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