CRM/Utils/Cache/Memcached.php

   1 <?php
   2 /*
   3  +--------------------------------------------------------------------+
   4  | CiviCRM version 5                                                  |
   5  +--------------------------------------------------------------------+
   6  | Copyright CiviCRM LLC (c) 2004-2018                                |
   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) 2004-2018
  32  */
  33 class CRM_Utils_Cache_Memcached implements CRM_Utils_Cache_Interface {
  34   const DEFAULT_HOST = 'localhost';
  35   const DEFAULT_PORT = 11211;
  36   const DEFAULT_TIMEOUT = 3600;
  37   const DEFAULT_PREFIX = '';
  38   const MAX_KEY_LEN = 62;
  39
  40   /**
  41    * The host name of the memcached server
  42    *
  43    * @var string
  44    */
  45   protected $_host = self::DEFAULT_HOST;
  46
  47   /**
  48    * The port on which to connect on
  49    *
  50    * @var int
  51    */
  52   protected $_port = self::DEFAULT_PORT;
  53
  54   /**
  55    * The default timeout to use
  56    *
  57    * @var int
  58    */
  59   protected $_timeout = self::DEFAULT_TIMEOUT;
  60
  61   /**
  62    * The prefix prepended to cache keys.
  63    *
  64    * If we are using the same memcache instance for multiple CiviCRM
  65    * installs, we must have a unique prefix for each install to prevent
  66    * the keys from clobbering each other.
  67    *
  68    * @var string
  69    */
  70   protected $_prefix = self::DEFAULT_PREFIX;
  71
  72   /**
  73    * The actual memcache object.
  74    *
  75    * @var Memcached
  76    */
  77   protected $_cache;
  78
  79   /**
  80    * Constructor.
  81    *
  82    * @param array $config
  83    *   An array of configuration params.
  84    *
  85    * @return \CRM_Utils_Cache_Memcached
  86    */
  87   public function __construct($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   /**
 111    * @param $key
 112    * @param $value
 113    * @param null|int|\DateInterval $ttl
 114    *
 115    * @return bool
 116    * @throws Exception
 117    */
 118   public function set($key, $value, $ttl = NULL) {
 119     if ($ttl !== NULL) {
 120       throw new \RuntimeException("FIXME: " . __CLASS__ . "::set() should support non-NULL TTL");
 121     }
 122     $key = $this->cleanKey($key);
 123     if (!$this->_cache->set($key, $value, $this->_timeout)) {
 124       CRM_Core_Error::debug('Result Code: ', $this->_cache->getResultMessage());
 125       CRM_Core_Error::fatal("memcached set failed, wondering why?, $key", $value);
 126       return FALSE;
 127     }
 128     return TRUE;
 129   }
 130
 131   /**
 132    * @param $key
 133    * @param mixed $default
 134    *
 135    * @return mixed
 136    */
 137   public function get($key, $default = NULL) {
 138     if ($default !== NULL) {
 139       throw new \RuntimeException("FIXME: " . __CLASS__ . "::get() only supports NULL default");
 140     }
 141     $key = $this->cleanKey($key);
 142     $result = $this->_cache->get($key);
 143     return $result;
 144   }
 145
 146   /**
 147    * @param $key
 148    *
 149    * @return mixed
 150    */
 151   public function delete($key) {
 152     $key = $this->cleanKey($key);
 153     return $this->_cache->delete($key);
 154   }
 155
 156   /**
 157    * @param $key
 158    *
 159    * @return mixed|string
 160    */
 161   public function cleanKey($key) {
 162     $key = preg_replace('/\s+|\W+/', '_', $this->_prefix . $key);
 163     if (strlen($key) > self::MAX_KEY_LEN) {
 164       $md5Key = md5($key);  // this should be 32 characters in length
 165       $subKeyLen = self::MAX_KEY_LEN - 1 - strlen($md5Key);
 166       $key = substr($key, 0, $subKeyLen) . "_" . $md5Key;
 167     }
 168     return $key;
 169   }
 170
 171   /**
 172    * @return mixed
 173    */
 174   public function flush() {
 175     // FIXME: Only delete items matching `$this->_prefix`.
 176     return $this->_cache->flush();
 177   }
 178
 179 }