gnu-social/lib/queuemanager.php
Brion Vibber 26fdf0c9d2 XMPP queued output & initial retooling of DB queue manager to support non-Notice objects.
Queue handlers for XMPP individual & firehose output now send their XML stanzas
to another output queue instead of connecting directly to the chat server. This
lets us have as many general processing threads as we need, while all actual
XMPP input and output go through a single daemon with a single connection open.

This avoids problems with multiple connected resources:
* multiple windows shown in some chat clients (psi, gajim, kopete)
* extra load on server
* incoming message delivery forwarding issues

Database changes:
* queue_item drops 'notice_id' in favor of a 'frame' blob.
  This is based on Craig Andrews' work branch to generalize queues to take any
  object, but conservatively leaving out the serialization for now.
  Table updater (preserves any existing queued items) in db/rc3to09.sql

Code changes to watch out for:
* Queue handlers should now define a handle() method instead of handle_notice()
* QueueDaemon and XmppDaemon now share common i/o (IoMaster) and respawning
  thread management (RespawningDaemon) infrastructure.
* The polling XmppConfirmManager has been dropped, as the message is queued
  directly when saving IM settings.
* Enable $config['queue']['debug_memory'] to output current memory usage at
  each run through the event loop to watch for memory leaks

To do:
* Adapt XMPP i/o to component connection mode for multi-site support.
* XMPP input can also be broken out to a queue, which would allow the actual
  notice save etc to be handled by general queue threads.
* Make sure there are no problems with simply pushing serialized Notice objects
  to queues.
* Find a way to improve interactive performance of the database-backed queue
  handler; polling is pretty painful to XMPP.
* Possibly redo the way QueueHandlers are injected into a QueueManager. The
  grouping used to split out the XMPP output queue is a bit awkward.
2010-01-21 16:42:50 -08:00

