identifier that can be used to identify a specific
+ * user on a machine, allowing them to cast only one vote or perform
+ * one review on each application.
+ *
+ * There is no known way to calculate the machine ID or username from
+ * the machine hash and there should be no privacy issue.
+ *
+ * Returns: The user hash, or %NULL on error
+ */
+gchar *
+gs_utils_get_user_hash (GError **error)
+{
+	g_autofree gchar *data = NULL;
+	g_autofree gchar *salted = NULL;
+
+	if (!g_file_get_contents ("/etc/machine-id", &data, NULL, error))
+		return NULL;
+
+	salted = g_strdup_printf ("gnome-software[%s:%s]",
+				  g_get_user_name (), data);
+	return g_compute_checksum_for_string (G_CHECKSUM_SHA1, salted, -1);
+}
+
+/**
+ * gs_utils_get_permission:
+ * @id: A PolicyKit ID, e.g. "org.gnome.Desktop"
+ * @cancellable: A #GCancellable, or %NULL
+ * @error: A #GError, or %NULL
+ *
+ * Gets a permission object for an ID.
+ *
+ * Returns: a #GPermission, or %NULL if this if not possible.
+ **/
+GPermission *
+gs_utils_get_permission (const gchar *id, GCancellable *cancellable, GError **error)
+{
+#ifdef HAVE_POLKIT
+	g_autoptr(GPermission) permission = NULL;
+	permission = polkit_permission_new_sync (id, NULL, cancellable, error);
+	if (permission == NULL) {
+		g_prefix_error (error, "failed to create permission %s: ", id);
+		gs_utils_error_convert_gio (error);
+		return NULL;
+	}
+	return g_steal_pointer (&permission);
+#else
+	g_set_error (error,
+		     GS_PLUGIN_ERROR,
+		     GS_PLUGIN_ERROR_NOT_SUPPORTED,
+		     "no PolicyKit, so can't return GPermission for %s", id);
+	return NULL;
+#endif
+}
+
+/**
+ * gs_utils_get_permission_async:
+ * @id: a polkit action ID, for example `org.freedesktop.packagekit.trigger-offline-update`
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @callback: callback for when the asynchronous operation is complete
+ * @user_data: data to pass to @callback
+ *
+ * Asynchronously gets a #GPermission object representing the given polkit
+ * action @id.
+ *
+ * Since: 42
+ */
+void
+gs_utils_get_permission_async (const gchar         *id,
+                               GCancellable        *cancellable,
+                               GAsyncReadyCallback  callback,
+                               gpointer             user_data)
+{
+	g_return_if_fail (id != NULL);
+	g_return_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable));
+
+#ifdef HAVE_POLKIT
+	polkit_permission_new (id, NULL, cancellable, callback, user_data);
+#else
+	g_task_report_new_error (NULL, callback, user_data, gs_utils_get_permission_async,
+				 GS_PLUGIN_ERROR,
+				 GS_PLUGIN_ERROR_NOT_SUPPORTED,
+				 "no PolicyKit, so can't return GPermission for %s", id);
+#endif
+}
+
+/**
+ * gs_utils_get_permission_finish:
+ * @result: result of the asynchronous operation
+ * @error: return location for a #GError, or %NULL
+ *
+ * Finish an asynchronous operation started with gs_utils_get_permission_async().
+ *
+ * Returns: (transfer full): a #GPermission representing the given action ID
+ * Since: 42
+ */
+GPermission *
+gs_utils_get_permission_finish (GAsyncResult  *result,
+                                GError       **error)
+{
+	g_return_val_if_fail (G_IS_ASYNC_RESULT (result), NULL);
+	g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+
+#ifdef HAVE_POLKIT
+	return polkit_permission_new_finish (result, error);
+#else
+	return g_task_propagate_pointer (G_TASK (result), error);
+#endif
+}
+
+/**
+ * gs_utils_get_content_type:
+ * @file: A GFile
+ * @cancellable: A #GCancellable, or %NULL
+ * @error: A #GError, or %NULL
+ *
+ * Gets the standard content type for a file.
+ *
+ * Returns: the content type, or %NULL, e.g. "text/plain"
+ */
+gchar *
+gs_utils_get_content_type (GFile *file,
+			   GCancellable *cancellable,
+			   GError **error)
+{
+	const gchar *tmp;
+	g_autoptr(GFileInfo) info = NULL;
+
+	/* get content type */
+	info = g_file_query_info (file,
+				  G_FILE_ATTRIBUTE_STANDARD_CONTENT_TYPE,
+				  G_FILE_QUERY_INFO_NONE,
+				  cancellable,
+				  error);
+	if (info == NULL)
+		return NULL;
+	tmp = g_file_info_get_attribute_string (info, G_FILE_ATTRIBUTE_STANDARD_CONTENT_TYPE);
+	if (tmp == NULL)
+		return NULL;
+	return g_strdup (tmp);
+}
+
+/**
+ * gs_utils_strv_fnmatch:
+ * @strv: A NUL-terminated list of strings
+ * @str: A string
+ *
+ * Matches a string against a list of globs.
+ *
+ * Returns: %TRUE if the list matches
+ */
+gboolean
+gs_utils_strv_fnmatch (gchar **strv, const gchar *str)
+{
+	guint i;
+
+	/* empty */
+	if (strv == NULL)
+		return FALSE;
+
+	/* look at each one */
+	for (i = 0; strv[i] != NULL; i++) {
+		if (fnmatch (strv[i], str, 0) == 0)
+			return TRUE;
+	}
+	return FALSE;
+}
+
+/**
+ * gs_utils_sort_key:
+ * @str: A string to convert to a sort key
+ *
+ * Useful to sort strings in a locale-sensitive, presentational way.
+ * Case is ignored and utf8 collation is used (e.g. accents are ignored).
+ *
+ * Returns: a newly allocated string sort key
+ */
+gchar *
+gs_utils_sort_key (const gchar *str)
+{
+	g_autofree gchar *casefolded = g_utf8_casefold (str, -1);
+	return g_utf8_collate_key (casefolded, -1);
+}
+
+/**
+ * gs_utils_sort_strcmp:
+ * @str1: (nullable): A string to compare
+ * @str2: (nullable): A string to compare
+ *
+ * Compares two strings in a locale-sensitive, presentational way.
+ * Case is ignored and utf8 collation is used (e.g. accents are ignored). %NULL
+ * is sorted before all non-%NULL strings, and %NULLs compare equal.
+ *
+ * Returns: < 0 if str1 is before str2, 0 if equal, > 0 if str1 is after str2
+ */
+gint
+gs_utils_sort_strcmp (const gchar *str1, const gchar *str2)
+{
+	g_autofree gchar *key1 = (str1 != NULL) ? gs_utils_sort_key (str1) : NULL;
+	g_autofree gchar *key2 = (str2 != NULL) ? gs_utils_sort_key (str2) : NULL;
+	return g_strcmp0 (key1, key2);
+}
+
+/**
+ * gs_utils_get_desktop_app_info:
+ * @id: A desktop ID, e.g. "gimp.desktop"
+ *
+ * Gets a a #GDesktopAppInfo taking into account the kde4- prefix.
+ * If the given @id doesn not have a ".desktop" suffix, it will add one to it
+ * for convenience.
+ *
+ * Returns: a #GDesktopAppInfo for a specific ID, or %NULL
+ */
+GDesktopAppInfo *
+gs_utils_get_desktop_app_info (const gchar *id)
+{
+	GDesktopAppInfo *app_info;
+	g_autofree gchar *desktop_id = NULL;
+
+	/* for convenience, if the given id doesn't have the required .desktop
+	 * suffix, we add it here */
+	if (!g_str_has_suffix (id, ".desktop")) {
+		desktop_id = g_strconcat (id, ".desktop", NULL);
+		id = desktop_id;
+	}
+
+	/* try to get the standard app-id */
+	app_info = g_desktop_app_info_new (id);
+
+	/* KDE is a special project because it believes /usr/share/applications
+	 * isn't KDE enough. For this reason we support falling back to the
+	 * "kde4-" prefixed ID to avoid educating various self-righteous
+	 * upstreams about the correct ID to use in the AppData file. */
+	if (app_info == NULL) {
+		g_autofree gchar *kde_id = NULL;
+		kde_id = g_strdup_printf ("%s-%s", "kde4", id);
+		app_info = g_desktop_app_info_new (kde_id);
+	}
+
+	return app_info;
+}
+
+/**
+ * gs_utils_symlink:
+ * @target: the full path of the symlink to create
+ * @linkpath: where the symlink should point to
+ * @error: A #GError, or %NULL
+ *
+ * Creates a symlink that can cross filesystem boundaries.
+ * Any parent directories needed for target to exist are also created.
+ *
+ * Returns: %TRUE for success
+ **/
+gboolean
+gs_utils_symlink (const gchar *target, const gchar *linkpath, GError **error)
+{
+	if (!gs_mkdir_parent (target, error))
+		return FALSE;
+	if (symlink (target, linkpath) != 0) {
+		g_set_error (error,
+			     GS_PLUGIN_ERROR,
+			     GS_PLUGIN_ERROR_WRITE_FAILED,
+			     "failed to create symlink from %s to %s",
+			     linkpath, target);
+		return FALSE;
+	}
+	return TRUE;
+}
+
+/**
+ * gs_utils_unlink:
+ * @filename: A full pathname to delete
+ * @error: A #GError, or %NULL
+ *
+ * Deletes a file from disk.
+ *
+ * Returns: %TRUE for success
+ **/
+gboolean
+gs_utils_unlink (const gchar *filename, GError **error)
+{
+	if (g_unlink (filename) != 0) {
+		g_set_error (error,
+			     GS_PLUGIN_ERROR,
+			     GS_PLUGIN_ERROR_DELETE_FAILED,
+			     "failed to delete %s",
+			     filename);
+		return FALSE;
+	}
+	return TRUE;
+}
+
+static gboolean
+gs_utils_rmtree_real (const gchar *directory, GError **error)
+{
+	const gchar *filename;
+	g_autoptr(GDir) dir = NULL;
+
+	/* try to open */
+	dir = g_dir_open (directory, 0, error);
+	if (dir == NULL)
+		return FALSE;
+
+	/* find each */
+	while ((filename = g_dir_read_name (dir))) {
+		g_autofree gchar *src = NULL;
+		src = g_build_filename (directory, filename, NULL);
+		if (g_file_test (src, G_FILE_TEST_IS_DIR) &&
+		    !g_file_test (src, G_FILE_TEST_IS_SYMLINK)) {
+			if (!gs_utils_rmtree_real (src, error))
+				return FALSE;
+		} else {
+			if (g_unlink (src) != 0) {
+				g_set_error (error,
+					     GS_PLUGIN_ERROR,
+					     GS_PLUGIN_ERROR_DELETE_FAILED,
+					     "Failed to delete: %s", src);
+				return FALSE;
+			}
+		}
+	}
+
+	if (g_rmdir (directory) != 0) {
+		g_set_error (error,
+			     GS_PLUGIN_ERROR,
+			     GS_PLUGIN_ERROR_DELETE_FAILED,
+			     "Failed to remove: %s", directory);
+		return FALSE;
+	}
+	return TRUE;
+}
+
+/**
+ * gs_utils_rmtree:
+ * @directory: A full directory pathname to delete
+ * @error: A #GError, or %NULL
+ *
+ * Deletes a directory from disk and all its contents.
