diff options
Diffstat (limited to 'toolkit/components/search/orginal/SearchSuggestionController.jsm')
-rw-r--r-- | toolkit/components/search/orginal/SearchSuggestionController.jsm | 396 |
1 files changed, 396 insertions, 0 deletions
diff --git a/toolkit/components/search/orginal/SearchSuggestionController.jsm b/toolkit/components/search/orginal/SearchSuggestionController.jsm new file mode 100644 index 000000000..0858974bf --- /dev/null +++ b/toolkit/components/search/orginal/SearchSuggestionController.jsm @@ -0,0 +1,396 @@ +/* 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 = ["SearchSuggestionController"]; + +const { classes: Cc, interfaces: Ci, utils: Cu } = Components; + +Cu.import("resource://gre/modules/XPCOMUtils.jsm"); +Cu.import("resource://gre/modules/Services.jsm"); +Cu.import("resource://gre/modules/Promise.jsm"); +XPCOMUtils.defineLazyModuleGetter(this, "NS_ASSERT", "resource://gre/modules/debug.js"); + +const SEARCH_RESPONSE_SUGGESTION_JSON = "application/x-suggestions+json"; +const DEFAULT_FORM_HISTORY_PARAM = "searchbar-history"; +const HTTP_OK = 200; +const REMOTE_TIMEOUT = 500; // maximum time (ms) to wait before giving up on a remote suggestions +const BROWSER_SUGGEST_PREF = "browser.search.suggest.enabled"; + +/** + * Remote search suggestions will be shown if gRemoteSuggestionsEnabled + * is true. Global because only one pref observer is needed for all instances. + */ +var gRemoteSuggestionsEnabled = Services.prefs.getBoolPref(BROWSER_SUGGEST_PREF); +Services.prefs.addObserver(BROWSER_SUGGEST_PREF, function(aSubject, aTopic, aData) { + gRemoteSuggestionsEnabled = Services.prefs.getBoolPref(BROWSER_SUGGEST_PREF); +}, false); + +/** + * SearchSuggestionController.jsm exists as a helper module to allow multiple consumers to request and display + * search suggestions from a given engine, regardless of the base implementation. Much of this + * code was originally in nsSearchSuggestions.js until it was refactored to separate it from the + * nsIAutoCompleteSearch dependency. + * One instance of SearchSuggestionController should be used per field since form history results are cached. + */ + +/** + * @param {function} [callback] - Callback for search suggestion results. You can use the promise + * returned by the search method instead if you prefer. + * @constructor + */ +this.SearchSuggestionController = function SearchSuggestionController(callback = null) { + this._callback = callback; +}; + +this.SearchSuggestionController.prototype = { + /** + * The maximum number of local form history results to return. This limit is + * only enforced if remote results are also returned. + */ + maxLocalResults: 5, + + /** + * The maximum number of remote search engine results to return. + * We'll actually only display at most + * maxRemoteResults - <displayed local results count> remote results. + */ + maxRemoteResults: 10, + + /** + * The maximum time (ms) to wait before giving up on a remote suggestions. + */ + remoteTimeout: REMOTE_TIMEOUT, + + /** + * The additional parameter used when searching form history. + */ + formHistoryParam: DEFAULT_FORM_HISTORY_PARAM, + + // Private properties + /** + * The last form history result used to improve the performance of subsequent searches. + * This shouldn't be used for any other purpose as it is never cleared and therefore could be stale. + */ + _formHistoryResult: null, + + /** + * The remote server timeout timer, if applicable. The timer starts when form history + * search is completed. + */ + _remoteResultTimer: null, + + /** + * The deferred for the remote results before its promise is resolved. + */ + _deferredRemoteResult: null, + + /** + * The optional result callback registered from the constructor. + */ + _callback: null, + + /** + * The XMLHttpRequest object for remote results. + */ + _request: null, + + // Public methods + + /** + * Fetch search suggestions from all of the providers. Fetches in progress will be stopped and + * results from them will not be provided. + * + * @param {string} searchTerm - the term to provide suggestions for + * @param {bool} privateMode - whether the request is being made in the context of private browsing + * @param {nsISearchEngine} engine - search engine for the suggestions. + * + * @return {Promise} resolving to an object containing results or null. + */ + fetch: function(searchTerm, privateMode, engine) { + // There is no smart filtering from previous results here (as there is when looking through + // history/form data) because the result set returned by the server is different for every typed + // value - e.g. "ocean breathes" does not return a subset of the results returned for "ocean". + + this.stop(); + + if (!Services.search.isInitialized) { + throw new Error("Search not initialized yet (how did you get here?)"); + } + if (typeof privateMode === "undefined") { + throw new Error("The privateMode argument is required to avoid unintentional privacy leaks"); + } + if (!