gnu-social/lib/queuemanager.php
2021-07-16 19:44:33 +01:00

380 lines
12 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;
protected $master = null;
protected $handlers = array();
protected $groups = array();
protected $activeGroups = array();
protected $ignoredTransports = array();
/**
* Factory function to pull the appropriate QueueManager object
* for this site's configuration. It can then be used to queue
* events for later processing or to spawn a processing loop.
*
* Plugins can add to the built-in types by hooking StartNewQueueManager.
*
* @return QueueManager
*/
public static function get()
{
if (empty(self::$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();
}
/**
* Optional; ping any running queue handler daemons with a notification
* such as announcing a new site to handle or requesting clean shutdown.
* This avoids having to restart all the daemons manually to update configs
* and such.
*
* Called from scripts/queuectl.php controller utility.
*
* @param string $event event key
* @param string $param optional parameter to append to key
* @return boolean success
*/
public function sendControlSignal($event, $param='')
{
throw new Exception(get_class($this) . " does not support control signals.");
}
/**
* 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 $class;
} elseif (is_string($object)) {
$len = strlen($object);
$fragment = mb_substr($object, 0, 32);
if (mb_strlen($object) > 32) {
$fragment .= '...';
}
return "string '$fragment' ($len bytes)";
} elseif (is_array($object)) {
return 'array with ' . count($object) .
' elements (keys:[' . implode(',', array_keys($object)) . '])';
}
return strval($object);
}
/**
* Encode an object for queued storage.
*
* @param mixed $item
* @return string
*/
protected function encode($item)
{
return serialize($item);
}
/**
* Decode an object from queued storage.
* Accepts notice reference entries and serialized items.
*
* @param string
* @return mixed
*/
protected function decode($frame)
{
$object = unserialize($frame);
// If it is a string, we really store a JSON object in there
// except if it begins with '<', because then it is XML.
if (is_string($object) &&
substr($object, 0, 1) != '<' &&
!is_numeric($object))
{
$json = json_decode($object);
if ($json === null) {
throw new Exception('Bad frame in queue item');
}
// The JSON object has a type parameter which contains the class
if (empty($json->type)) {
throw new Exception('Type not specified for queue item');
}
if (!is_a($json->type, 'Managed_DataObject', true)) {
throw new Exception('Managed_DataObject class does not exist for queue item');
}
// And each of these types should have a unique id (or uri)
if (isset($json->id) && !empty($json->id)) {
$object = call_user_func(array($json->type, 'getKV'), 'id', $json->id);
} elseif (isset($json->uri) && !empty($json->uri)) {
$object = call_user_func(array($json->type, 'getKV'), 'uri', $json->uri);
}
// But if no object was found, there's nothing we can handle
if (!$object instanceof Managed_DataObject) {
throw new Exception('Queue item frame referenced a non-existant object');
}
}
// If the frame was not a string, it's either an array or an object.
return $object;
}
/**
* 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(is_object($class)) {
return $class;
} else if (class_exists($class)) {
return new $class();
} else {
$this->_log(LOG_ERR, "Nonexistent handler class '$class' for queue '$queue'");
}
}
throw new NoQueueHandlerException($queue);
}
/**
* Get a list of registered queue transport names to be used
* for listening in this daemon.
*
* @return array of strings
*/
function activeQueues()
{
$queues = array();
foreach ($this->activeGroups as $group) {
if (isset($this->groups[$group])) {
$queues = array_merge($queues, $this->groups[$group]);
}
}
return array_keys($queues);
}
function getIgnoredTransports()
{
return array_keys($this->ignoredTransports);
}
function ignoreTransport($transport)
{
// key is used for uniqueness, value doesn't mean anything
$this->ignoredTransports[$transport] = true;
}
/**
* Initialize the list of queue handlers for the current site.
*
* @event StartInitializeQueueManager
* @event EndInitializeQueueManager
*/
function initialize()
{
$this->handlers = array();
$this->groups = array();
$this->groupsByTransport = array();
if (Event::handle('StartInitializeQueueManager', array($this))) {
$this->connect('distrib', 'DistribQueueHandler');
$this->connect('ping', 'PingQueueHandler');
if (common_config('sms', 'enabled')) {
$this->connect('sms', 'SmsQueueHandler');
}
// Background user management tasks...
$this->connect('deluser', 'DelUserQueueHandler');
$this->connect('feedimp', 'FeedImporter');
$this->connect('actimp', 'ActivityImporter');
$this->connect('acctmove', 'AccountMover');
$this->connect('actmove', 'ActivityMover');
// For compat with old plugins not registering their own handlers.
$this->connect('Module', 'ModuleQueueHandler');
}
Event::handle('EndInitializeQueueManager', array($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 class name or object instance
* @param string $group
*/
public function connect($transport, $class, $group='main')
{
$this->handlers[$transport] = $class;
$this->groups[$group][$transport] = $class;
$this->groupsByTransport[$transport] = $group;
}
/**
* Set the active group which will be used for listening.
* @param string $group
*/
function setActiveGroup($group)
{
$this->activeGroups = array($group);
}
/**
* Set the active group(s) which will be used for listening.
* @param array $groups
*/
function setActiveGroups($groups)
{
$this->activeGroups = $groups;
}
/**
* @return string queue group for this queue
*/
function queueGroup($queue)
{
if (isset($this->groupsByTransport[$queue])) {
return $this->groupsByTransport[$queue];
} else {
throw new Exception("Requested group for unregistered transport $queue");
}
}
/**
* 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, $owners);
}
}
protected function _log($level, $msg)
{
$class = get_class($this);
if ($this->activeGroups) {
$groups = ' (' . implode(',', $this->activeGroups) . ')';
} else {
$groups = '';
}
common_log($level, "$class$groups: $msg");
}
}