#680 - implementation of TMemCacheSession

1 files changed, 293 insertions, 0 deletions

diff --git a/framework/Web/TMemCacheSession.php b/framework/Web/TMemCacheSession.php
new file mode 100644
index 00000000..3b3bd4d7
--- /dev/null
+++ b/framework/Web/TMemCacheSession.php
@@ -0,0 +1,293 @@
+<?php
+
+/**
+ * TMemCacheSession class
+ *
+ * @author Carl G. Mathisen <carlgmathisen@gmail.com>
+ * @link http://www.pradosoft.com/
+ * @copyright Copyright &copy; 2007 PradoSoft
+ * @license http://www.pradosoft.com/license/
+ * @version $Id: TMemCacheSession.php $
+ * @package System.Web
+ */
+
+/**
+ * TMemCacheSession class
+ *
+ * TMemCacheSession provides access for storing sessions in memcache.
+ * Beware, session data will be stored in memory. Old data will be flushed
+ * if you run out of cache memory.  Configure your memcache carefully.
+ * Keep in mind that memcached is a cache not a database. It is fast,
+ * but not reliable storage.
+ *
+ * <module id="session" class="TMemCacheSession" SessionName="SSID"
+ *         CookieMode="Allow" AutoStart="true" GCProbability="1"
+ *         UseTransparentSessionID="true" TimeOut="3600" />
+ *     <server Host="hostname1" Port="11211" />
+ *     <server Host="hostname2" Port="11211" Weight="1" Timeout="1" RetryInterval="15" Persistent="true" />
+ * </module>
+ * 
+ * @author Carl G. Mathisen <carlgmathisen@gmail.com>
+ * @version $Id: TMemCacheSession.php $
+ * @package System.Web
+ * @since 3.1.0
+ */
+class TMemCacheSession extends THttpSession
+{		
+	/**
+	 * @var MemCache
+	 */
+	private $_memCache=null;
+	
+	/**
+	 * @var boolean if the module is initialized
+	 */
+	private $_initialized=false;
+	
+	/**
+	 * File extension of external configuration file
+	 */
+	const CONFIG_FILE_EXT='.xml';
+	
+	/**
+	 * @var array list of servers available
+	 */
+	private $_servers=array();
+	
+	/**
+	 * @var string external configuration file
+	 */
+	private $_configFile=null;
+	
+	/**
+	 * @var string 
+	 */
+	private $_prefix = 'PRADO';
+	
+	/**
+	 * @var string
+	 */
+	private $_host = 'localhost';
+	
+	/**
+	 * @var integer
+	 */
+	private $_port = 11211;
+
+    /**
+     * Connecting to memcached. If no servers are defined in config, we will use
+   	 *the default server {@see Host} and {@see Port}, localhost and 11211 respectively.
+     */
+    public function init($config)
+    {
+        $this->setAutoStart(true);
+        $this->setUseCustomStorage(true);
+        if(!extension_loaded('memcache'))
+			throw new TConfigurationException('memcache_extension_required');
+        if($this->_configFile!==null)
+		{
+ 			if(is_file($this->_configFile))
+ 			{
+				$dom=new TXmlDocument;
+				$dom->loadFromFile($this->_configFile);
+				$this->loadConfig($dom);
+			}
+			else
+				throw new TConfigurationException('memcachesession_configfile_invalid',$this->_configFile);
+		}
+		$this->loadConfig($config);
+        $this->_memCache = new MemCache;
+        if(count($this->_servers))
+        {
+            foreach($this->_servers as $server)
+            {
+                Prado::trace('Adding server '.$server['Host'].' from serverlist', 'System.Web.TMemCacheSession');
+                if($this->_memCache->addServer($server['Host'],$server['Port'],$server['Persistent'],
+                    $server['Weight'],$server['Timeout'],$server['RetryInterval'])===false)
+                    throw new TConfigurationException('memcache_connection_failed',$server['Host'],$server['Port']);
+            }
+        }
+        else
+        {
+            Prado::trace('Adding server '.$this->_host.' from serverlist', 'System.Web.TMemCacheSession');
+            if($this->_memCache->addServer($this->_host,$this->_port)===false)
+                throw new TConfigurationException('memcache_connection_failed',$this->_host,$this->_port);
+        }
+        $this->_initialized=true;
+    }
+    
+    /**
+	 * Loads configuration from an XML element
+	 * @param TXmlElement configuration node
+	 * @throws TConfigurationException if log route class or type is not specified
+	 */
+	private function loadConfig($xml)
+	{
+	    if($xml instanceof TXmlElement)
+	    {
+	    	foreach($xml->getElementsByTagName('server') as $serverConfig)
+    		{
+    			$properties=$serverConfig->getAttributes();
+    			if(($host=$properties->remove('Host'))===null)
+    				throw new TConfigurationException('memcachesession_serverhost_required');
+    			if(($port=$properties->remove('Port'))===null)
+        			throw new TConfigurationException('memcachesession_serverport_required');
+        		if(!is_numeric($port))
+        		    throw new TConfigurationException('memcachesession_serverport_invalid');
+        		$server = array('Host'=>$host,'Port'=>$port,'Weight'=>1,'Timeout'=>1800,'RetryInterval'=>15,'Persistent'=>true);
+        		$checks = array(
+        		    'Weight'=>'memcachesession_serverweight_invalid',
+        		    'Timeout'=>'memcachesession_servertimeout_invalid',
+        		    'RetryInterval'=>'memcachesession_serverretryinterval_invalid'
+        		);
+        		foreach($checks as $property=>$exception)
+        		{
+        		    $value=$properties->remove($property); 
+        		    if($value!==null && is_numeric($value))
+        		        $server[$property]=$value;
+        		    else if($value!==null)
+        		        throw new TConfigurationException($exception);
+        		}
+        		$server['Persistent']= TPropertyValue::ensureBoolean($properties->remove('Persistent'));
+    			$this->_servers[]=$server;
+    		}
+	    }
+	}
+
+    /**
+	 * Session open handler.
