CRM/Utils/Cache.php

   1 <?php
   2 /*
   3  +--------------------------------------------------------------------+
   4  | CiviCRM version 4.6                                                |
   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
  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    * @static
  47    */
  48   static private $_singleton = NULL;
  49
  50   /**
  51    * Constructor
  52    *
  53    * @param array $config an array of configuration params
  54    *
  55    * @return \CRM_Utils_Cache
  56    */
  57   public function __construct(&$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    * @static
  66    *
  67    */
  68   public static function &singleton() {
  69     if (self::$_singleton === NULL) {
  70       $className = 'ArrayCache';   // default to ArrayCache for now
  71
  72       // Maintain backward compatibility for now.
  73       // Setting CIVICRM_USE_MEMCACHE or CIVICRM_USE_ARRAYCACHE will
  74       // override the CIVICRM_DB_CACHE_CLASS setting.
  75       // Going forward, CIVICRM_USE_xxxCACHE should be deprecated.
  76       if (defined('CIVICRM_USE_MEMCACHE') && CIVICRM_USE_MEMCACHE) {
  77         $className = 'Memcache';
  78       }
  79       else if (defined('CIVICRM_USE_ARRAYCACHE') && CIVICRM_USE_ARRAYCACHE) {
  80         $className = 'ArrayCache';
  81       }
  82       else if (defined('CIVICRM_DB_CACHE_CLASS') && CIVICRM_DB_CACHE_CLASS) {
  83         $className = CIVICRM_DB_CACHE_CLASS;
  84       }
  85
  86       // a generic method for utilizing any of the available db caches.
  87       $dbCacheClass = 'CRM_Utils_Cache_' . $className;
  88       require_once(str_replace('_', DIRECTORY_SEPARATOR, $dbCacheClass) . '.php');
  89       $settings = self::getCacheSettings($className);
  90       self::$_singleton = new $dbCacheClass($settings);
  91     }
  92     return self::$_singleton;
  93   }
  94
  95   /**
  96    * Get cache relevant settings
  97    *
  98    * @param $cachePlugin
  99    *
 100    * @return array
 101    *   associative array of settings for the cache
 102    * @static
 103    */
 104   public static function getCacheSettings($cachePlugin) {
 105     switch ($cachePlugin) {
 106       case 'ArrayCache':
 107       case 'NoCache':
 108         $defaults = array();
 109         break;
 110
 111       case 'Memcache':
 112       case 'Memcached':
 113         $defaults = array(
 114           'host' => 'localhost',
 115           'port' => 11211,
 116           'timeout' => 3600,
 117           'prefix' => '',
 118         );
 119
 120         // Use old constants if needed to ensure backward compatability
 121         if (defined('CIVICRM_MEMCACHE_HOST')) {
 122           $defaults['host'] = CIVICRM_MEMCACHE_HOST;
 123         }
 124
 125         if (defined('CIVICRM_MEMCACHE_PORT')) {
 126           $defaults['port'] = CIVICRM_MEMCACHE_PORT;
 127         }
 128
 129         if (defined('CIVICRM_MEMCACHE_TIMEOUT')) {
 130           $defaults['timeout'] = CIVICRM_MEMCACHE_TIMEOUT;
 131         }
 132
 133         if (defined('CIVICRM_MEMCACHE_PREFIX')) {
 134           $defaults['prefix'] = CIVICRM_MEMCACHE_PREFIX;
 135         }
 136
 137         // Use new constants if possible
 138         if (defined('CIVICRM_DB_CACHE_HOST')) {
 139           $defaults['host'] = CIVICRM_DB_CACHE_HOST;
 140         }
 141
 142         if (defined('CIVICRM_DB_CACHE_PORT')) {
 143           $defaults['port'] = CIVICRM_DB_CACHE_PORT;
 144         }
 145
 146         if (defined('CIVICRM_DB_CACHE_TIMEOUT')) {
 147           $defaults['timeout'] = CIVICRM_DB_CACHE_TIMEOUT;
 148         }
 149
 150         if (defined('CIVICRM_DB_CACHE_PREFIX')) {
 151           $defaults['prefix'] = CIVICRM_DB_CACHE_PREFIX;
 152         }
 153
 154         break;
 155
 156       case 'APCcache':
 157         $defaults = array();
 158         if (defined('CIVICRM_DB_CACHE_TIMEOUT')) {
 159           $defaults['timeout'] = CIVICRM_DB_CACHE_TIMEOUT;
 160         }
 161         if (defined('CIVICRM_DB_CACHE_PREFIX')) {
 162           $defaults['prefix'] = CIVICRM_DB_CACHE_PREFIX;
 163         }
 164         break;
 165     }
 166     return $defaults;
 167   }
 168 }