(engine instanceof Ci.nsISearchEngine)) { + throw new Error("Invalid search engine"); + } + if (!this.maxLocalResults && !this.maxRemoteResults) { + throw new Error("Zero results expected, what are you trying to do?"); + } + if (this.maxLocalResults < 0 || this.maxRemoteResults < 0) { + throw new Error("Number of requested results must be positive"); + } + + // Array of promises to resolve before returning results. + let promises = []; + this._searchString = searchTerm; + + // Remote results + if (searchTerm && gRemoteSuggestionsEnabled && this.maxRemoteResults && + engine.supportsResponseType(SEARCH_RESPONSE_SUGGESTION_JSON)) { + this._deferredRemoteResult = this._fetchRemote(searchTerm, engine, privateMode); + promises.push(this._deferredRemoteResult.promise); + } + + // Local results from form history + if (this.maxLocalResults) { + let deferredHistoryResult = this._fetchFormHistory(searchTerm); + promises.push(deferredHistoryResult.promise); + } + + function handleRejection(reason) { + if (reason == "HTTP request aborted") { + // Do nothing since this is normal. + return null; + } + Cu.reportError("SearchSuggestionController rejection: " + reason); + return null; + } + return Promise.all(promises).then(this._dedupeAndReturnResults.bind(this), handleRejection); + }, + + /** + * Stop pending fetches so no results are returned from them. + * + * Note: If there was no remote results fetched, the fetching cannot be stopped and local results + * will still be returned because stopping relies on aborting the XMLHTTPRequest to reject the + * promise for Promise.all. + */ + stop: function() { + if (this._request) { + this._request.abort(); + } else if (!this.maxRemoteResults) { + Cu.reportError("SearchSuggestionController: Cannot stop fetching if remote results were not "+ + "requested"); + } + this._reset(); + }, + + // Private methods + + _fetchFormHistory: function(searchTerm) { + let deferredFormHistory = Promise.defer(); + + let acSearchObserver = { + // Implements nsIAutoCompleteSearch + onSearchResult: (search, result) => { + this._formHistoryResult = result; + + if (this._request) { + this._remoteResultTimer = Cc["@mozilla.org/timer;1"]. + createInstance(Ci.nsITimer); + this._remoteResultTimer.initWithCallback(this._onRemoteTimeout.bind(this), + this.remoteTimeout || REMOTE_TIMEOUT, + Ci.nsITimer.TYPE_ONE_SHOT); + } + + switch (result.searchResult) { + case Ci.nsIAutoCompleteResult.RESULT_SUCCESS: + case Ci.nsIAutoCompleteResult.RESULT_NOMATCH: + if (result.searchString !== this._searchString) { + deferredFormHistory.resolve("Unexpected response, this._searchString does not match form history response"); + return; + } + let fhEntries = []; + for (let i = 0; i < result.matchCount; ++i) { + fhEntries.push(result.getValueAt(i)); + } + deferredFormHistory.resolve({ + result: fhEntries, + formHistoryResult: result, + }); + break; + case Ci.nsIAutoCompleteResult.RESULT_FAILURE: + case Ci.nsIAutoCompleteResult.RESULT_IGNORED: + deferredFormHistory.resolve("Form History returned RESULT_FAILURE or RESULT_IGNORED"); + break; + } + }, + }; + + let formHistory = Cc["@mozilla.org/autocomplete/search;1?name=form-history"]. + createInstance(Ci.nsIAutoCompleteSearch); + formHistory.startSearch(searchTerm, this.formHistoryParam || DEFAULT_FORM_HISTORY_PARAM, + this._formHistoryResult, + acSearchObserver); + return deferredFormHistory; + }, + + /** + * Fetch suggestions from the search engine over the network. + */ + _fetchRemote: function(searchTerm, engine, privateMode) { + let deferredResponse = Promise.defer(); + this._request = Cc["@mozilla.org/xmlextras/xmlhttprequest;1"]. + createInstance(Ci.nsIXMLHttpRequest); + let submission = engine.getSubmission(searchTerm, + SEARCH_RESPONSE_SUGGESTION_JSON); + let method = (submission.postData ? "POST" : "GET"); + this._request.open(method, submission.uri.spec, true); + if (this._request.channel instanceof Ci.nsIPrivateBrowsingChannel) { + this._request.channel.setPrivate(privateMode); + } + this._request.mozBackgroundRequest = true; // suppress dialogs and fail silently + + this._request.addEventListener("load", this._onRemoteLoaded.bind(this, deferredResponse)); + this._request.addEventListener("error", (evt) => deferredResponse.resolve("HTTP