+ *
+ * Returns: %TRUE for success
+ **/
+gboolean
+gs_utils_rmtree (const gchar *directory, GError **error)
+{
+	g_debug ("recursively removing directory '%s'", directory);
+	return gs_utils_rmtree_real (directory, error);
+}
+
+static gdouble
+pnormaldist (gdouble qn)
+{
+	static gdouble b[11] = { 1.570796288,      0.03706987906,   -0.8364353589e-3,
+				-0.2250947176e-3,  0.6841218299e-5,  0.5824238515e-5,
+				-0.104527497e-5,   0.8360937017e-7, -0.3231081277e-8,
+				 0.3657763036e-10, 0.6936233982e-12 };
+	gdouble w1, w3;
+	guint i;
+
+	if (qn < 0 || qn > 1)
+		return 0; // This is an error case
+	if (qn == 0.5)
+		return 0;
+
+	w1 = qn;
+	if (qn > 0.5)
+		w1 = 1.0 - w1;
+	w3 = -log (4.0 * w1 * (1.0 - w1));
+	w1 = b[0];
+	for (i = 1; i < 11; i++)
+		w1 = w1 + (b[i] * pow (w3, i));
+
+	if (qn > 0.5)
+		return sqrt (w1 * w3);
+	else
+		return -sqrt (w1 * w3);
+}
+
+static gdouble
+wilson_score (gdouble value, gdouble n, gdouble power)
+{
+	gdouble z, phat;
+	if (value == 0)
+		return 0;
+	z = pnormaldist (1 - power / 2);
+	phat = value / n;
+	return (phat + z * z / (2 * n) -
+		z * sqrt ((phat * (1 - phat) + z * z / (4 * n)) / n)) /
+		(1 + z * z / n);
+}
+
+/**
+ * gs_utils_get_wilson_rating:
+ * @star1: The number of 1 star reviews
+ * @star2: The number of 2 star reviews
+ * @star3: The number of 3 star reviews
+ * @star4: The number of 4 star reviews
+ * @star5: The number of 5 star reviews
+ *
+ * Returns the lower bound of Wilson score confidence interval for a
+ * Bernoulli parameter. This ensures small numbers of ratings don't give overly
+ * high scores.
+ * See https://en.wikipedia.org/wiki/Binomial_proportion_confidence_interval
+ * for details.
+ *
+ * Returns: Wilson rating percentage, or -1 for error
+ **/
+gint
+gs_utils_get_wilson_rating (guint64 star1,
+			    guint64 star2,
+			    guint64 star3,
+			    guint64 star4,
+			    guint64 star5)
+{
+	gdouble val;
+	guint64 star_sum = star1 + star2 + star3 + star4 + star5;
+	if (star_sum == 0)
+		return -1;
+
+	/* get score */
+	val =  (wilson_score ((gdouble) star1, (gdouble) star_sum, 0.2) * -2);
+	val += (wilson_score ((gdouble) star2, (gdouble) star_sum, 0.2) * -1);
+	val += (wilson_score ((gdouble) star4, (gdouble) star_sum, 0.2) * 1);
+	val += (wilson_score ((gdouble) star5, (gdouble) star_sum, 0.2) * 2);
+
+	/* normalize from -2..+2 to 0..5 */
+	val += 3;
+
+	/* multiply to a percentage */
+	val *= 20;
+
+	/* return rounded up integer */
+	return (gint) ceil (val);
+}
+
+/**
+ * gs_utils_error_add_app_id:
+ * @error: a #GError
+ * @app: a #GsApp
+ *
+ * Adds app unique ID prefix to the error.
+ *
+ * Since: 3.30
+ **/
+void
+gs_utils_error_add_app_id (GError **error, GsApp *app)
+{
+	g_return_if_fail (GS_APP (app));
+	if (error == NULL || *error == NULL)
+		return;
+	g_prefix_error (error, "{%s} ", gs_app_get_unique_id (app));
+}
+
+/**
+ * gs_utils_error_add_origin_id:
+ * @error: a #GError
+ * @origin: a #GsApp
+ *
+ * Adds origin unique ID prefix to the error.
+ *
+ * Since: 3.30
+ **/
+void
+gs_utils_error_add_origin_id (GError **error, GsApp *origin)
+{
+	g_return_if_fail (GS_APP (origin));
+	if (error == NULL || *error == NULL)
+		return;
+	g_prefix_error (error, "[%s] ", gs_app_get_unique_id (origin));
+}
+
+/**
+ * gs_utils_error_strip_app_id:
+ * @error: a #GError
+ *
+ * Removes a possible app ID prefix from the error, and returns the removed
+ * app ID.
+ *
+ * Returns: A newly allocated string with the app ID
+ *
+ * Since: 3.30
+ **/
+gchar *
+gs_utils_error_strip_app_id (GError *error)
+{
+	g_autofree gchar *app_id = NULL;
+	g_autofree gchar *msg = NULL;
+
+	if (error == NULL || error->message == NULL)
+		return FALSE;
+
+	if (g_str_has_prefix (error->message, "{")) {
+		const gchar *endp = strstr (error->message + 1, "} ");
+		if (endp != NULL) {
+			app_id = g_strndup (error->message + 1,
+			                    endp - (error->message + 1));
+			msg = g_strdup (endp + 2);
+		}
+	}
+
+	if (msg != NULL) {
+		g_free (error->message);
+		error->message = g_steal_pointer (&msg);
+	}
+
+	return g_steal_pointer (&app_id);
+}
+
+/**
+ * gs_utils_error_strip_origin_id:
+ * @error: a #GError
+ *
+ * Removes a possible origin ID prefix from the error, and returns the removed
+ * origin ID.
+ *
+ * Returns: A newly allocated string with the origin ID
+ *
+ * Since: 3.30
+ **/
+gchar *
+gs_utils_error_strip_origin_id (GError *error)
+{
+	g_autofree gchar *origin_id = NULL;
+	g_autofree gchar *msg = NULL;
+
+	if (error == NULL || error->message == NULL)
+		return FALSE;
+
+	if (g_str_has_prefix (error->message, "[")) {
+		const gchar *endp = strstr (error->message + 1, "] ");
+		if (endp != NULL) {
+			origin_id = g_strndup (error->message + 1,
+			                       endp - (error->message + 1));
+			msg = g_strdup (endp + 2);
+		}
+	}
+
+	if (msg != NULL) {
+		g_free (error->message);
+		error->message = g_steal_pointer (&msg);
+	}
+
+	return g_steal_pointer (&origin_id);
+}
+
+/**
+ * gs_utils_error_convert_gdbus:
+ * @perror: a pointer to a #GError, or %NULL
+ *
+ * Converts the #GDBusError to an error with a GsPluginError domain.
+ *
+ * Returns: %TRUE if the error was converted, or already correct
+ **/
+gboolean
+gs_utils_error_convert_gdbus (GError **perror)
+{
+	GError *error = perror != NULL ? *perror : NULL;
+
+	/* not set */
+	if (error == NULL)
+		return FALSE;
+	if (error->domain == GS_PLUGIN_ERROR)
+		return TRUE;
+	if (error->domain != G_DBUS_ERROR)
+		return FALSE;
+	switch (error->code) {
+	case G_DBUS_ERROR_FAILED:
+	case G_DBUS_ERROR_NO_REPLY:
+	case G_DBUS_ERROR_TIMEOUT:
+		error->code = GS_PLUGIN_ERROR_FAILED;
+		break;
+	case G_DBUS_ERROR_IO_ERROR:
+	case G_DBUS_ERROR_NAME_HAS_NO_OWNER:
+	case G_DBUS_ERROR_NOT_SUPPORTED:
+	case G_DBUS_ERROR_SERVICE_UNKNOWN:
+	case G_DBUS_ERROR_UNKNOWN_INTERFACE:
+	case G_DBUS_ERROR_UNKNOWN_METHOD:
+	case G_DBUS_ERROR_UNKNOWN_OBJECT:
+	case G_DBUS_ERROR_UNKNOWN_PROPERTY:
+		error->code = GS_PLUGIN_ERROR_NOT_SUPPORTED;
+		break;
+	case G_DBUS_ERROR_NO_MEMORY:
+		error->code = GS_PLUGIN_ERROR_NO_SPACE;
+		break;
+	case G_DBUS_ERROR_ACCESS_DENIED:
+	case G_DBUS_ERROR_AUTH_FAILED:
+		error->code = GS_PLUGIN_ERROR_NO_SECURITY;
+		break;
+	case G_DBUS_ERROR_NO_NETWORK:
+		error->code = GS_PLUGIN_ERROR_NO_NETWORK;
+		break;
+	case G_DBUS_ERROR_INVALID_FILE_CONTENT:
+		error->code = GS_PLUGIN_ERROR_INVALID_FORMAT;
+		break;
+	default:
+		g_warning ("can't reliably fixup error code %i in domain %s",
+			   error->code, g_quark_to_string (error->domain));
+		error->code = GS_PLUGIN_ERROR_FAILED;
+		break;
+	}
+	error->domain = GS_PLUGIN_ERROR;
+	return TRUE;
+}
+
+/**
+ * gs_utils_error_convert_gio:
+ * @perror: a pointer to a #GError, or %NULL
+ *
+ * Converts the #GIOError to an error with a GsPluginError domain.
+ *
+ * Returns: %TRUE if the error was converted, or already correct
+ **/
+gboolean
+gs_utils_error_convert_gio (GError **perror)
+{
+	GError *error = perror != NULL ? *perror : NULL;
+
+	/* not set */
+	if (error == NULL)
+		return FALSE;
+	if (error->domain == GS_PLUGIN_ERROR)
+		return TRUE;
+	if (error->domain != G_IO_ERROR)
+		return FALSE;
+	switch (error->code) {
+	case G_IO_ERROR_FAILED:
+	case G_IO_ERROR_NOT_FOUND:
+	case G_IO_ERROR_EXISTS:
+		error->code = GS_PLUGIN_ERROR_FAILED;
+		break;
+	case G_IO_ERROR_TIMED_OUT:
+		error->code = GS_PLUGIN_ERROR_TIMED_OUT;
+		break;
+	case G_IO_ERROR_NOT_SUPPORTED:
+		error->code = GS_PLUGIN_ERROR_NOT_SUPPORTED;
+		break;
+	case G_IO_ERROR_CANCELLED:
+		error->code = GS_PLUGIN_ERROR_CANCELLED;
+		break;
+	case G_IO_ERROR_NO_SPACE:
+		error->code = GS_PLUGIN_ERROR_NO_SPACE;
+		break;
+	case G_IO_ERROR_PERMISSION_DENIED:
+		error->code = GS_PLUGIN_ERROR_NO_SECURITY;
+		break;
+	case G_IO_ERROR_HOST_NOT_FOUND:
+	case G_IO_ERROR_HOST_UNREACHABLE:
+	case G_IO_ERROR_CONNECTION_REFUSED:
+	case G_IO_ERROR_PROXY_FAILED:
+	case G_IO_ERROR_PROXY_AUTH_FAILED:
+	case G_IO_ERROR_PROXY_NOT_ALLOWED:
+		error->code = GS_PLUGIN_ERROR_DOWNLOAD_FAILED;
+		break;
+	case G_IO_ERROR_NETWORK_UNREACHABLE:
+		error->code = GS_PLUGIN_ERROR_NO_NETWORK;
+		break;
+	default:
+		g_warning ("can't reliably fixup error code %i in domain %s",
+			   error->code, g_quark_to_string (error->domain));
+		error->code = GS_PLUGIN_ERROR_FAILED;
+		break;
+	}
+	error->domain = GS_PLUGIN_ERROR;
+	return TRUE;
+}
+
+/**
+ * gs_utils_error_convert_gresolver:
+ * @perror: a pointer to a #GError, or %NULL
+ *
+ * Converts the #GResolverError to an error with a GsPluginError domain.
