1 files changed, 289 insertions, 0 deletions
diff --git a/browser/components/newtab/aboutNewTabService.js b/browser/components/newtab/aboutNewTabService.js
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+++ b/browser/components/newtab/aboutNewTabService.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/.
+*/
+
+/* globals XPCOMUtils, NewTabPrefsProvider, Services,
+  Locale, UpdateUtils, NewTabRemoteResources
+*/
+"use strict";
+
+const {utils: Cu, interfaces: Ci} = Components;
+
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+Cu.import("resource://gre/modules/Services.jsm");
+
+XPCOMUtils.defineLazyModuleGetter(this, "UpdateUtils",
+                                  "resource://gre/modules/UpdateUtils.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "NewTabPrefsProvider",
+                                  "resource:///modules/NewTabPrefsProvider.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "Locale",
+                                  "resource://gre/modules/Locale.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "NewTabRemoteResources",
+                                  "resource:///modules/NewTabRemoteResources.jsm");
+
+const LOCAL_NEWTAB_URL = "chrome://browser/content/newtab/newTab.xhtml";
+
+const REMOTE_NEWTAB_PATH = "/newtab/v%VERSION%/%CHANNEL%/%LOCALE%/index.html";
+
+const ABOUT_URL = "about:newtab";
+
+// Pref that tells if remote newtab is enabled
+const PREF_REMOTE_ENABLED = "browser.newtabpage.remote";
+
+// Pref branch necesssary for testing
+const PREF_REMOTE_CS_TEST = "browser.newtabpage.remote.content-signing-test";
+
+// The preference that tells whether to match the OS locale
+const PREF_MATCH_OS_LOCALE = "intl.locale.matchOS";
+
+// The preference that tells what locale the user selected
+const PREF_SELECTED_LOCALE = "general.useragent.locale";
+
+// The preference that tells what remote mode is enabled.
+const PREF_REMOTE_MODE = "browser.newtabpage.remote.mode";
+
+// The preference that tells which remote version is expected.
+const PREF_REMOTE_VERSION = "browser.newtabpage.remote.version";
+
+const VALID_CHANNELS = new Set(["esr", "release", "beta", "aurora", "nightly"]);
+
+function AboutNewTabService() {
+  NewTabPrefsProvider.prefs.on(PREF_REMOTE_ENABLED, this._handleToggleEvent.bind(this));
+
+  this._updateRemoteMaybe = this._updateRemoteMaybe.bind(this);
+
+  // trigger remote change if needed, according to pref
+  this.toggleRemote(Services.prefs.getBoolPref(PREF_REMOTE_ENABLED));
+}
+
+/*
+ * A service that allows for the overriding, at runtime, of the newtab page's url.
+ * Additionally, the service manages pref state between a remote and local newtab page.
+ *
+ * There is tight coupling with browser/about/AboutRedirector.cpp.
+ *
+ * 1. Browser chrome access:
+ *
+ * When the user issues a command to open a new tab page, usually clicking a button
+ * in the browser chrome or using shortcut keys, the browser chrome code invokes the
+ * service to obtain the newtab URL. It then loads that URL in a new tab.
+ *
+ * When not overridden, the default URL emitted by the service is "about:newtab".
+ * When overridden, it returns the overriden URL.
+ *
+ * 2. Redirector Access:
+ *
+ * When the URL loaded is about:newtab, the default behavior, or when entered in the
+ * URL bar, the redirector is hit. The service is then called to return either of
+ * two URLs, a chrome or remote one, based on the browser.newtabpage.remote pref.
+ *
+ * NOTE: "about:newtab" will always result in a default newtab page, and never an overridden URL.
+ *
+ * Access patterns:
+ *
+ * The behavior is different when accessing the service via browser chrome or via redirector
+ * largely to maintain compatibility with expectations of add-on developers.
