1 files changed, 566 insertions, 0 deletions
diff --git a/modules/ContentSearch.jsm b/modules/ContentSearch.jsm
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--- /dev/null
+++ b/modules/ContentSearch.jsm
@@ -0,0 +1,566 @@
+/* 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, Services, Task, Promise, SearchSuggestionController, FormHistory, PrivateBrowsingUtils */
+"use strict";
+
+this.EXPORTED_SYMBOLS = [
+  "ContentSearch",
+];
+
+const { classes: Cc, interfaces: Ci, utils: Cu } = Components;
+
+Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/Promise.jsm");
+Cu.import("resource://gre/modules/Task.jsm");
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+
+XPCOMUtils.defineLazyModuleGetter(this, "FormHistory",
+  "resource://gre/modules/FormHistory.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "PrivateBrowsingUtils",
+  "resource://gre/modules/PrivateBrowsingUtils.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "SearchSuggestionController",
+  "resource://gre/modules/SearchSuggestionController.jsm");
+
+const INBOUND_MESSAGE = "ContentSearch";
+const OUTBOUND_MESSAGE = INBOUND_MESSAGE;
+const MAX_LOCAL_SUGGESTIONS = 3;
+const MAX_SUGGESTIONS = 6;
+
+/**
+ * ContentSearch receives messages named INBOUND_MESSAGE and sends messages
+ * named OUTBOUND_MESSAGE.  The data of each message is expected to look like
+ * { type, data }.  type is the message's type (or subtype if you consider the
+ * type of the message itself to be INBOUND_MESSAGE), and data is data that is
+ * specific to the type.
+ *
+ * Inbound messages have the following types:
+ *
+ *   AddFormHistoryEntry
+ *     Adds an entry to the search form history.
+ *     data: the entry, a string
+ *   GetSuggestions
+ *     Retrieves an array of search suggestions given a search string.
+ *     data: { engineName, searchString, [remoteTimeout] }
+ *   GetState
+ *     Retrieves the current search engine state.
+ *     data: null
+ *   GetStrings
+ *     Retrieves localized search UI strings.
+ *     data: null
+ *   ManageEngines
+ *     Opens the search engine management window.
+ *     data: null
+ *   RemoveFormHistoryEntry
+ *     Removes an entry from the search form history.
+ *     data: the entry, a string
+ *   Search
+ *     Performs a search.
+ *     Any GetSuggestions messages in the queue from the same target will be
+ *     cancelled.
+ *     data: { engineName, searchString, healthReportKey, searchPurpose }
+ *   SetCurrentEngine
+ *     Sets the current engine.
+ *     data: the name of the engine
+ *   SpeculativeConnect
+ *     Speculatively connects to an engine.
+ *     data: the name of the engine
+ *
+ * Outbound messages have the following types:
+ *
+ *   CurrentEngine
+ *     Broadcast when the current engine changes.
+ *     data: see _currentEngineObj
+ *   CurrentState
+ *     Broadcast when the current search state changes.
+ *     data: see currentStateObj
+ *   State
+ *     Sent in reply to GetState.
+ *     data: see currentStateObj
+ *   Strings
+ *     Sent in reply to GetStrings
+ *     data: Object containing string names and values for the current locale.
+ *   Suggestions
+ *     Sent in reply to GetSuggestions.
+ *     data: see _onMessageGetSuggestions
+ *   SuggestionsCancelled
+ *     Sent in reply to GetSuggestions when pending GetSuggestions events are
+ *     cancelled.
+ *     data: null
+ */
+
+this.ContentSearch = {
+
+  // Inbound events are queued and processed in FIFO order instead of handling
+  // them immediately, which would result in non-FIFO responses due to the
+  // asynchrononicity added by converting image data URIs to ArrayBuffers.
+  _eventQueue: [],
+  _currentEventPromise: null,
+
+  // This is used to handle search suggestions.  It maps xul:browsers to objects
+  // { controller, previousFormHistoryResult }.  See _onMessageGetSuggestions.
+  _suggestionMap: new WeakMap(),
+
+  // Resolved when we finish shutting down.