+ *
+ * Returns: %TRUE if the error was converted, or already correct
+ **/
+gboolean
+gs_utils_error_convert_gresolver (GError **perror)
+{
+	GError *error = perror != NULL ? *perror : NULL;
+
+	/* not set */
+	if (error == NULL)
+		return FALSE;
+	if (error->domain == GS_PLUGIN_ERROR)
+		return TRUE;
+	if (error->domain != G_RESOLVER_ERROR)
+		return FALSE;
+	switch (error->code) {
+	case G_RESOLVER_ERROR_INTERNAL:
+		error->code = GS_PLUGIN_ERROR_FAILED;
+		break;
+	case G_RESOLVER_ERROR_NOT_FOUND:
+	case G_RESOLVER_ERROR_TEMPORARY_FAILURE:
+		error->code = GS_PLUGIN_ERROR_DOWNLOAD_FAILED;
+		break;
+	default:
+		g_warning ("can't reliably fixup error code %i in domain %s",
+			   error->code, g_quark_to_string (error->domain));
+		error->code = GS_PLUGIN_ERROR_FAILED;
+		break;
+	}
+	error->domain = GS_PLUGIN_ERROR;
+	return TRUE;
+}
+
+/**
+ * gs_utils_error_convert_gdk_pixbuf:
+ * @perror: a pointer to a #GError, or %NULL
+ *
+ * Converts the #GdkPixbufError to an error with a GsPluginError domain.
+ *
+ * Returns: %TRUE if the error was converted, or already correct
+ **/
+gboolean
+gs_utils_error_convert_gdk_pixbuf (GError **perror)
+{
+	GError *error = perror != NULL ? *perror : NULL;
+
+	/* not set */
+	if (error == NULL)
+		return FALSE;
+	if (error->domain == GS_PLUGIN_ERROR)
+		return TRUE;
+	if (error->domain != GDK_PIXBUF_ERROR)
+		return FALSE;
+	switch (error->code) {
+	case GDK_PIXBUF_ERROR_UNSUPPORTED_OPERATION:
+	case GDK_PIXBUF_ERROR_UNKNOWN_TYPE:
+		error->code = GS_PLUGIN_ERROR_NOT_SUPPORTED;
+		break;
+	case GDK_PIXBUF_ERROR_FAILED:
+		error->code = GS_PLUGIN_ERROR_FAILED;
+		break;
+	case GDK_PIXBUF_ERROR_CORRUPT_IMAGE:
+		error->code = GS_PLUGIN_ERROR_INVALID_FORMAT;
+		break;
+	default:
+		g_warning ("can't reliably fixup error code %i in domain %s",
+			   error->code, g_quark_to_string (error->domain));
+		error->code = GS_PLUGIN_ERROR_FAILED;
+		break;
+	}
+	error->domain = GS_PLUGIN_ERROR;
+	return TRUE;
+}
+
+/**
+ * gs_utils_error_convert_appstream:
+ * @perror: a pointer to a #GError, or %NULL
+ *
+ * Converts the various AppStream error types to an error with a GsPluginError
+ * domain.
+ *
+ * Returns: %TRUE if the error was converted, or already correct
+ **/
+gboolean
+gs_utils_error_convert_appstream (GError **perror)
+{
+	GError *error = perror != NULL ? *perror : NULL;
+
+	/* not set */
+	if (error == NULL)
+		return FALSE;
+	if (error->domain == GS_PLUGIN_ERROR)
+		return TRUE;
+
+	/* custom to this plugin */
+	if (error->domain == AS_METADATA_ERROR) {
+		switch (error->code) {
+		case AS_METADATA_ERROR_PARSE:
+		case AS_METADATA_ERROR_FORMAT_UNEXPECTED:
+		case AS_METADATA_ERROR_NO_COMPONENT:
+			error->code = GS_PLUGIN_ERROR_INVALID_FORMAT;
+			break;
+		case AS_METADATA_ERROR_FAILED:
+		default:
+			error->code = GS_PLUGIN_ERROR_FAILED;
+			break;
+		}
+	} else if (error->domain == AS_POOL_ERROR) {
+		switch (error->code) {
+		case AS_POOL_ERROR_FAILED:
+		default:
+			error->code = GS_PLUGIN_ERROR_FAILED;
+			break;
+		}
+	} else if (error->domain == G_FILE_ERROR) {
+		switch (error->code) {
+		case G_FILE_ERROR_EXIST:
+		case G_FILE_ERROR_ACCES:
+		case G_FILE_ERROR_PERM:
+			error->code = GS_PLUGIN_ERROR_NO_SECURITY;
+			break;
+		case G_FILE_ERROR_NOSPC:
+			error->code = GS_PLUGIN_ERROR_NO_SPACE;
+			break;
+		default:
+			error->code = GS_PLUGIN_ERROR_FAILED;
+			break;
+		}
+	} else {
+		g_warning ("can't reliably fixup error from domain %s",
+			   g_quark_to_string (error->domain));
+		error->code = GS_PLUGIN_ERROR_FAILED;
+	}
+	error->domain = GS_PLUGIN_ERROR;
+	return TRUE;
+}
+
+/**
+ * gs_utils_get_url_scheme:
+ * @url: A URL, e.g. "appstream://gimp.desktop"
+ *
+ * Gets the scheme from the URL string.
+ *
+ * Returns: the URL scheme, e.g. "appstream"
+ */
+gchar *
+gs_utils_get_url_scheme	(const gchar *url)
+{
+	g_autoptr(GUri) uri = NULL;
+
+	/* no data */
+	if (url == NULL)
+		return NULL;
+
+	/* create URI from URL */
+	uri = g_uri_parse (url, SOUP_HTTP_URI_FLAGS, NULL);
+	if (!uri)
+		return NULL;
+
+	/* success */
+	return g_strdup (g_uri_get_scheme (uri));
+}
+
+/**
+ * gs_utils_get_url_path:
+ * @url: A URL, e.g. "appstream://gimp.desktop"
+ *
+ * Gets the path from the URL string, removing any leading slashes.
+ *
+ * Returns: the URL path, e.g. "gimp.desktop"
+ */
+gchar *
+gs_utils_get_url_path (const gchar *url)
+{
+	g_autoptr(GUri) uri = NULL;
+	const gchar *host;
+	const gchar *path;
+
+	uri = g_uri_parse (url, SOUP_HTTP_URI_FLAGS, NULL);
+	if (!uri)
+		return NULL;
+
+	/* foo://bar -> scheme: foo, host: bar, path: / */
+	/* foo:bar -> scheme: foo, host: (empty string), path: /bar */
+	host = g_uri_get_host (uri);
+	path = g_uri_get_path (uri);
+	if (host != NULL && *host != '\0')
+		path = host;
+
+	/* trim any leading slashes */
+	while (*path == '/')
+		path++;
+
+	/* success */
+	return g_strdup (path);
+}
+
+/**
+ * gs_user_agent:
+ *
+ * Gets the user agent to use for remote requests.
+ *
+ * Returns: the user-agent, e.g. "gnome-software/3.22.1"
+ */
+const gchar *
+gs_user_agent (void)
+{
+	return PACKAGE_NAME "/" PACKAGE_VERSION;
+}
+
+/**
+ * gs_utils_append_key_value:
+ * @str: A #GString
+ * @align_len: The alignment of the @value compared to the @key
+ * @key: The text to use as a title
+ * @value: The text to use as a value
+ *
+ * Adds a line to an existing string, padding the key to a set number of spaces.
+ *
+ * Since: 3.26
+ */
+void
+gs_utils_append_key_value (GString *str, gsize align_len,
+			   const gchar *key, const gchar *value)
+{
+	gsize len = 0;
+
+	g_return_if_fail (str != NULL);
+	g_return_if_fail (value != NULL);
+
+	if (key != NULL) {
+		len = strlen (key) + 2;
+		g_string_append (str, key);
+		g_string_append (str, ": ");
+	}
+	for (gsize i = len; i < align_len + 1; i++)
+		g_string_append (str, " ");
+	g_string_append (str, value);
+	g_string_append (str, "\n");
+}
+
+guint
+gs_utils_get_memory_total (void)
+{
+#if defined(__linux__)
+	struct sysinfo si = { 0 };
+	sysinfo (&si);
+	if (si.mem_unit > 0)
+		return si.totalram / MB_IN_BYTES / si.mem_unit;
+	return 0;
+#elif defined(__FreeBSD__)
+	unsigned long physmem;
+	sysctl ((int[]){ CTL_HW, HW_PHYSMEM }, 2, &physmem, &(size_t){ sizeof (physmem) }, NULL, 0);
+	return physmem / MB_IN_BYTES;
+#else
+#error "Please implement gs_utils_get_memory_total for your system."
+#endif
+}
+
+/**
+ * gs_utils_set_online_updates_timestamp:
+ *
+ * Sets the value of online-updates-timestamp to current epoch. "online-updates-timestamp" represents
+ * the last time the system was online and got any updates.
+ **/
+void
+gs_utils_set_online_updates_timestamp (GSettings *settings)
+{
+	g_autoptr(GDateTime) now = NULL;
+
+	g_return_if_fail (settings != NULL);
+
+	now = g_date_time_new_now_local ();
+	g_settings_set (settings, "online-updates-timestamp", "x", g_date_time_to_unix (now));
+}
+
+/**
+ * gs_utils_unique_id_compat_convert:
+ * @data_id: (nullable): A string that may be a unique component ID
+ *
+ * Converts the unique ID string from its legacy 6-part form into
+ * a new-style 5-part AppStream data-id.
+ * Does nothing if the string is already valid.
+ *
+ * See !583 for the history of this conversion.
+ *
+ * Returns: (nullable): A newly allocated string with the new-style data-id, or %NULL if input was no valid ID.
