3 * StatusNet - the distributed open-source microblogging tool
4 * Copyright (C) 2009, StatusNet, Inc.
6 * Plugin to implement cache interface for memcache
10 * This program is free software: you can redistribute it and/or modify
11 * it under the terms of the GNU Affero General Public License as published by
12 * the Free Software Foundation, either version 3 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU Affero General Public License for more details.
20 * You should have received a copy of the GNU Affero General Public License
21 * along with this program. If not, see <http://www.gnu.org/licenses/>.
25 * @author Evan Prodromou <evan@status.net>
26 * @copyright 2009 StatusNet, Inc.
27 * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
28 * @link http://status.net/
31 if (!defined('STATUSNET')) {
32 // This check helps protect against security problems;
33 // your code file can't be executed directly from the web.
38 * A plugin to use memcache for the cache interface
40 * This used to be encoded as config-variable options in the core code;
41 * it's now broken out to a separate plugin. The same interface can be
42 * implemented by other plugins.
46 * @author Evan Prodromou <evan@status.net>
47 * @copyright 2009 StatusNet, Inc.
48 * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
49 * @link http://status.net/
52 class MemcachePlugin extends Plugin
54 private $_conn = null;
55 public $servers = array('127.0.0.1;11211');
58 * Initialize the plugin
60 * Note that onStartCacheGet() may have been called before this!
62 * @return boolean flag value
65 function onInitializePlugin()
72 * Get a value associated with a key
74 * The value should have been set previously.
76 * @param string &$key in; Lookup key
77 * @param mixed &$value out; value associated with key
79 * @return boolean hook success
82 function onStartCacheGet(&$key, &$value)
85 $value = $this->_conn->get($key);
86 Event::handle('EndCacheGet', array($key, &$value));
91 * Associate a value with a key
93 * @param string &$key in; Key to use for lookups
94 * @param mixed &$value in; Value to associate
95 * @param integer &$flag in; Flag (passed through to Memcache)
96 * @param integer &$expiry in; Expiry (passed through to Memcache)
97 * @param boolean &$success out; Whether the set was successful
99 * @return boolean hook success
102 function onStartCacheSet(&$key, &$value, &$flag, &$expiry, &$success)
104 $this->_ensureConn();
105 $success = $this->_conn->set($key, $value, $flag, $expiry);
106 Event::handle('EndCacheSet', array($key, $value, $flag,
112 * Delete a value associated with a key
114 * @param string &$key in; Key to lookup
115 * @param boolean &$success out; whether it worked
117 * @return boolean hook success
120 function onStartCacheDelete(&$key, &$success)
122 $this->_ensureConn();
123 $success = $this->_conn->delete($key);
124 Event::handle('EndCacheDelete', array($key));
129 * Ensure that a connection exists
131 * Checks the instance $_conn variable and connects
137 private function _ensureConn()
139 if (empty($this->_conn)) {
140 $this->_conn = new Memcache();
142 if (is_array($this->servers)) {
143 foreach ($this->servers as $server) {
144 list($host, $port) = explode(';', $server);
149 $this->_conn->addServer($host, $port);
152 $this->_conn->addServer($this->servers);
153 list($host, $port) = explode(';', $this->servers);
157 $this->_conn->addServer($host, $port);
159 //Compress items stored in the cache if they're over 2k in size
160 //and the compression would save more than 20%.
161 //Allows the cache to store objects larger than 1MB (if they
162 //compress to less than 1MB), and improves cache memory efficiency.
163 $this->_conn->setCompressThreshold(20000, 0.2);