CRM/Utils/Cache/ArrayDecorator.php

   1 <?php
   2 /*
   3  +--------------------------------------------------------------------+
   4  | CiviCRM version 5                                                  |
   5  +--------------------------------------------------------------------+
   6  | Copyright CiviCRM LLC (c) 2004-2019                                |
   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.        |
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  19  | You should have received a copy of the GNU Affero General Public   |
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  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        |
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  26  */
  27
  28 /**
  29  *
  30  * @package CRM
  31  * @copyright CiviCRM LLC (c) 2004-2019
  32  */
  33
  34 /**
  35  * Class CRM_Utils_Cache_ArrayDecorator
  36  *
  37  * This creates a two-tier cache-hierarchy: a thread-local, array-based cache
  38  * combined with some third-party cache driver.
  39  *
  40  * Ex: $cache = new CRM_Utils_Cache_ArrayDecorator(new CRM_Utils_Cache_Redis(...));
  41  */
  42 class CRM_Utils_Cache_ArrayDecorator implements CRM_Utils_Cache_Interface {
  43
  44   use CRM_Utils_Cache_NaiveMultipleTrait; // TODO Consider native implementation.
  45
  46   /**
  47    * @var int
  48    *   Default time-to-live (seconds) for cache items that don't have a TTL.
  49    */
  50   protected $defaultTimeout;
  51
  52   /**
  53    * @var CRM_Utils_Cache_Interface
  54    */
  55   private $delegate;
  56
  57   /**
  58    * @var array
  59    *   Array(string $cacheKey => mixed $cacheValue).
  60    */
  61   private $values = [];
  62
  63   /**
  64    * @var array
  65    *   Array(string $cacheKey => int $expirationTime).
  66    */
  67   private $expires = [];
  68
  69   /**
  70    * CRM_Utils_Cache_ArrayDecorator constructor.
  71    * @param \CRM_Utils_Cache_Interface $delegate
  72    * @param int $defaultTimeout
  73    *   Default number of seconds each cache-item should endure.
  74    */
  75   public function __construct(\CRM_Utils_Cache_Interface $delegate, $defaultTimeout = 3600) {
  76     $this->defaultTimeout = $defaultTimeout;
  77     $this->delegate = $delegate;
  78   }
  79
  80   public function set($key, $value, $ttl = NULL) {
  81     if (is_int($ttl) && $ttl <= 0) {
  82       return $this->delete($key);
  83     }
  84
  85     $expiresAt = CRM_Utils_Date::convertCacheTtlToExpires($ttl, $this->defaultTimeout);
  86     if ($this->delegate->set($key, [$expiresAt, $value], $ttl)) {
  87       $this->values[$key] = $this->reobjectify($value);
  88       $this->expires[$key] = $expiresAt;
  89       return TRUE;
  90     }
  91     else {
  92       return FALSE;
  93     }
  94   }
  95
  96   public function get($key, $default = NULL) {
  97     CRM_Utils_Cache::assertValidKey($key);
  98     if (array_key_exists($key, $this->values) && $this->expires[$key] > CRM_Utils_Time::getTimeRaw()) {
  99       return $this->reobjectify($this->values[$key]);
 100     }
 101
 102     $nack = CRM_Utils_Cache::nack();
 103     $value = $this->delegate->get($key, $nack);
 104     if ($value === $nack) {
 105       return $default;
 106     }
 107
 108     $this->expires[$key] = $value[0];
 109     $this->values[$key] = $value[1];
 110     return $this->reobjectify($this->values[$key]);
 111   }
 112
 113   public function delete($key) {
 114     CRM_Utils_Cache::assertValidKey($key);
 115     unset($this->values[$key]);
 116     unset($this->expires[$key]);
 117     return $this->delegate->delete($key);
 118   }
 119
 120   public function flush() {
 121     return $this->clear();
 122   }
 123
 124   public function clear() {
 125     $this->values = [];
 126     $this->expires = [];
 127     return $this->delegate->clear();
 128   }
 129
 130   public function has($key) {
 131     CRM_Utils_Cache::assertValidKey($key);
 132     if (array_key_exists($key, $this->values) && $this->expires[$key] > CRM_Utils_Time::getTimeRaw()) {
 133       return TRUE;
 134     }
 135     return $this->delegate->has($key);
 136   }
 137
 138   private function reobjectify($value) {
 139     return is_object($value) ? unserialize(serialize($value)) : $value;
 140   }
 141
 142 }