CRM/Utils/Cache/Interface.php

   1 <?php
   2 /*
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   4  | CiviCRM version 5                                                  |
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   6  | Copyright CiviCRM LLC (c) 2004-2018                                |
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  26  */
  27
  28 /**
  29  *
  30  * @package CRM
  31  * @copyright CiviCRM LLC (c) 2004-2018
  32  *
  33  * CRM_Utils_Cache_Interface
  34  *
  35  * PHP-FIG has been developing a draft standard for caching,
  36  * PSR-6. The standard has not been ratified yet. When
  37  * making changes to this interface, please take care to
  38  * avoid *conflicst* with PSR-6's CacheItemPoolInterface. At
  39  * time of writing, they do not conflict. Avoiding conflicts
  40  * will enable more transition paths where Civi
  41  * simultaneously supports both interfaces in the same
  42  * implementation.
  43  *
  44  * For example, the current interface defines:
  45  *
  46  *   function get($key) => mixed $value
  47  *
  48  * and PSR-6 defines:
  49  *
  50  *   function getItem($key) => ItemInterface $item
  51  *
  52  * These are different styles (e.g. "weak item" vs "strong item"),
  53  * but the two methods do not *conflict*. They can coexist,
  54  * and you can trivially write adapters between the two.
  55  *
  56  * @see https://github.com/php-fig/fig-standards/blob/master/proposed/cache.md
  57  */
  58 interface CRM_Utils_Cache_Interface {
  59
  60   /**
  61    * Set the value in the cache.
  62    *
  63    * @param string $key
  64    * @param mixed $value
  65    */
  66   public function set($key, &$value);
  67
  68   /**
  69    * Get a value from the cache.
  70    *
  71    * @param string $key
  72    * @return mixed
  73    *   NULL if $key has not been previously set
  74    */
  75   public function get($key);
  76
  77   /**
  78    * Delete a value from the cache.
  79    *
  80    * @param string $key
  81    */
  82   public function delete($key);
  83
  84   /**
  85    * Delete all values from the cache.
  86    */
  87   public function flush();
  88
  89 }