client-share-web/0.2.0/scripts/dispatch.js

82 строки
2.5 KiB
JavaScript

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1
*
* 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 Raindrop.
*
* The Initial Developer of the Original Code is
* Mozilla Messaging, Inc..
* Portions created by the Initial Developer are Copyright (C) 2009
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* */
/*jslint plusplus: false, indent: 2 */
/*global require: false, define: false, location: false, window: false */
"use strict";
/**
* A module that handles dispatching pub/sub topics, where the underlying
* dispatch is done by postMessage. This allows for chrome extensions
* to participate in the pub/sub via postMessage without having to
* participate in this particular module.
*/
define(['jquery'], function ($) {
var origin = location.protocol + "//" + location.host;
return {
sub: function (topic, callback, win, targetOrigin) {
win = win || window;
targetOrigin = targetOrigin || origin;
var func = function (evt) {
//Make sure message is from this page, or from the browser extension
//that wants to communicate information back to the page.
if (evt.origin === targetOrigin || evt.origin === 'chrome://browser') {
//Assume pub/sub has JSON data with properties named
//'topic' and 'data'.
try {
var message = JSON.parse(evt.data),
pubTopic = message.topic;
if (pubTopic && pubTopic === topic) {
callback(message.data);
}
} catch (e) {
//Just ignore messages that are not JSON. There are some, like
//the oauth_success messages
}
}
};
win.addEventListener('message', func, false);
//return the created function to allow unsubscribing
return func;
},
unsub: function (func, win) {
win = win || window;
win.removeEventListener('message', func, false);
},
pub: function (topic, data, win) {
win = win || window;
win.postMessage(JSON.stringify({
topic: topic,
data: data
}), origin);
}
};
});