CRM/Utils/Cache/FastArrayDecorator.php

   1 <?php
   2 /*
   3  +--------------------------------------------------------------------+
   4  | CiviCRM version 5                                                  |
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   6  | Copyright CiviCRM LLC (c) 2004-2019                                |
   7  +--------------------------------------------------------------------+
   8  | This file is a part of CiviCRM.                                    |
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  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         |
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  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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  22  | at info[AT]civicrm[DOT]org. If you have questions about the        |
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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_FastArrayDecorator
  36  *
  37  * Like CRM_Utils_Cache_ArrayDecorator, this creates a two-tier cache.
  38  * But it's... faster. The speed improvements are achieved by sacrificing
  39  * compliance with PSR-16. Specific trade-offs:
  40  *
  41  * 1. TTL values are not tracked locally. Any data cached locally will stay
  42  *    active until the instance is destroyed (i.e. until the request ends).
  43  *    You won't notice this is you have short-lived requests and long-lived caches.
  44  * 2. If you store an *object* in the local cache, the same object instance
  45  *    will be used through the end of the request. If you modify a property
  46  *    of the object, the change will endure within the current pageview but
  47  *    will not pass-through to the persistent cache.
  48  *
  49  * But... it is twice as fast (on high-volume reads).
  50  *
  51  * Ex: $cache = new CRM_Utils_Cache_FastArrayDecorator(new CRM_Utils_Cache_Redis(...));
  52  *
  53  * @see CRM_Utils_Cache_ArrayDecorator
  54  */
  55 class CRM_Utils_Cache_FastArrayDecorator implements CRM_Utils_Cache_Interface {
  56
  57   use CRM_Utils_Cache_NaiveMultipleTrait; // TODO Consider native implementation.
  58
  59   /**
  60    * @var int
  61    *   Default time-to-live (seconds) for cache items that don't have a TTL.
  62    */
  63   protected $defaultTimeout;
  64
  65   /**
  66    * @var CRM_Utils_Cache_Interface
  67    */
  68   private $delegate;
  69
  70   /**
  71    * @var array
  72    *   Array(string $cacheKey => mixed $cacheValue).
  73    */
  74   private $values = [];
  75
  76   /**
  77    * CRM_Utils_Cache_FastArrayDecorator constructor.
  78    * @param \CRM_Utils_Cache_Interface $delegate
  79    * @param int $defaultTimeout
  80    *   Default number of seconds each cache-item should endure.
  81    */
  82   public function __construct(\CRM_Utils_Cache_Interface $delegate, $defaultTimeout = 3600) {
  83     $this->defaultTimeout = $defaultTimeout;
  84     $this->delegate = $delegate;
  85   }
  86
  87   public function set($key, $value, $ttl = NULL) {
  88     if (is_int($ttl) && $ttl <= 0) {
  89       return $this->delete($key);
  90     }
  91
  92     if ($this->delegate->set($key, $value, $ttl)) {
  93       $this->values[$key] = $value;
  94       return TRUE;
  95     }
  96     else {
  97       return FALSE;
  98     }
  99   }
 100
 101   public function get($key, $default = NULL) {
 102     if (array_key_exists($key, $this->values)) {
 103       return $this->values[$key];
 104     }
 105
 106     $nack = CRM_Utils_Cache::nack();
 107     $value = $this->delegate->get($key, $nack);
 108     if ($value === $nack) {
 109       return $default;
 110     }
 111
 112     $this->values[$key] = $value;
 113     return $value;
 114   }
 115
 116   public function delete($key) {
 117     unset($this->values[$key]);
 118     return $this->delegate->delete($key);
 119   }
 120
 121   public function flush() {
 122     return $this->clear();
 123   }
 124
 125   public function clear() {
 126     $this->values = [];
 127     return $this->delegate->clear();
 128   }
 129
 130   public function has($key) {
 131     return $this->delegate->has($key);
 132   }
 133
 134 }