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
  35   use CRM_Utils_Cache_NaiveMultipleTrait; // TODO Consider native implementation.
  36
  37   const DEFAULT_HOST = 'localhost';
  38   const DEFAULT_PORT = 11211;
  39   const DEFAULT_TIMEOUT = 3600;
  40   const DEFAULT_PREFIX = '';
  41   const MAX_KEY_LEN = 62;
  42
  43   /**
  44    * The host name of the memcached server
  45    *
  46    * @var string
  47    */
  48   protected $_host = self::DEFAULT_HOST;
  49
  50   /**
  51    * The port on which to connect on
  52    *
  53    * @var int
  54    */
  55   protected $_port = self::DEFAULT_PORT;
  56
  57   /**
  58    * The default timeout to use
  59    *
  60    * @var int
  61    */
  62   protected $_timeout = self::DEFAULT_TIMEOUT;
  63
  64   /**
  65    * The prefix prepended to cache keys.
  66    *
  67    * If we are using the same memcache instance for multiple CiviCRM
  68    * installs, we must have a unique prefix for each install to prevent
  69    * the keys from clobbering each other.
  70    *
  71    * @var string
  72    */
  73   protected $_prefix = self::DEFAULT_PREFIX;
  74
  75   /**
  76    * The actual memcache object.
  77    *
  78    * @var Memcached
  79    */
  80   protected $_cache;
  81
  82   /**
  83    * Constructor.
  84    *
  85    * @param array $config
  86    *   An array of configuration params.
  87    *
  88    * @return \CRM_Utils_Cache_Memcached
  89    */
  90   public function __construct($config) {
  91     if (isset($config['host'])) {
  92       $this->_host = $config['host'];
  93     }
  94     if (isset($config['port'])) {
  95       $this->_port = $config['port'];
  96     }
  97     if (isset($config['timeout'])) {
  98       $this->_timeout = $config['timeout'];
  99     }
 100     if (isset($config['prefix'])) {
 101       $this->_prefix = $config['prefix'];
 102     }
 103
 104     $this->_cache = new Memcached();
 105
 106     if (!$this->_cache->addServer($this->_host, $this->_port)) {
 107       // dont use fatal here since we can go in an infinite loop
 108       echo 'Could not connect to Memcached server';
 109       CRM_Utils_System::civiExit();
 110     }
 111   }
 112
 113   /**
 114    * @param $key
 115    * @param $value
 116    * @param null|int|\DateInterval $ttl
 117    *
 118    * @return bool
 119    * @throws Exception
 120    */
 121   public function set($key, $value, $ttl = NULL) {
 122     if ($ttl !== NULL) {
 123       throw new \RuntimeException("FIXME: " . __CLASS__ . "::set() should support non-NULL TTL");
 124     }
 125     $key = $this->cleanKey($key);
 126     if (!$this->_cache->set($key, $value, $this->_timeout)) {
 127       CRM_Core_Error::debug('Result Code: ', $this->_cache->getResultMessage());
 128       CRM_Core_Error::fatal("memcached set failed, wondering why?, $key", $value);
 129       return FALSE;
 130     }
 131     return TRUE;
 132   }
 133
 134   /**
 135    * @param $key
 136    * @param mixed $default
 137    *
 138    * @return mixed
 139    */
 140   public function get($key, $default = NULL) {
 141     if ($default !== NULL) {
 142       throw new \RuntimeException("FIXME: " . __CLASS__ . "::get() only supports NULL default");
 143     }
 144     $key = $this->cleanKey($key);
 145     $result = $this->_cache->get($key);
 146     return $result;
 147   }
 148
 149   /**
 150    * @param $key
 151    *
 152    * @return mixed
 153    */
 154   public function delete($key) {
 155     $key = $this->cleanKey($key);
 156     return $this->_cache->delete($key);
 157   }
 158
 159   /**
 160    * @param $key
 161    *
 162    * @return mixed|string
 163    */
 164   public function cleanKey($key) {
 165     $key = preg_replace('/\s+|\W+/', '_', $this->_prefix . $key);
 166     if (strlen($key) > self::MAX_KEY_LEN) {
 167       $md5Key = md5($key);  // this should be 32 characters in length
 168       $subKeyLen = self::MAX_KEY_LEN - 1 - strlen($md5Key);
 169       $key = substr($key, 0, $subKeyLen) . "_" . $md5Key;
 170     }
 171     return $key;
 172   }
 173
 174   /**
 175    * @return mixed
 176    */
 177   public function flush() {
 178     // FIXME: Only delete items matching `$this->_prefix`.
 179     return $this->_cache->flush();
 180   }
 181
 182 }