CRM/Utils/Cache.php

   1 <?php
   2 /*
   3  +--------------------------------------------------------------------+
   4  | CiviCRM version 4.7                                                |
   5  +--------------------------------------------------------------------+
   6  | Copyright CiviCRM LLC (c) 2004-2015                                |
   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) 2004-2015
  32  * $Id$
  33  *
  34  */
  35
  36 /**
  37  * Cache is an empty base object, we'll modify the scheme when we have different caching schemes
  38  *
  39  */
  40 class CRM_Utils_Cache {
  41   /**
  42    * We only need one instance of this object. So we use the singleton
  43    * pattern and cache the instance in this variable
  44    *
  45    * @var object
  46    */
  47   static private $_singleton = NULL;
  48
  49   /**
  50    * Constructor.
  51    *
  52    * @param array $config
  53    *   An array of configuration params.
  54    *
  55    * @return \CRM_Utils_Cache
  56    */
  57   public function __construct(&$config) {
  58     CRM_Core_Error::fatal(ts('this is just an interface and should not be called directly'));
  59   }
  60
  61   /**
  62    * Singleton function used to manage this object.
  63    *
  64    * @return object
  65    */
  66   public static function &singleton() {
  67     if (self::$_singleton === NULL) {
  68       $className = 'ArrayCache';   // default to ArrayCache for now
  69
  70       // Maintain backward compatibility for now.
  71       // Setting CIVICRM_USE_MEMCACHE or CIVICRM_USE_ARRAYCACHE will
  72       // override the CIVICRM_DB_CACHE_CLASS setting.
  73       // Going forward, CIVICRM_USE_xxxCACHE should be deprecated.
  74       if (defined('CIVICRM_USE_MEMCACHE') && CIVICRM_USE_MEMCACHE) {
  75         $className = 'Memcache';
  76       }
  77       elseif (defined('CIVICRM_USE_ARRAYCACHE') && CIVICRM_USE_ARRAYCACHE) {
  78         $className = 'ArrayCache';
  79       }
  80       elseif (defined('CIVICRM_DB_CACHE_CLASS') && CIVICRM_DB_CACHE_CLASS) {
  81         $className = CIVICRM_DB_CACHE_CLASS;
  82       }
  83
  84       // a generic method for utilizing any of the available db caches.
  85       $dbCacheClass = 'CRM_Utils_Cache_' . $className;
  86       $settings = self::getCacheSettings($className);
  87       self::$_singleton = new $dbCacheClass($settings);
  88     }
  89     return self::$_singleton;
  90   }
  91
  92   /**
  93    * Get cache relevant settings.
  94    *
  95    * @param $cachePlugin
  96    *
  97    * @return array
  98    *   associative array of settings for the cache
  99    */
 100   public static function getCacheSettings($cachePlugin) {
 101     switch ($cachePlugin) {
 102       case 'ArrayCache':
 103       case 'NoCache':
 104         $defaults = array();
 105         break;
 106
 107       case 'Memcache':
 108       case 'Memcached':
 109         $defaults = array(
 110           'host' => 'localhost',
 111           'port' => 11211,
 112           'timeout' => 3600,
 113           'prefix' => '',
 114         );
 115
 116         // Use old constants if needed to ensure backward compatibility
 117         if (defined('CIVICRM_MEMCACHE_HOST')) {
 118           $defaults['host'] = CIVICRM_MEMCACHE_HOST;
 119         }
 120
 121         if (defined('CIVICRM_MEMCACHE_PORT')) {
 122           $defaults['port'] = CIVICRM_MEMCACHE_PORT;
 123         }
 124
 125         if (defined('CIVICRM_MEMCACHE_TIMEOUT')) {
 126           $defaults['timeout'] = CIVICRM_MEMCACHE_TIMEOUT;
 127         }
 128
 129         if (defined('CIVICRM_MEMCACHE_PREFIX')) {
 130           $defaults['prefix'] = CIVICRM_MEMCACHE_PREFIX;
 131         }
 132
 133         // Use new constants if possible
 134         if (defined('CIVICRM_DB_CACHE_HOST')) {
 135           $defaults['host'] = CIVICRM_DB_CACHE_HOST;
 136         }
 137
 138         if (defined('CIVICRM_DB_CACHE_PORT')) {
 139           $defaults['port'] = CIVICRM_DB_CACHE_PORT;
 140         }
 141
 142         if (defined('CIVICRM_DB_CACHE_TIMEOUT')) {
 143           $defaults['timeout'] = CIVICRM_DB_CACHE_TIMEOUT;
 144         }
 145
 146         if (defined('CIVICRM_DB_CACHE_PREFIX')) {
 147           $defaults['prefix'] = CIVICRM_DB_CACHE_PREFIX;
 148         }
 149
 150         break;
 151
 152       case 'APCcache':
 153         $defaults = array();
 154         if (defined('CIVICRM_DB_CACHE_TIMEOUT')) {
 155           $defaults['timeout'] = CIVICRM_DB_CACHE_TIMEOUT;
 156         }
 157         if (defined('CIVICRM_DB_CACHE_PREFIX')) {
 158           $defaults['prefix'] = CIVICRM_DB_CACHE_PREFIX;
 159         }
 160         break;
 161     }
 162     return $defaults;
 163   }
 164
 165 }