3 * StatusNet, the distributed open-source microblogging tool
5 * Abstract class for i/o managers
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16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU Affero General Public License for more details.
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22 * @category QueueManager
24 * @author Evan Prodromou <evan@status.net>
25 * @author Sarven Capadisli <csarven@status.net>
26 * @author Brion Vibber <brion@status.net>
27 * @copyright 2009-2010 StatusNet, Inc.
28 * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
29 * @link http://status.net/
33 * Completed child classes must implement the enqueue() method.
35 * For background processing, classes should implement either socket-based
36 * input (handleInput(), getSockets()) or idle-loop polling (idle()).
38 abstract class QueueManager extends IoManager
42 protected $master = null;
43 protected $handlers = array();
44 protected $groups = array();
45 protected $activeGroups = array();
48 * Factory function to pull the appropriate QueueManager object
49 * for this site's configuration. It can then be used to queue
50 * events for later processing or to spawn a processing loop.
52 * Plugins can add to the built-in types by hooking StartNewQueueManager.
54 * @return QueueManager
56 public static function get()
58 if (empty(self::$qm)) {
60 if (Event::handle('StartNewQueueManager', array(&self::$qm))) {
62 $enabled = common_config('queue', 'enabled');
63 $type = common_config('queue', 'subsystem');
66 // does everything immediately
67 self::$qm = new UnQueueManager();
71 self::$qm = new OpportunisticQueueManager();
74 self::$qm = new DBQueueManager();
77 self::$qm = new StompQueueManager();
80 throw new ServerException("No queue manager class for type '$type'");
90 * @fixme wouldn't necessarily work with other class types.
91 * Better to change the interface...?
93 public static function multiSite()
95 if (common_config('queue', 'subsystem') == 'stomp') {
96 return IoManager::INSTANCE_PER_PROCESS;
98 return IoManager::SINGLE_ONLY;
102 function __construct()
108 * Optional; ping any running queue handler daemons with a notification
109 * such as announcing a new site to handle or requesting clean shutdown.
110 * This avoids having to restart all the daemons manually to update configs
113 * Called from scripts/queuectl.php controller utility.
115 * @param string $event event key
116 * @param string $param optional parameter to append to key
117 * @return boolean success
119 public function sendControlSignal($event, $param='')
121 throw new Exception(get_class($this) . " does not support control signals.");
125 * Store an object (usually/always a Notice) into the given queue
126 * for later processing. No guarantee is made on when it will be
127 * processed; it could be immediately or at some unspecified point
130 * Must be implemented by any queue manager.
132 * @param Notice $object
133 * @param string $queue
135 abstract function enqueue($object, $queue);
138 * Build a representation for an object for logging
142 function logrep($object) {
143 if (is_object($object)) {
144 $class = get_class($object);
145 if (isset($object->id)) {
146 return "$class $object->id";
149 } elseif (is_string($object)) {
150 $len = strlen($object);
151 $fragment = mb_substr($object, 0, 32);
152 if (mb_strlen($object) > 32) {
155 return "string '$fragment' ($len bytes)";
156 } elseif (is_array($object)) {
157 return 'array with ' . count($object) .
158 ' elements (keys:[' . implode(',', array_keys($object)) . '])';
160 return strval($object);
164 * Encode an object for queued storage.
169 protected function encode($item)
171 return serialize($item);
175 * Decode an object from queued storage.
176 * Accepts notice reference entries and serialized items.
181 protected function decode($frame)
183 $object = unserialize($frame);
185 // If it is a string, we really store a JSON object in there
186 if (is_string($object)) {
187 $json = json_decode($object);
188 if ($json === null) {
189 throw new Exception('Bad frame in queue item');
192 // The JSON object has a type parameter which contains the class
193 if (empty($json->type)) {
194 throw new Exception('Type not specified for queue item');
196 if (!is_a($json->type, 'Managed_DataObject', true)) {
197 throw new Exception('Managed_DataObject class does not exist for queue item');
200 // And each of these types should have a unique id (or uri)
201 if (isset($json->id) && !empty($json->id)) {
202 $object = call_user_func(array($json->type, 'getKV'), 'id', $json->id);
203 } elseif (isset($json->uri) && !empty($json->uri)) {
204 $object = call_user_func(array($json->type, 'getKV'), 'uri', $json->uri);
207 // But if no object was found, there's nothing we can handle
208 if (!$object instanceof Managed_DataObject) {
209 throw new Exception('Queue item frame referenced a non-existant object');
213 // If the frame was not a string, it's either an array or an object.
