1: <?php
  2: /**
  3:  * SessionHandler storage implementation for SQL databases.
  4:  *
  5:  * Uses the following SQL table structure:
  6:  * <pre>
  7:  * CREATE TABLE horde_sessionhandler (
  8:  *     VARCHAR(32) NOT NULL,
  9:  *     session_lastmodified   INT NOT NULL,
 10:  *     session_data           LONGBLOB,
 11:  *     -- Or, on some DBMS systems:
 12:  *     --  session_data           IMAGE,
 13:  *
 14:  *     PRIMARY KEY (session_id)
 15:  * );
 16:  *
 17:  * CREATE INDEX session_lastmodified_idx ON horde_sessionhandler (session_lastmodified);
 18:  * </pre>
 19:  *
 20:  * Copyright 2002-2012 Horde LLC (http://www.horde.org/)
 21:  *
 22:  * See the enclosed file COPYING for license information (LGPL). If you
 23:  * did not receive this file, see http://www.horde.org/licenses/lgpl21.
 24:  *
 25:  * @author   Mike Cochrane <mike@graftonhall.co.nz>
 26:  * @category Horde
 27:  * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
 28:  * @package  SessionHandler
 29:  */
 30: class Horde_SessionHandler_Storage_Sql extends Horde_SessionHandler_Storage
 31: {
 32:     /**
 33:      * Handle for the current database connection.
 34:      *
 35:      * @var Horde_Db_Adapter
 36:      */
 37:     protected $_db;
 38: 
 39:     /**
 40:      * Constructor.
 41:      *
 42:      * @param array $params  Parameters:
 43:      * <pre>
 44:      * 'db' - (Horde_Db_Adapter) [REQUIRED] The DB instance.
 45:      * 'table' - (string) The name of the sessions table.
 46:      *           DEFAULT: 'horde_sessionhandler'
 47:      * </pre>
 48:      *
 49:      * @throws InvalidArgumentException
 50:      */
 51:     public function __construct(array $params = array())
 52:     {
 53:         if (!isset($params['db'])) {
 54:             throw new InvalidArgumentException('Missing db parameter.');
 55:         }
 56:         $this->_db = $params['db'];
 57:         unset($params['db']);
 58: 
 59:         parent::__construct(array_merge(array(
 60:             'table' => 'horde_sessionhandler'
 61:         ), $params));
 62:     }
 63: 
 64:     /**
 65:      */
 66:     public function open($save_path = null, $session_name = null)
 67:     {
 68:     }
 69: 
 70:     /**
 71:      */
 72:     public function close()
 73:     {
 74:         /* Close any open transactions. */
 75:         if ($this->_db->transactionStarted()) {
 76:             try {
 77:                 $this->_db->commitDbTransaction();
 78:             } catch (Horde_Db_Exception $e) {
 79:                 return false;
 80:             }
 81:         }
 82:         return true;
 83:     }
 84: 
 85:     /**
 86:      */
 87:     public function read($id)
 88:     {
 89:         /* Begin a transaction. */
 90:         // TODO: Rowlocking in Mysql
 91:         if (!$this->_db->transactionStarted()) {
 92:             $this->_db->beginDbTransaction();
 93:         }
 94: 
 95:         /* Build query. */
 96:         $query = sprintf('SELECT session_data FROM %s WHERE session_id = ?',
 97:                          $this->_params['table']);
 98:         $values = array($id);
 99: 
100:         /* Execute the query. */
101:         try {
102:             $columns = $this->_db->columns($this->_params['table']);
103:             return $columns['session_data']->binaryToString(
104:                 $this->_db->selectValue($query, $values));
105:         } catch (Horde_Db_Exception $e) {
106:             return '';
107:         }
108:     }
109: 
110:     /**
111:      */
112:     public function write($id, $session_data)
113:     {
114:         if (!$this->_db->isActive()) {
115:             $this->_db->reconnect();
116:             $this->_db->beginDbTransaction();
117:         }
118: 
119:         /* Check if session exists. */
120:         try {
121:             $exists = $this->_db->selectValue(
122:                 sprintf('SELECT 1 FROM %s WHERE session_id = ?',
123:                         $this->_params['table']),
124:                 array($id));
125:         } catch (Horde_Db_Exception $e) {
126:             return false;
127:         }
128: 
129:         /* Update or insert session data. */
130:         $session_data = new Horde_Db_Value_Binary($session_data);
131:         try {
132:             if ($exists) {
133:                 $query = sprintf(
134:                     'UPDATE %s '
135:                     . 'SET session_data = ?, session_lastmodified = ? '
136:                     . 'WHERE session_id = ?',
137:                     $this->_params['table']);
138:                 $values = array(
139:                     $session_data,
140:                     time(),
141:                     $id
142:                 );
143:                 $this->_db->update($query, $values);
144:             } else {
145:                 $query = sprintf(
146:                     'INSERT INTO %s '
147:                     . '(session_id, session_data, session_lastmodified) '
148:                     . 'VALUES (?, ?, ?)',
149:                     $this->_params['table']);
150:                 $values = array(
151:                     $id,
152:                     $session_data,
153:                     time()
154:                 );
155:                 $this->_db->insert($query, $values);
156:             }
157:             $this->_db->commitDbTransaction();
158:         } catch (Horde_Db_Exception $e) {
159:             try {
160:                 $this->_db->rollbackDbTransaction();
161:             } catch (Horde_Db_Exception $e) {
162:             }
163:             return false;
164:         }
165: 
166:         return true;
167:     }
168: 
169:     /**
170:      */
171:     public function destroy($id)
172:     {
173:         /* Build the SQL query. */
174:         $query = sprintf('DELETE FROM %s WHERE session_id = ?',
175:                          $this->_params['table']);
176:         $values = array($id);
177: 
178:         /* Execute the query. */
179:         try {
180:             $this->_db->delete($query, $values);
181:             $this->_db->commitDbTransaction();
182:         } catch (Horde_Db_Exception $e) {
183:             return false;
184:         }
185: 
186:         return true;
187:     }
188: 
189:     /**
190:      */
191:     public function gc($maxlifetime = 300)
192:     {
193:         /* Build the SQL query. */
194:         $query = sprintf('DELETE FROM %s WHERE session_lastmodified < ?',
195:                          $this->_params['table']);
196:         $values = array(time() - $maxlifetime);
197: 
198:         /* Execute the query. */
199:         try {
200:             $this->_db->delete($query, $values);
201:         } catch (Horde_Db_Exception $e) {
202:             return false;
203:         }
204: 
205:         return true;
206:     }
207: 
208:     /**
209:      */
210:     public function getSessionIDs()
211:     {
212:         $this->open();
213: 
214:         /* Build the SQL query. */
215:         $query = sprintf('SELECT session_id FROM %s' .
216:                          ' WHERE session_lastmodified >= ?',
217:                          $this->_params['table']);
218:         $values = array(time() - ini_get('session.gc_maxlifetime'));
219: 
220:         /* Execute the query. */
221:         try {
222:             return $this->_db->selectValues($query, $values);
223:         } catch (Horde_Db_Exception $e) {
224:             return array();
225:         }
226:     }
227: }
228: