Session lib

[eluser]leonglass[/eluser]
I have a class that I have used before for managing sessions that makes use of phps session handling and using a db. I have been looking at CIs session class and have seen that the actual user data for the session is still stored in a cookie even when you set it to use the db. The class I have places the user data into a field in the db as name value pairs separated with semi-colons.

My questions are -
is the way CI does sessions better than the way I have been doing and if so why?
What do you all think of using my own class as a lib in CI does that make sense or not?

thanks

[eluser]Michael Wales[/eluser]
I'm not sure if it's better, but I have had no issues using the default CI method.

There are already some user created libraries out there to use native PHP sessions or to store all of the data in the database. If you create a CI library out of your class, I'm sure it will be a welcome addition to the community.

[eluser]leonglass[/eluser]
[quote author="walesmd" date="1193009524"]I'm not sure if it's better, but I have had no issues using the default CI method.

There are already some user created libraries out there to use native PHP sessions or to store all of the data in the database. If you create a CI library out of your class, I'm sure it will be a welcome addition to the community.[/quote]Thanks for replying. Where do you generally find user created libs?

[eluser]leonglass[/eluser]
OK here it is.
Session.php

Code:

<?php
/*

CREATE TABLE `<insert table name>` (
  `sid` char(32) NOT NULL,
  `expire` int(11) NOT NULL,
  `value` text NOT NULL,
  PRIMARY KEY  (`sid`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8;

*/

class Session
{
    var $CI;

    
/*
class constructor. sets the callback functions for using
a database with the session. Sets the session name and starts the
session.
*/    
    function __construct()
    {        
        $this->CI =& get_instance();
        session_set_save_handler(array(&$this, "open"),
                                        array(&$this, "close"),
                                array(&$this, "select"),
                              array(&$this, "write"),
                            array(&$this, "destroy"),
                                array(&$this, "gc"));
                                
    
      session_name($this->CI->config->item('sess_cookie_name'));
        session_start();
    }
    
    
/*
class destructor. Does nothing yet
*/    
    function __destruct()
    {
        /*session_write_close();*/
    }    
    
/*
* Don't do anything as I dont open a db
* The assumption is that the db has been autoloaded
*/
    function open($session_path, $session_name)
    {
        return 1;
    }
    
/*
* Doesn't actually do anything as I don't close the db
* allow the script ending to auto close db connections
*/
    function close()
    {
        return 1;
    }
    
/*
* Reads the session data from the database
*/
    function select($SID)
    {
        $where = array('sid' => $SID, 'expire >' => time());
       $this->CI->db->select('value');
       $query = $this->CI->db->get($this->CI->config->item('sess_table_name'));
      
       $row = $query->row();
       return $row->value;
    }
    
/*
* This function writes the session data to the database.
* If that SID already exists, then the existing data will be updated.
*/
    function write($SID, $value)
    {
    
            
       $expiration = time() + $this->CI->config->item('sess_expiration');      
       $query = "INSERT INTO " . $this->CI->config->item('sess_table_name') .
                                          " VALUES('$SID', '$expiration', '$value')";
            
      if( !$this->CI->db->simple_query($query))
      {
          $query = "UPDATE " . $this->CI->config->item('sess_table_name') .
                                                       " SET expire='" . $expiration .
                                     "', value='" . $value . "' WHERE sid='". $SID .
                                                       "' AND expire > '". time() . "'";
           $this->CI->db->query($query);
      }    
    }
    
    
/*
* Deletes all session information having input SID (only one row)
*/
    function destroy($SID)
    {
        $query = "DELETE FROM " . $this->CI->config->item('sess_table_name') . " WHERE sid = '$SID'";
       $this->CI->db->query($query);
    }
    
/*
* Deletes all sessions that have expired.
*/
    function gc($lifetime)
    {
        $query = "DELETE FROM " . $this->CI->config->item('sess_table_name') . " WHERE expire < " . time();
       $this->CI->db->query($query);
       return $query->num_rows();
    }

}//end class
?&gt;

It seems to be working after the minimal testing I have done on it. Place the php file in application/libraries and use the same configuration from application/config/config.php. Hope someone finds it usefull. Once this class is loaded you should be able to use $_SESSION['var_name'] as before and see the updates in your db. Let me know how you get on with this class.

[eluser]Michael Wales[/eluser]
You can find the user created libraries in the Wiki - the most recent version of CI (available in the SVN repo) has an updated Session library as well, supporting flashdata and ID regeneration.

You should definitely post your library as a new article in the Wiki.

[eluser]leonglass[/eluser]
Ok I will look at doing that. Thanks for telling where to find user created libs.