+	 * @param string session save path
+	 * @param string session name
+	 * @return boolean whether session is opened successfully
+	 */
+	public function _open($savePath,$sessionName)
+	{
+        return true;
+	}
+
+	/**
+	 * Session close handler.
+	 * @return boolean whether session is closed successfully
+	 */
+	public function _close()
+	{
+		return true;
+	}
+
+	/**
+	 * Session read handler.
+	 * @param string session ID
+	 * @return string the session data
+	 */
+	public function _read($id)
+	{
+	    $key = $this->calculateKey($id);
+	    return $this->_memCache->get($key);
+	}
+
+	/**
+	 * Session write handler.
+	 * @param string session ID
+	 * @param string session data
+	 * @return boolean whether session write is successful
+	 */
+	public function _write($id,$data)
+	{
+		$key = $this->calculateKey($id);
+		$res = $this->_memCache->set($key,$data,MEMCACHE_COMPRESSED,$this->_timeOut);
+	    return $res;
+	}
+
+	/**
+	 * Session destroy handler.
+	 * This method should be overriden if {@link setUseCustomStorage UseCustomStorage} is set true.
+	 * @param string session ID
+	 * @return boolean whether session is destroyed successfully
+	 */
+	public function _destroy($id)
+	{
+	    $key = $this->calculateKey($id);
+	    return $this->_memCache->delete($key);
+	}
+
+	/**
+	 * Session GC (garbage collection) handler.
+	 * Memcache has it's own garbage collection
+	 * @param integer the number of seconds after which data will be seen as 'garbage' and cleaned up.
+	 * @return boolean whether session is GCed successfully
+	 */
+	public function _gc($maxLifetime)
+	{
+		return true;
+	}
+	
+	/**
+	 * @return string host name of the memcache server
+	 */
+	public function getHost()
+	{
+		return $this->_host;
+	}
+
+	/**
+	 * @param string host name of the memcache server
+	 * @throws TInvalidOperationException if the module is already initialized
+	 */
+	public function setHost($value)
+	{
+		if($this->_initialized)
+			throw new TInvalidOperationException('memcache_host_unchangeable');
+		else
+			$this->_host=$value;
+	}
+
+	/**
+	 * @return integer port number of the memcache server
+	 */
+	public function getPort()
+	{
+		return $this->_port;
+	}
+
+	/**
+	 * @param integer port number of the memcache server
+	 * @throws TInvalidOperationException if the module is already initialized
+	 */
+	public function setPort($value)
+	{
+		if($this->_initialized)
+			throw new TInvalidOperationException('memcache_port_unchangeable');
+		else
+			$this->_port=TPropertyValue::ensureInteger($value);
+	}
+
+    /**
+     * @param string prefix of our memcache data key
+     */
+	public function setPrefix($value)
+	{
+	    if($this->_initialized)
+			throw new TInvalidOperationException('memcache_prefix_unchangeable');
+		else
+	    $this->_prefix = $value;
+	}
+	
+	/**
+	 * @return string prefix of our memcache data key
+	 */
+	public function getPrefix()
+	{
+	    return $this->_prefix;
+	}
+	
+	/**
+	 * @param string memcache data key
+	 * @return safe memcache key within 256 characters
+	 */
+	private function calculateKey($key)
+	{
+	    return md5($this->_prefix.$key);
+	}
+}
+
+?>
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