+ *
+ * Loading a chrome resource, or an about: URL in the redirector with either the
+ * LOAD_NORMAL or LOAD_REPLACE flags yield unexpected behaviors, so a roundtrip
+ * to the redirector from browser chrome is avoided.
+ */
+AboutNewTabService.prototype = {
+
+  _newTabURL: ABOUT_URL,
+  _remoteEnabled: false,
+  _remoteURL: null,
+  _overridden: false,
+
+  classID: Components.ID("{dfcd2adc-7867-4d3a-ba70-17501f208142}"),
+  QueryInterface: XPCOMUtils.generateQI([Ci.nsIAboutNewTabService]),
+  _xpcom_categories: [{
+    service: true
+  }],
+
+  _handleToggleEvent(prefName, stateEnabled, forceState) { // jshint unused:false
+    if (this.toggleRemote(stateEnabled, forceState)) {
+      Services.obs.notifyObservers(null, "newtab-url-changed", ABOUT_URL);
+    }
+  },
+
+  /**
+   * React to changes to the remote newtab pref.
+   *
+   * If browser.newtabpage.remote is true, this will change the default URL to the
+   * remote newtab page URL. If browser.newtabpage.remote is false, the default URL
+   * will be a local chrome URL.
+   *
+   * This will only act if there is a change of state and if not overridden.
+   *
+   * @returns {Boolean} Returns if there has been a state change
+   *
+   * @param {Boolean}   stateEnabled    remote state to set to
+   * @param {Boolean}   forceState      force state change
+   */
+  toggleRemote(stateEnabled, forceState) {
+
+    if (!forceState && (this._overriden || stateEnabled === this._remoteEnabled)) {
+      // exit there is no change of state
+      return false;
+    }
+
+    let csTest = Services.prefs.getBoolPref(PREF_REMOTE_CS_TEST);
+    if (stateEnabled) {
+      if (!csTest) {
+        this._remoteURL = this.generateRemoteURL();
+      } else {
+        this._remoteURL = this._newTabURL;
+      }
+      NewTabPrefsProvider.prefs.on(
+        PREF_SELECTED_LOCALE,
+        this._updateRemoteMaybe);
+      NewTabPrefsProvider.prefs.on(
+        PREF_MATCH_OS_LOCALE,
+        this._updateRemoteMaybe);
+      NewTabPrefsProvider.prefs.on(
+        PREF_REMOTE_MODE,
+        this._updateRemoteMaybe);
+      NewTabPrefsProvider.prefs.on(
+        PREF_REMOTE_VERSION,
+        this._updateRemoteMaybe);
+      this._remoteEnabled = true;
+    } else {
+      NewTabPrefsProvider.prefs.off(PREF_SELECTED_LOCALE, this._updateRemoteMaybe);
+      NewTabPrefsProvider.prefs.off(PREF_MATCH_OS_LOCALE, this._updateRemoteMaybe);
+      NewTabPrefsProvider.prefs.off(PREF_REMOTE_MODE, this._updateRemoteMaybe);
+      NewTabPrefsProvider.prefs.off(PREF_REMOTE_VERSION, this._updateRemoteMaybe);
+      this._remoteEnabled = false;
+    }
+    if (!csTest) {
+      this._newTabURL = ABOUT_URL;
+    }
+    return true;
+  },
+
+  /*
+   * Generate a default url based on remote mode, version, locale and update channel
+   */
+  generateRemoteURL() {
+    let releaseName = this.releaseFromUpdateChannel(UpdateUtils.UpdateChannel);
+    let path = REMOTE_NEWTAB_PATH
+      .replace("%VERSION%", this.remoteVersion)
+      .replace("%LOCALE%", Locale.getLocale())
+      .replace("%CHANNEL%", releaseName);
+    let mode = Services.prefs.getCharPref(PREF_REMOTE_MODE, "production");
+    if (!(mode in NewTabRemoteResources.MODE_CHANNEL_MAP)) {
+      mode = "production";
+    }
+    return NewTabRemoteResources.MODE_CHANNEL_MAP[mode].origin + path;
+  },
+
+  /*
+   * Returns the default URL.
