3 * Laconica, the distributed open-source microblogging tool
5 * Simple-minded queue manager for storing items in the database
9 * LICENCE: This program is free software: you can redistribute it and/or modify
10 * it under the terms of the GNU Affero General Public License as published by
11 * the Free Software Foundation, either version 3 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU Affero General Public License for more details.
19 * You should have received a copy of the GNU Affero General Public License
20 * along with this program. If not, see <http://www.gnu.org/licenses/>.
22 * @category QueueManager
24 * @author Evan Prodromou <evan@controlyourself.ca>
25 * @author Sarven Capadisli <csarven@controlyourself.ca>
26 * @copyright 2009 Control Yourself, Inc.
27 * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
28 * @link http://laconi.ca/
31 class DBQueueManager extends QueueManager
35 function enqueue($object, $queue)
39 $qi = new Queue_item();
41 $qi->notice_id = $notice->id;
42 $qi->transport = $queue;
43 $qi->created = $notice->created;
44 $result = $qi->insert();
47 common_log_db_error($qi, 'INSERT', __FILE__);
48 throw new ServerException('DB error inserting queue item');
54 function service($queue, $handler)
57 $this->_log(LOG_DEBUG, 'Checking for notices...');
58 $timeout = $handler->timeout();
59 $notice = $this->_nextItem($queue, $timeout);
61 $this->_log(LOG_DEBUG, 'No notices waiting; idling.');
62 // Nothing in the queue. Do you
63 // have other tasks, like servicing your
64 // XMPP connection, to do?
65 $handler->idle(QUEUE_HANDLER_MISS_IDLE);
67 $this->_log(LOG_INFO, 'Got notice '. $notice->id);
69 if ($handler->handle_notice($notice)) {
70 $this->_log(LOG_INFO, 'Successfully handled notice '. $notice->id);
71 $this->_done($notice, $queue);
73 $this->_log(LOG_INFO, 'Failed to handle notice '. $notice->id);
74 $this->_fail($notice, $queue);
76 // Chance to e.g. service your XMPP connection
77 $this->_log(LOG_DEBUG, 'Idling after success.');
78 $handler->idle(QUEUE_HANDLER_HIT_IDLE);
80 // XXX: when do we give up?
84 function _nextItem($queue, $timeout=null)
90 $qi = Queue_item::top($queue);
94 $notice = Notice::staticGet('id', $qi->notice_id);
95 if (!empty($notice)) {
98 $this->_log(LOG_INFO, 'dequeued non-existent notice ' . $notice->id);
104 } while (empty($result) && (is_null($timeout) || (time() - $start) < $timeout));
109 function _done($object, $queue)
111 // XXX: right now, we only handle notices
115 $qi = Queue_item::pkeyGet(array('notice_id' => $notice->id,
116 'transport' => $queue));
119 $this->_log(LOG_INFO, 'Cannot find queue item for notice '.$notice->id.', queue '.$queue);
121 if (empty($qi->claimed)) {
122 $this->_log(LOG_WARNING, 'Reluctantly releasing unclaimed queue item '.
123 'for '.$notice->id.', queue '.$queue);
130 $this->_log(LOG_INFO, 'done with notice ID = ' . $notice->id);
136 function _fail($object, $queue)
138 // XXX: right now, we only handle notices
142 $qi = Queue_item::pkeyGet(array('notice_id' => $notice->id,
143 'transport' => $queue));
146 $this->_log(LOG_INFO, 'Cannot find queue item for notice '.$notice->id.', queue '.$queue);
148 if (empty($qi->claimed)) {
149 $this->_log(LOG_WARNING, 'Ignoring failure for unclaimed queue item '.
150 'for '.$notice->id.', queue '.$queue);
159 $this->_log(LOG_INFO, 'done with notice ID = ' . $notice->id);
165 function _log($level, $msg)
167 common_log($level, 'DBQueueManager: '.$msg);