1 files changed, 285 insertions, 0 deletions
diff --git a/netwerk/protocol/http/UserAgentUpdates.jsm b/netwerk/protocol/http/UserAgentUpdates.jsm
new file mode 100644
index 000000000..602705ebe
--- /dev/null
+++ b/netwerk/protocol/http/UserAgentUpdates.jsm
@@ -0,0 +1,285 @@
+/* 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";
+
+this.EXPORTED_SYMBOLS = ["UserAgentUpdates"];
+
+const Ci = Components.interfaces;
+const Cc = Components.classes;
+const Cu = Components.utils;
+
+Cu.import("resource://gre/modules/AppConstants.jsm");
+Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+
+XPCOMUtils.defineLazyModuleGetter(
+  this, "FileUtils", "resource://gre/modules/FileUtils.jsm");
+
+XPCOMUtils.defineLazyModuleGetter(
+  this, "NetUtil", "resource://gre/modules/NetUtil.jsm");
+
+XPCOMUtils.defineLazyModuleGetter(
+  this, "OS", "resource://gre/modules/osfile.jsm");
+
+XPCOMUtils.defineLazyModuleGetter(
+  this, "Promise", "resource://gre/modules/Promise.jsm");
+
+XPCOMUtils.defineLazyModuleGetter(
+  this, "UpdateUtils", "resource://gre/modules/UpdateUtils.jsm");
+
+XPCOMUtils.defineLazyServiceGetter(
+  this, "gUpdateTimer", "@mozilla.org/updates/timer-manager;1", "nsIUpdateTimerManager");
+
+XPCOMUtils.defineLazyGetter(this, "gApp",
+  function() {
+    return Cc["@mozilla.org/xre/app-info;1"].getService(Ci.nsIXULAppInfo)
+                                            .QueryInterface(Ci.nsIXULRuntime);
+  });
+
+XPCOMUtils.defineLazyGetter(this, "gDecoder",
+  function() { return new TextDecoder(); }
+);
+
+XPCOMUtils.defineLazyGetter(this, "gEncoder",
+  function() { return new TextEncoder(); }
+);
+
+const TIMER_ID = "user-agent-updates-timer";
+
+const PREF_UPDATES = "general.useragent.updates.";
+const PREF_UPDATES_ENABLED = PREF_UPDATES + "enabled";
+const PREF_UPDATES_URL = PREF_UPDATES + "url";
+const PREF_UPDATES_INTERVAL = PREF_UPDATES + "interval";
+const PREF_UPDATES_RETRY = PREF_UPDATES + "retry";
+const PREF_UPDATES_TIMEOUT = PREF_UPDATES + "timeout";
+const PREF_UPDATES_LASTUPDATED = PREF_UPDATES + "lastupdated";
+
+const KEY_PREFDIR = "PrefD";
+const KEY_APPDIR = "XCurProcD";
+const FILE_UPDATES = "ua-update.json";
+
+const PREF_APP_DISTRIBUTION = "distribution.id";
+const PREF_APP_DISTRIBUTION_VERSION = "distribution.version";
+
+var gInitialized = false;
+
+function readChannel(url) {
+  return new Promise((resolve, reject) => {
+    try {
+      let channel = NetUtil.newChannel({uri: url, loadUsingSystemPrincipal: true});
+      channel.contentType = "application/json";
+
+      NetUtil.asyncFetch(channel, (inputStream, status) => {
+        if (!Components.isSuccessCode(status)) {
+          reject();
+          return;
+        }
+
+        let data = JSON.parse(
+          NetUtil.readInputStreamToString(inputStream, inputStream.available())
+        );
+        resolve(data);
+      });
+    } catch (ex) {
+      reject(new Error("UserAgentUpdates: Could not fetch " + url + " " +
+                       ex + "\n" + ex.stack));
+    }
+  });
+}
+
+this.UserAgentUpdates = {
+  init: function(callback) {
+    if (gInitialized) {
+      return;
+    }
+    gInitialized = true;
+
+    this._callback = callback;
+    this._lastUpdated = 0;
+    this._applySavedUpdate();
+
+    Services.prefs.addObserver(PREF_UPDATES, this, false);
+  },
+
+  uninit: function() {
+    if (!gInitialized) {
+      return;
+    }
+    gInitialized = false;
+    Services.prefs.removeObserver(PREF_UPDATES, this);
+  },
+
+  _applyUpdate: function(update) {
+    // Check pref again in case it has changed
+    if (update && this._getPref(PREF_UPDATES_ENABLED, false)) {
+      this._callback(update);
+    } else {
+      this._callback(null);
+    }
+  },
+
+  _applySavedUpdate: function() {
+    if (!this._getPref(PREF_UPDATES_ENABLED, false)) {
+      // remove previous overrides
+      this._applyUpdate(null);
+      return;
+    }
+    // try loading from profile dir, then from app dir
+    let dirs = [KEY_PREFDIR, KEY_APPDIR];
+
+    dirs.reduce((prevLoad, dir) => {
+      let file = FileUtils.getFile(dir, [FILE_UPDATES], true).path;
+      // tryNext returns promise to read file under dir and parse it
+      let tryNext = () => OS.File.read(file).then(
+        (bytes) => {
+          let update = JSON.parse(gDecoder.decode(bytes));
+          if (!update) {
+            throw new Error("invalid update");
+          }
+          return update;
+        }
+      );
+      // try to load next one if the previous load failed
+      return prevLoad ? prevLoad.then(null, tryNext) : tryNext();
+    }, null).then(null, (ex) => {
+      if (AppConstants.platform !== "android") {
+        // All previous (non-Android) load attempts have failed, so we bail.
