1 files changed, 253 insertions, 0 deletions
diff --git a/devtools/server/actors/descriptors/tab.js b/devtools/server/actors/descriptors/tab.js
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+++ b/devtools/server/actors/descriptors/tab.js
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+/* 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/. */
+
+"use strict";
+
+/*
+ * Descriptor Actor that represents a Tab in the parent process. It
+ * launches a WindowGlobalTargetActor in the content process to do the real work and tunnels the
+ * data.
+ *
+ * See devtools/docs/backend/actor-hierarchy.md for more details.
+ */
+
+const { Actor } = require("resource://devtools/shared/protocol.js");
+const {
+  tabDescriptorSpec,
+} = require("resource://devtools/shared/specs/descriptors/tab.js");
+
+const {
+  connectToFrame,
+} = require("resource://devtools/server/connectors/frame-connector.js");
+const lazy = {};
+ChromeUtils.defineESModuleGetters(lazy, {
+  PlacesUtils: "resource://gre/modules/PlacesUtils.sys.mjs",
+});
+
+const { AppConstants } = ChromeUtils.importESModule(
+  "resource://gre/modules/AppConstants.sys.mjs"
+);
+const {
+  createBrowserElementSessionContext,
+} = require("resource://devtools/server/actors/watcher/session-context.js");
+
+loader.lazyRequireGetter(
+  this,
+  "WatcherActor",
+  "resource://devtools/server/actors/watcher.js",
+  true
+);
+
+/**
+ * Creates a target actor proxy for handling requests to a single browser frame.
+ * Both <xul:browser> and <iframe mozbrowser> are supported.
+ * This actor is a shim that connects to a WindowGlobalTargetActor in a remote browser process.
+ * All RDP packets get forwarded using the message manager.
+ *
+ * @param connection The main RDP connection.
+ * @param browser <xul:browser> or <iframe mozbrowser> element to connect to.
+ */
+class TabDescriptorActor extends Actor {
+  constructor(connection, browser) {
+    super(connection, tabDescriptorSpec);
+    this._browser = browser;
+  }
+
+  form() {
+    const form = {
+      actor: this.actorID,
+      browserId: this._browser.browserId,
+      browsingContextID:
+        this._browser && this._browser.browsingContext
+          ? this._browser.browsingContext.id
+          : null,
+      isZombieTab: this._isZombieTab(),
+      outerWindowID: this._getOuterWindowId(),
+      selected: this.selected,
+      title: this._getTitle(),
+      traits: {
+        // Supports the Watcher actor. Can be removed as part of Bug 1680280.
+        watcher: true,
+        supportsReloadDescriptor: true,
+      },
+      url: this._getUrl(),
+    };
+
+    return form;
+  }
+
+  _getTitle() {
+    // If the content already provides a title, use it.
+    if (this._browser.contentTitle) {
+      return this._browser.contentTitle;
+    }
+
+    // For zombie or lazy tabs (tab created, but content has not been loaded),
+    // try to retrieve the title from the XUL Tab itself.
+    // Note: this only works on Firefox desktop.
+    if (this._tabbrowser) {
+      const tab = this._tabbrowser.getTabForBrowser(this._browser);
+      if (tab) {
+        return tab.label;
+      }
+    }
+
+    // No title available.
+    return null;
+  }
+
+  _getUrl() {
+    if (!this._browser || !this._browser.browsingContext) {
+      return "";
+    }
+
+    const { browsingContext } = this._browser;
+    return browsingContext.currentWindowGlobal.documentURI.spec;
+  }
+
+  _getOuterWindowId() {
+    if (!this._browser || !this._browser.browsingContext) {
+      return "";
+    }
+
+    const { browsingContext } = this._browser;
+    return browsingContext.currentWindowGlobal.outerWindowId;
+  }
+
+  get selected() {
+    // getMostRecentBrowserWindow will find the appropriate window on Firefox
+    // Desktop and on GeckoView.
