library/HTMLPurifier/DefinitionCacheFactory.php

   1 <?php
   2
   3 /**
   4  * Responsible for creating definition caches.
   5  */
   6 class HTMLPurifier_DefinitionCacheFactory
   7 {
   8     /**
   9      * @type array
  10      */
  11     protected $caches = array('Serializer' => array());
  12
  13     /**
  14      * @type array
  15      */
  16     protected $implementations = array();
  17
  18     /**
  19      * @type HTMLPurifier_DefinitionCache_Decorator[]
  20      */
  21     protected $decorators = array();
  22
  23     /**
  24      * Initialize default decorators
  25      */
  26     public function setup()
  27     {
  28         $this->addDecorator('Cleanup');
  29     }
  30
  31     /**
  32      * Retrieves an instance of global definition cache factory.
  33      * @param HTMLPurifier_DefinitionCacheFactory $prototype
  34      * @return HTMLPurifier_DefinitionCacheFactory
  35      */
  36     public static function instance($prototype = null)
  37     {
  38         static $instance;
  39         if ($prototype !== null) {
  40             $instance = $prototype;
  41         } elseif ($instance === null || $prototype === true) {
  42             $instance = new HTMLPurifier_DefinitionCacheFactory();
  43             $instance->setup();
  44         }
  45         return $instance;
  46     }
  47
  48     /**
  49      * Registers a new definition cache object
  50      * @param string $short Short name of cache object, for reference
  51      * @param string $long Full class name of cache object, for construction
  52      */
  53     public function register($short, $long)
  54     {
  55         $this->implementations[$short] = $long;
  56     }
  57
  58     /**
  59      * Factory method that creates a cache object based on configuration
  60      * @param string $type Name of definitions handled by cache
  61      * @param HTMLPurifier_Config $config Config instance
  62      * @return mixed
  63      */
  64     public function create($type, $config)
  65     {
  66         $method = $config->get('Cache.DefinitionImpl');
  67         if ($method === null) {
  68             return new HTMLPurifier_DefinitionCache_Null($type);
  69         }
  70         if (!empty($this->caches[$method][$type])) {
  71             return $this->caches[$method][$type];
  72         }
  73         if (isset($this->implementations[$method]) &&
  74             class_exists($class = $this->implementations[$method], false)) {
  75             $cache = new $class($type);
  76         } else {
  77             if ($method != 'Serializer') {
  78                 trigger_error("Unrecognized DefinitionCache $method, using Serializer instead", E_USER_WARNING);
  79             }
  80             $cache = new HTMLPurifier_DefinitionCache_Serializer($type);
  81         }
  82         foreach ($this->decorators as $decorator) {
  83             $new_cache = $decorator->decorate($cache);
  84             // prevent infinite recursion in PHP 4
  85             unset($cache);
  86             $cache = $new_cache;
  87         }
  88         $this->caches[$method][$type] = $cache;
  89         return $this->caches[$method][$type];
  90     }
  91
  92     /**
  93      * Registers a decorator to add to all new cache objects
  94      * @param HTMLPurifier_DefinitionCache_Decorator|string $decorator An instance or the name of a decorator
  95      */
  96     public function addDecorator($decorator)
  97     {
  98         if (is_string($decorator)) {
  99             $class = "HTMLPurifier_DefinitionCache_Decorator_$decorator";
 100             $decorator = new $class;
 101         }
 102         $this->decorators[$decorator->name] = $decorator;
 103     }
 104 }
 105
 106 // vim: et sw=4 sts=4