array( * 'class' => 'yii\web\DbSession', * // 'db' => 'mydb', * // 'sessionTable' => 'my_session', * ) * ~~~ * * @author Qiang Xue * @since 2.0 */ class DbSession extends Session { /** * @var Connection|string the DB connection object or the application component ID of the DB connection. * After the DbSession object is created, if you want to change this property, you should only assign it * with a DB connection object. */ public $db = 'db'; /** * @var string the name of the DB table that stores the session data. * The table should be pre-created as follows: * * ~~~ * CREATE TABLE tbl_session * ( * id CHAR(40) NOT NULL PRIMARY KEY, * expire INTEGER, * data BLOB * ) * ~~~ * * where 'BLOB' refers to the BLOB-type of your preferred DBMS. Below are the BLOB type * that can be used for some popular DBMS: * * - MySQL: LONGBLOB * - PostgreSQL: BYTEA * - MSSQL: BLOB * * When using DbSession in a production server, we recommend you create a DB index for the 'expire' * column in the session table to improve the performance. */ public $sessionTable = 'tbl_session'; /** * Initializes the DbSession component. * This method will initialize the [[db]] property to make sure it refers to a valid DB connection. * @throws InvalidConfigException if [[db]] is invalid. */ public function init() { if (is_string($this->db)) { $this->db = Yii::$app->getComponent($this->db); } if (!$this->db instanceof Connection) { throw new InvalidConfigException("DbSession::db must be either a DB connection instance or the application component ID of a DB connection."); } 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; } /** * Updates the current session ID with a newly generated one . * Please refer to [[http://php.net/session_regenerate_id]] for more details. * @param boolean $deleteOldSession Whether to delete the old associated session file or not. */ public function regenerateID($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(); $query = new Query; $row = $query->from($this->sessionTable) ->where(array('id' => $oldID)) ->createCommand($this->db) ->queryRow(); if ($row !== false) { if ($deleteOldSession) { $this->db->createCommand() ->update($this->sessionTable, array('id' => $newID), array('id' => $oldID)) ->execute(); } else { $row['id'] = $newID; $this->db->createCommand() ->insert($this->sessionTable, $row) ->execute(); } } else { // shouldn't reach here normally $this->db->createCommand() ->insert($this->sessionTable, array( 'id' => $newID, 'expire' => time() + $this->getTimeout(), ))->execute(); } } /** * Session read handler. * Do not call this method directly. * @param string $id session ID * @return string the session data */ public function readSession($id) { $query = new Query; $data = $query->select(array('data')) ->from($this->sessionTable) ->where('[[expire]]>:expire AND [[id]]=:id', array(':expire' => time(), ':id' => $id)) ->createCommand($this->db) ->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(); $query = new Query; $exists = $query->select(array('id')) ->from($this->sessionTable) ->where(array('id' => $id)) ->createCommand($this->db) ->queryScalar(); if ($exists === false) { $this->db->createCommand() ->insert($this->sessionTable, array( 'id' => $id, 'data' => $data, 'expire' => $expire, ))->execute(); } else { $this->db->createCommand() ->update($this->sessionTable, array('data' => $data, 'expire' => $expire), array('id' => $id)) ->execute(); } } 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) { $this->db->createCommand() ->delete($this->sessionTable, array('id' => $id)) ->execute(); 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) { $this->db->createCommand() ->delete($this->sessionTable, '[[expire]]<:expire', array(':expire' => time())) ->execute(); return true; } }