gecko-dev/dom/base/ConsoleAPIStorage.jsm

181 lines
5.8 KiB
JavaScript

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is ConsoleStorageService code.
*
* The Initial Developer of the Original Code is Mozilla Foundation
* Portions created by the Initial Developer are Copyright (C) 2010
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* David Dahl <ddahl@mozilla.com> (Original Author)
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
let Cu = Components.utils;
let Ci = Components.interfaces;
let Cc = Components.classes;
Cu.import("resource://gre/modules/XPCOMUtils.jsm");
Cu.import("resource://gre/modules/Services.jsm");
const STORAGE_MAX_EVENTS = 200;
XPCOMUtils.defineLazyGetter(this, "gPrivBrowsing", function () {
// private browsing may not be available in some Gecko Apps
try {
return Cc["@mozilla.org/privatebrowsing;1"].getService(Ci.nsIPrivateBrowsingService);
}
catch (ex) {
return null;
}
});
var EXPORTED_SYMBOLS = ["ConsoleAPIStorage"];
var _consoleStorage = {};
/**
* The ConsoleAPIStorage is meant to cache window.console API calls for later
* reuse by other components when needed. For example, the Web Console code can
* display the cached messages when it opens for the active tab.
*
* ConsoleAPI messages are stored as they come from the ConsoleAPI code, with
* all their properties. They are kept around until the inner window object that
* created the messages is destroyed. Messages are indexed by the inner window
* ID.
*
* Usage:
* Cu.import("resource://gre/modules/ConsoleAPIStorage.jsm");
*
* // Get the cached events array for the window you want (use the inner
* // window ID).
* let events = ConsoleAPIStorage.getEvents(innerWindowID);
* events.forEach(function(event) { ... });
*
* // Clear the events for the given inner window ID.
* ConsoleAPIStorage.clearEvents(innerWindowID);
*/
var ConsoleAPIStorage = {
QueryInterface: XPCOMUtils.generateQI([Ci.nsIObserver]),
/** @private */
observe: function CS_observe(aSubject, aTopic, aData)
{
if (aTopic == "xpcom-shutdown") {
Services.obs.removeObserver(this, "xpcom-shutdown");
Services.obs.removeObserver(this, "inner-window-destroyed");
Services.obs.removeObserver(this, "memory-pressure");
delete _consoleStorage;
}
else if (aTopic == "inner-window-destroyed") {
let innerWindowID = aSubject.QueryInterface(Ci.nsISupportsPRUint64).data;
this.clearEvents(innerWindowID);
}
else if (aTopic == "memory-pressure") {
if (aData == "low-memory") {
this.clearEvents();
}
}
},
/** @private */
init: function CS_init()
{
Services.obs.addObserver(this, "xpcom-shutdown", false);
Services.obs.addObserver(this, "inner-window-destroyed", false);
Services.obs.addObserver(this, "memory-pressure", false);
},
/**
* Get the events array by inner window ID.
*
* @param string aId
* The inner window ID for which you want to get the array of cached
* events.
* @returns array
* The array of cached events for the given window.
*/
getEvents: function CS_getEvents(aId)
{
return _consoleStorage[aId] || [];
},
/**
* Record an event associated with the given window ID.
*
* @param string aWindowID
* The ID of the inner window for which the event occurred.
* @param object aEvent
* A JavaScript object you want to store.
*/
recordEvent: function CS_recordEvent(aWindowID, aEvent)
{
let ID = parseInt(aWindowID);
if (isNaN(ID)) {
throw new Error("Invalid window ID argument");
}
if (gPrivBrowsing && gPrivBrowsing.privateBrowsingEnabled) {
return;
}
if (!_consoleStorage[ID]) {
_consoleStorage[ID] = [];
}
let storage = _consoleStorage[ID];
storage.push(aEvent);
// truncate
if (storage.length > STORAGE_MAX_EVENTS) {
storage.shift();
}
Services.obs.notifyObservers(aEvent, "console-storage-cache-event", ID);
},
/**
* Clear storage data for the given window.
*
* @param string [aId]
* Optional, the inner window ID for which you want to clear the
* messages. If this is not specified all of the cached messages are
* cleared, from all window objects.
*/
clearEvents: function CS_clearEvents(aId)
{
if (aId != null) {
delete _consoleStorage[aId];
}
else {
_consoleStorage = {};
Services.obs.notifyObservers(null, "console-storage-reset", null);
}
},
};
ConsoleAPIStorage.init();