Added TCacheHttpSession

1 files changed, 151 insertions, 0 deletions

diff --git a/framework/Web/TCacheHttpSession.php b/framework/Web/TCacheHttpSession.php
new file mode 100644
index 00000000..edc79935
--- /dev/null
+++ b/framework/Web/TCacheHttpSession.php
@@ -0,0 +1,151 @@
+<?php
+/**
+ * TCacheHttpSession class
+ *
+ * @author Carl G. Mathisen <carlgmathisen@gmail.com>
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @link http://www.pradosoft.com/
+ * @copyright Copyright &copy; 2005-2007 PradoSoft
+ * @license http://www.pradosoft.com/license/
+ * @version $Id$
+ * @package System.Web
+ * @since 3.1.1
+ */
+
+/**
+ * TCacheHttpSession class
+ *
+ * TCacheHttpSession provides access for storing session data using a cache module (e.g. TMemCache, TDbCache).
+ * To specify the cache module for data storage, set the {@link setCacheModuleID CacheModuleID} property
+ * which should refer to a valid cache module configured in the application configuration.
+ *
+ * The following example shows how we configure TCacheHttpSession:
+ * <code>
+ *  <modules>
+ *    <module id="cache" class="System.Caching.TMemCache" Host="localhost" Port="11211" />
+ *    <module id="session" class="System.Web.TCacheHttpSession"
+ *         CacheModuleID="cache" SessionName="SSID"
+ *         CookieMode="Allow" AutoStart="true" GCProbability="1"
+ *         UseTransparentSessionID="true" TimeOut="3600" />
+ *  </modules>
+ * </code>
+ *
+ * Beware, by definition cache storage are volatile, which means the data stored on them
+ * may be swapped out and get lost. This may not be the case for certain cache storage,
+ * such as database. So make sure you manage your cache properly to avoid loss of session data.
+ *
+ * @author Carl G. Mathisen <carlgmathisen@gmail.com>
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @version $Id$
+ * @package System.Web
+ * @since 3.1.1
+ */
+class TCacheHttpSession extends THttpSession
+{
+	private $_prefix='session';
+	private $_cacheModuleID='';
+	private $_cache;
+
+	/**
+	 * Initializes the module.
+	 * This method is required by IModule.
+	 * It reads the CacheModule property.
+	 * @param TXmlElement module configuration
+	 */
+    public function init($config)
+    {
+		if($this->_cacheModuleID==='')
+			throw new TConfigurationException('cachesession_cachemoduleid_required');
+		else if(($cache=$this->getApplication()->getModule($this->_cacheModuleID))===null)
+			throw new TConfigurationException('cachesession_cachemodule_inexistent',$this->_cacheModuleID);
+		else if($cache instanceof ICache)
+			$this->_cache=$cache;
+		else
+			throw new TConfigurationException('cachesession_cachemodule_invalid',$this->_cacheModuleID);
+		$this->setUseCustomStorage(true);
+		parent::init($config);
+    }
+
+	/**
+	 * @return string host name of the memcache server
+	 */
+	public function getCacheModuleID()
+	{
+		return $this->_cacheModuleID;
+	}
+
+	/**
+	 * @param string the ID of the cache module.
+	 */
+	public function setCacheModuleID($value)
+	{
+		$this->_cacheModuleID=$value;
+	}
+
+	/**
+	 * @return ICache the cache module being used for data storage
+	 */
+	public function getCache()
+	{
+		return $this->_cache;
+	}
+
+	/**
+	 * Session read handler.
+	 * @param string session ID
+	 * @return string the session data
+	 */
+	public function _read($id)
+	{
+	    return $this->_cache->get($this->calculateKey($id));
+	}
+
+	/**
+	 * Session write handler.
+	 * @param string session ID
+	 * @param string session data
+	 * @return boolean whether session write is successful
+	 */
+	public function _write($id,$data)
+	{
+		return $this->_cache->set($this->calculateKey($id),$data);
+	}
+
+	/**
+	 * Session destroy handler.
+	 * This method should be overriden if {@link setUseCustomStorage UseCustomStorage} is set true.
+	 * @param string session ID
+	 * @return boolean whether session is destroyed successfully
+	 */
+	public function _destroy($id)
+	{
+	    return $this->_cache->delete($this->calculateKey($id));
+	}
+
+	/**
+	 * @return string prefix of session variable name to avoid conflict with other cache data. Defaults to 'session'.
+	 */
+	public function getKeyPrefix()
+	{
+	    return $this->_prefix;
+	}
+
+	/**
+     * @param string prefix of session variable name to avoid conflict with other cache data
+     */
+	public function setKeyPrefix($value)
+	{
+	    $this->_prefix=$value;
+	}
+
+	/**
+	 * @param string session variable name
+	 * @return string a safe cache key associated with the session variable name
+	 */
+	protected function calculateKey($id)
+	{
+	    return $this->_prefix.':'.$id;
+	}
+}
+
+?>
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