219 * Instantiate the appropriate QueueHandler class for the given queue.
221 * @param string $queue
222 * @return mixed QueueHandler or null
224 function getHandler($queue)
226 if (isset($this->handlers[$queue])) {
227 $class = $this->handlers[$queue];
228 if(is_object($class)) {
230 } else if (class_exists($class)) {
233 $this->_log(LOG_ERR, "Nonexistent handler class '$class' for queue '$queue'");
236 $this->_log(LOG_ERR, "Requested handler for unkown queue '$queue'");
242 * Get a list of registered queue transport names to be used
243 * for listening in this daemon.
245 * @return array of strings
247 function activeQueues()
250 foreach ($this->activeGroups as $group) {
251 if (isset($this->groups[$group])) {
252 $queues = array_merge($queues, $this->groups[$group]);
256 return array_keys($queues);
260 * Initialize the list of queue handlers for the current site.
262 * @event StartInitializeQueueManager
263 * @event EndInitializeQueueManager
265 function initialize()
267 $this->handlers = array();
268 $this->groups = array();
269 $this->groupsByTransport = array();
271 if (Event::handle('StartInitializeQueueManager', array($this))) {
272 $this->connect('distrib', 'DistribQueueHandler');
273 $this->connect('ping', 'PingQueueHandler');
274 if (common_config('sms', 'enabled')) {
275 $this->connect('sms', 'SmsQueueHandler');
278 // Background user management tasks...
279 $this->connect('deluser', 'DelUserQueueHandler');
280 $this->connect('feedimp', 'FeedImporter');
281 $this->connect('actimp', 'ActivityImporter');
282 $this->connect('acctmove', 'AccountMover');
283 $this->connect('actmove', 'ActivityMover');
285 // For compat with old plugins not registering their own handlers.
286 $this->connect('plugin', 'PluginQueueHandler');
288 Event::handle('EndInitializeQueueManager', array($this));
292 * Register a queue transport name and handler class for your plugin.
293 * Only registered transports will be reliably picked up!
295 * @param string $transport
296 * @param string $class class name or object instance
297 * @param string $group
299 public function connect($transport, $class, $group='main')
301 $this->handlers[$transport] = $class;
302 $this->groups[$group][$transport] = $class;
303 $this->groupsByTransport[$transport] = $group;
307 * Set the active group which will be used for listening.
308 * @param string $group
310 function setActiveGroup($group)
312 $this->activeGroups = array($group);
316 * Set the active group(s) which will be used for listening.
317 * @param array $groups
319 function setActiveGroups($groups)
321 $this->activeGroups = $groups;
325 * @return string queue group for this queue
327 function queueGroup($queue)
329 if (isset($this->groupsByTransport[$queue])) {
330 return $this->groupsByTransport[$queue];
332 throw new Exception("Requested group for unregistered transport $queue");
337 * Send a statistic ping to the queue monitoring system,
338 * optionally with a per-queue id.
341 * @param string $queue
343 function stats($key, $queue=false)
347 $owners[] = "queue:$queue";
348 $owners[] = "site:" . common_config('site', 'server');
350 if (isset($this->master)) {
351 $this->master->stats($key, $owners);
353 $monitor = new QueueMonitor();
354 $monitor->stats($key, $owners);
358 protected function _log($level, $msg)
360 $class = get_class($this);
361 if ($this->activeGroups) {
362 $groups = ' (' . implode(',', $this->activeGroups) . ')';
366 common_log($level, "$class$groups: $msg");