+ *
+ * Since: 40
+ **/
+gchar*
+gs_utils_unique_id_compat_convert (const gchar *data_id)
+{
+	g_auto(GStrv) parts = NULL;
+	if (data_id == NULL)
+		return NULL;
+
+	/* check for the most common case first: data-id is already valid */
+	if (as_utils_data_id_valid (data_id))
+		return g_strdup (data_id);
+
+	parts = g_strsplit (data_id, "/", -1);
+	if (g_strv_length (parts) != 6)
+		return NULL;
+	return g_strdup_printf ("%s/%s/%s/%s/%s",
+				parts[0],
+				parts[1],
+				parts[2],
+				parts[4],
+				parts[5]);
+}
+
+static const gchar *
+_fix_data_id_part (const gchar *value)
+{
+	if (!value || !*value)
+		return "*";
+
+	return value;
+}
+
+/**
+ * gs_utils_build_unique_id:
+ * @scope: Scope of the metadata as #AsComponentScope e.g. %AS_COMPONENT_SCOPE_SYSTEM
+ * @bundle_kind: Bundling system providing this data, e.g. 'package' or 'flatpak'
+ * @origin: Origin string, e.g. 'os' or 'gnome-apps-nightly'
+ * @cid: AppStream component ID, e.g. 'org.freedesktop.appstream.cli'
+ * @branch: Branch, e.g. '3-20' or 'master'
+ *
+ * Builds an identifier string unique to the individual dataset using the supplied information.
+ * It's similar to as_utils_build_data_id(), except it respects the @origin for the packages.
+ *
+ * Returns: (transfer full): a unique ID, free with g_free(), when no longer needed.
+ *
+ * Since: 41
+ */
+gchar *
+gs_utils_build_unique_id (AsComponentScope scope,
+			  AsBundleKind bundle_kind,
+			  const gchar *origin,
+			  const gchar *cid,
+			  const gchar *branch)
+{
+	const gchar *scope_str = NULL;
+	const gchar *bundle_str = NULL;
+
+	if (scope != AS_COMPONENT_SCOPE_UNKNOWN)
+		scope_str = as_component_scope_to_string (scope);
+	if (bundle_kind != AS_BUNDLE_KIND_UNKNOWN)
+		bundle_str = as_bundle_kind_to_string (bundle_kind);
+
+	return g_strdup_printf ("%s/%s/%s/%s/%s",
+				_fix_data_id_part (scope_str),
+				_fix_data_id_part (bundle_str),
+				_fix_data_id_part (origin),
+				_fix_data_id_part (cid),
+				_fix_data_id_part (branch));
+}
+
+static void
+gs_pixbuf_blur_private (GdkPixbuf *src, GdkPixbuf *dest, guint radius, guint8 *div_kernel_size)
+{
+	gint width, height, src_rowstride, dest_rowstride, n_channels;
+	guchar *p_src, *p_dest, *c1, *c2;
+	gint x, y, i, i1, i2, width_minus_1, height_minus_1, radius_plus_1;
+	gint r, g, b;
+	guchar *p_dest_row, *p_dest_col;
+
+	width = gdk_pixbuf_get_width (src);
+	height = gdk_pixbuf_get_height (src);
+	n_channels = gdk_pixbuf_get_n_channels (src);
+	radius_plus_1 = radius + 1;
+
+	/* horizontal blur */
+	p_src = gdk_pixbuf_get_pixels (src);
+	p_dest = gdk_pixbuf_get_pixels (dest);
+	src_rowstride = gdk_pixbuf_get_rowstride (src);
+	dest_rowstride = gdk_pixbuf_get_rowstride (dest);
+	width_minus_1 = width - 1;
+	for (y = 0; y < height; y++) {
+
+		/* calc the initial sums of the kernel */
+		r = g = b = 0;
+		for (i = -radius; i <= (gint) radius; i++) {
+			c1 = p_src + (CLAMP (i, 0, width_minus_1) * n_channels);
+			r += c1[0];
+			g += c1[1];
+			b += c1[2];
+		}
+
+		p_dest_row = p_dest;
+		for (x = 0; x < width; x++) {
+			/* set as the mean of the kernel */
+			p_dest_row[0] = div_kernel_size[r];
+			p_dest_row[1] = div_kernel_size[g];
+			p_dest_row[2] = div_kernel_size[b];
+			p_dest_row += n_channels;
+
+			/* the pixel to add to the kernel */
+			i1 = x + radius_plus_1;
+			if (i1 > width_minus_1)
+				i1 = width_minus_1;
+			c1 = p_src + (i1 * n_channels);
+
+			/* the pixel to remove from the kernel */
+			i2 = x - radius;
+			if (i2 < 0)
+				i2 = 0;
+			c2 = p_src + (i2 * n_channels);
+
+			/* calc the new sums of the kernel */
+			r += c1[0] - c2[0];
+			g += c1[1] - c2[1];
+			b += c1[2] - c2[2];
+		}
+
+		p_src += src_rowstride;
+		p_dest += dest_rowstride;
+	}
+
+	/* vertical blur */
+	p_src = gdk_pixbuf_get_pixels (dest);
+	p_dest = gdk_pixbuf_get_pixels (src);
+	src_rowstride = gdk_pixbuf_get_rowstride (dest);
+	dest_rowstride = gdk_pixbuf_get_rowstride (src);
+	height_minus_1 = height - 1;
+	for (x = 0; x < width; x++) {
+
+		/* calc the initial sums of the kernel */
+		r = g = b = 0;
+		for (i = -radius; i <= (gint) radius; i++) {
+			c1 = p_src + (CLAMP (i, 0, height_minus_1) * src_rowstride);
+			r += c1[0];
+			g += c1[1];
+			b += c1[2];
+		}
+
+		p_dest_col = p_dest;
+		for (y = 0; y < height; y++) {
+			/* set as the mean of the kernel */
+
+			p_dest_col[0] = div_kernel_size[r];
+			p_dest_col[1] = div_kernel_size[g];
+			p_dest_col[2] = div_kernel_size[b];
+			p_dest_col += dest_rowstride;
+
+			/* the pixel to add to the kernel */
+			i1 = y + radius_plus_1;
+			if (i1 > height_minus_1)
+				i1 = height_minus_1;
+			c1 = p_src + (i1 * src_rowstride);
+
+			/* the pixel to remove from the kernel */
+			i2 = y - radius;
+			if (i2 < 0)
+				i2 = 0;
+			c2 = p_src + (i2 * src_rowstride);
+
+			/* calc the new sums of the kernel */
+			r += c1[0] - c2[0];
+			g += c1[1] - c2[1];
+			b += c1[2] - c2[2];
+		}
+
+		p_src += n_channels;
+		p_dest += n_channels;
+	}
+}
+
+/**
+ * gs_utils_pixbuf_blur:
+ * @src: the GdkPixbuf.
+ * @radius: the pixel radius for the gaussian blur, typical values are 1..3
+ * @iterations: Amount to blur the image, typical values are 1..5
+ *
+ * Blurs an image. Warning, this method is s..l..o..w... for large images.
+ **/
+void
+gs_utils_pixbuf_blur (GdkPixbuf *src, guint radius, guint iterations)
+{
+	gint kernel_size;
+	gint i;
+	g_autofree guchar *div_kernel_size = NULL;
+	g_autoptr(GdkPixbuf) tmp = NULL;
+
+	tmp = gdk_pixbuf_new (gdk_pixbuf_get_colorspace (src),
+			      gdk_pixbuf_get_has_alpha (src),
+			      gdk_pixbuf_get_bits_per_sample (src),
+			      gdk_pixbuf_get_width (src),
+			      gdk_pixbuf_get_height (src));
+	kernel_size = 2 * radius + 1;
+	div_kernel_size = g_new (guchar, 256 * kernel_size);
+	for (i = 0; i < 256 * kernel_size; i++)
+		div_kernel_size[i] = (guchar) (i / kernel_size);
+
+	while (iterations-- > 0)
+		gs_pixbuf_blur_private (src, tmp, radius, div_kernel_size);
+}
+
+/**
+ * gs_utils_get_file_size:
+ * @filename: a file name to get the size of; it can be a file or a directory
+ * @include_func: (nullable) (scope call): optional callback to limit what files to count
+ * @user_data: user data passed to the @include_func
+ * @cancellable: (nullable): an optional #GCancellable or %NULL
+ *
+ * Gets the size of the file or a directory identified by @filename.
+ *
+ * When the @include_func is not %NULL, it can limit which files are included
+ * in the resulting size. When it's %NULL, all files and subdirectories are included.
+ *
+ * Returns: disk size of the @filename; or 0 when not found
+ *
+ * Since: 41
+ **/
+guint64
+gs_utils_get_file_size (const gchar *filename,
+			GsFileSizeIncludeFunc include_func,
+			gpointer user_data,
+			GCancellable *cancellable)
+{
+	guint64 size = 0;
+
+	g_return_val_if_fail (filename != NULL, 0);
+
+	if (g_file_test (filename, G_FILE_TEST_IS_DIR)) {
+		GSList *dirs_to_do = NULL;
+		gsize base_len = strlen (filename);
+
+		/* The `include_func()` expects a path relative to the `filename`, without
+		   a leading dir separator. As the `dirs_to_do` contains the full path,
+		   constructed with `g_build_filename()`, the added dir separator needs
+		   to be skipped, when it's not part of the `filename` already. */
+		if (!g_str_has_suffix (filename, G_DIR_SEPARATOR_S))
+			base_len++;
+
+		dirs_to_do = g_slist_prepend (dirs_to_do, g_strdup (filename));
+		while (dirs_to_do != NULL && !g_cancellable_is_cancelled (cancellable)) {
+			g_autofree gchar *path = NULL;
+			g_autoptr(GDir) dir = NULL;
+
+			/* Steal the top `path` out of the `dirs_to_do`. */
+			path = dirs_to_do->data;
+			dirs_to_do = g_slist_remove (dirs_to_do, path);
+
+			dir = g_dir_open (path, 0, NULL);
+			if (dir) {
+				const gchar *name;
+				while (name = g_dir_read_name (dir), name != NULL && !g_cancellable_is_cancelled (cancellable)) {
+					g_autofree gchar *full_path = g_build_filename (path, name, NULL);
+					GStatBuf st;
+
+					if (g_stat (full_path, &st) == 0 && (include_func == NULL ||
+					    include_func (full_path + base_len,
+							  g_file_test (full_path, G_FILE_TEST_IS_SYMLINK) ? G_FILE_TEST_IS_SYMLINK :
+							  S_ISDIR (st.st_mode) ? G_FILE_TEST_IS_DIR :
+							  G_FILE_TEST_IS_REGULAR,
+							  user_data))) {
+						if (S_ISDIR (st.st_mode)) {
+							/* Skip symlinks, they can point to a shared storage */
+							if (!g_file_test (full_path, G_FILE_TEST_IS_SYMLINK))
+								dirs_to_do = g_slist_prepend (dirs_to_do, g_steal_pointer (&full_path));
+						} else {
+							size += st.st_size;
+						}
+					}
+				}
+			}
+		}
+		g_slist_free_full (dirs_to_do, g_free);
+	} else {
+		GStatBuf st;
+
+		if (g_stat (filename, &st) == 0)
+			size = st.st_size;
+	}
+
+	return size;
+}
+
+#define METADATA_ETAG_ATTRIBUTE "xattr::gnome-software::etag"
+
+/**
+ * gs_utils_get_file_etag:
+ * @file: a file to get the ETag for
+ * @last_modified_date_out: (out callee-allocates) (transfer full) (optional) (nullable):
+ *   return location for the last modified date of the file (%NULL to ignore),
+ *   or %NULL if unknown
+ * @cancellable: (nullable): an optional #GCancellable or %NULL
+ *
+ * Gets the ETag for the @file, previously stored by
+ * gs_utils_set_file_etag().
