CRM/Utils/Cache/Memcached.php

   1 <?php
   2 /*
   3  +--------------------------------------------------------------------+
   4  | CiviCRM version 4.5                                                |
   5  +--------------------------------------------------------------------+
   6  | Copyright CiviCRM LLC (c) 2004-2014                                |
   7  +--------------------------------------------------------------------+
   8  | This file is a part of CiviCRM.                                    |
   9  |                                                                    |
  10  | CiviCRM is free software; you can copy, modify, and distribute it  |
  11  | under the terms of the GNU Affero General Public License           |
  12  | Version 3, 19 November 2007 and the CiviCRM Licensing Exception.   |
  13  |                                                                    |
  14  | CiviCRM is distributed in the hope that it will be useful, but     |
  15  | WITHOUT ANY WARRANTY; without even the implied warranty of         |
  16  | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.               |
  17  | See the GNU Affero General Public License for more details.        |
  18  |                                                                    |
  19  | You should have received a copy of the GNU Affero General Public   |
  20  | License and the CiviCRM Licensing Exception along                  |
  21  | with this program; if not, contact CiviCRM LLC                     |
  22  | at info[AT]civicrm[DOT]org. If you have questions about the        |
  23  | GNU Affero General Public License or the licensing of CiviCRM,     |
  24  | see the CiviCRM license FAQ at http://civicrm.org/licensing        |
  25  +--------------------------------------------------------------------+
  26 */
  27
  28 /**
  29  *
  30  * @package CRM
  31  * @copyright CiviCRM LLC (c) 2004-2014
  32  * $Id$
  33  *
  34  */
  35 class CRM_Utils_Cache_Memcached {
  36   const DEFAULT_HOST    = 'localhost';
  37   const DEFAULT_PORT    = 11211;
  38   const DEFAULT_TIMEOUT = 3600;
  39   const DEFAULT_PREFIX  = '';
  40   const MAX_KEY_LEN     = 62;
  41
  42   /**
  43    * The host name of the memcached server
  44    *
  45    * @var string
  46    */
  47   protected $_host = self::DEFAULT_HOST;
  48
  49   /**
  50    * The port on which to connect on
  51    *
  52    * @var int
  53    */
  54   protected $_port = self::DEFAULT_PORT;
  55
  56   /**
  57    * The default timeout to use
  58    *
  59    * @var int
  60    */
  61   protected $_timeout = self::DEFAULT_TIMEOUT;
  62
  63   /**
  64    * The prefix prepended to cache keys.
  65    *
  66    * If we are using the same memcache instance for multiple CiviCRM
  67    * installs, we must have a unique prefix for each install to prevent
  68    * the keys from clobbering each other.
  69    *
  70    * @var string
  71    */
  72   protected $_prefix = self::DEFAULT_PREFIX;
  73
  74   /**
  75    * The actual memcache object
  76    *
  77    * @var resource
  78    */
  79   protected $_cache;
  80
  81   /**
  82    * Constructor
  83    *
  84    * @param array   $config  an array of configuration params
  85    * @return void
  86    */
  87   function __construct($config) {
  88     if (isset($config['host'])) {
  89       $this->_host = $config['host'];
  90     }
  91     if (isset($config['port'])) {
  92       $this->_port = $config['port'];
  93     }
  94     if (isset($config['timeout'])) {
  95       $this->_timeout = $config['timeout'];
  96     }
  97     if (isset($config['prefix'])) {
  98       $this->_prefix = $config['prefix'];
  99     }
 100
 101     $this->_cache = new Memcached();
 102
 103     if (!$this->_cache->addServer($this->_host, $this->_port)) {
 104       // dont use fatal here since we can go in an infinite loop
 105       echo 'Could not connect to Memcached server';
 106       CRM_Utils_System::civiExit();
 107     }
 108   }
 109
 110   function set($key, &$value) {
 111     $key = $this->cleanKey($key);
 112     if (!$this->_cache->set($key, $value, $this->_timeout)) {
 113       CRM_Core_Error::debug( 'Result Code: ', $this->_cache->getResultMessage());
 114       CRM_Core_Error::fatal("memcached set failed, wondering why?, $key", $value );
 115       return FALSE;
 116     }
 117     return TRUE;
 118   }
 119
 120   function &get($key) {
 121     $key = $this->cleanKey($key);
 122     $result = $this->_cache->get($key);
 123     return $result;
 124   }
 125
 126   function delete($key) {
 127     $key = $this->cleanKey($key);
 128     return $this->_cache->delete($key);
 129   }
 130
 131   function cleanKey($key) {
 132     $key = preg_replace('/\s+|\W+/', '_', $this->_prefix . $key);
 133     if ( strlen($key) > self::MAX_KEY_LEN ) {
 134       $md5Key = md5($key);  // this should be 32 characters in length
 135       $subKeyLen = self::MAX_KEY_LEN - 1 - strlen($md5Key);
 136       $key = substr($key, 0, $subKeyLen) . "_" . $md5Key;
 137     }
 138     return $key;
 139   }
 140
 141   function flush() {
 142     return $this->_cache->flush();
 143   }
 144 }