+    const topAppWindow = Services.wm.getMostRecentBrowserWindow();
+
+    const selectedBrowser = topAppWindow?.gBrowser?.selectedBrowser;
+    if (!selectedBrowser) {
+      // Note: gBrowser is not available on GeckoView.
+      // We should find another way to know if this browser is the selected
+      // browser. See Bug 1631020.
+      return false;
+    }
+
+    return this._browser === selectedBrowser;
+  }
+
+  async getTarget() {
+    if (!this.conn) {
+      return {
+        error: "tabDestroyed",
+        message: "Tab destroyed while performing a TabDescriptorActor update",
+      };
+    }
+
+    /* eslint-disable-next-line no-async-promise-executor */
+    return new Promise(async (resolve, reject) => {
+      const onDestroy = () => {
+        // Reject the update promise if the tab was destroyed while requesting an update
+        reject({
+          error: "tabDestroyed",
+          message: "Tab destroyed while performing a TabDescriptorActor update",
+        });
+
+        // Targets created from the TabDescriptor are not created via JSWindowActors and
+        // we need to notify the watcher manually about their destruction.
+        // TabDescriptor's targets are created via TabDescriptor.getTarget and are still using
+        // message manager instead of JSWindowActors.
+        if (this.watcher && this.targetActorForm) {
+          this.watcher.notifyTargetDestroyed(this.targetActorForm);
+        }
+      };
+
+      try {
+        // Check if the browser is still connected before calling connectToFrame
+        if (!this._browser.isConnected) {
+          onDestroy();
+          return;
+        }
+
+        const connectForm = await connectToFrame(
+          this.conn,
+          this._browser,
+          onDestroy
+        );
+        this.targetActorForm = connectForm;
+        resolve(connectForm);
+      } catch (e) {
+        reject({
+          error: "tabDestroyed",
+          message: "Tab destroyed while connecting to the frame",
+        });
+      }
+    });
+  }
+
+  /**
+   * Return a Watcher actor, allowing to keep track of targets which
+   * already exists or will be created. It also helps knowing when they
+   * are destroyed.
+   */
+  getWatcher(config) {
+    if (!this.watcher) {
+      this.watcher = new WatcherActor(
+        this.conn,
+        createBrowserElementSessionContext(this._browser, {
+          isServerTargetSwitchingEnabled: config.isServerTargetSwitchingEnabled,
+          isPopupDebuggingEnabled: config.isPopupDebuggingEnabled,
+        })
+      );
+      this.manage(this.watcher);
+    }
+    return this.watcher;
+  }
+
+  get _tabbrowser() {
+    if (this._browser && typeof this._browser.getTabBrowser == "function") {
+      return this._browser.getTabBrowser();
+    }
+    return null;
+  }
+
+  async getFavicon() {
+    if (!AppConstants.MOZ_PLACES) {
+      // PlacesUtils is not supported
+      return null;
+    }
+
+    try {
+      const { data } = await lazy.PlacesUtils.promiseFaviconData(
+        this._getUrl()
+      );
+      return data;
+    } catch (e) {
+      // Favicon unavailable for this url.
+      return null;
+    }
+  }
+
+  _isZombieTab() {
+    // Note: GeckoView doesn't support zombie tabs
+    const tabbrowser = this._tabbrowser;
+    const tab = tabbrowser ? tabbrowser.getTabForBrowser(this._browser) : null;
+    return tab?.hasAttribute && tab.hasAttribute("pending");
+  }
+
+  reloadDescriptor({ bypassCache }) {
+    if (!this._browser || !this._browser.browsingContext) {
+      return;
+    }
+
+    this._browser.browsingContext.reload(
+      bypassCache
+        ? Ci.nsIWebNavigation.LOAD_FLAGS_BYPASS_CACHE
+        : Ci.nsIWebNavigation.LOAD_FLAGS_NONE
+    );
+  }
+
+  destroy() {
+    this.emit("descriptor-destroyed");
+    this._browser = null;
+
+    super.destroy();
+  }
+}
+
+exports.TabDescriptorActor = TabDescriptorActor;