+ *
+ * Returns: (nullable) (transfer full): The ETag stored for the @file,
+ *    or %NULL, when the file does not exist, no ETag is stored for it
+ *    or other error occurs.
+ *
+ * Since: 43
+ **/
+gchar *
+gs_utils_get_file_etag (GFile         *file,
+                        GDateTime    **last_modified_date_out,
+                        GCancellable  *cancellable)
+{
+	g_autoptr(GFileInfo) info = NULL;
+	const gchar *attributes;
+	g_autoptr(GError) local_error = NULL;
+
+	g_return_val_if_fail (G_IS_FILE (file), NULL);
+	g_return_val_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable), NULL);
+
+	if (last_modified_date_out == NULL)
+		attributes = METADATA_ETAG_ATTRIBUTE;
+	else
+		attributes = METADATA_ETAG_ATTRIBUTE "," G_FILE_ATTRIBUTE_TIME_MODIFIED;
+
+	info = g_file_query_info (file, attributes, G_FILE_QUERY_INFO_NONE, cancellable, &local_error);
+
+	if (info == NULL) {
+		g_debug ("Error getting attribute ‘%s’ for file ‘%s’: %s",
+			 METADATA_ETAG_ATTRIBUTE, g_file_peek_path (file), local_error->message);
+
+		if (last_modified_date_out != NULL)
+			*last_modified_date_out = NULL;
+
+		return NULL;
+	}
+
+	if (last_modified_date_out != NULL)
+		*last_modified_date_out = g_file_info_get_modification_date_time (info);
+
+	return g_strdup (g_file_info_get_attribute_string (info, METADATA_ETAG_ATTRIBUTE));
+}
+
+/**
+ * gs_utils_set_file_etag:
+ * @file: a file to get the ETag for
+ * @etag: (nullable): an ETag to set
+ * @cancellable: (nullable): an optional #GCancellable or %NULL
+ *
+ * Sets the ETag for the @file. When the @etag is %NULL or an empty
+ * string, then unsets the ETag for the @file. The ETag can be read
+ * back with gs_utils_get_file_etag().
+ *
+ * The @file should exist, otherwise the function fails.
+ *
+ * Returns: whether succeeded.
+ *
+ * Since: 42
+ **/
+gboolean
+gs_utils_set_file_etag (GFile        *file,
+                        const gchar  *etag,
+                        GCancellable *cancellable)
+{
+	g_autoptr(GError) local_error = NULL;
+
+	g_return_val_if_fail (G_IS_FILE (file), FALSE);
+	g_return_val_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable), FALSE);
+
+	if (etag == NULL || *etag == '\0') {
+		if (!g_file_set_attribute (file, METADATA_ETAG_ATTRIBUTE, G_FILE_ATTRIBUTE_TYPE_INVALID,
+					   NULL, G_FILE_QUERY_INFO_NONE, cancellable, &local_error)) {
+			g_debug ("Error clearing attribute ‘%s’ on file ‘%s’: %s",
+				 METADATA_ETAG_ATTRIBUTE, g_file_peek_path (file), local_error->message);
+			return FALSE;
+		}
+
+		return TRUE;
+	}
+
+	if (!g_file_set_attribute_string (file, METADATA_ETAG_ATTRIBUTE, etag, G_FILE_QUERY_INFO_NONE, cancellable, &local_error)) {
+		g_debug ("Error setting attribute ‘%s’ to ‘%s’ on file ‘%s’: %s",
+			 METADATA_ETAG_ATTRIBUTE, etag, g_file_peek_path (file), local_error->message);
+		return FALSE;
+	}
+
+	return TRUE;
+}
+
+/**
+ * gs_utils_get_upgrade_background:
+ * @version: (nullable): version string of the upgrade (which must be non-empty
+ *   if provided), or %NULL if unknown
+ *
+ * Get the path to a background image to display as the background for a banner
+ * advertising an upgrade to the given @version.
+ *
+ * If a path is returned, it’s guaranteed to exist on the file system.
+ *
+ * Vendors can drop their customised backgrounds in this directory for them to
+ * be used by gnome-software. See `doc/vendor-customisation.md`.
+ *
+ * Returns: (transfer full) (type filename) (nullable): path to an upgrade
+ *   background image to use, or %NULL if a suitable one didn’t exist
+ * Since: 42
+*/
+gchar *
+gs_utils_get_upgrade_background (const gchar *version)
+{
+	g_autofree gchar *filename = NULL;
+	g_autofree gchar *os_id = g_get_os_info (G_OS_INFO_KEY_ID);
+
+	g_return_val_if_fail (version == NULL || *version != '\0', NULL);
+
+	if (version != NULL) {
+		filename = g_strdup_printf (DATADIR "/gnome-software/backgrounds/%s-%s.png", os_id, version);
+		if (g_file_test (filename, G_FILE_TEST_EXISTS))
+			return g_steal_pointer (&filename);
+		g_clear_pointer (&filename, g_free);
+	}
+
+	filename = g_strdup_printf (DATADIR "/gnome-software/backgrounds/%s.png", os_id);
+	if (g_file_test (filename, G_FILE_TEST_EXISTS))
+		return g_steal_pointer (&filename);
+	g_clear_pointer (&filename, g_free);
+
+	return NULL;
+}
+
+/**
+ * gs_utils_app_sort_name:
+ * @app1: a #GsApp
+ * @app2: another #GsApp
+ * @user_data: data passed to the sort function
+ *
+ * Comparison function to sort apps in increasing alphabetical order of name.
+ *
+ * This is suitable for passing to gs_app_list_sort().
+ *
+ * Returns: a strcmp()-style sort value comparing @app1 to @app2
+ * Since: 43
+ */
+gint
+gs_utils_app_sort_name (GsApp    *app1,
+                        GsApp    *app2,
+                        gpointer  user_data)
+{
+	return gs_utils_sort_strcmp (gs_app_get_name (app1), gs_app_get_name (app2));
+}
+
+/**
+ * gs_utils_app_sort_match_value:
+ * @app1: a #GsApp
+ * @app2: another #GsApp
+ * @user_data: data passed to the sort function
+ *
+ * Comparison function to sort apps in decreasing order of match value
+ * (#GsApp:match-value).
+ *
+ * This is suitable for passing to gs_app_list_sort().
+ *
+ * Returns: a strcmp()-style sort value comparing @app1 to @app2
+ * Since: 43
+ */
+gint
+gs_utils_app_sort_match_value (GsApp    *app1,
+                               GsApp    *app2,
+                               gpointer  user_data)
+{
+	return gs_app_get_match_value (app2) - gs_app_get_match_value (app1);
+}
+
+/**
+ * gs_utils_app_sort_priority:
+ * @app1: a #GsApp
+ * @app2: another #GsApp
+ * @user_data: data passed to the sort function
+ *
+ * Comparison function to sort apps in increasing order of their priority
+ * (#GsApp:priority).
+ *
+ * This is suitable for passing to gs_app_list_sort().
+ *
+ * Returns: a strcmp()-style sort value comparing @app1 to @app2
+ * Since: 43
+ */
+gint
+gs_utils_app_sort_priority (GsApp    *app1,
+                            GsApp    *app2,
+                            gpointer  user_data)
+{
+	return gs_app_compare_priority (app1, app2);
+}
diff --git a/lib/gs-utils.h b/lib/gs-utils.h
new file mode 100644
index 0000000..855e984
--- /dev/null
+++ b/lib/gs-utils.h
@@ -0,0 +1,155 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2013-2016 Richard Hughes <richard@hughsie.com>
+ * Copyright (C) 2018 Kalev Lember <klember@redhat.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <gio/gdesktopappinfo.h>
+#include <gtk/gtk.h>
+
+#include "gs-app.h"
+
+G_BEGIN_DECLS
+
+/**
+ * GsUtilsCacheFlags:
+ * @GS_UTILS_CACHE_FLAG_NONE:		No flags set
+ * @GS_UTILS_CACHE_FLAG_WRITEABLE:	A writable directory is required
+ * @GS_UTILS_CACHE_FLAG_USE_HASH:	Prefix a hash to the filename
+ * @GS_UTILS_CACHE_FLAG_ENSURE_EMPTY:	Clear existing cached items
+ * @GS_UTILS_CACHE_FLAG_CREATE_DIRECTORY:	Create the cache directory (Since: 40)
+ *
+ * The cache flags.
+ **/
+typedef enum {
+	GS_UTILS_CACHE_FLAG_NONE		= 0,
+	GS_UTILS_CACHE_FLAG_WRITEABLE		= 1 << 0,
+	GS_UTILS_CACHE_FLAG_USE_HASH		= 1 << 1,
+	GS_UTILS_CACHE_FLAG_ENSURE_EMPTY	= 1 << 2,
+	GS_UTILS_CACHE_FLAG_CREATE_DIRECTORY	= 1 << 3,
+	GS_UTILS_CACHE_FLAG_LAST  /*< skip >*/
+} GsUtilsCacheFlags;
+
+guint64		 gs_utils_get_file_age		(GFile		*file);
+gchar		*gs_utils_get_content_type	(GFile		*file,
+						 GCancellable	*cancellable,
+						 GError		**error);
+gboolean	 gs_utils_symlink		(const gchar	*target,
+						 const gchar	*linkpath,
+						 GError		**error);
+gboolean	 gs_utils_unlink		(const gchar	*filename,
+						 GError		**error);
+gboolean	 gs_mkdir_parent		(const gchar	*path,
+						 GError		**error);
+gchar		*gs_utils_get_cache_filename	(const gchar	*kind,
+						 const gchar	*resource,
+						 GsUtilsCacheFlags flags,
+						 GError		**error);
+gchar		*gs_utils_get_user_hash		(GError		**error);
+GPermission	*gs_utils_get_permission	(const gchar	*id,
+						 GCancellable	*cancellable,
+						 GError		**error);
+void		 gs_utils_get_permission_async	(const gchar		*id,
+						 GCancellable		*cancellable,
+						 GAsyncReadyCallback	 callback,
+						 gpointer		 user_data);
+GPermission	*gs_utils_get_permission_finish	(GAsyncResult	*result,
+						 GError		**error);
+gboolean	 gs_utils_strv_fnmatch		(gchar		**strv,
+						 const gchar	*str);
+gchar           *gs_utils_sort_key		(const gchar    *str);
+gint             gs_utils_sort_strcmp		(const gchar    *str1,
+						 const gchar	*str2);
+GDesktopAppInfo *gs_utils_get_desktop_app_info	(const gchar	*id);
+gboolean	 gs_utils_rmtree		(const gchar	*directory,
+						 GError		**error);
+gint		 gs_utils_get_wilson_rating	(guint64	 star1,
+						 guint64	 star2,
+						 guint64	 star3,
+						 guint64	 star4,
+						 guint64	 star5);
+void		 gs_utils_error_add_app_id	(GError		**error,
+						 GsApp		*app);
+void		 gs_utils_error_add_origin_id	(GError		**error,
+						 GsApp		*origin);
+gchar		*gs_utils_error_strip_app_id	(GError		*error);
+gchar		*gs_utils_error_strip_origin_id	(GError		*error);
+gboolean	 gs_utils_error_convert_gio	(GError		**perror);
+gboolean	 gs_utils_error_convert_gresolver (GError	**perror);
+gboolean	 gs_utils_error_convert_gdbus	(GError		**perror);
+gboolean	 gs_utils_error_convert_gdk_pixbuf(GError	**perror);
+gboolean	 gs_utils_error_convert_appstream (GError	**perror);
+
+gchar		*gs_utils_get_url_scheme	(const gchar	*url);
+gchar		*gs_utils_get_url_path		(const gchar	*url);
+const gchar	*gs_user_agent			(void);
+void		 gs_utils_append_key_value	(GString	*str,
+						 gsize		 align_len,
+						 const gchar	*key,
+						 const gchar	*value);
+guint		 gs_utils_get_memory_total	(void);
+gboolean	 gs_utils_parse_evr		(const gchar	 *evr,
+						 gchar		**out_epoch,
+						 gchar		**out_version,
+						 gchar		**out_release);
+void		 gs_utils_set_online_updates_timestamp (GSettings *settings);
+
+gchar		*gs_utils_unique_id_compat_convert	(const gchar	*data_id);
+
+gchar		*gs_utils_build_unique_id	(AsComponentScope scope,
+						 AsBundleKind bundle_kind,
+						 const gchar *origin,
+						 const gchar *cid,
+						 const gchar *branch);
+
+void		 gs_utils_pixbuf_blur		(GdkPixbuf	*src,
+						 guint		radius,
+						 guint		iterations);
+
+/**
+ * GsFileSizeIncludeFunc:
+ * @filename: file name to check
+ * @file_kind: the file kind, one of #GFileTest enums
+ * @user_data: a user data passed to the gs_utils_get_file_size()
+ *
+ * Check whether include the @filename in the size calculation.
