Subversion-Projekte lars-tiefland.php_share

<?php

/*

 * This file is part of the symfony package.

 * (c) 2004-2006 Fabien Potencier <fabien.potencier@symfony-project.com>

 * (c) 2004-2006 Sean Kerr <sean@code-box.org>

 *

 * For the full copyright and license information, please view the LICENSE

 * file that was distributed with this source code.

 */

/**

 * Provides support for session storage using a MySQL brand database.

 *

 * <b>parameters:</b> see sfDatabaseSessionStorage

 *

 * @package    symfony

 * @subpackage storage

 * @author     Fabien Potencier <fabien.potencier@symfony-project.com>

 * @author     Sean Kerr <sean@code-box.org>

 * @author     Julien Garand <julien.garand@gmail.com>

 * @version    SVN: $Id: sfMySQLSessionStorage.class.php 24590 2009-11-30 18:28:13Z FabianLange $

 */

class sfMySQLSessionStorage extends sfDatabaseSessionStorage

{

  /**

   * Destroys a session.

   *

   * @param  string $id  A session ID

   *

   * @return bool true, if the session was destroyed, otherwise an exception is thrown

   *

   * @throws <b>sfDatabaseException</b> If the session cannot be destroyed.

   */

  public function sessionDestroy($id)

  {

    // get table/column

    $db_table  = $this->options['db_table'];

    $db_id_col = $this->options['db_id_col'];

    // cleanup the session id, just in case

    $id = $this->db_escape($id);

    // delete the record associated with this id

    $sql = "DELETE FROM $db_table WHERE $db_id_col = '$id'";

    if ($this->db_query($sql))

    {

      return true;

    }

    // failed to destroy session

    throw new sfDatabaseException(sprintf('%s cannot destroy session id "%s" (%s).', get_class($this), $id, $this->db_error()));

  }

  /**

   * Cleans up old sessions.

   *

   * @param  int $lifetime  The lifetime of a session

   *

   * @return bool true, if old sessions have been cleaned, otherwise an exception is thrown

   *

   * @throws <b>sfDatabaseException</b> If any old sessions cannot be cleaned

   */

  public function sessionGC($lifetime)

  {

    // get table/column

    $db_table    = $this->options['db_table'];

    $db_time_col = $this->options['db_time_col'];

    // delete the record older than the authorised session life time

    $lifetime = $this->db_escape($lifetime); // We never know...

    $sql = "DELETE FROM $db_table WHERE $db_time_col + $lifetime < UNIX_TIMESTAMP()";

    if (!$this->db_query($sql))

    {

      throw new sfDatabaseException(sprintf('%s cannot delete old sessions (%s).', get_class($this), $this->db_error()));

    }

    return true;

  }

  /**

   * Reads a session.

   *

   * @param  string $id  A session ID

   *

   * @return string      The session data if the session was read or created, otherwise an exception is thrown

   *

   * @throws <b>sfDatabaseException</b> If the session cannot be read

   */

  public function sessionRead($id)

  {

    // get table/column

    $db_table    = $this->options['db_table'];

    $db_data_col = $this->options['db_data_col'];

    $db_id_col   = $this->options['db_id_col'];

    $db_time_col = $this->options['db_time_col'];

    // cleanup the session id, just in case

    $id = $this->db_escape($id);

    // get the record associated with this id

    $sql = "SELECT $db_data_col FROM $db_table WHERE $db_id_col = '$id'";

    $result = $this->db_query($sql);

    if ($result != false && $this->db_num_rows($result) == 1)

    {

      // found the session

      $data = $this->db_fetch_row($result);

      return $data[0];

    }

    else

    {

      // session does not exist, create it

      $sql = "INSERT INTO $db_table ($db_id_col, $db_data_col, $db_time_col) VALUES ('$id', '', UNIX_TIMESTAMP())";

      if ($this->db_query($sql))

      {

        return '';

      }

      // can't create record

      throw new sfDatabaseException(sprintf('%s cannot create new record for id "%s" (%s).', get_class($this), $id, $this->db_error()));

    }

  }

  /**

   * Writes session data.

   *

   * @param  string $id    A session ID

   * @param  string $data  A serialized chunk of session data

   *

   * @return bool true, if the session was written, otherwise an exception is thrown

   *

   * @throws <b>sfDatabaseException</b> If the session data cannot be written

   */

  public function sessionWrite($id, $data)

  {

    // get table/column

    $db_table    = $this->options['db_table'];

    $db_data_col = $this->options['db_data_col'];

    $db_id_col   = $this->options['db_id_col'];

    $db_time_col = $this->options['db_time_col'];

    // cleanup the session id and data, just in case

    $id   = $this->db_escape($id);

    $data = $this->db_escape($data);

    // update the record associated with this id

    $sql = "UPDATE $db_table SET $db_data_col='$data', $db_time_col=UNIX_TIMESTAMP() WHERE $db_id_col='$id'";

    if ($this->db_query($sql))

    {

      return true;

    }

    // failed to write session data

    throw new sfDatabaseException(sprintf('%s cannot write session data for id "%s" (%s).', get_class($this), $id, $this->db_error()));

  }

  /**

   * Executes an SQL Query

   *

   * @param  string $query  The query to execute

   * @return mixed The result of the query

   */

  protected function db_query($query)

  {

    return @mysql_query($query, $this->db);

  }

  /**

   * Escapes a string before using it in a query statement

   *

   * @param  string $string  The string to escape

   * @return string The escaped string

   */

  protected function db_escape($string)

  {

    return mysql_real_escape_string($string, $this->db);

  }

  /**

   * Counts the rows in a query result

   *

   * @param  resource $result  Result of a query

   * @return int Number of rows

   */

  protected function db_num_rows($result)

  {

    return mysql_num_rows($result);

  }

  /**

   * Extracts a row from a query result set

   *

   * @param  resource $result  Result of a query

   * @return array Extracted row as an indexed array

   */

  protected function db_fetch_row($result)

  {

    return mysql_fetch_row($result);

  }

  /**

   * Returns the text of the error message from previous database operation

   *

   * @return string The error text from the last database function

   */

  protected function db_error()

  {

    return mysql_error($this->db);

  }

}