https://inkcat.net/core/js/eventsource.js?v=6d25bec96e49ef1a9b467b2da740060b

1/**
2 * ownCloud
3 *
4 * @author Robin Appelman
5 * @copyright Copyright (c) 2012 Robin Appelman [email protected]
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
9 * License as published by the Free Software Foundation; either
10 * version 3 of the License, or any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
16 *
17 * You should have received a copy of the GNU Affero General Public
18 * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
19 *
20 */
21
22/**
23 * Wrapper for server side events
24 * (http://en.wikipedia.org/wiki/Server-sent_events)
25 * includes a fallback for older browsers and IE
26 *
27 * use server side events with caution, too many open requests can hang the
28 * server
29 */
30
31/* global EventSource */
32
33/**
34 * Create a new event source
35 * @param {string} src
36 * @param {object} [data] to be send as GET
37 *
38 * @constructs OC.EventSource
39 */
40OC.EventSource=function(src,data){
41	var dataStr='';
42	var name;
43	var joinChar;
44	this.typelessListeners=[];
45	this.closed = false;
46	this.listeners={};
47	if(data){
48		for(name in data){
49			dataStr+=name+'='+encodeURIComponent(data[name])+'&';
50		}
51	}
52	dataStr+='requesttoken='+encodeURIComponent(oc_requesttoken);
53	if(!this.useFallBack && typeof EventSource !== 'undefined'){
54		joinChar = '&';
55		if(src.indexOf('?') === -1) {
56			joinChar = '?';
57		}
58		this.source= new EventSource(src+joinChar+dataStr);
59		this.source.onmessage=function(e){
60			for(var i=0;i<this.typelessListeners.length;i++){
61				this.typelessListeners[i](JSON.parse(e.data));
62			}
63		}.bind(this);
64	}else{
65		var iframeId='oc_eventsource_iframe_'+OC.EventSource.iframeCount;
66		OC.EventSource.fallBackSources[OC.EventSource.iframeCount]=this;
67		this.iframe=$('<iframe/>');
68		this.iframe.attr('id',iframeId);
69		this.iframe.hide();
70
71		joinChar = '&';
72		if(src.indexOf('?') === -1) {
73			joinChar = '?';
74		}
75		this.iframe.attr('src',src+joinChar+'fallback=true&fallback_id='+OC.EventSource.iframeCount+'&'+dataStr);
76		$('body').append(this.iframe);
77		this.useFallBack=true;
78		OC.EventSource.iframeCount++;
79	}
80	//add close listener
81	this.listen('__internal__',function(data){
82		if(data === 'close'){
83			this.close();
84		}
85	}.bind(this));
86};
87OC.EventSource.fallBackSources=[];
88OC.EventSource.iframeCount=0;//number of fallback iframes
89OC.EventSource.fallBackCallBack=function(id,type,data){
90	OC.EventSource.fallBackSources[id].fallBackCallBack(type,data);
91};
92OC.EventSource.prototype={
93	typelessListeners:[],
94	iframe:null,
95	listeners:{},//only for fallback
96	useFallBack:false,
97	/**
98	 * Fallback callback for browsers that don't have the
99	 * native EventSource object.
100	 *
101	 * Calls the registered listeners.
102	 *
103	 * @private
104	 * @param {String} type event type
105	 * @param {Object} data received data
106	 */
107	fallBackCallBack:function(type,data){
108		var i;
109		// ignore messages that might appear after closing
110		if (this.closed) {
111			return;
112		}
113		if(type){
114			if (typeof this.listeners.done !== 'undefined') {
115				for(i=0;i<this.listeners[type].length;i++){
116					this.listeners[type][i](data);
117				}
118			}
119		}else{
120			for(i=0;i<this.typelessListeners.length;i++){
121				this.typelessListeners[i](data);
122			}
123		}
124	},
125	lastLength:0,//for fallback
126	/**
127	 * Listen to a given type of events.
128	 *
129	 * @param {String} type event type
130	 * @param {Function} callback event callback
131	 */
132	listen:function(type,callback){
133		if(callback && callback.call){
134
135			if(type){
136				if(this.useFallBack){
137					if(!this.listeners[type]){
138						this.listeners[type]=[];
139					}
140					this.listeners[type].push(callback);
141				}else{
142					this.source.addEventListener(type,function(e){
143						if (typeof e.data !== 'undefined') {
144							callback(JSON.parse(e.data));
145						} else {
146							callback('');
147						}
148					},false);
149				}
150			}else{
151				this.typelessListeners.push(callback);
152			}
153		}
154	},
155	/**
156	 * Closes this event source.
157	 */
158	close:function(){
159		this.closed = true;
160		if (typeof this.source !== 'undefined') {
161			this.source.close();
162		}
163	}
164};