system/libraries/Cache/drivers/Cache_memcached.php

   1 <?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
   2 /**
   3  * CodeIgniter
   4  *
   5  * An open source application development framework for PHP 4.3.2 or newer
   6  *
   7  * @package             CodeIgniter
   8  * @author              ExpressionEngine Dev Team
   9  * @copyright   Copyright (c) 2006 - 2012 EllisLab, Inc.
  10  * @license             http://codeigniter.com/user_guide/license.html
  11  * @link                http://codeigniter.com
  12  * @since               Version 2.0
  13  * @filesource
  14  */
  15
  16 // ------------------------------------------------------------------------
  17
  18 /**
  19  * CodeIgniter Memcached Caching Class
  20  *
  21  * @package             CodeIgniter
  22  * @subpackage  Libraries
  23  * @category    Core
  24  * @author              ExpressionEngine Dev Team
  25  * @link
  26  */
  27
  28 class CI_Cache_memcached extends CI_Driver {
  29
  30         private $_memcached;    // Holds the memcached object
  31
  32         protected $_memcache_conf       = array(
  33                                         'default' => array(
  34                                                 'default_host'          => '127.0.0.1',
  35                                                 'default_port'          => 11211,
  36                                                 'default_weight'        => 1
  37                                         )
  38                                 );
  39
  40         // ------------------------------------------------------------------------
  41
  42         /**
  43          * Fetch from cache
  44          *
  45          * @param       mixed           unique key id
  46          * @return      mixed           data on success/false on failure
  47          */
  48         public function get($id)
  49         {
  50                 $data = $this->_memcached->get($id);
  51
  52                 return (is_array($data)) ? $data[0] : FALSE;
  53         }
  54
  55         // ------------------------------------------------------------------------
  56
  57         /**
  58          * Save
  59          *
  60          * @param       string          unique identifier
  61          * @param       mixed           data being cached
  62          * @param       int                     time to live
  63          * @return      boolean         true on success, false on failure
  64          */
  65         public function save($id, $data, $ttl = 60)
  66         {
  67                 if (get_class($this->_memcached) == 'Memcached')
  68                 {
  69                         return $this->_memcached->set($id, array($data, time(), $ttl), $ttl);
  70                 }
  71                 else if (get_class($this->_memcached) == 'Memcache')
  72                 {
  73                         return $this->_memcached->set($id, array($data, time(), $ttl), 0, $ttl);
  74                 }
  75
  76                 return FALSE;
  77         }
  78
  79         // ------------------------------------------------------------------------
  80
  81         /**
  82          * Delete from Cache
  83          *
  84          * @param       mixed           key to be deleted.
  85          * @return      boolean         true on success, false on failure
  86          */
  87         public function delete($id)
  88         {
  89                 return $this->_memcached->delete($id);
  90         }
  91
  92         // ------------------------------------------------------------------------
  93
  94         /**
  95          * Clean the Cache
  96          *
  97          * @return      boolean         false on failure/true on success
  98          */
  99         public function clean()
 100         {
 101                 return $this->_memcached->flush();
 102         }
 103
 104         // ------------------------------------------------------------------------
 105
 106         /**
 107          * Cache Info
 108          *
 109          * @param       null            type not supported in memcached
 110          * @return      mixed           array on success, false on failure
 111          */
 112         public function cache_info($type = NULL)
 113         {
 114                 return $this->_memcached->getStats();
 115         }
 116
 117         // ------------------------------------------------------------------------
 118
 119         /**
 120          * Get Cache Metadata
 121          *
 122          * @param       mixed           key to get cache metadata on
 123          * @return      mixed           FALSE on failure, array on success.
 124          */
 125         public function get_metadata($id)
 126         {
 127                 $stored = $this->_memcached->get($id);
 128
 129                 if (count($stored) !== 3)
 130                 {
 131                         return FALSE;
 132                 }
 133
 134                 list($data, $time, $ttl) = $stored;
 135
 136                 return array(
 137                         'expire'        => $time + $ttl,
 138                         'mtime'         => $time,
 139                         'data'          => $data
 140                 );
 141         }
 142
 143         // ------------------------------------------------------------------------
 144
 145         /**
 146          * Setup memcached.
 147          */
 148         private function _setup_memcached()
 149         {
 150                 // Try to load memcached server info from the config file.
 151                 $CI =& get_instance();
 152                 if ($CI->config->load('memcached', TRUE, TRUE))
 153                 {
 154                         if (is_array($CI->config->config['memcached']))
 155                         {
 156                                 $this->_memcache_conf = NULL;
 157
 158                                 foreach ($CI->config->config['memcached'] as $name => $conf)
 159                                 {
 160                                         $this->_memcache_conf[$name] = $conf;
 161                                 }
 162                         }
 163                 }
 164
 165                 $this->_memcached = new Memcached();
 166
 167                 foreach ($this->_memcache_conf as $name => $cache_server)
 168                 {
 169                         if ( ! array_key_exists('hostname', $cache_server))
 170                         {
 171                                 $cache_server['hostname'] = $this->_default_options['default_host'];
 172                         }
 173
 174                         if ( ! array_key_exists('port', $cache_server))
 175                         {
 176                                 $cache_server['port'] = $this->_default_options['default_port'];
 177                         }
 178
 179                         if ( ! array_key_exists('weight', $cache_server))
 180                         {
 181                                 $cache_server['weight'] = $this->_default_options['default_weight'];
 182                         }
 183
 184                         $this->_memcached->addServer(
 185                                         $cache_server['hostname'], $cache_server['port'], $cache_server['weight']
 186                         );
 187                 }
 188         }
 189
 190         // ------------------------------------------------------------------------
 191
 192
 193         /**
 194          * Is supported
 195          *
 196          * Returns FALSE if memcached is not supported on the system.
 197          * If it is, we setup the memcached object & return TRUE
 198          */
 199         public function is_supported()
 200         {
 201                 if ( ! extension_loaded('memcached'))
 202                 {
 203                         log_message('error', 'The Memcached Extension must be loaded to use Memcached Cache.');
 204
 205                         return FALSE;
 206                 }
 207
 208                 $this->_setup_memcached();
 209                 return TRUE;
 210         }
 211
 212         // ------------------------------------------------------------------------
 213
 214 }
 215 // End Class
 216
 217 /* End of file Cache_memcached.php */
 218 /* Location: ./system/libraries/Cache/drivers/Cache_memcached.php */