+  _destroyedPromise: null,
+
+  // The current controller and browser in _onMessageGetSuggestions.  Allows
+  // fetch cancellation from _cancelSuggestions.
+  _currentSuggestion: null,
+
+  init: function () {
+    Cc["@mozilla.org/globalmessagemanager;1"].
+      getService(Ci.nsIMessageListenerManager).
+      addMessageListener(INBOUND_MESSAGE, this);
+    Services.obs.addObserver(this, "browser-search-engine-modified", false);
+    Services.obs.addObserver(this, "shutdown-leaks-before-check", false);
+    Services.prefs.addObserver("browser.search.hiddenOneOffs", this, false);
+    this._stringBundle = Services.strings.createBundle("chrome://global/locale/autocomplete.properties");
+  },
+
+  get searchSuggestionUIStrings() {
+    if (this._searchSuggestionUIStrings) {
+      return this._searchSuggestionUIStrings;
+    }
+    this._searchSuggestionUIStrings = {};
+    let searchBundle = Services.strings.createBundle("chrome://browser/locale/search.properties");
+    let stringNames = ["searchHeader", "searchPlaceholder", "searchForSomethingWith",
+                       "searchWithHeader", "searchSettings"];
+
+    for (let name of stringNames) {
+      this._searchSuggestionUIStrings[name] = searchBundle.GetStringFromName(name);
+    }
+    return this._searchSuggestionUIStrings;
+  },
+
+  destroy: function () {
+    if (this._destroyedPromise) {
+      return this._destroyedPromise;
+    }
+
+    Cc["@mozilla.org/globalmessagemanager;1"].
+      getService(Ci.nsIMessageListenerManager).
+      removeMessageListener(INBOUND_MESSAGE, this);
+    Services.obs.removeObserver(this, "browser-search-engine-modified");
+    Services.obs.removeObserver(this, "shutdown-leaks-before-check");
+
+    this._eventQueue.length = 0;
+    this._destroyedPromise = Promise.resolve(this._currentEventPromise);
+    return this._destroyedPromise;
+  },
+
+  /**
+   * Focuses the search input in the page with the given message manager.
+   * @param  messageManager
+   *         The MessageManager object of the selected browser.
+   */
+  focusInput: function (messageManager) {
+    messageManager.sendAsyncMessage(OUTBOUND_MESSAGE, {
+      type: "FocusInput"
+    });
+  },
+
+  receiveMessage: function (msg) {
+    // Add a temporary event handler that exists only while the message is in
+    // the event queue.  If the message's source docshell changes browsers in
+    // the meantime, then we need to update msg.target.  event.detail will be
+    // the docshell's new parent <xul:browser> element.
+    msg.handleEvent = event => {
+      let browserData = this._suggestionMap.get(msg.target);
+      if (browserData) {
+        this._suggestionMap.delete(msg.target);
+        this._suggestionMap.set(event.detail, browserData);
+      }
+      msg.target.removeEventListener("SwapDocShells", msg, true);
+      msg.target = event.detail;
+      msg.target.addEventListener("SwapDocShells", msg, true);
+    };
+    msg.target.addEventListener("SwapDocShells", msg, true);
+
+    // Search requests cause cancellation of all Suggestion requests from the
+    // same browser.
+    if (msg.data.type === "Search") {
+      this._cancelSuggestions(msg);
+    }
+
+    this._eventQueue.push({
+      type: "Message",
+      data: msg,
+    });
+    this._processEventQueue();
+  },
+
+  observe: function (subj, topic, data) {
+    switch (topic) {
+    case "nsPref:changed":
+    case "browser-search-engine-modified":
+      this._eventQueue.push({
+        type: "Observe",
+        data: data,
+      });
+      this._processEventQueue();
+      break;
+    case "shutdown-leaks-before-check":
+      subj.wrappedJSObject.client.addBlocker(
+        "ContentSearch: Wait until the service is destroyed", () => this.destroy());
+      break;
+    }
+  },
+
+  removeFormHistoryEntry: function (msg, entry) {
+    let browserData = this._suggestionDataForBrowser(msg.target);
+    if (browserData && browserData.previousFormHistoryResult) {
+      let { previousFormHistoryResult } = browserData;
+      for (let i = 0; i < previousFormHistoryResult.matchCount; i++) {
+        if (previousFormHistoryResult.getValueAt(i) === entry) {
+          previousFormHistoryResult.removeValueAt(i, true);
+          break;
+        }
+      }
+    }
+  },
+
+  performSearch: function (msg, data) {
+    this._ensureDataHasProperties(data, [
+      "engineName",
+      "searchString",
+      "healthReportKey",
+      "searchPurpose",
+    ]);
+    let engine = Services.search.getEngineByName(data.engineName);
+    let submission = engine.getSubmission(data.searchString, "", data.searchPurpose);
+    let browser = msg.target;
+    let win = browser.ownerGlobal;
+    if (!win) {
+      // The browser may have been closed between the time its content sent the
+      // message and the time we handle it.
