diff options
Diffstat (limited to 'system/libraries/drivers/Cache/Memcache.php')
| -rw-r--r-- | system/libraries/drivers/Cache/Memcache.php | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/system/libraries/drivers/Cache/Memcache.php b/system/libraries/drivers/Cache/Memcache.php new file mode 100644 index 00000000..d801de9c --- /dev/null +++ b/system/libraries/drivers/Cache/Memcache.php @@ -0,0 +1,191 @@ +<?php defined('SYSPATH') OR die('No direct access allowed.'); +/** + * Memcache-based Cache driver. + * + * $Id: Memcache.php 4102 2009-03-19 12:55:54Z Shadowhand $ + * + * @package Cache + * @author Kohana Team + * @copyright (c) 2007-2008 Kohana Team + * @license http://kohanaphp.com/license.html + */ +class Cache_Memcache_Driver implements Cache_Driver { + + const TAGS_KEY = 'memcache_tags_array'; + + // Cache backend object and flags + protected $backend; + protected $flags; + + // Tags array + protected static $tags; + + // Have the tags been changed? + protected static $tags_changed = FALSE; + + public function __construct() + { + if ( ! extension_loaded('memcache')) + throw new Kohana_Exception('cache.extension_not_loaded', 'memcache'); + + $this->backend = new Memcache; + $this->flags = Kohana::config('cache_memcache.compression') ? MEMCACHE_COMPRESSED : FALSE; + + $servers = Kohana::config('cache_memcache.servers'); + + foreach ($servers as $server) + { + // Make sure all required keys are set + $server += array('host' => '127.0.0.1', 'port' => 11211, 'persistent' => FALSE); + + // Add the server to the pool + $this->backend->addServer($server['host'], $server['port'], (bool) $server['persistent']) + or Kohana::log('error', 'Cache: Connection failed: '.$server['host']); + } + + // Load tags + self::$tags = $this->backend->get(self::TAGS_KEY); + + if ( ! is_array(self::$tags)) + { + // Create a new tags array + self::$tags = array(); + + // Tags have been created + self::$tags_changed = TRUE; + } + } + + public function __destruct() + { + if (self::$tags_changed === TRUE) + { + // Save the tags + $this->backend->set(self::TAGS_KEY, self::$tags, $this->flags, 0); + + // Tags are now unchanged + self::$tags_changed = FALSE; + } + } + + public function find($tag) + { + if (isset(self::$tags[$tag]) AND $results = $this->backend->get(self::$tags[$tag])) + { + // Return all the found caches + return $results; + } + else + { + // No matching tags + return array(); + } + } + + public function get($id) + { + return (($return = $this->backend->get($id)) === FALSE) ? NULL : $return; + } + + public function set($id, $data, array $tags = NULL, $lifetime) + { + if ( ! empty($tags)) + { + // Tags will be changed + self::$tags_changed = TRUE; + + foreach ($tags as $tag) + { + // Add the id to each tag + self::$tags[$tag][$id] = $id; + } + } + + if ($lifetime !== 0) + { + // Memcache driver expects unix timestamp + $lifetime += time(); + } + + // Set a new value + return $this->backend->set($id, $data, $this->flags, $lifetime); + } + + public function delete($id, $tag = FALSE) + { + // Tags will be changed + self::$tags_changed = TRUE; + + if ($id === TRUE) + { + if ($status = $this->backend->flush()) + { + // Remove all tags, all items have been deleted + self::$tags = array(); + + // We must sleep after flushing, or overwriting will not work! + // @see http://php.net/manual/en/function.memcache-flush.php#81420 + sleep(1); + } + + return $status; + } + elseif ($tag === TRUE) + { + if (isset(self::$tags[$id])) + { + foreach (self::$tags[$id] as $_id) + { + // Delete each id in the tag + $this->backend->delete($_id); + } + + // Delete the tag + unset(self::$tags[$id]); + } + + return TRUE; + } + else + { + foreach (self::$tags as $tag => $_ids) + { + if (isset(self::$tags[$tag][$id])) + { + // Remove the id from the tags + unset(self::$tags[$tag][$id]); + } + } + + return $this->backend->delete($id); + } + } + + public function delete_expired() + { + // Tags will be changed + self::$tags_changed = TRUE; + + foreach (self::$tags as $tag => $_ids) + { + foreach ($_ids as $id) + { + if ( ! $this->backend->get($id)) + { + // This id has disappeared, delete it from the tags + unset(self::$tags[$tag][$id]); + } + } + + if (empty(self::$tags[$tag])) + { + // The tag no longer has any valid ids + unset(self::$tags[$tag]); + } + } + + // Memcache handles garbage collection internally + return TRUE; + } + +} // End Cache Memcache Driver |