session WIP

framework/web/CacheSession.php

+<?php
+/**
+ * DbSession class file.
+ *
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright &copy; 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\web;
+
+/**
+ * CacheSession implements a session component using cache as storage medium.
+ *
+ * The cache being used can be any cache application component implementing {@link ICache} interface.
+ * The ID of the cache application component is specified via {@link cacheID}, which defaults to 'cache'.
+ *
+ * Beware, by definition cache storage are volatile, which means the data stored on them
+ * may be swapped out and get lost. Therefore, you must make sure the cache used by this component
+ * is NOT volatile. If you want to use {@link CDbCache} as storage medium, use {@link CDbHttpSession}
+ * is a better choice.
+ *
+ * @property boolean $useCustomStorage Whether to use custom storage.
+ *
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @package system.web
+ * @since 1.0
+ */
+class CacheSession extends Session
+{
+	/**
+	 * Prefix to the keys for storing cached data
+	 */
+	const CACHE_KEY_PREFIX = 'Yii.CacheSession.';
+	/**
+	 * @var string the ID of the cache application component. Defaults to 'cache' (the primary cache application component.)
+	 */
+	public $cacheID = 'cache';
+
+	/**
+	 * @var ICache the cache component
+	 */
+	private $_cache;
+
+	/**
+	 * Initializes the application component.
+	 * This method overrides the parent implementation by checking if cache is available.
+	 */
+	public function init()
+	{
+		$this->_cache = Yii::app()->getComponent($this->cacheID);
+		if (!($this->_cache instanceof ICache)) {
+			throw new CException(Yii::t('yii', 'CacheSession.cacheID is invalid. Please make sure "{id}" refers to a valid cache application component.',
+				array('{id}' => $this->cacheID)));
+		}
+		parent::init();
+	}
+
+	/**
+	 * Returns a value indicating whether to use custom session storage.
+	 * This method overrides the parent implementation and always returns true.
+	 * @return boolean whether to use custom storage.
+	 */
+	public function getUseCustomStorage()
+	{
+		return true;
+	}
+
+	/**
+	 * Session read handler.
+	 * Do not call this method directly.
+	 * @param string $id session ID
+	 * @return string the session data
+	 */
+	public function readSession($id)
+	{
+		$data = $this->_cache->get($this->calculateKey($id));
+		return $data === false ? '' : $data;
+	}
+
+	/**
+	 * Session write handler.
+	 * Do not call this method directly.
+	 * @param string $id session ID
+	 * @param string $data session data
+	 * @return boolean whether session write is successful
+	 */
+	public function writeSession($id, $data)
+	{
+		return $this->_cache->set($this->calculateKey($id), $data, $this->getTimeout());
+	}
+
+	/**
+	 * Session destroy handler.
+	 * Do not call this method directly.
+	 * @param string $id session ID
+	 * @return boolean whether session is destroyed successfully
+	 */
+	public function destroySession($id)
+	{
+		return $this->_cache->delete($this->calculateKey($id));
+	}
+
+	/**
+	 * Generates a unique key used for storing session data in cache.
+	 * @param string $id session variable name
+	 * @return string a safe cache key associated with the session variable name
+	 */
+	protected function calculateKey($id)
+	{
+		return self::CACHE_KEY_PREFIX . $id;
+	}
+}