+      return;
+    }
+    let where = win.whereToOpenLink(data.originalEvent);
+
+    // There is a chance that by the time we receive the search message, the user
+    // has switched away from the tab that triggered the search. If, based on the
+    // event, we need to load the search in the same tab that triggered it (i.e.
+    // where === "current"), openUILinkIn will not work because that tab is no
+    // longer the current one. For this case we manually load the URI.
+    if (where === "current") {
+      browser.loadURIWithFlags(submission.uri.spec,
+                               Ci.nsIWebNavigation.LOAD_FLAGS_NONE, null, null,
+                               submission.postData);
+    } else {
+      let params = {
+        postData: submission.postData,
+        inBackground: Services.prefs.getBoolPref("browser.tabs.loadInBackground"),
+      };
+      win.openUILinkIn(submission.uri.spec, where, params);
+    }
+    win.BrowserSearch.recordSearchInTelemetry(engine, data.healthReportKey,
+                                              { selection: data.selection });
+    return;
+  },
+
+  getSuggestions: Task.async(function* (engineName, searchString, browser, remoteTimeout=null) {
+    let engine = Services.search.getEngineByName(engineName);
+    if (!engine) {
+      throw new Error("Unknown engine name: " + engineName);
+    }
+
+    let browserData = this._suggestionDataForBrowser(browser, true);
+    let { controller } = browserData;
+    let ok = SearchSuggestionController.engineOffersSuggestions(engine);
+    controller.maxLocalResults = ok ? MAX_LOCAL_SUGGESTIONS : MAX_SUGGESTIONS;
+    controller.maxRemoteResults = ok ? MAX_SUGGESTIONS : 0;
+    controller.remoteTimeout = remoteTimeout || undefined;
+    let priv = PrivateBrowsingUtils.isBrowserPrivate(browser);
+    // fetch() rejects its promise if there's a pending request, but since we
+    // process our event queue serially, there's never a pending request.
+    this._currentSuggestion = { controller: controller, target: browser };
+    let suggestions = yield controller.fetch(searchString, priv, engine);
+    this._currentSuggestion = null;
+
+    // suggestions will be null if the request was cancelled
+    let result = {};
+    if (!suggestions) {
+      return result;
+    }
+
+    // Keep the form history result so RemoveFormHistoryEntry can remove entries
+    // from it.  Keeping only one result isn't foolproof because the client may
+    // try to remove an entry from one set of suggestions after it has requested
+    // more but before it's received them.  In that case, the entry may not
+    // appear in the new suggestions.  But that should happen rarely.
+    browserData.previousFormHistoryResult = suggestions.formHistoryResult;
+    result = {
+      engineName,
+      term: suggestions.term,
+      local: suggestions.local,
+      remote: suggestions.remote,
+    };
+    return result;
+  }),
+
+  addFormHistoryEntry: Task.async(function* (browser, entry="") {
+    let isPrivate = false;
+    try {
+      // isBrowserPrivate assumes that the passed-in browser has all the normal
+      // properties, which won't be true if the browser has been destroyed.
+      // That may be the case here due to the asynchronous nature of messaging.