+        throw new Error("UserAgentUpdates: Failed to load " + FILE_UPDATES +
+                         ex + "\n" + ex.stack);
+      }
+      // Make one last attempt to read from the Fennec APK root.
+      return readChannel("resource://android/" + FILE_UPDATES);
+    }).then((update) => {
+      // Apply update if loading was successful
+      this._applyUpdate(update);
+    }).catch(Cu.reportError);
+    this._scheduleUpdate();
+  },
+
+  _saveToFile: function(update) {
+    let file = FileUtils.getFile(KEY_PREFDIR, [FILE_UPDATES], true);
+    let path = file.path;
+    let bytes = gEncoder.encode(JSON.stringify(update));
+    OS.File.writeAtomic(path, bytes, {tmpPath: path + ".tmp"}).then(
+      () => {
+        this._lastUpdated = Date.now();
+        Services.prefs.setCharPref(
+          PREF_UPDATES_LASTUPDATED, this._lastUpdated.toString());
+      },
+      Cu.reportError
+    );
+  },
+
+  _getPref: function(name, def) {
+    try {
+      switch (typeof def) {
+        case "number": return Services.prefs.getIntPref(name);
+        case "boolean": return Services.prefs.getBoolPref(name);
+      }
+      return Services.prefs.getCharPref(name);
+    } catch (e) {
+      return def;
+    }
+  },
+
+  _getParameters() {
+    return {
+      "%DATE%": function() { return Date.now().toString(); },
+      "%PRODUCT%": function() { return gApp.name; },
+      "%APP_ID%": function() { return gApp.ID; },
+      "%APP_VERSION%": function() { return gApp.version; },
+      "%BUILD_ID%": function() { return gApp.appBuildID; },
+      "%OS%": function() { return gApp.OS; },
+      "%CHANNEL%": function() { return UpdateUtils.UpdateChannel; },
+      "%DISTRIBUTION%": function() { return this._getPref(PREF_APP_DISTRIBUTION, ""); },
+      "%DISTRIBUTION_VERSION%": function() { return this._getPref(PREF_APP_DISTRIBUTION_VERSION, ""); },
+    };
+  },
+
+  _getUpdateURL: function() {
+    let url = this._getPref(PREF_UPDATES_URL, "");
+    let params = this._getParameters();
+    return url.replace(/%[A-Z_]+%/g, function(match) {
+      let param = params[match];
+      // preserve the %FOO% string (e.g. as an encoding) if it's not a valid parameter
+      return param ? encodeURIComponent(param()) : match;
+    });
+  },
+
+  _fetchUpdate: function(url, success, error) {
+    let request = Cc["@mozilla.org/xmlextras/xmlhttprequest;1"]
+                    .createInstance(Ci.nsIXMLHttpRequest);
+    request.mozBackgroundRequest = true;
+    request.timeout = this._getPref(PREF_UPDATES_TIMEOUT, 60000);
+    request.open("GET", url, true);
+    request.overrideMimeType("application/json");
+    request.responseType = "json";
+
+    request.addEventListener("load", function() {
+      let response = request.response;
+      response ? success(response) : error();
+    });
+    request.addEventListener("error", error);
+    request.send();
+  },
+
+  _update: function() {
+    let url = this._getUpdateURL();
+    url && this._fetchUpdate(url,
+      (function(response) { // success
+        // apply update and save overrides to profile
+        this._applyUpdate(response);
+        this._saveToFile(response);
+        this._scheduleUpdate(); // cancel any retries
+      }).bind(this),
+      (function(response) { // error
+        this._scheduleUpdate(true /* retry */);
+      }).bind(this));
+  },
+
+  _scheduleUpdate: function(retry) {
+    // only schedule updates in the main process
+    if (gApp.processType !== Ci.nsIXULRuntime.PROCESS_TYPE_DEFAULT) {
+      return;
+    }
+    let interval = this._getPref(PREF_UPDATES_INTERVAL, 604800 /* 1 week */);
+    if (retry) {
+      interval = this._getPref(PREF_UPDATES_RETRY, interval);
+    }
+    gUpdateTimer.registerTimer(TIMER_ID, this, Math.max(1, interval));
+  },
+
+  notify: function(timer) {
+    // timer notification
+    if (this._getPref(PREF_UPDATES_ENABLED, false)) {
+      this._update();
+    }
+  },
+
+  observe: function(subject, topic, data) {
+    switch (topic) {
+      case "nsPref:changed":
+        if (data === PREF_UPDATES_ENABLED) {
+          this._applySavedUpdate();
+        } else if (data === PREF_UPDATES_INTERVAL) {
+          this._scheduleUpdate();
+        } else if (data === PREF_UPDATES_LASTUPDATED) {
+          // reload from file if there has been an update
+          let lastUpdated = parseInt(
+            this._getPref(PREF_UPDATES_LASTUPDATED, "0"), 0);
+          if (lastUpdated > this._lastUpdated) {
+            this._applySavedUpdate();
+            this._lastUpdated = lastUpdated;
+          }
+        }
+        break;
+    }
+  },
+
+  QueryInterface: XPCOMUtils.generateQI([
+    Ci.nsIObserver,
+    Ci.nsITimerCallback,
+  ]),
+};