/moodle/lib/htmlpurifier/HTMLPurifier/DefinitionCache.php
PHP | 131 lines | 57 code | 16 blank | 58 comment | 7 complexity | 7abf1693729adbb8a0264dac79192c54 MD5 | raw file
Possible License(s): GPL-2.0, LGPL-2.1, BSD-3-Clause, LGPL-2.0
- <?php
- require_once 'HTMLPurifier/DefinitionCache/Serializer.php';
- require_once 'HTMLPurifier/DefinitionCache/Null.php';
- require_once 'HTMLPurifier/DefinitionCache/Decorator.php';
- require_once 'HTMLPurifier/DefinitionCache/Decorator/Memory.php';
- require_once 'HTMLPurifier/DefinitionCache/Decorator/Cleanup.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
- $config->getBatchSerial($this->type) . '-' .
- $config->get($this->type, 'DefinitionRev');
- }
-
- /**
- * 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, $config) {
- if (substr_count($key, '-') < 2) return true;
- list($version, $hash, $revision) = explode('-', $key, 3);
- $compare = version_compare($version, $config->version);
- // version mismatch, is always old
- if ($compare != 0) return true;
- // versions match, ids match, check revision number
- if (
- $hash == $config->getBatchSerial($this->type) &&
- $revision < $config->get($this->type, 'DefinitionRev')
- ) return true;
- return false;
- }
-
- /**
- * 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
- * @note Be carefuly implementing this method as flush. Flush must
- * not interfere with other Definition types, and cleanup()
- * should not be repeatedly called by userland code.
- */
- function cleanup($config) {
- trigger_error('Cannot call abstract method', E_USER_ERROR);
- }
- }