CRM/Utils/Cache.php

   1 <?php
   2 /*
   3  +--------------------------------------------------------------------+
   4  | CiviCRM version 4.7                                                |
   5  +--------------------------------------------------------------------+
   6  | Copyright CiviCRM LLC (c) 2004-2017                                |
   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) 2004-2017
  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    * (Quasi-Private) Treat this as private. It is marked public to facilitate testing.
  40    *
  41    * We only need one instance of this object. So we use the singleton
  42    * pattern and cache the instance in this variable
  43    *
  44    * @var object
  45    */
  46   public static $_singleton = NULL;
  47
  48   /**
  49    * Constructor.
  50    *
  51    * @param array $config
  52    *   An array of configuration params.
  53    *
  54    * @return \CRM_Utils_Cache
  55    */
  56   public function __construct(&$config) {
  57     CRM_Core_Error::fatal(ts('this is just an interface and should not be called directly'));
  58   }
  59
  60   /**
  61    * Singleton function used to manage this object.
  62    *
  63    * @return CRM_Utils_Cache_Interface
  64    */
  65   public static function &singleton() {
  66     if (self::$_singleton === NULL) {
  67       $className = 'ArrayCache';   // default to ArrayCache for now
  68
  69       // Maintain backward compatibility for now.
  70       // Setting CIVICRM_USE_MEMCACHE or CIVICRM_USE_ARRAYCACHE will
  71       // override the CIVICRM_DB_CACHE_CLASS setting.
  72       // Going forward, CIVICRM_USE_xxxCACHE should be deprecated.
  73       if (defined('CIVICRM_USE_MEMCACHE') && CIVICRM_USE_MEMCACHE) {
  74         $className = 'Memcache';
  75       }
  76       elseif (defined('CIVICRM_USE_ARRAYCACHE') && CIVICRM_USE_ARRAYCACHE) {
  77         $className = 'ArrayCache';
  78       }
  79       elseif (defined('CIVICRM_DB_CACHE_CLASS') && CIVICRM_DB_CACHE_CLASS) {
  80         $className = CIVICRM_DB_CACHE_CLASS;
  81       }
  82
  83       // a generic method for utilizing any of the available db caches.
  84       $dbCacheClass = 'CRM_Utils_Cache_' . $className;
  85       $settings = self::getCacheSettings($className);
  86       self::$_singleton = new $dbCacheClass($settings);
  87     }
  88     return self::$_singleton;
  89   }
  90
  91   /**
  92    * Get cache relevant settings.
  93    *
  94    * @param $cachePlugin
  95    *
  96    * @return array
  97    *   associative array of settings for the cache
  98    */
  99   public static function getCacheSettings($cachePlugin) {
 100     switch ($cachePlugin) {
 101       case 'ArrayCache':
 102       case 'NoCache':
 103         $defaults = array();
 104         break;
 105
 106       case 'Redis':
 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 $defaults;
 163   }
 164
 165   /**
 166    * Create a new, named, limited-use cache.
 167    *
 168    * This is a factory function. Generally, you should use Civi::cache($name)
 169    * to locate managed cached instance.
 170    *
 171    * @param array $params
 172    *   Array with keys:
 173    *   - name: string, unique symbolic name.
 174    *   - type: array|string, list of acceptable cache types, in order of preference.
 175    *   - prefetch: bool, whether to prefetch all data in cache (if possible).
 176    * @return CRM_Utils_Cache_Interface
 177    * @throws CRM_Core_Exception
 178    * @see Civi::cache()
 179    */
 180   public static function create($params = array()) {
 181     $types = (array) $params['type'];
 182
 183     foreach ($types as $type) {
 184       switch ($type) {
 185         case '*memory*':
 186           if (defined('CIVICRM_DB_CACHE_CLASS') && in_array(CIVICRM_DB_CACHE_CLASS, array('Memcache', 'Memcached', 'Redis'))) {
 187             $dbCacheClass = 'CRM_Utils_Cache_' . CIVICRM_DB_CACHE_CLASS;
 188             $settings = self::getCacheSettings(CIVICRM_DB_CACHE_CLASS);
 189             $settings['prefix'] = $settings['prefix'] . '_' . $params['name'];
 190             return new $dbCacheClass($settings);
 191           }
 192           break;
 193
 194         case 'SqlGroup':
 195           if (defined('CIVICRM_DSN') && CIVICRM_DSN) {
 196             return new CRM_Utils_Cache_SqlGroup(array(
 197               'group' => $params['name'],
 198               'prefetch' => CRM_Utils_Array::value('prefetch', $params, FALSE),
 199             ));
 200           }
 201           break;
 202
 203         case 'Arraycache':
 204         case 'ArrayCache':
 205           return new CRM_Utils_Cache_ArrayCache(array());
 206
 207       }
 208     }
 209
 210     throw new CRM_Core_Exception("Failed to instantiate cache. No supported cache type found. " . print_r($params, 1));
 211   }
 212
 213 }