diff options
Diffstat (limited to 'lib/private/legacy/eventsource.php')
| -rw-r--r-- | lib/private/legacy/eventsource.php | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/lib/private/legacy/eventsource.php b/lib/private/legacy/eventsource.php new file mode 100644 index 00000000000..f567d1e6ca5 --- /dev/null +++ b/lib/private/legacy/eventsource.php @@ -0,0 +1,125 @@ +<?php +/** + * @author Bart Visscher <bartv@thisnet.nl> + * @author Felix Moeller <mail@felixmoeller.de> + * @author Lukas Reschke <lukas@owncloud.com> + * @author Morris Jobke <hey@morrisjobke.de> + * @author Robin Appelman <icewind@owncloud.com> + * @author Thomas Müller <thomas.mueller@tmit.eu> + * @author Vincent Petry <pvince81@owncloud.com> + * + * @copyright Copyright (c) 2016, ownCloud, Inc. + * @license AGPL-3.0 + * + * This code is free software: you can redistribute it and/or modify + * it under the terms of the GNU Affero General Public License, version 3, + * as published by the Free Software Foundation. + * + * This program 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, version 3, + * along with this program. 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 caution, to many open requests can hang the server + */ +class OC_EventSource implements \OCP\IEventSource { + /** + * @var bool + */ + private $fallback; + + /** + * @var int + */ + private $fallBackId = 0; + + /** + * @var bool + */ + private $started = false; + + protected function init() { + if ($this->started) { + return; + } + $this->started = true; + + // prevent php output buffering, caching and nginx buffering + OC_Util::obEnd(); + header('Cache-Control: no-cache'); + header('X-Accel-Buffering: no'); + $this->fallback = isset($_GET['fallback']) and $_GET['fallback'] == 'true'; + if ($this->fallback) { + $this->fallBackId = (int)$_GET['fallback_id']; + /** + * FIXME: The default content-security-policy of ownCloud forbids inline + * JavaScript for security reasons. IE starting on Windows 10 will + * however also obey the CSP which will break the event source fallback. + * + * As a workaround thus we set a custom policy which allows the execution + * of inline JavaScript. + * + * @link https://github.com/owncloud/core/issues/14286 + */ + header("Content-Security-Policy: default-src 'none'; script-src 'unsafe-inline'"); + 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::$server->getRequest()->passesCSRFCheck())) { + $this->send('error', 'Possible CSRF attack. Connection will be closed.'); + $this->close(); + exit(); + } + flush(); + } + + /** + * send a message to the client + * + * @param string $type + * @param mixed $data + * + * @throws \BadMethodCallException + * if only one parameter is given, a typeless message will be send with that parameter as data + */ + public function send($type, $data = null) { + if ($data and !preg_match('/^[A-Za-z0-9_]+$/', $type)) { + throw new BadMethodCallException('Type needs to be alphanumeric ('. $type .')'); + } + $this->init(); + if (is_null($data)) { + $data = $type; + $type = null; + } + if ($this->fallback) { + $response = '<script type="text/javascript">window.parent.OC.EventSource.fallBackCallBack(' + . $this->fallBackId . ',"' . $type . '",' . OCP\JSON::encode($data) . ')</script>' . PHP_EOL; + echo $response; + } else { + if ($type) { + echo 'event: ' . $type . PHP_EOL; + } + echo 'data: ' . OCP\JSON::encode($data) . PHP_EOL; + } + echo PHP_EOL; + flush(); + } + + /** + * close the connection of the event source + */ + public function close() { + $this->send('__internal__', 'close'); //server side closing can be an issue, let the client do it + } +} |