Release 2.0.0, merged in 1026 to HEAD.

git-svn-id: http://htmlpurifier.org/svnroot/htmlpurifier/branches/strict@1179 48356398-32a2-884e-a903-53898d9a118a

library/HTMLPurifier/DefinitionCache.php

@@ -0,0 +1,121 @@
+<?php
+
+require_once 'HTMLPurifier/DefinitionCache/Serializer.php';
+require_once 'HTMLPurifier/DefinitionCache/Null.php';
+
+require_once 'HTMLPurifier/DefinitionCache/Decorator.php';
+
+/**
+ * Abstract class representing Definition cache managers that implements
+ * useful common methods and is a factory.
+ * @todo Get some sort of versioning variable so the library can easily
+ *       invalidate the cache with a new version
+ * @todo Make the test runner cache aware and allow the user to easily
+ *       flush the cache
+ * @todo Create a separate maintenance file advanced users can use to
+ *       cache their custom HTMLDefinition, which can be loaded
+ *       via a configuration directive
+ * @todo Implement memcached
+ */
+class HTMLPurifier_DefinitionCache
+{
+    
+    var $type;
+    
+    /**
+     * @param $name Type of definition objects this instance of the
+     *      cache will handle.
+     */
+    function HTMLPurifier_DefinitionCache($type) {
+        $this->type = $type;
+    }
+    
+    /**
+     * Generates a unique identifier for a particular configuration
+     * @param Instance of HTMLPurifier_Config
+     */
+    function generateKey($config) {
+        return $config->version . '-' . // possibly replace with function calls
+               $config->get($this->type, 'DefinitionRev') . '-' .
+               $config->getBatchSerial($this->type);
+    }
+    
+    /**
+     * Tests whether or not a key is old with respect to the configuration's
+     * version and revision number.
+     * @param $key Key to test
+     * @param $config Instance of HTMLPurifier_Config to test against
+     */
+    function isOld($key, $config) {
+        list($version, $revision, $hash) = explode('-', $key, 3);
+        $compare = version_compare($version, $config->version);
+        if ($compare > 0) return false;
+        if ($compare == 0 && $revision >= $config->get($this->type, 'DefinitionRev')) return false;
+        return true;
+    }
+    
+    /**
+     * Checks if a definition's type jives with the cache's type
+     * @note Throws an error on failure
+     * @param $def Definition object to check
+     * @return Boolean true if good, false if not
+     */
+    function checkDefType($def) {
+        if ($def->type !== $this->type) {
+            trigger_error("Cannot use definition of type {$def->type} in cache for {$this->type}");
+            return false;
+        }
+        return true;
+    }
+    
+    /**
+     * Adds a definition object to the cache
+     */
+    function add($def, $config) {
+        trigger_error('Cannot call abstract method', E_USER_ERROR);
+    }
+    
+    /**
+     * Unconditionally saves a definition object to the cache
+     */
+    function set($def, $config) {
+        trigger_error('Cannot call abstract method', E_USER_ERROR);
+    }
+    
+    /**
+     * Replace an object in the cache
+     */
+    function replace($def, $config) {
+        trigger_error('Cannot call abstract method', E_USER_ERROR);
+    }
+    
+    /**
+     * Retrieves a definition object from the cache
+     */
+    function get($config) {
+        trigger_error('Cannot call abstract method', E_USER_ERROR);
+    }
+    
+    /**
+     * Removes a definition object to the cache
+     */
+    function remove($config) {
+        trigger_error('Cannot call abstract method', E_USER_ERROR);
+    }
+    
+    /**
+     * Clears all objects from cache
+     */
+    function flush($config) {
+        trigger_error('Cannot call abstract method', E_USER_ERROR);
+    }
+    
+    /**
+     * Clears all expired (older version or revision) objects from cache
+     */
+    function cleanup($config) {
+        trigger_error('Cannot call abstract method', E_USER_ERROR);
+    }
+}
+
+?>