+ * The @filename is a relative path to the file name passed to
+ * the #GsFileSizeIncludeFunc.
+ *
+ * Returns: Whether to include the @filename in the size calculation
+ *
+ * Since: 41
+ **/
+typedef gboolean (*GsFileSizeIncludeFunc)	(const gchar		*filename,
+						 GFileTest		 file_kind,
+						 gpointer		 user_data);
+
+guint64		 gs_utils_get_file_size		(const gchar		*filename,
+						 GsFileSizeIncludeFunc	 include_func,
+						 gpointer		 user_data,
+						 GCancellable		*cancellable);
+gchar *		 gs_utils_get_file_etag		(GFile			*file,
+						 GDateTime		**last_modified_date_out,
+						 GCancellable		*cancellable);
+gboolean	 gs_utils_set_file_etag		(GFile			*file,
+						 const gchar		*etag,
+						 GCancellable		*cancellable);
+
+gchar		*gs_utils_get_upgrade_background (const gchar		*version);
+
+gint		 gs_utils_app_sort_name		(GsApp			*app1,
+						 GsApp			*app2,
+						 gpointer		 user_data);
+gint		 gs_utils_app_sort_match_value	(GsApp			*app1,
+						 GsApp			*app2,
+						 gpointer		 user_data);
+gint		 gs_utils_app_sort_priority	(GsApp			*app1,
+						 GsApp			*app2,
+						 gpointer		 user_data);
+
+G_END_DECLS
diff --git a/lib/gs-worker-thread.c b/lib/gs-worker-thread.c
new file mode 100644
index 0000000..6e6686d
--- /dev/null
+++ b/lib/gs-worker-thread.c
@@ -0,0 +1,425 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+/**
+ * SECTION:gs-worker-thread
+ * @short_description: A worker thread which executes queued #GTasks until stopped
+ *
+ * #GsWorkerThread is a thread-safe wrapper around a #GTask queue and a single
+ * worker thread which executes tasks on that queue.
+ *
+ * Tasks can be added to the queue using gs_worker_thread_queue(). The worker
+ * thread (which is created when #GsWorkerThread is constructed) will execute
+ * them in (priority, queue order) order. Each #GTaskThreadFunc is responsible
+ * for calling `g_task_return_*()` on its #GTask to complete that task.
+ *
+ * The priority passed to gs_worker_thread_queue() will be used to adjust the
+ * worker thread’s I/O priority (using `ioprio_set()`) when executing that task.
+ *
+ * It is intended that gs_worker_thread_queue() is an alternative to using
+ * g_task_run_in_thread(). g_task_run_in_thread() queues tasks into a single
+ * process-wide thread pool, so they are mixed in with other tasks, and it can
+ * become hard to ensure the thread pool isn’t overwhelmed and that tasks are
+ * executed in the right order.
+ *
+ * The worker thread will continue executing tasks until
+ * gs_worker_thread_shutdown_async() is called. This must be called before the
+ * final reference to the #GsWorkerThread is dropped.
+ *
+ * Since: 42
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <glib-object.h>
+
+#include "gs-ioprio.h"
+#include "gs-worker-thread.h"
+
+typedef enum {
+	GS_WORKER_THREAD_STATE_RUNNING = 0,
+	GS_WORKER_THREAD_STATE_SHUTTING_DOWN = 1,
+	GS_WORKER_THREAD_STATE_SHUT_DOWN = 2,
+} GsWorkerThreadState;
+
+struct _GsWorkerThread
+{
+	GObject			 parent;
+
+	gchar			*name;  /* (nullable) (owned) */
+
+	GsWorkerThreadState	 worker_state;  /* (atomic) */
+	GMainContext		*worker_context;  /* (owned); may be NULL before setup or after shutdown */
+	GThread			*worker_thread;  /* (atomic); may be NULL before setup or after shutdown */
+};
+
+typedef enum {
+	PROP_NAME = 1,
+} GsWorkerThreadProperty;
+
+static GParamSpec *props[PROP_NAME + 1] = { NULL, };
+
+G_DEFINE_TYPE (GsWorkerThread, gs_worker_thread, G_TYPE_OBJECT)
+
+static void
+gs_worker_thread_get_property (GObject    *object,
+                               guint       prop_id,
+                               GValue     *value,
+                               GParamSpec *pspec)
+{
+	GsWorkerThread *self = GS_WORKER_THREAD (object);
+
+	switch ((GsWorkerThreadProperty) prop_id) {
+	case PROP_NAME:
+		g_value_set_string (value, self->name);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_worker_thread_set_property (GObject      *object,
+                               guint         prop_id,
+                               const GValue *value,
+                               GParamSpec   *pspec)
+{
+	GsWorkerThread *self = GS_WORKER_THREAD (object);
+
+	switch ((GsWorkerThreadProperty) prop_id) {
+	case PROP_NAME:
+		/* Construct only */
+		g_assert (self->name == NULL);
+		self->name = g_value_dup_string (value);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+		break;
+	}
+}
+
+static void
+gs_worker_thread_dispose (GObject *object)
+{
+	GsWorkerThread *self = GS_WORKER_THREAD (object);
+
+	/* Should have stopped by now. */
+	g_assert (self->worker_thread == NULL);
+
+	g_clear_pointer (&self->name, g_free);
+	g_clear_pointer (&self->worker_context, g_main_context_unref);
+
+	G_OBJECT_CLASS (gs_worker_thread_parent_class)->dispose (object);
+}
+
+static gpointer thread_cb (gpointer data);
+
+static void
+gs_worker_thread_constructed (GObject *object)
+{
+	GsWorkerThread *self = GS_WORKER_THREAD (object);
+
+	G_OBJECT_CLASS (gs_worker_thread_parent_class)->constructed (object);
+
+	/* Start up a worker thread and its #GMainContext. The worker will run
+	 * and process events on @worker_context until @worker_state changes
+	 * from %GS_WORKER_THREAD_STATE_RUNNING. */
+	self->worker_state = GS_WORKER_THREAD_STATE_RUNNING;
+	self->worker_context = g_main_context_new ();
+	self->worker_thread = g_thread_new (self->name, thread_cb, self);
+}
+
+static void
+gs_worker_thread_class_init (GsWorkerThreadClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+	object_class->constructed = gs_worker_thread_constructed;
+	object_class->get_property = gs_worker_thread_get_property;
+	object_class->set_property = gs_worker_thread_set_property;
+	object_class->dispose = gs_worker_thread_dispose;
+
+	/**
+	 * GsWorkerThread:name: (not nullable):
+	 *
+	 * Name for the worker thread to use in debug output. This must be set.
+	 *
+	 * Since: 42
+	 */
+	props[PROP_NAME] =
+		g_param_spec_string ("name",
+				     "Name",
+				     "Name for the worker thread to use in debug output.",
+				     NULL,
+				     G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
+
+	g_object_class_install_properties (object_class, G_N_ELEMENTS (props), props);
+}
+
+static gpointer
+thread_cb (gpointer data)
+{
+	GsWorkerThread *self = GS_WORKER_THREAD (data);
+	g_autoptr(GMainContextPusher) pusher = g_main_context_pusher_new (self->worker_context);
+
+	while (g_atomic_int_get (&self->worker_state) != GS_WORKER_THREAD_STATE_SHUT_DOWN)
+		g_main_context_iteration (self->worker_context, TRUE);
+
+	return NULL;
+}
+
+static void
+gs_worker_thread_init (GsWorkerThread *self)
+{
+}
+
+/**
+ * gs_worker_thread_new:
+ * @name: (not nullable): name for the worker thread
+ *
+ * Create and start a new #GsWorkerThread.
+ *
+ * @name will be used to set the thread name and in debug output.
+ *
+ * Returns: (transfer full): a new #GsWorkerThread
+ * Since: 42
+ */
+GsWorkerThread *
+gs_worker_thread_new (const gchar *name)
+{
+	g_return_val_if_fail (name != NULL, NULL);
+
+	return g_object_new (GS_TYPE_WORKER_THREAD,
+			     "name", name,
+			     NULL);
+}
+
+/* Essentially a wrapper around these elements to avoid the caller having to
+ * return `G_SOURCE_REMOVE` from their `work_func` every time. */
+typedef struct {
+	GTaskThreadFunc work_func;
+	GTask *task;  /* (owned) */
+	gint priority;
+} WorkData;
+
+static void
+work_data_free (WorkData *data)
+{
+	g_clear_object (&data->task);
+	g_free (data);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (WorkData, work_data_free)
+
+static gboolean
+work_run_cb (gpointer _data)
+{
+	WorkData *data = _data;
+	GTask *task = data->task;
+	gpointer source_object = g_task_get_source_object (task);
+	gpointer task_data = g_task_get_task_data (task);
+	GCancellable *cancellable = g_task_get_cancellable (task);
+
+	/* Set the I/O priority of the thread to match the priority of the
+	 * task. */
+	gs_ioprio_set (data->priority);
+
+	data->work_func (task, source_object, task_data, cancellable);
+
+	return G_SOURCE_REMOVE;
+}
+
+/**
+ * gs_worker_thread_queue:
+ * @self: a #GsWorkerThread
+ * @priority: (default G_PRIORITY_DEFAULT): priority to queue the task at,
+ *   typically #G_PRIORITY_DEFAULT
+ * @work_func: (not nullable): function to run the task
+ * @task: (transfer full) (not nullable): the #GTask containing context data to
+ *   pass to @work_func
+ *
+ * Queue @task to be run in the worker thread at the given @priority.