+      isPrivate = PrivateBrowsingUtils.isBrowserPrivate(browser.target);
+    } catch (err) {
+      return false;
+    }
+    if (isPrivate || entry === "") {
+      return false;
+    }
+    let browserData = this._suggestionDataForBrowser(browser.target, true);
+    FormHistory.update({
+      op: "bump",
+      fieldname: browserData.controller.formHistoryParam,
+      value: entry,
+    }, {
+      handleCompletion: () => {},
+      handleError: err => {
+        Cu.reportError("Error adding form history entry: " + err);
+      },
+    });
+    return true;
+  }),
+
+  currentStateObj: Task.async(function* (uriFlag=false) {
+    let state = {
+      engines: [],
+      currentEngine: yield this._currentEngineObj(),
+    };
+    if (uriFlag) {
+      state.currentEngine.iconBuffer = Services.search.currentEngine.getIconURLBySize(16, 16);
+    }
+    let pref = Services.prefs.getCharPref("browser.search.hiddenOneOffs");
+    let hiddenList = pref ? pref.split(",") : [];
+    for (let engine of Services.search.getVisibleEngines()) {
+      let uri = engine.getIconURLBySize(16, 16);
+      let iconBuffer = uri;
+      if (!uriFlag) {
+        iconBuffer = yield this._arrayBufferFromDataURI(uri);
+      }
+      state.engines.push({
+        name: engine.name,
+        iconBuffer,
+        hidden: hiddenList.indexOf(engine.name) !== -1,
+      });
+    }
+    return state;
+  }),
+
+  _processEventQueue: function () {
+    if (this._currentEventPromise || !this._eventQueue.length) {
+      return;
+    }
+
+    let event = this._eventQueue.shift();
+
+    this._currentEventPromise = Task.spawn(function* () {
+      try {
+        yield this["_on" + event.type](event.data);
+      } catch (err) {
+        Cu.reportError(err);
+      } finally {
+        this._currentEventPromise = null;
+        this._processEventQueue();
+      }
+    }.bind(this));
+  },
+
+  _cancelSuggestions: function (msg) {
+    let cancelled = false;
+    // cancel active suggestion request
+    if (this._currentSuggestion && this._currentSuggestion.target === msg.target) {
+      this._currentSuggestion.controller.stop();
+      cancelled = true;
+    }
+    // cancel queued suggestion requests
+    for (let i = 0; i < this._eventQueue.length; i++) {
+      let m = this._eventQueue[i].data;
+      if (msg.target === m.target && m.data.type === "GetSuggestions") {
+        this._eventQueue.splice(i, 1);
+        cancelled = true;
+        i--;
+      }
+    }
+    if (cancelled) {
+      this._reply(msg, "SuggestionsCancelled");
+    }
+  },
+
+  _onMessage: Task.async(function* (msg) {
+    let methodName = "_onMessage" + msg.data.type;
+    if (methodName in this) {
+      yield this._initService();
+      yield this[methodName](msg, msg.data.data);
+      if (!Cu.isDeadWrapper(msg.target)) {
+        msg.target.removeEventListener("SwapDocShells", msg, true);
+      }
+    }
+  }),
+
+  _onMessageGetState: function (msg, data) {
+    return this.currentStateObj().then(state => {
+      this._reply(msg, "State", state);
+    });
+  },
+
+  _onMessageGetStrings: function (msg, data) {
+    this._reply(msg, "Strings", this.searchSuggestionUIStrings);
+  },
+
+  _onMessageSearch: function (msg, data) {
+    this.performSearch(msg, data);
+  },
+
+  _onMessageSetCurrentEngine: function (msg, data) {
+    Services.search.currentEngine = Services.search.getEngineByName(data);
+  },
+
+  _onMessageManageEngines: function (msg, data) {
+    let browserWin = msg.target.ownerGlobal;
+    browserWin.openPreferences("paneSearch");
+  },
+
+  _onMessageGetSuggestions: Task.async(function* (msg, data) {
+    this._ensureDataHasProperties(data, [
+      "engineName",
+      "searchString",
+    ]);
+    let {engineName, searchString} = data;
+    let suggestions = yield this.getSuggestions(engineName, searchString, msg.target);
+
+    this._reply(msg, "Suggestions", {
+      engineName: data.engineName,
+      searchString: suggestions.term,
+      formHistory: suggestions.local,
+      remote: suggestions.remote,
+    });
+  }),
+
+  _onMessageAddFormHistoryEntry: Task.async(function* (msg, entry) {
+    yield this.addFormHistoryEntry(msg, entry);
+  }),
+
+  _onMessageRemoveFormHistoryEntry: function (msg, entry) {
+    this.removeFormHistoryEntry(msg, entry);
+  },
+
+  _onMessageSpeculativeConnect: function (msg, engineName) {
+    let engine = Services.search.getEngineByName(engineName);
+    if (!engine) {
+      throw new Error("Unknown engine name: " + engineName);
+    }
+    if (msg.target.contentWindow) {
+      engine.speculativeConnect({
+        window: msg.target.contentWindow,
+      });
+    }
+  },
+
+  _onObserve: Task.async(function* (data) {
+    if (data === "engine-current") {
+      let engine = yield this._currentEngineObj();
+      this._broadcast("CurrentEngine", engine);
+    }
+    else if (data !== "engine-default") {
+      // engine-default is always sent with engine-current and isn't otherwise
+      // relevant to content searches.