error")); + // Reject for an abort assuming it's always from .stop() in which case we shouldn't return local + // or remote results for existing searches. + this._request.addEventListener("abort", (evt) => deferredResponse.reject("HTTP request aborted")); + + this._request.send(submission.postData); + + return deferredResponse; + }, + + /** + * Called when the request completed successfully (thought the HTTP status could be anything) + * so we can handle the response data. + * @private + */ + _onRemoteLoaded: function(deferredResponse) { + if (!this._request) { + deferredResponse.resolve("Got HTTP response after the request was cancelled"); + return; + } + + let status, serverResults; + try { + status = this._request.status; + } catch (e) { + // The XMLHttpRequest can throw NS_ERROR_NOT_AVAILABLE. + deferredResponse.resolve("Unknown HTTP status: " + e); + return; + } + + if (status != HTTP_OK || this._request.responseText == "") { + deferredResponse.resolve("Non-200 status or empty HTTP response: " + status); + return; + } + + try { + serverResults = JSON.parse(this._request.responseText); + } catch(ex) { + deferredResponse.resolve("Failed to parse suggestion JSON: " + ex); + return; + } + + if (!serverResults[0] || + this._searchString.localeCompare(serverResults[0], undefined, + { sensitivity: "base" })) { + // something is wrong here so drop remote results + deferredResponse.resolve("Unexpected response, this._searchString does not match remote response"); + return; + } + let results = serverResults[1] || []; + deferredResponse.resolve({ result: results }); + }, + + /** + * Called when this._remoteResultTimer fires indicating the remote request took too long. + */ + _onRemoteTimeout: function () { + this._request = null; + + // FIXME: bug 387341 + // Need to break the cycle between us and the timer. + this._remoteResultTimer = null; + + // The XMLHTTPRequest for suggest results is taking too long + // so send out the form history results and cancel the request. + if (this._deferredRemoteResult) { + this._deferredRemoteResult.resolve("HTTP Timeout"); + this._deferredRemoteResult = null; + } + }, + + /** + * @param {Array} suggestResults - an array of result objects from different sources (local or remote) + * @return {Object} + */ + _dedupeAndReturnResults: function(suggestResults) { + if (this._searchString === null) { + // _searchString can be null if stop() was called and remote suggestions + // were disabled (stopping if we are fetching remote suggestions will + // cause a promise rejection before we reach _dedupeAndReturnResults). + return null; + } + + let results = { + term: this._searchString, + remote: [], + local: [], + formHistoryResult: null, + }; + + for (let result of suggestResults) { + if (typeof result === "string") { // Failure message + Cu.reportError("SearchSuggestionController: " + result); + } else if (result.formHistoryResult) { // Local results have a formHistoryResult property. + results.formHistoryResult = result.formHistoryResult; + results.local = result.result || []; + } else { // Remote result + results.remote = result.result || []; + } + } + + // If we have remote results, cap the number of local results + if (results.remote.length) { + results.local = results.local.slice(0, this.maxLocalResults); + } + + // We don't want things to appear in both history and suggestions so remove entries from + // remote results that are already in local. + if (results.remote.length && results.local.length) { + for (let i = 0; i < results.local.length; ++i) { + let term = results.local[i]; + let dupIndex = results.remote.indexOf(term); + if (dupIndex != -1) { + results.remote.splice(dupIndex, 1); + } + } + } + + // Trim the number of results to the maximum requested (now that we've pruned dupes). + results.remote = + results.remote.slice(0, this.maxRemoteResults - results.local.length); + + if (this._callback) { + this._callback(results); + } + this._reset(); + + return results; + }, + + _reset: function() { + this._request = null; + if (this._remoteResultTimer) { + this._remoteResultTimer.cancel(); + this._remoteResultTimer = null; + } + this._deferredRemoteResult = null; + this._searchString = null; + }, +}; + +/** + * Determines whether the given engine offers search suggestions. + * + * @param {nsISearchEngine} engine - The search engine + * @return {boolean} True if the engine offers suggestions and false otherwise. + */ +this.SearchSuggestionController.engineOffersSuggestions = function(engine) { + return engine.supportsResponseType(SEARCH_RESPONSE_SUGGESTION_JSON); +}; |