framework/web/DbSession.php

+<?php
+/**
+ * DbSession class file.
+ *
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright &copy; 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\web;
+
+/**
+ * DbSession extends {@link CHttpSession} by using database as session data storage.
+ *
+ * DbSession stores session data in a DB table named 'YiiSession'. The table name
+ * can be changed by setting {@link sessionTableName}. If the table does not exist,
+ * it will be automatically created if {@link autoCreateSessionTable} is set true.
+ *
+ * The following is the table structure:
+ *
+ * <pre>
+ * CREATE TABLE YiiSession
+ * (
+ *     id CHAR(32) PRIMARY KEY,
+ *     expire INTEGER,
+ *     data BLOB
+ * )
+ * </pre>
+ * Where 'BLOB' refers to the BLOB-type of your preffered database.
+ *
+ * DbSession relies on {@link http://www.php.net/manual/en/ref.pdo.php PDO} to access database.
+ *
+ * By default, it will use an SQLite3 database named 'session-YiiVersion.db' under the application runtime directory.
+ * You can also specify {@link connectionID} so that it makes use of a DB application component to access database.
+ *
+ * When using DbSession in a production server, we recommend you pre-create the session DB table
+ * and set {@link autoCreateSessionTable} to be false. This will greatly improve the performance.
+ * You may also create a DB index for the 'expire' column in the session table to further improve the performance.
+ *
+ * @property boolean $useCustomStorage Whether to use custom storage.
+ *
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @package system.web
+ * @since 1.0
+ */
+class DbSession extends Session
+{
+	/**
+	 * @var string the ID of a {@link CDbConnection} application component. If not set, a SQLite database
+	 * will be automatically created and used. The SQLite database file is
+	 * is <code>protected/runtime/session-YiiVersion.db</code>.
+	 */
+	public $connectionID;
+	/**
+	 * @var string the name of the DB table to store session content.
+	 * Note, if {@link autoCreateSessionTable} is false and you want to create the DB table manually by yourself,
+	 * you need to make sure the DB table is of the following structure:
+	 * <pre>
+	 * (id CHAR(32) PRIMARY KEY, expire INTEGER, data BLOB)
+	 * </pre>
+	 * @see autoCreateSessionTable
+	 */
+	public $sessionTableName = 'YiiSession';
+	/**
+	 * @var boolean whether the session DB table should be automatically created if not exists. Defaults to true.
+	 * @see sessionTableName
+	 */
+	public $autoCreateSessionTable = true;
+	/**
+	 * @var CDbConnection the DB connection instance
+	 */
+	private $_db;
+
+
+	/**
+	 * Returns a value indicating whether to use custom session storage.
+	 * This method overrides the parent implementation and always returns true.
+	 * @return boolean whether to use custom storage.
+	 */
+	public function getUseCustomStorage()
+	{
+		return true;
+	}
+
+	/**
+	 * Updates the current session id with a newly generated one.
+	 * Please refer to {@link http://php.net/session_regenerate_id} for more details.
+	 * @param boolean $deleteOldSession Whether to delete the old associated session file or not.
+	 * @since 1.1.8
+	 */
+	public function regenerateID($deleteOldSession = false)
+	{
+		$oldID = session_id();
+
+		// if no session is started, there is nothing to regenerate
+		if (empty($oldID)) {
+			return;
+		}
+
+		parent::regenerateID(false);
+		$newID = session_id();
+		$db = $this->getDbConnection();
+
+		$row = $db->createCommand()
+			->select()
+			->from($this->sessionTableName)
+			->where('id=:id', array(':id' => $oldID))
+			->queryRow();
+		if ($row !== false) {
+			if ($deleteOldSession) {
+				$db->createCommand()->update($this->sessionTableName, array(
+					'id' => $newID
+				), 'id=:oldID', array(':oldID' => $oldID));
+			} else {
+				$row['id'] = $newID;
+				$db->createCommand()->insert($this->sessionTableName, $row);
+			}
+		} else {
+			// shouldn't reach here normally
+			$db->createCommand()->insert($this->sessionTableName, array(
+				'id' => $newID,
+				'expire' => time() + $this->getTimeout(),
+			));
+		}
+	}
+
+	/**
+	 * Creates the session DB table.
+	 * @param CDbConnection $db the database connection
+	 * @param string $tableName the name of the table to be created
+	 */
+	protected function createSessionTable($db, $tableName)
+	{
+		$driver = $db->getDriverName();
+		if ($driver === 'mysql') {
+			$blob = 'LONGBLOB';
+		} elseif ($driver === 'pgsql') {
+			$blob = 'BYTEA';
+		} else {
+			$blob = 'BLOB';
+		}
+		$db->createCommand()->createTable($tableName, array(
+			'id' => 'CHAR(32) PRIMARY KEY',
+			'expire' => 'integer',
+			'data' => $blob,
+		));
+	}
+
+	/**
+	 * @return CDbConnection the DB connection instance
+	 * @throws CException if {@link connectionID} does not point to a valid application component.
+	 */
+	protected function getDbConnection()
+	{
+		if ($this->_db !== null) {
+			return $this->_db;
+		} elseif (($id = $this->connectionID) !== null) {
+			if (($this->_db = Yii::app()->getComponent($id)) instanceof CDbConnection) {
+				return $this->_db;
+			} else {
+				throw new CException(Yii::t('yii', 'DbSession.connectionID "{id}" is invalid. Please make sure it refers to the ID of a CDbConnection application component.',
+					array('{id}' => $id)));
+			}
+		} else {
+			$dbFile = Yii::app()->getRuntimePath() . DIRECTORY_SEPARATOR . 'session-' . Yii::getVersion() . '.db';
+			return $this->_db = new CDbConnection('sqlite:' . $dbFile);
+		}
+	}
+
+	/**
+	 * Session open handler.
+	 * Do not call this method directly.
+	 * @param string $savePath session save path
+	 * @param string $sessionName session name
+	 * @return boolean whether session is opened successfully
+	 */
+	public function openSession($savePath, $sessionName)
+	{
+		if ($this->autoCreateSessionTable) {
+			$db = $this->getDbConnection();
+			$db->setActive(true);
+			try {
+				$db->createCommand()->delete($this->sessionTableName, 'expire<:expire', array(':expire' => time()));
+			} catch (Exception $e) {
+				$this->createSessionTable($db, $this->sessionTableName);
+			}
+		}
+		return true;
+	}
+
+	/**
+	 * Session read handler.
+	 * Do not call this method directly.
+	 * @param string $id session ID
+	 * @return string the session data
+	 */
+	public function readSession($id)
+	{
+		$data = $this->getDbConnection()->createCommand()
+			->select('data')
+			->from($this->sessionTableName)
+			->where('expire>:expire AND id=:id', array(':expire' => time(), ':id' => $id))
+			->queryScalar();
+		return $data === false ? '' : $data;
+	}
+
+	/**
+	 * Session write handler.
+	 * Do not call this method directly.
+	 * @param string $id session ID
+	 * @param string $data session data
+	 * @return boolean whether session write is successful
+	 */
+	public function writeSession($id, $data)
+	{
+		// exception must be caught in session write handler
+		// http://us.php.net/manual/en/function.session-set-save-handler.php
+		try {
+			$expire = time() + $this->getTimeout();
+			$db = $this->getDbConnection();
+			if ($db->createCommand()->select('id')->from($this->sessionTableName)->where('id=:id', array(':id' => $id))->queryScalar() === false) {
+				$db->createCommand()->insert($this->sessionTableName, array(
+					'id' => $id,
+					'data' => $data,
+					'expire' => $expire,
+				));
+			} else {
+				$db->createCommand()->update($this->sessionTableName, array(
+					'data' => $data,
+					'expire' => $expire
+				), 'id=:id', array(':id' => $id));
+			}
+		} catch (Exception $e) {
+			if (YII_DEBUG) {
+				echo $e->getMessage();
+			}
+			// it is too late to log an error message here
+			return false;
+		}
+		return true;
+	}
+
+	/**
+	 * Session destroy handler.
+	 * Do not call this method directly.
+	 * @param string $id session ID
+	 * @return boolean whether session is destroyed successfully
+	 */
+	public function destroySession($id)
+	{
+		$this->getDbConnection()->createCommand()
+			->delete($this->sessionTableName, 'id=:id', array(':id' => $id));
+		return true;
+	}
+
+	/**
+	 * Session GC (garbage collection) handler.
+	 * Do not call this method directly.
+	 * @param integer $maxLifetime the number of seconds after which data will be seen as 'garbage' and cleaned up.
+	 * @return boolean whether session is GCed successfully
+	 */
+	public function gcSession($maxLifetime)
+	{
+		$this->getDbConnection()->createCommand()
+			->delete($this->sessionTableName, 'expire<:expire', array(':expire' => time()));
+		return true;
+	}
+}