+      let state = yield this.currentStateObj();
+      this._broadcast("CurrentState", state);
+    }
+  }),
+
+  _suggestionDataForBrowser: function (browser, create=false) {
+    let data = this._suggestionMap.get(browser);
+    if (!data && create) {
+      // Since one SearchSuggestionController instance is meant to be used per
+      // autocomplete widget, this means that we assume each xul:browser has at
+      // most one such widget.
+      data = {
+        controller: new SearchSuggestionController(),
+      };
+      this._suggestionMap.set(browser, data);
+    }
+    return data;
+  },
+
+  _reply: function (msg, type, data) {
+    // We reply asyncly to messages, and by the time we reply the browser we're
+    // responding to may have been destroyed.  messageManager is null then.
+    if (!Cu.isDeadWrapper(msg.target) && msg.target.messageManager) {
+      msg.target.messageManager.sendAsyncMessage(...this._msgArgs(type, data));
+    }
+  },
+
+  _broadcast: function (type, data) {
+    Cc["@mozilla.org/globalmessagemanager;1"].
+      getService(Ci.nsIMessageListenerManager).
+      broadcastAsyncMessage(...this._msgArgs(type, data));
+  },
+
+  _msgArgs: function (type, data) {
+    return [OUTBOUND_MESSAGE, {
+      type: type,
+      data: data,
+    }];
+  },
+
+  _currentEngineObj: Task.async(function* () {
+    let engine = Services.search.currentEngine;
+    let favicon = engine.getIconURLBySize(16, 16);
+    let placeholder = this._stringBundle.formatStringFromName(
+      "searchWithEngine", [engine.name], 1);
+    let obj = {
+      name: engine.name,
+      placeholder: placeholder,
+      iconBuffer: yield this._arrayBufferFromDataURI(favicon),
+    };
+    return obj;
+  }),
+
+  _arrayBufferFromDataURI: function (uri) {
+    if (!uri) {
+      return Promise.resolve(null);
+    }
+    let deferred = Promise.defer();
+    let xhr = Cc["@mozilla.org/xmlextras/xmlhttprequest;1"].
+              createInstance(Ci.nsIXMLHttpRequest);
+    xhr.open("GET", uri, true);
+    xhr.responseType = "arraybuffer";
+    xhr.onload = () => {
+      deferred.resolve(xhr.response);
+    };
+    xhr.onerror = xhr.onabort = xhr.ontimeout = () => {
+      deferred.resolve(null);
+    };
+    try {
+      // This throws if the URI is erroneously encoded.
+      xhr.send();
+    }
+    catch (err) {
+      return Promise.resolve(null);
+    }
+    return deferred.promise;
+  },
+
+  _ensureDataHasProperties: function (data, requiredProperties) {
+    for (let prop of requiredProperties) {
+      if (!(prop in data)) {
+        throw new Error("Message data missing required property: " + prop);
+      }
+    }
+  },
+
+  _initService: function () {
+    if (!this._initServicePromise) {
+      let deferred = Promise.defer();
+      this._initServicePromise = deferred.promise;
+      Services.search.init(() => deferred.resolve());
+    }
+    return this._initServicePromise;
+  },
+};