1: <?php
  2: /**
  3:  * Database Session save handler.  Allows saving session information into a model.
  4:  *
  5:  * PHP 5
  6:  *
  7:  * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
  8:  * Copyright 2005-2012, Cake Software Foundation, Inc. (http://cakefoundation.org)
  9:  *
 10:  * Licensed under The MIT License
 11:  * Redistributions of files must retain the above copyright notice.
 12:  *
 13:  * @copyright     Copyright 2005-2012, Cake Software Foundation, Inc. (http://cakefoundation.org)
 14:  * @link          http://cakephp.org CakePHP(tm) Project
 15:  * @package       Cake.Model.Datasource.Session
 16:  * @since         CakePHP(tm) v 2.0
 17:  * @license       MIT License (http://www.opensource.org/licenses/mit-license.php)
 18:  */
 19: 
 20: App::uses('CakeSessionHandlerInterface', 'Model/Datasource/Session');
 21: App::uses('ClassRegistry', 'Utility');
 22: 
 23: /**
 24:  * DatabaseSession provides methods to be used with CakeSession.
 25:  *
 26:  * @package       Cake.Model.Datasource.Session
 27:  */
 28: class DatabaseSession implements CakeSessionHandlerInterface {
 29: 
 30: /**
 31:  * Reference to the model handling the session data
 32:  *
 33:  * @var Model
 34:  */
 35:     protected $_model;
 36: 
 37: /**
 38:  * Number of seconds to mark the session as expired
 39:  *
 40:  * @var int
 41:  */
 42:     protected $_timeout;
 43: 
 44: /**
 45:  * Constructor.  Looks at Session configuration information and
 46:  * sets up the session model.
 47:  *
 48:  */
 49:     public function __construct() {
 50:         $modelName = Configure::read('Session.handler.model');
 51: 
 52:         if (empty($modelName)) {
 53:             $settings = array(
 54:                 'class' => 'Session',
 55:                 'alias' => 'Session',
 56:                 'table' => 'cake_sessions',
 57:             );
 58:         } else {
 59:             $settings = array(
 60:                 'class' => $modelName,
 61:                 'alias' => 'Session',
 62:             );
 63:         }
 64:         $this->_model = ClassRegistry::init($settings);
 65:         $this->_timeout = Configure::read('Session.timeout') * 60;
 66:     }
 67: 
 68: /**
 69:  * Method called on open of a database session.
 70:  *
 71:  * @return boolean Success
 72:  */
 73:     public function open() {
 74:         return true;
 75:     }
 76: 
 77: /**
 78:  * Method called on close of a database session.
 79:  *
 80:  * @return boolean Success
 81:  */
 82:     public function close() {
 83:         $probability = mt_rand(1, 150);
 84:         if ($probability <= 3) {
 85:             $this->gc();
 86:         }
 87:         return true;
 88:     }
 89: 
 90: /**
 91:  * Method used to read from a database session.
 92:  *
 93:  * @param mixed $id The key of the value to read
 94:  * @return mixed The value of the key or false if it does not exist
 95:  */
 96:     public function read($id) {
 97:         $row = $this->_model->find('first', array(
 98:             'conditions' => array($this->_model->primaryKey => $id)
 99:         ));
100: 
101:         if (empty($row[$this->_model->alias]['data'])) {
102:             return false;
103:         }
104: 
105:         return $row[$this->_model->alias]['data'];
106:     }
107: 
108: /**
109:  * Helper function called on write for database sessions.
110:  *
111:  * @param integer $id ID that uniquely identifies session in database
112:  * @param mixed $data The value of the data to be saved.
113:  * @return boolean True for successful write, false otherwise.
114:  */
115:     public function write($id, $data) {
116:         if (!$id) {
117:             return false;
118:         }
119:         $expires = time() + $this->_timeout;
120:         $record = compact('id', 'data', 'expires');
121:         $record[$this->_model->primaryKey] = $id;
122:         return $this->_model->save($record);
123:     }
124: 
125: /**
126:  * Method called on the destruction of a database session.
127:  *
128:  * @param integer $id ID that uniquely identifies session in database
129:  * @return boolean True for successful delete, false otherwise.
130:  */
131:     public function destroy($id) {
132:         return $this->_model->delete($id);
133:     }
134: 
135: /**
136:  * Helper function called on gc for database sessions.
137:  *
138:  * @param integer $expires Timestamp (defaults to current time)
139:  * @return boolean Success
140:  */
141:     public function gc($expires = null) {
142:         if (!$expires) {
143:             $expires = time();
144:         }
145:         return $this->_model->deleteAll(array($this->_model->alias . ".expires <" => $expires), false, false);
146:     }
147: 
148: /**
149:  * Closes the session before the objects handling it become unavailable
150:  *
151:  * @return void
152:  */
153:     public function __destruct() {
154:         try {
155:             session_write_close();
156:         } catch (Exception $e) {
157:         }
158:     }
159: 
160: }
161: