gnu-social/plugins/Memcache/MemcachePlugin.php
Siebrand Mazeland 3bcff2fa86 Use profile->getBestName() instead of more complex i18n unfriendly construction.
Update translator documentation.
Number parameters where more than one is used.
L10n updates.
Update README file to break lines at or just before 80 characters.
Remove PHP4-ism "?>"
Update indentation.
Update whitespace.
2011-04-25 22:44:21 +02:00

251 lines
7.9 KiB
PHP

<?php
/**
* StatusNet - the distributed open-source microblogging tool
* Copyright (C) 2009, StatusNet, Inc.
*
* Plugin to implement cache interface for memcache
*
* PHP version 5
*
* 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 Cache
* @package StatusNet
* @author Evan Prodromou <evan@status.net>
* @copyright 2009 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/
*/
if (!defined('STATUSNET')) {
// This check helps protect against security problems;
// your code file can't be executed directly from the web.
exit(1);
}
/**
* A plugin to use memcache for the cache interface
*
* This used to be encoded as config-variable options in the core code;
* it's now broken out to a separate plugin. The same interface can be
* implemented by other plugins.
*
* @category Cache
* @package StatusNet
* @author Evan Prodromou <evan@status.net>
* @copyright 2009 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/
*/
class MemcachePlugin extends Plugin
{
static $cacheInitialized = false;
private $_conn = null;
public $servers = array('127.0.0.1;11211');
public $compressThreshold = 20480;
public $compressMinSaving = 0.2;
public $persistent = null;
public $defaultExpiry = 86400; // 24h
/**
* Initialize the plugin
*
* Note that onStartCacheGet() may have been called before this!
*
* @return boolean flag value
*/
function onInitializePlugin()
{
if (self::$cacheInitialized) {
$this->persistent = true;
} else {
// If we're a parent command-line process we need
// to be able to close out the connection after
// forking, so disable persistence.
//
// We'll turn it back on again the second time
// through which will either be in a child process,
// or a single-process script which is switching
// configurations.
$this->persistent = (php_sapi_name() == 'cli') ? false : true;
}
$this->_ensureConn();
self::$cacheInitialized = true;
return true;
}
/**
* Get a value associated with a key
*
* The value should have been set previously.
*
* @param string &$key in; Lookup key
* @param mixed &$value out; value associated with key
*
* @return boolean hook success
*/
function onStartCacheGet(&$key, &$value)
{
$this->_ensureConn();
$value = $this->_conn->get($key);
Event::handle('EndCacheGet', array($key, &$value));
return false;
}
/**
* Associate a value with a key
*
* @param string &$key in; Key to use for lookups
* @param mixed &$value in; Value to associate
* @param integer &$flag in; Flag empty or Cache::COMPRESSED
* @param integer &$expiry in; Expiry (passed through to Memcache)
* @param boolean &$success out; Whether the set was successful
*
* @return boolean hook success
*/
function onStartCacheSet(&$key, &$value, &$flag, &$expiry, &$success)
{
$this->_ensureConn();
if ($expiry === null) {
$expiry = $this->defaultExpiry;
}
$success = $this->_conn->set($key, $value, $this->flag(intval($flag)), $expiry);
Event::handle('EndCacheSet', array($key, $value, $flag,
$expiry));
return false;
}
/**
* Atomically increment an existing numeric key value.
* Existing expiration time will not be changed.
*
* @param string &$key in; Key to use for lookups
* @param int &$step in; Amount to increment (default 1)
* @param mixed &$value out; Incremented value, or false if key not set.
*
* @return boolean hook success
*/
function onStartCacheIncrement(&$key, &$step, &$value)
{
$this->_ensureConn();
$value = $this->_conn->increment($key, $step);
Event::handle('EndCacheIncrement', array($key, $step, $value));
return false;
}
/**
* Delete a value associated with a key
*
* @param string &$key in; Key to lookup
* @param boolean &$success out; whether it worked
*
* @return boolean hook success
*/
function onStartCacheDelete(&$key, &$success)
{
$this->_ensureConn();
$success = $this->_conn->delete($key);
Event::handle('EndCacheDelete', array($key));
return false;
}
function onStartCacheReconnect(&$success)
{
if (empty($this->_conn)) {
// nothing to do
return true;
}
if ($this->persistent) {
common_log(LOG_ERR, "Cannot close persistent memcached connection");
$success = false;
} else {
common_log(LOG_INFO, "Closing memcached connection");
$success = $this->_conn->close();
$this->_conn = null;
}
return false;
}
/**
* Ensure that a connection exists
*
* Checks the instance $_conn variable and connects
* if it is empty.
*
* @return void
*/
private function _ensureConn()
{
if (empty($this->_conn)) {
$this->_conn = new Memcache();
if (is_array($this->servers)) {
$servers = $this->servers;
} else {
$servers = array($this->servers);
}
foreach ($servers as $server) {
if (strpos($server, ';') !== false) {
list($host, $port) = explode(';', $server);
} else {
$host = $server;
$port = 11211;
}
$this->_conn->addServer($host, $port, $this->persistent);
}
// Compress items stored in the cache if they're over threshold in size
// (default 2KiB) and the compression would save more than min savings
// ratio (default 0.2).
// Allows the cache to store objects larger than 1MB (if they
// compress to less than 1MB), and improves cache memory efficiency.
$this->_conn->setCompressThreshold($this->compressThreshold,
$this->compressMinSaving);
}
}
/**
* Translate general flags to Memcached-specific flags
* @param int $flag
* @return int
*/
protected function flag($flag)
{
$out = 0;
if ($flag & Cache::COMPRESSED == Cache::COMPRESSED) {
$out |= MEMCACHE_COMPRESSED;
}
return $out;
}
function onPluginVersion(&$versions)
{
$versions[] = array('name' => 'Memcache',
'version' => STATUSNET_VERSION,
'author' => 'Evan Prodromou, Craig Andrews',
'homepage' => 'http://status.net/wiki/Plugin:Memcache',
'rawdescription' =>
// TRANS: Plugin description.
_m('Use <a href="http://memcached.org/">Memcached</a> to cache query results.'));
return true;
}
}