+ *
+ * This function takes ownership of @task.
+ *
+ * @priority sets the order of the task in the queue, and also affects the I/O
+ * priority of the worker thread when the task is executed — high priorities
+ * result in a high I/O priority, low priorities result in an idle I/O priority,
+ * as per `ioprio_set()`.
+ *
+ * When the task is run, @work_func will be executed and passed @task and the
+ * source object, task data and cancellable set on @task.
+ *
+ * @work_func is responsible for calling `g_task_return_*()` on @task once the
+ * task is complete.
+ *
+ * If a task is cancelled using its #GCancellable after it’s queued to the
+ * #GsWorkerThread, @work_func will still be executed. @work_func is responsible
+ * for checking whether the #GCancellable has been cancelled.
+ *
+ * It is an error to call this function after gs_worker_thread_shutdown_async()
+ * has called.
+ *
+ * Since: 42
+ */
+void
+gs_worker_thread_queue (GsWorkerThread  *self,
+                        gint             priority,
+                        GTaskThreadFunc  work_func,
+                        GTask           *task)
+{
+	g_autoptr(WorkData) data = NULL;
+
+	g_return_if_fail (GS_IS_WORKER_THREAD (self));
+	g_return_if_fail (work_func != NULL);
+	g_return_if_fail (G_IS_TASK (task));
+
+	g_assert (g_atomic_int_get (&self->worker_state) == GS_WORKER_THREAD_STATE_RUNNING ||
+		  g_task_get_source_tag (task) == gs_worker_thread_shutdown_async);
+
+	data = g_new0 (WorkData, 1);
+	data->work_func = work_func;
+	data->task = g_steal_pointer (&task);
+	data->priority = priority;
+
+	g_main_context_invoke_full (self->worker_context, priority,
+				    work_run_cb, g_steal_pointer (&data), (GDestroyNotify) work_data_free);
+}
+
+/**
+ * gs_worker_thread_is_in_worker_context:
+ * @self: a #GsWorkerThread
+ *
+ * Returns whether the calling thread is the worker thread.
+ *
+ * This is intended to be used as a precondition check to ensure that worker
+ * code is not accidentally run from the wrong thread.
+ *
+ * |[
+ * static void
+ * do_work (MyPlugin *self)
+ * {
+ *   g_assert (gs_worker_thread_is_in_worker_context (self->worker_thread));
+ *
+ *   // do some work
+ * }
+ * ]|
+ *
+ * Returns: %TRUE if running in the worker context, %FALSE otherwise
+ * Since: 42
+ */
+gboolean
+gs_worker_thread_is_in_worker_context (GsWorkerThread *self)
+{
+	return g_main_context_is_owner (self->worker_context);
+}
+
+static void shutdown_cb (GTask        *task,
+                         gpointer      source_object,
+                         gpointer      task_data,
+                         GCancellable *cancellable);
+
+/**
+ * gs_worker_thread_shutdown_async:
+ * @self: a #GsWorkerThread
+ * @cancellable: (nullable): a #GCancellable, or %NULL
+ * @callback: callback for once the asynchronous operation is complete
+ * @user_data: data to pass to @callback
+ *
+ * Shut down the worker thread.
+ *
+ * The thread will finish processing whatever task it’s currently processing
+ * (if any), will return %G_IO_ERROR_CANCELLED for all remaining queued
+ * tasks, and will then join the main process.
+ *
+ * This is a no-op if called subsequently.
+ *
+ * Since: 42
+ */
+void
+gs_worker_thread_shutdown_async (GsWorkerThread      *self,
+                                 GCancellable        *cancellable,
+                                 GAsyncReadyCallback  callback,
+                                 gpointer             user_data)
+{
+	g_autoptr(GTask) task = NULL;
+
+	g_return_if_fail (GS_IS_WORKER_THREAD (self));
+	g_return_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable));
+
+	task = g_task_new (self, cancellable, callback, user_data);
+	g_task_set_source_tag (task, gs_worker_thread_shutdown_async);
+
+	/* Already called? */
+	if (g_atomic_int_get (&self->worker_state) != GS_WORKER_THREAD_STATE_RUNNING) {
+		g_task_return_boolean (task, TRUE);
+		return;
+	}
+
+	/* Signal the worker thread to stop processing tasks. */
+	g_atomic_int_set (&self->worker_state, GS_WORKER_THREAD_STATE_SHUTTING_DOWN);
+	gs_worker_thread_queue (self, G_MAXINT  /* lowest priority */,
+				shutdown_cb, g_steal_pointer (&task));
+}
+
+static void
+shutdown_cb (GTask        *task,
+             gpointer      source_object,
+             gpointer      task_data,
+             GCancellable *cancellable)
+{
+	GsWorkerThread *self = GS_WORKER_THREAD (source_object);
+	gboolean updated_state;
+
+	updated_state = g_atomic_int_compare_and_exchange (&self->worker_state,
+							   GS_WORKER_THREAD_STATE_SHUTTING_DOWN,
+							   GS_WORKER_THREAD_STATE_SHUT_DOWN);
+	g_assert (updated_state);
+
+	/* Tidy up. We can’t join the thread here as this function is executing
+	 * within the thread and that would deadlock. */
+	g_clear_pointer (&self->worker_context, g_main_context_unref);
+
+	g_task_return_boolean (task, TRUE);
+}
+
+/**
+ * gs_worker_thread_shutdown_finish:
+ * @self: a #GsWorkerThread
+ * @result: a #GAsyncResult
+ * @error: return location for a #GError, or %NULL
+ *
+ * Finish an asynchronous shutdown operation started with
+ * gs_worker_thread_shutdown_async();
+ *
+ * Returns: %TRUE on success, %FALSE otherwise
+ * Since: 42
+ */
+gboolean
+gs_worker_thread_shutdown_finish (GsWorkerThread  *self,
+                                  GAsyncResult    *result,
+                                  GError         **error)
+{
+	gboolean success;
+
+	g_return_val_if_fail (GS_IS_WORKER_THREAD (self), FALSE);
+	g_return_val_if_fail (g_async_result_is_tagged (result, gs_worker_thread_shutdown_async), FALSE);
+	g_return_val_if_fail (g_task_is_valid (result, self), FALSE);
+	g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
+
+	success = g_task_propagate_boolean (G_TASK (result), error);
+
+	if (success)
+		g_thread_join (g_steal_pointer (&self->worker_thread));
+
+	return success;
+}
diff --git a/lib/gs-worker-thread.h b/lib/gs-worker-thread.h
new file mode 100644
index 0000000..36b28df
--- /dev/null
+++ b/lib/gs-worker-thread.h
@@ -0,0 +1,41 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Endless OS Foundation LLC
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#pragma once
+
+#include <glib.h>
+#include <glib-object.h>
+#include <gio/gio.h>
+
+G_BEGIN_DECLS
+
+#define GS_TYPE_WORKER_THREAD (gs_worker_thread_get_type ())
+
+G_DECLARE_FINAL_TYPE (GsWorkerThread, gs_worker_thread, GS, WORKER_THREAD, GObject)
+
+GsWorkerThread	*gs_worker_thread_new			(const gchar *name);
+
+void		 gs_worker_thread_queue			(GsWorkerThread  *self,
+							 gint             priority,
+							 GTaskThreadFunc  work_func,
+							 GTask           *task);
+
+gboolean	 gs_worker_thread_is_in_worker_context	(GsWorkerThread *self);
+
+void		 gs_worker_thread_shutdown_async	(GsWorkerThread      *self,
+							 GCancellable        *cancellable,
+							 GAsyncReadyCallback  callback,
+							 gpointer             user_data);
+
+gboolean	 gs_worker_thread_shutdown_finish	(GsWorkerThread  *self,
+							 GAsyncResult    *result,
+							 GError         **error);
+
+G_END_DECLS
diff --git a/lib/meson.build b/lib/meson.build
new file mode 100644
index 0000000..d591bca
--- /dev/null
+++ b/lib/meson.build
@@ -0,0 +1,205 @@
+cargs = ['-DG_LOG_DOMAIN="Gs"']
+cargs += ['-DLOCALPLUGINDIR=""']
+
+libgnomesoftware_public_headers = [
+  'gnome-software.h',
+  'gs-app.h',
+  'gs-app-collation.h',
+  'gs-app-list.h',
+  'gs-app-permissions.h',
+  'gs-app-query.h',
+  'gs-appstream.h',
+  'gs-category.h',
+  'gs-category-manager.h',
+  'gs-desktop-data.h',
+  'gs-download-utils.h',
+  'gs-external-appstream-utils.h',
+  'gs-icon.h',
+  'gs-ioprio.h',
+  'gs-key-colors.h',
+  'gs-metered.h',
+  'gs-odrs-provider.h',
+  'gs-os-release.h',
+  'gs-plugin.h',
+  'gs-plugin-event.h',
+  'gs-plugin-helpers.h',
+  'gs-plugin-job.h',
+  'gs-plugin-job-list-apps.h',
+  'gs-plugin-job-list-categories.h',
+  'gs-plugin-job-list-distro-upgrades.h',
+  'gs-plugin-job-manage-repository.h',
+  'gs-plugin-job-refine.h',
+  'gs-plugin-job-refresh-metadata.h',
+  'gs-plugin-loader.h',
+  'gs-plugin-loader-sync.h',
+  'gs-plugin-types.h',
+  'gs-plugin-vfuncs.h',
+  'gs-remote-icon.h',
+  'gs-test.h',
+  'gs-utils.h',
+  'gs-worker-thread.h',
+]
+
+install_headers(libgnomesoftware_public_headers,
+  subdir : 'gnome-software'
+)
+
+librarydeps = [
+  appstream,
+  gio_unix,
+  glib,
+  gmodule,
+  gtk,
+  json_glib,
+  libm,
+  libsoup,
+  libsysprof_capture_dep,
+  libxmlb,
+]
+
+if get_option('mogwai')
+  librarydeps += mogwai_schedule_client
+endif
+
+if get_option('polkit')
+  librarydeps += polkit
+endif
+
+gs_build_ident_h = vcs_tag(
+     fallback: meson.project_version(),
+        input: 'gs-build-ident.h.in',
+       output: 'gs-build-ident.h',
+)
+
+libgnomesoftware_enums = gnome.mkenums_simple('gs-enums',
+  sources : libgnomesoftware_public_headers,
+  install_header : true,
+  install_dir : join_paths(get_option('includedir'), 'gnome-software'),
+)
+
+libgnomesoftware_include_directories = [
+  include_directories('..'),
+]
+
+libgnomesoftware = library(
+  'gnomesoftware',
+  sources : [
+    'gs-app.c',
+    'gs-app-list.c',
+    'gs-app-permissions.c',
+    'gs-app-query.c',
+    'gs-appstream.c',
+    'gs-category.c',
+    'gs-category-manager.c',
+    'gs-debug.c',
+    'gs-desktop-data.c',
+    'gs-download-utils.c',