+   *
+   * This URL only depends on the browser.newtabpage.remote pref. Overriding
+   * the newtab page has no effect on the result of this function.
+   *
+   * The result is also the remote URL if this is in a test (PREF_REMOTE_CS_TEST)
+   *
+   * @returns {String} the default newtab URL, remote or local depending on browser.newtabpage.remote
+   */
+  get defaultURL() {
+    let csTest = Services.prefs.getBoolPref(PREF_REMOTE_CS_TEST);
+    if (this._remoteEnabled || csTest)  {
+      return this._remoteURL;
+    }
+    return LOCAL_NEWTAB_URL;
+  },
+
+  /*
+   * Updates the remote location when the page is not overriden.
+   *
+   * Useful when there is a dependent pref change
+   */
+  _updateRemoteMaybe() {
+    if (!this._remoteEnabled || this._overridden) {
+      return;
+    }
+
+    let url = this.generateRemoteURL();
+    if (url !== this._remoteURL) {
+      this._remoteURL = url;
+      Services.obs.notifyObservers(null, "newtab-url-changed",
+        this._remoteURL);
+    }
+  },
+
+  /**
+   * Returns the release name from an Update Channel name
+   *
+   * @returns {String} a release name based on the update channel. Defaults to nightly
+   */
+  releaseFromUpdateChannel(channelName) {
+    return VALID_CHANNELS.has(channelName) ? channelName : "nightly";
+  },
+
+  get newTabURL() {
+    return this._newTabURL;
+  },
+
+  get remoteVersion() {
+    return Services.prefs.getCharPref(PREF_REMOTE_VERSION, "1");
+  },
+
+  get remoteReleaseName() {
+    return this.releaseFromUpdateChannel(UpdateUtils.UpdateChannel);
+  },
+
+  set newTabURL(aNewTabURL) {
+    let csTest = Services.prefs.getBoolPref(PREF_REMOTE_CS_TEST);
+    aNewTabURL = aNewTabURL.trim();
+    if (aNewTabURL === ABOUT_URL) {
+      // avoid infinite redirects in case one sets the URL to about:newtab
+      this.resetNewTabURL();
+      return;
+    } else if (aNewTabURL === "") {
+      aNewTabURL = "about:blank";
+    }
+    let remoteURL = this.generateRemoteURL();
+    let prefRemoteEnabled = Services.prefs.getBoolPref(PREF_REMOTE_ENABLED);
+    let isResetLocal = !prefRemoteEnabled && aNewTabURL === LOCAL_NEWTAB_URL;
+    let isResetRemote = prefRemoteEnabled && aNewTabURL === remoteURL;
+
+    if (isResetLocal || isResetRemote) {
+      if (this._overriden && !csTest) {
+        // only trigger a reset if previously overridden and this is no test
+        this.resetNewTabURL();
+      }
+      return;
+    }
+    // turn off remote state if needed
+    if (!csTest) {
+      this.toggleRemote(false);
+    } else {
+      // if this is a test, we want the remoteURL to be set
+      this._remoteURL = aNewTabURL;
+    }
+    this._newTabURL = aNewTabURL;
+    this._overridden = true;
+    Services.obs.notifyObservers(null, "newtab-url-changed", this._newTabURL);
+  },
+
+  get overridden() {
+    return this._overridden;
+  },
+
+  get remoteEnabled() {
+    return this._remoteEnabled;
+  },
+
+  resetNewTabURL() {
+    this._overridden = false;
+    this._newTabURL = ABOUT_URL;
+    this.toggleRemote(Services.prefs.getBoolPref(PREF_REMOTE_ENABLED), true);
+    Services.obs.notifyObservers(null, "newtab-url-changed", this._newTabURL);
+  }
+};
+
+this.NSGetFactory = XPCOMUtils.generateNSGetFactory([AboutNewTabService]);