A cached database authorization manager for Yii.

CachedDbAuthManager.php

<?php

class CachedDbAuthManager extends CDbAuthManager
{
  const CACHE_KEY_PREFIX = 'Auth.CachedDbAuthManager.';

	/**
	 * @var integer the time in seconds that the messages can remain valid in cache.
	 * Defaults to 0, meaning the caching is disabled.
	 */
	public $cachingDuration = 0;
	/**
	 * @var string the ID of the cache application component that is used to cache the messages.
	 * Defaults to 'cache' which refers to the primary cache application component.
	 * Set this property to false if you want to disable caching the permissions.
	 */
	public $cacheID = 'cache';

	/**
	 * Performs access check for the specified user.
	 * @param string $itemName the name of the operation that need access check.
	 * @param integer $userId the user id.
	 * @param array $params name-value pairs that would be passed to biz rules associated
	 * with the tasks and roles assigned to the user.
	 * @param boolean $allowCaching whether to allow caching the result of access check.
	 * @return boolean whether the operations can be performed by the user.
	 */
	public function checkAccess($itemName, $userId, $params = array(), $allowCaching = true)
	{
		$key = $this->resolveCacheKey($itemName, $userId, $params);

		/* @var $cache CCache */
		if ($allowCaching && $this->cachingDuration > 0 && $this->cacheID !== false
				&& ($cache = Yii::app()->getComponent($this->cacheID)) !== null)
		{
			if (($data = $cache->get($key)) !== false)
				return unserialize($data);
		}

		$result = parent::checkAccess($itemName, $userId, $params);;

		if (isset($cache))
			$cache->set($key, serialize($result), $this->cachingDuration);

		return $result;
	}

	/**
	 * Flushes the access cache for the specified user.
	 * @param string $itemName the name of the operation that need access check.
	 * @param mixed $userId the user id.
	 * @param array $params name-value pairs that would be passed to biz rules associated
	 * with the tasks and roles assigned to the user.
	 */
	public function flushAccess($itemName, $userId, $params = array())
	{
		/* @var $cache CCache */
		if ($this->cachingDuration > 0 && $this->cacheID !== false
				&& ($cache = Yii::app()->getComponent($this->cacheID)) !== null)
		{
			$key = $this->resolveCacheKey($itemName, $userId, $params);
			$cache->delete($key);
		}
	}

	/**
	 * Returns the key to use when caching.
	 * @param string $itemName the name of the operation that need access check.
	 * @param integer $userId the user id.
	 * @param array $params name-value pairs that would be passed to biz rules associated
	 * with the tasks and roles assigned to the user.
	 * @return string the key.
	 */
	protected function resolveCacheKey($itemName, $userId, $params)
	{
		return self::CACHE_KEY_PREFIX . '.' . $itemName . '.' . $userId . '.' . serialize($params);
	}
}