nextcloud/lib/eventsource.php

84 lines
2.3 KiB
PHP

<?php
/**
* ownCloud
*
* @author Robin Appelman
* @copyright 2012 Robin Appelman icewind1991@gmail.com
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
* License as published by the Free Software Foundation; either
* version 3 of the License, or any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU AFFERO GENERAL PUBLIC LICENSE for more details.
*
* You should have received a copy of the GNU Affero General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
*/
/**
* wrapper for server side events (http://en.wikipedia.org/wiki/Server-sent_events)
* includes a fallback for older browsers and IE
*
* use server side events with causion, to many open requests can hang the server
*/
class OC_EventSource{
private $fallback;
private $fallBackId=0;
public function __construct() {
OC_Util::obEnd();
header('Cache-Control: no-cache');
$this->fallback=isset($_GET['fallback']) and $_GET['fallback']=='true';
if($this->fallback) {
$this->fallBackId=$_GET['fallback_id'];
header("Content-Type: text/html");
echo str_repeat('<span></span>'.PHP_EOL,10); //dummy data to keep IE happy
}else{
header("Content-Type: text/event-stream");
}
if( !OC_Util::isCallRegistered()) {
exit();
}
flush();
}
/**
* send a message to the client
* @param string type
* @param object data
*
* if only one paramater is given, a typeless message will be send with that paramater as data
*/
public function send($type,$data=null) {
if(is_null($data)) {
$data=$type;
$type=null;
}
if($this->fallback) {
$response='<script type="text/javascript">window.parent.OC.EventSource.fallBackCallBack('.$this->fallBackId.',"'.$type.'",'.json_encode($data).')</script>'.PHP_EOL;
echo $response;
}else{
if($type) {
echo 'event: '.$type.PHP_EOL;
}
echo 'data: '.json_encode($data).PHP_EOL;
}
echo PHP_EOL;
flush();
}
/**
* close the connection of the even source
*/
public function close() {
$this->send('__internal__','close');//server side closing can be an issue, let the client do it
}
}