291 lines
8.5 KiB
PHP

<?php
/**
* StatusNet, the distributed open-source microblogging tool
*
* Abstract class for i/o managers
*
* PHP version 5
*
* LICENCE: This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* 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
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* @category QueueManager
* @package StatusNet
* @author Evan Prodromou <evan@status.net>
* @author Sarven Capadisli <csarven@status.net>
* @author Brion Vibber <brion@status.net>
* @copyright 2009-2010 StatusNet, Inc.
* @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
* @link http://status.net/
*/
/**
* Completed child classes must implement the enqueue() method.
*
* For background processing, classes should implement either socket-based
* input (handleInput(), getSockets()) or idle-loop polling (idle()).
*/
abstract class QueueManager extends IoManager
{
static $qm = null;
public $master = null;
public $handlers = array();
public $groups = array();
/**
* Factory function to pull the appropriate QueueManager object
* for this site's configuration. It can then be used to queue
* events for later processing or to spawn a processing loop.
*
* Plugins can add to the built-in types by hooking StartNewQueueManager.
*
* @return QueueManager
*/
public static function get()
{
if (empty(self::$qm)) {
if (Event::handle('StartNewQueueManager', array(&self::$qm))) {
$enabled = common_config('queue', 'enabled');
$type = common_config('queue', 'subsystem');
if (!$enabled) {
// does everything immediately
self::$qm = new UnQueueManager();
} else {
switch ($type) {
case 'db':
self::$qm = new DBQueueManager();
break;
case 'stomp':
self::$qm = new StompQueueManager();
break;
default:
throw new ServerException("No queue manager class for type '$type'");
}
}
}
}
return self::$qm;
}
/**
* @fixme wouldn't necessarily work with other class types.
* Better to change the interface...?
*/
public static function multiSite()
{
if (common_config('queue', 'subsystem') == 'stomp') {
return IoManager::INSTANCE_PER_PROCESS;
} else {
return IoManager::SINGLE_ONLY;
}
}
function __construct()
{
$this->initialize();
}
/**
* Store an object (usually/always a Notice) into the given queue
* for later processing. No guarantee is made on when it will be
* processed; it could be immediately or at some unspecified point
* in the future.
*
* Must be implemented by any queue manager.
*
* @param Notice $object
* @param string $queue
*/
abstract function enqueue($object, $queue);
/**
* Build a representation for an object for logging
* @param mixed
* @return string
*/
function logrep($object) {
if (is_object($object)) {
$class = get_class($object);
if (isset($object->id)) {
return "$class $object->id";
}
return $class;
}
if (is_string($object)) {
$len = strlen($object);
$fragment = mb_substr($object, 0, 32);
if (mb_strlen($object) > 32) {
$fragment .= '...';
}
return "string '$fragment' ($len bytes)";
}
return strval($object);
}
/**
* Encode an object for queued storage.
* Next gen may use serialization.
*
* @param mixed $object
* @return string
*/
protected function encode($object)
{
if ($object instanceof Notice) {
return $object->id;
} else if (is_string($object)) {
return $object;
} else {
throw new ServerException("Can't queue this type", 500);
}
}
/**
* Decode an object from queued storage.
* Accepts back-compat notice reference entries and strings for now.
*
* @param string
* @return mixed
*/
protected function decode($frame)
{
if (is_numeric($frame)) {
return Notice::staticGet(intval($frame));
} else {
return $frame;
}
}
/**
* Instantiate the appropriate QueueHandler class for the given queue.
*
* @param string $queue
* @return mixed QueueHandler or null
*/
function getHandler($queue)
{
if (isset($this->handlers[$queue])) {
$class = $this->handlers[$queue];
if (class_exists($class)) {
return new $class();
} else {
common_log(LOG_ERR, "Nonexistent handler class '$class' for queue '$queue'");
}
} else {
common_log(LOG_ERR, "Requested handler for unkown queue '$queue'");
}
return null;
}
/**
* Get a list of registered queue transport names to be used
* for this daemon.
*
* @return array of strings
*/
function getQueues()
{
$group = $this->activeGroup();
return array_keys($this->groups[$group]);
}
/**
* Initialize the list of queue handlers
*
* @event StartInitializeQueueManager
* @event EndInitializeQueueManager
*/
function initialize()
{
// @fixme we'll want to be able to listen to particular queues...
if (Event::handle('StartInitializeQueueManager', array($this))) {
$this->connect('plugin', 'PluginQueueHandler');
$this->connect('omb', 'OmbQueueHandler');
$this->connect('ping', 'PingQueueHandler');
if (common_config('sms', 'enabled')) {
$this->connect('sms', 'SmsQueueHandler');
}
// XMPP output handlers...
$this->connect('jabber', 'JabberQueueHandler');
$this->connect('public', 'PublicQueueHandler');
// @fixme this should get an actual queue
//$this->connect('confirm', 'XmppConfirmHandler');
// For compat with old plugins not registering their own handlers.
$this->connect('plugin', 'PluginQueueHandler');
$this->connect('xmppout', 'XmppOutQueueHandler', 'xmppdaemon');
}
Event::handle('EndInitializeQueueManager', array($this));
}
/**
* Register a queue transport name and handler class for your plugin.
* Only registered transports will be reliably picked up!
*
* @param string $transport
* @param string $class
* @param string $group
*/
public function connect($transport, $class, $group='queuedaemon')
{
$this->handlers[$transport] = $class;
$this->groups[$group][$transport] = $class;
}
/**
* @return string queue group to use for this request
*/
function activeGroup()
{
$group = 'queuedaemon';
if ($this->master) {
// hack hack
if ($this->master instanceof XmppMaster) {
return 'xmppdaemon';
}
}
return $group;
}
/**
* Send a statistic ping to the queue monitoring system,
* optionally with a per-queue id.
*
* @param string $key
* @param string $queue
*/
function stats($key, $queue=false)
{
$owners = array();
if ($queue) {
$owners[] = "queue:$queue";
$owners[] = "site:" . common_config('site', 'server');
}
if (isset($this->master)) {
$this->master->stats($key, $owners);
} else {
$monitor = new QueueMonitor();
$monitor->stats($key, $owners);
}
}
}