+    'gs-external-appstream-utils.c',
+    'gs-fedora-third-party.c',
+    'gs-icon.c',
+    'gs-ioprio.c',
+    'gs-ioprio.h',
+    'gs-key-colors.c',
+    'gs-metered.c',
+    'gs-odrs-provider.c',
+    'gs-os-release.c',
+    'gs-plugin.c',
+    'gs-plugin-event.c',
+    'gs-plugin-helpers.c',
+    'gs-plugin-job.c',
+    'gs-plugin-job-list-apps.c',
+    'gs-plugin-job-list-categories.c',
+    'gs-plugin-job-list-distro-upgrades.c',
+    'gs-plugin-job-manage-repository.c',
+    'gs-plugin-job-refine.c',
+    'gs-plugin-job-refresh-metadata.c',
+    'gs-plugin-loader.c',
+    'gs-plugin-loader-sync.c',
+    'gs-remote-icon.c',
+    'gs-test.c',
+    'gs-utils.c',
+    'gs-worker-thread.c',
+  ] + libgnomesoftware_enums + [gs_build_ident_h],
+  soversion: gs_plugin_api_version,
+  include_directories : libgnomesoftware_include_directories,
+  dependencies : librarydeps,
+  c_args : cargs,
+  install: true,
+  install_dir: gs_private_libdir,
+)
+
+libgnomesoftware_dep = declare_dependency(link_with : libgnomesoftware,
+  sources : libgnomesoftware_enums,
+  include_directories : libgnomesoftware_include_directories,
+  dependencies: librarydeps,
+)
+
+pkg = import('pkgconfig')
+
+pkg.generate(
+    libgnomesoftware,
+    description : 'GNOME Software is a software center for GNOME',
+    filebase : 'gnome-software',
+    name : 'gnome-software',
+    subdirs : 'gnome-software',
+    variables : [
+      'gs_private_libdir=${libdir}/gnome-software',
+      'plugindir=${gs_private_libdir}/plugins-' + gs_plugin_api_version,
+      'soupapiversion=' + libsoupapiversion,
+    ],
+    install_dir : join_paths(get_option('prefix'), get_option('libdir'), 'pkgconfig'),  # or it defaults to gs_private_libdir, which is wrong
+)
+
+executable(
+  'gnome-software-cmd',
+  sources : [
+    'gs-cmd.c',
+  ],
+  include_directories : [
+    include_directories('..'),
+  ],
+  dependencies : [
+    appstream,
+    gio_unix,
+    glib,
+    gmodule,
+    gtk,
+    json_glib,
+    libgnomesoftware_dep,
+    libm,
+    libsoup,
+  ],
+  c_args : cargs,
+  install : true,
+  install_dir : get_option('libexecdir'),
+  install_rpath : gs_private_libdir,
+)
+
+if get_option('tests')
+  cargs += ['-DTESTDATADIR="' + join_paths(meson.current_source_dir(), '..', 'data') + '"']
+  e = executable(
+    'gs-self-test',
+    compiled_schemas,
+    sources : [
+      'gs-self-test.c'
+    ],
+    include_directories : [
+      include_directories('..'),
+    ],
+    dependencies : [
+      appstream,
+      gio_unix,
+      glib,
+      gmodule,
+      gtk,
+      json_glib,
+      libgnomesoftware_dep,
+      libm,
+      libsoup
+    ],
+    c_args : cargs
+  )
+  test('gs-self-test-lib', e, suite: ['lib'], env: test_env, timeout : 120)
+endif
+
+subdir('tools')
diff --git a/lib/tools/meson.build b/lib/tools/meson.build
new file mode 100644
index 0000000..6844775
--- /dev/null
+++ b/lib/tools/meson.build
@@ -0,0 +1,24 @@
+# Test program to profile performance of the key-colors functions
+executable(
+  'profile-key-colors',
+  sources : [
+    'profile-key-colors.c',
+    '../gs-key-colors.c',
+    '../gs-key-colors.h',
+  ],
+  include_directories : [
+    include_directories('..'),
+    include_directories('../..'),
+  ],
+  dependencies : [
+    glib,
+    gtk,
+    gdk_pixbuf,
+    libm,
+  ],
+  c_args : [
+    '-Wall',
+    '-Wextra',
+  ],
+  install: false,
+)
diff --git a/lib/tools/profile-key-colors.c b/lib/tools/profile-key-colors.c
new file mode 100644
index 0000000..44df6a4
--- /dev/null
+++ b/lib/tools/profile-key-colors.c
@@ -0,0 +1,175 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ * vi:set noexpandtab tabstop=8 shiftwidth=8:
+ *
+ * Copyright (C) 2021 Endless OS Foundation LLC
+ *
+ * Authors:
+ *  - Philip Withnall <pwithnall@endlessos.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <glib.h>
+#include <gdk-pixbuf/gdk-pixbuf.h>
+#include <gdk/gdk.h>
+#include <locale.h>
+#include <math.h>
+
+#include "gs-key-colors.h"
+
+/* Test program which can be used to check the output and performance of the
+ * gs_calculate_key_colors() function. It is linked against libgnomesoftware, so
+ * will use the function implementation from there. It outputs a HTML page which
+ * lists each icon from the flathub appstream data in your home directory, along
+ * with its extracted key colors and how long extraction took. */
+
+static void
+print_colours (GString *html_output,
+               GArray  *colours)
+{
+	g_string_append_printf (html_output, "<table class='colour-swatch'><tr>");
+	for (guint i = 0; i < colours->len; i++) {
+		GdkRGBA *rgba = &g_array_index (colours, GdkRGBA, i);
+
+		g_string_append_printf (html_output,
+					"<td style='background-color: rgb(%u, %u, %u)'></td>",
+					(guint) (rgba->red * 255),
+					(guint) (rgba->green * 255),
+					(guint) (rgba->blue * 255));
+
+		if (i % 3 == 2)
+			g_string_append (html_output, "</tr><tr>");
+	}
+	g_string_append_printf (html_output, "</tr></table>");
+}
+
+static void
+print_summary_statistics (GString *html_output,
+                          GArray  *durations  /* (element-type gint64) */)
+{
+	gint64 sum = 0, min = G_MAXINT64, max = G_MININT64;
+	guint n_measurements = durations->len;
+	gint64 mean, stddev;
+	gint64 sum_of_square_deviations = 0;
+
+	for (guint i = 0; i < durations->len; i++) {
+		gint64 duration = g_array_index (durations, gint64, i);
+		sum += duration;
+		min = MIN (min, duration);
+		max = MAX (max, duration);
+	}
+
+	mean = sum / n_measurements;
+
+	for (guint i = 0; i < durations->len; i++) {
+		gint64 duration = g_array_index (durations, gint64, i);
+		gint64 diff = duration - mean;
+		sum_of_square_deviations += diff * diff;
+	}
+
+	stddev = sqrt (sum_of_square_deviations / n_measurements);
+
+	g_string_append_printf (html_output,
+				"[%" G_GINT64_FORMAT ", %" G_GINT64_FORMAT "]μs, mean %" G_GINT64_FORMAT "±%" G_GINT64_FORMAT "μs, n = %u",
+				min, max, mean, stddev, n_measurements);
+}
+
+int
+main (void)
+{
+	const gchar *icons_subdir = ".local/share/flatpak/appstream/flathub/x86_64/active/icons/128x128";
+	g_autofree gchar *icons_dir = g_build_filename (g_get_home_dir (), icons_subdir, NULL);
+	g_autoptr(GDir) dir = NULL;
+	const gchar *entry;
+	g_autoptr(GPtrArray) filenames = g_ptr_array_new_with_free_func (g_free);
+	g_autoptr(GPtrArray) pixbufs = g_ptr_array_new_with_free_func (g_object_unref);
+	g_autoptr(GString) html_output = g_string_new ("");
+	g_autoptr(GArray) durations = g_array_new (FALSE, FALSE, sizeof (gint64));
+
+	setlocale (LC_ALL, "");
+
+	/* Load pixbufs from the icons directory. */
+	dir = g_dir_open (icons_dir, 0, NULL);
+	if (dir == NULL)
+		return 1;
+
+	while ((entry = g_dir_read_name (dir)) != NULL) {
+		g_autofree gchar *filename = g_build_filename (icons_dir, entry, NULL);
+		g_autoptr(GdkPixbuf) pixbuf = gdk_pixbuf_new_from_file (filename, NULL);
+
+		if (pixbuf == NULL)
+			continue;
+
+		g_ptr_array_add (filenames, g_steal_pointer (&filename));
+		g_ptr_array_add (pixbufs, g_steal_pointer (&pixbuf));
+	}
+
+	if (!pixbufs->len)
+		return 2;
+
+	/* Set up an output page */
+	g_string_append (html_output,
+			 "<!DOCTYPE html>\n"
+			 "<html>\n"
+			 "  <head>\n"
+			 "    <meta charset='UTF-8'>\n"
+			 "    <style>\n"
+			 "      #main-table, #main-table th, #main-table td { border: 1px solid black; border-collapse: collapse }\n"
+			 "      #main-table th, #main-table td { padding: 4px }\n"
+			 "      td.number { text-align: right }\n"
+			 "      table.colour-swatch td { width: 30px; height: 30px }\n"
+			 "      .faster { background-color: rgb(190, 236, 57) }\n"
+			 "      .slower { background-color: red }\n"
+			 "    </style>\n"
+			 "  </head>\n"
+			 "  <body>\n"
+			 "    <table id='main-table'>\n"
+			 "      <thead>\n"
+			 "        <tr>\n"
+			 "          <td>Filename</td>\n"
+			 "          <td>Icon</td>\n"
+			 "          <td>Code duration (μs)</td>\n"
+			 "          <td>Code colours</td>\n"
+			 "        </tr>\n"
+			 "      </thead>\n");
+
+	/* For each pixbuf, run both algorithms. */
+	for (guint i = 0; i < pixbufs->len; i++) {
+		GdkPixbuf *pixbuf = pixbufs->pdata[i];
+		const gchar *filename = filenames->pdata[i];
+		g_autofree gchar *basename = g_path_get_basename (filename);
+		g_autoptr(GArray) colours = NULL;
+		gint64 start_time, duration;
+
+		g_message ("Processing %u of %u, %s", i + 1, pixbufs->len, filename);
+
+		start_time = g_get_real_time ();
+		colours = gs_calculate_key_colors (pixbuf);
+		duration = g_get_real_time () - start_time;
+
+		g_string_append_printf (html_output,
+					"<tr>\n"
+					"<th>%s</th>\n"
+					"<td><img src='file:%s'></td>\n"
+					"<td class='number'>%" G_GINT64_FORMAT "</td>\n"
+					"<td>",
+					basename, filename, duration);
+		print_colours (html_output, colours);
+		g_string_append (html_output,
+				 "</td>\n"
+				 "</tr>\n");
+
+		g_array_append_val (durations, duration);
+	}
+
+	/* Summary statistics for the timings. */
+	g_string_append (html_output, "<tfoot><tr><td></td><td></td><td>");
+	print_summary_statistics (html_output, durations);
+	g_string_append (html_output, "</td><td></td></tr></tfoot>");
+
+	g_string_append (html_output, "</table></body></html>");
+
+	g_print ("%s\n", html_output->str);
+
+	return 0;
+}