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  */
  33
  34 /**
  35  * Cache is an empty base object, we'll modify the scheme when we have different caching schemes
  36  */
  37 class CRM_Utils_Cache {
  38   /**
  39    * We only need one instance of this object. So we use the singleton
  40    * pattern and cache the instance in this variable
  41    *
  42    * @var object
  43    */
  44   static private $_singleton = NULL;
  45
  46   /**
  47    * Constructor.
  48    *
  49    * @param array $config
  50    *   An array of configuration params.
  51    *
  52    * @return \CRM_Utils_Cache
  53    */
  54   public function __construct(&$config) {
  55     CRM_Core_Error::fatal(ts('this is just an interface and should not be called directly'));
  56   }
  57
  58   /**
  59    * Singleton function used to manage this object.
  60    *
  61    * @return CRM_Utils_Cache_Interface
  62    */
  63   public static function &singleton() {
  64     if (self::$_singleton === NULL) {
  65       $className = 'ArrayCache';   // default to ArrayCache for now
  66
  67       // Maintain backward compatibility for now.
  68       // Setting CIVICRM_USE_MEMCACHE or CIVICRM_USE_ARRAYCACHE will
  69       // override the CIVICRM_DB_CACHE_CLASS setting.
  70       // Going forward, CIVICRM_USE_xxxCACHE should be deprecated.
  71       if (defined('CIVICRM_USE_MEMCACHE') && CIVICRM_USE_MEMCACHE) {
  72         $className = 'Memcache';
  73       }
  74       elseif (defined('CIVICRM_USE_ARRAYCACHE') && CIVICRM_USE_ARRAYCACHE) {
  75         $className = 'ArrayCache';
  76       }
  77       elseif (defined('CIVICRM_DB_CACHE_CLASS') && CIVICRM_DB_CACHE_CLASS) {
  78         $className = CIVICRM_DB_CACHE_CLASS;
  79       }
  80
  81       // a generic method for utilizing any of the available db caches.
  82       $dbCacheClass = 'CRM_Utils_Cache_' . $className;
  83       $settings = self::getCacheSettings($className);
  84       self::$_singleton = new $dbCacheClass($settings);
  85     }
  86     return self::$_singleton;
  87   }
  88
  89   /**
  90    * Get cache relevant settings.
  91    *
  92    * @param $cachePlugin
  93    *
  94    * @return array
  95    *   associative array of settings for the cache
  96    */
  97   public static function getCacheSettings($cachePlugin) {
  98     switch ($cachePlugin) {
  99       case 'ArrayCache':
 100       case 'NoCache':
 101         $defaults = array();
 102         break;
 103
 104       case 'Redis':
 105       case 'Memcache':
 106       case 'Memcached':
 107         $defaults = array(
 108           'host' => 'localhost',
 109           'port' => 11211,
 110           'timeout' => 3600,
 111           'prefix' => '',
 112         );
 113
 114         // Use old constants if needed to ensure backward compatibility
 115         if (defined('CIVICRM_MEMCACHE_HOST')) {
 116           $defaults['host'] = CIVICRM_MEMCACHE_HOST;
 117         }
 118
 119         if (defined('CIVICRM_MEMCACHE_PORT')) {
 120           $defaults['port'] = CIVICRM_MEMCACHE_PORT;
 121         }
 122
 123         if (defined('CIVICRM_MEMCACHE_TIMEOUT')) {
 124           $defaults['timeout'] = CIVICRM_MEMCACHE_TIMEOUT;
 125         }
 126
 127         if (defined('CIVICRM_MEMCACHE_PREFIX')) {
 128           $defaults['prefix'] = CIVICRM_MEMCACHE_PREFIX;
 129         }
 130
 131         // Use new constants if possible
 132         if (defined('CIVICRM_DB_CACHE_HOST')) {
 133           $defaults['host'] = CIVICRM_DB_CACHE_HOST;
 134         }
 135
 136         if (defined('CIVICRM_DB_CACHE_PORT')) {
 137           $defaults['port'] = CIVICRM_DB_CACHE_PORT;
 138         }
 139
 140         if (defined('CIVICRM_DB_CACHE_TIMEOUT')) {
 141           $defaults['timeout'] = CIVICRM_DB_CACHE_TIMEOUT;
 142         }
 143
 144         if (defined('CIVICRM_DB_CACHE_PREFIX')) {
 145           $defaults['prefix'] = CIVICRM_DB_CACHE_PREFIX;
 146         }
 147
 148         break;
 149
 150       case 'APCcache':
 151         $defaults = array();
 152         if (defined('CIVICRM_DB_CACHE_TIMEOUT')) {
 153           $defaults['timeout'] = CIVICRM_DB_CACHE_TIMEOUT;
 154         }
 155         if (defined('CIVICRM_DB_CACHE_PREFIX')) {
 156           $defaults['prefix'] = CIVICRM_DB_CACHE_PREFIX;
 157         }
 158         break;
 159     }
 160     return $defaults;
 161   }
 162
 163   /**
 164    * Create a new, named, limited-use cache.
 165    *
 166    * This is a factory function. Generally, you should use Civi::cache($name)
 167    * to locate managed cached instance.
 168    *
 169    * @param array $params
 170    *   Array with keys:
 171    *   - name: string, unique symbolic name.
 172    *   - type: array|string, list of acceptable cache types, in order of preference.
 173    *   - prefetch: bool, whether to prefetch all data in cache (if possible).
 174    * @return CRM_Utils_Cache_Interface
 175    * @throws CRM_Core_Exception
 176    * @see Civi::cache()
 177    */
 178   public static function create($params = array()) {
 179     $types = (array) $params['type'];
 180
 181     foreach ($types as $type) {
 182       switch ($type) {
 183         case '*memory*':
 184           if (defined('CIVICRM_DB_CACHE_CLASS') && in_array(CIVICRM_DB_CACHE_CLASS, array('Memcache', 'Memcached', 'Redis'))) {
 185             $dbCacheClass = 'CRM_Utils_Cache_' . CIVICRM_DB_CACHE_CLASS;
 186             $settings = self::getCacheSettings(CIVICRM_DB_CACHE_CLASS);
 187             $settings['prefix'] = $settings['prefix'] . '_' . $params['name'];
 188             return new $dbCacheClass($settings);
 189           }
 190           break;
 191
 192         case 'SqlGroup':
 193           if (defined('CIVICRM_DSN') && CIVICRM_DSN) {
 194             return new CRM_Utils_Cache_SqlGroup(array(
 195               'group' => $params['name'],
 196               'prefetch' => CRM_Utils_Array::value('prefetch', $params, FALSE),
 197             ));
 198           }
 199           break;
 200
 201         case 'Arraycache':
 202         case 'ArrayCache':
 203           return new CRM_Utils_Cache_ArrayCache(array());
 204
 205       }
 206     }
 207
 208     throw new CRM_Core_Exception("Failed to instantiate cache. No supported cache type found. " . print_r($params, 1));
 209   }
 210
 211 }