gecko/services/sync/modules/trackers.js
Edward Lee d4295ef8e9 Remove unused prefs and imports. (Bug 524916)
--HG--
extra : rebase_source : 074e542f63ee840b61db7fe63a6c3540c13a31a5
2009-11-25 17:49:15 -08:00

181 lines
5.6 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 Bookmarks Sync.
*
* The Initial Developer of the Original Code is Mozilla.
* Portions created by the Initial Developer are Copyright (C) 2008
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Anant Narayanan <anant@kix.in>
*
* 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 ***** */
const EXPORTED_SYMBOLS = ['Tracker'];
const Cc = Components.classes;
const Ci = Components.interfaces;
const Cr = Components.results;
const Cu = Components.utils;
Cu.import("resource://weave/log4moz.js");
Cu.import("resource://weave/constants.js");
Cu.import("resource://weave/util.js");
Cu.import("resource://weave/ext/Observers.js");
/*
* Trackers are associated with a single engine and deal with
* listening for changes to their particular data type.
*
* There are two things they keep track of:
* 1) A score, indicating how urgently the engine wants to sync
* 2) A list of IDs for all the changed items that need to be synced
* and updating their 'score', indicating how urgently they
* want to sync.
*
*/
function Tracker() {
this._init();
}
Tracker.prototype = {
_logName: "Tracker",
file: "none",
_init: function T__init() {
this._log = Log4Moz.repository.getLogger(this._logName);
let level = Svc.Prefs.get("log.logger.engine." + this.name, "Debug");
this._log.level = Log4Moz.Level[level];
this._score = 0;
this._ignored = [];
this.ignoreAll = false;
this.loadChangedIDs();
},
/*
* Score can be called as often as desired to decide which engines to sync
*
* Valid values for score:
* -1: Do not sync unless the user specifically requests it (almost disabled)
* 0: Nothing has changed
* 100: Please sync me ASAP!
*
* Setting it to other values should (but doesn't currently) throw an exception
*/
get score() {
return this._score;
},
set score(value) {
this._score = value;
Observers.notify("weave:engine:score:updated", this.name);
},
// Should be called by service everytime a sync has been done for an engine
resetScore: function T_resetScore() {
this._score = 0;
},
/*
* Changed IDs are in an object (hash) to make it easy to check if
* one is already set or not.
* Note that it would be nice to make these methods asynchronous so
* as to not block when writing to disk. However, these will often
* get called from observer callbacks, and so it is better to make
* them synchronous.
*/
get changedIDs() {
let items = {};
this.__defineGetter__("changedIDs", function() items);
return items;
},
saveChangedIDs: function T_saveChangedIDs() {
Utils.jsonSave("changes/" + this.file, this, this.changedIDs);
},
loadChangedIDs: function T_loadChangedIDs() {
Utils.jsonLoad("changes/" + this.file, this, function(json) {
for (let id in json)
this.changedIDs[id] = 1;
});
},
// ignore/unignore specific IDs. Useful for ignoring items that are
// being processed, or that shouldn't be synced.
// But note: not persisted to disk
ignoreID: function T_ignoreID(id) {
this.unignoreID(id);
this._ignored.push(id);
},
unignoreID: function T_unignoreID(id) {
let index = this._ignored.indexOf(id);
if (index != -1)
this._ignored.splice(index, 1);
},
addChangedID: function T_addChangedID(id) {
if (!id) {
this._log.warn("Attempted to add undefined ID to tracker");
return false;
}
if (this.ignoreAll || (id in this._ignored))
return false;
if (!this.changedIDs[id]) {
this._log.trace("Adding changed ID " + id);
this.changedIDs[id] = true;
this.saveChangedIDs();
}
return true;
},
removeChangedID: function T_removeChangedID(id) {
if (!id) {
this._log.warn("Attempted to remove undefined ID to tracker");
return false;
}
if (this.ignoreAll || (id in this._ignored))
return false;
if (this.changedIDs[id]) {
this._log.trace("Removing changed ID " + id);
delete this.changedIDs[id];
this.saveChangedIDs();
}
return true;
},
clearChangedIDs: function T_clearChangedIDs() {
this._log.trace("Clearing changed ID list");
for (let id in this.changedIDs) {
delete this.changedIDs[id];
}
this.saveChangedIDs();
}
};