.
*
*/
/**
* 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 caution, 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(''.PHP_EOL, 10); //dummy data to keep IE happy
}else{
header("Content-Type: text/event-stream");
}
if( !OC_Util::isCallRegistered()) {
$this->send('error', 'Possible CSRF attack. Connection will be closed.');
exit();
}
flush();
}
/**
* send a message to the client
* @param string $type
* @param object $data
*
* if only one parameter is given, a typeless message will be send with that parameter as data
*/
public function send($type, $data=null) {
if(is_null($data)) {
$data=$type;
$type=null;
}
if($this->fallback) {
$response=''.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
}
}