1 files changed, 113 insertions, 0 deletions
diff --git a/remote/marionette/actors/MarionetteEventsParent.sys.mjs b/remote/marionette/actors/MarionetteEventsParent.sys.mjs
new file mode 100644
index 0000000000..c051fb2b1f
--- /dev/null
+++ b/remote/marionette/actors/MarionetteEventsParent.sys.mjs
@@ -0,0 +1,113 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  EventEmitter: "resource://gre/modules/EventEmitter.sys.mjs",
+
+  Log: "chrome://remote/content/shared/Log.sys.mjs",
+});
+
+ChromeUtils.defineLazyGetter(lazy, "logger", () =>
+  lazy.Log.get(lazy.Log.TYPES.MARIONETTE)
+);
+
+// Singleton to allow forwarding events to registered listeners.
+export const EventDispatcher = {
+  init() {
+    lazy.EventEmitter.decorate(this);
+  },
+};
+
+EventDispatcher.init();
+
+export class MarionetteEventsParent extends JSWindowActorParent {
+  async receiveMessage(msg) {
+    const { name, data } = msg;
+
+    let rv;
+    switch (name) {
+      case "MarionetteEventsChild:PageLoadEvent":
+        EventDispatcher.emit("page-load", data);
+        break;
+    }
+
+    return rv;
+  }
+}
+
+// Flag to check if the MarionetteEvents actors have already been registed.
+let eventsActorRegistered = false;
+
+/**
+ * Register Events actors to listen for page load events via EventDispatcher.
+ */
+function registerEventsActor() {
+  if (eventsActorRegistered) {
+    return;
+  }
+
+  try {
+    // Register the JSWindowActor pair for events as used by Marionette
+    ChromeUtils.registerWindowActor("MarionetteEvents", {
+      kind: "JSWindowActor",
+      parent: {
+        esModuleURI:
+          "chrome://remote/content/marionette/actors/MarionetteEventsParent.sys.mjs",
+      },
+      child: {
+        esModuleURI:
+          "chrome://remote/content/marionette/actors/MarionetteEventsChild.sys.mjs",
+        events: {
+          beforeunload: { capture: true },
+          DOMContentLoaded: { mozSystemGroup: true },
+          hashchange: { mozSystemGroup: true },
+          pagehide: { mozSystemGroup: true },
+          pageshow: { mozSystemGroup: true },
+          // popstate doesn't bubble, as such use capturing phase
+          popstate: { capture: true, mozSystemGroup: true },
+
+          click: {},
+          dblclick: {},
+          unload: { capture: true, createActor: false },
+        },
+      },
+
+      allFrames: true,
+      includeChrome: true,
+    });
+
+    eventsActorRegistered = true;
+  } catch (e) {
+    if (e.name === "NotSupportedError") {
+      lazy.logger.warn(`MarionetteEvents actor is already registered!`);
+    } else {
+      throw e;
+    }
+  }
+}
+
+/**
+ * Enable MarionetteEvents actors to start forwarding page load events from the
+ * child actor to the parent actor. Register the MarionetteEvents actor if necessary.
+ */
+export function enableEventsActor() {
+  // sharedData is replicated across processes and will be checked by
+  // MarionetteEventsChild before forward events to the parent actor.
+  Services.ppmm.sharedData.set("MARIONETTE_EVENTS_ENABLED", true);
+  // Request to immediately flush the data to the content processes to avoid races.
+  Services.ppmm.sharedData.flush();
+
+  registerEventsActor();
+}
+
+/**
+ * Disable MarionetteEvents actors to stop forwarding page load events from the
+ * child actor to the parent actor.
+ */
+export function disableEventsActor() {
+  Services.ppmm.sharedData.set("MARIONETTE_EVENTS_ENABLED", false);
+  Services.ppmm.sharedData.flush();
+}