framework/web/SessionIterator.php

+<?php
+/**
+ * SessionIterator class file.
+ *
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright &copy; 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yii\web;
+
+/**
+ * SessionIterator implements an iterator for traversing session variables managed by [[Session]].
+ *
+ * @author Qiang Xue <qiang.xue@gmail.com>
+ * @since 2.0
+ */
+class SessionIterator implements \Iterator
+{
+	/**
+	 * @var array list of keys in the map
+	 */
+	private $_keys;
+	/**
+	 * @var mixed current key
+	 */
+	private $_key;
+
+	/**
+	 * Constructor.
+	 */
+	public function __construct()
+	{
+		$this->_keys = array_keys($_SESSION);
+	}
+
+	/**
+	 * Rewinds internal array pointer.
+	 * This method is required by the interface Iterator.
+	 */
+	public function rewind()
+	{
+		$this->_key = reset($this->_keys);
+	}
+
+	/**
+	 * Returns the key of the current array element.
+	 * This method is required by the interface Iterator.
+	 * @return mixed the key of the current array element
+	 */
+	public function key()
+	{
+		return $this->_key;
+	}
+
+	/**
+	 * Returns the current array element.
+	 * This method is required by the interface Iterator.
+	 * @return mixed the current array element
+	 */
+	public function current()
+	{
+		return isset($_SESSION[$this->_key]) ? $_SESSION[$this->_key] : null;
+	}
+
+	/**
+	 * Moves the internal pointer to the next array element.
+	 * This method is required by the interface Iterator.
+	 */
+	public function next()
+	{
+		do {
+			$this->_key = next($this->_keys);
+		} while (!isset($_SESSION[$this->_key]) && $this->_key !== false);
+	}
+
+	/**
+	 * Returns whether there is an element at current position.
+	 * This method is required by the interface Iterator.
+	 * @return boolean
+	 */
+	public function valid()
+	{
+		return $this->_key !== false;
+	}
+}