Storing PHP Sessions in a Database - Opening and closing the session (
Page 4 of 8 )
On the previous page, when we called session_set_save_handler() to override the session handling functions, the first two arguments passed were for the open and close logic. Let's add these methods to our new class, then take a closer look.
function open( $save_path, $session_name ) {
global $sess_save_path;
$sess_save_path = $save_path;
// Don't need to do anything. Just return TRUE.
return true;
}
function close() {
return true;
}
The above code should be added inside the SessionManager class we started on the previous page.
Taking a close look, you will see that, for the most part, we didn't do anything in the open and close methods. That would be because we will be writing our information to a database. In this lesson, I am assuming that the application you are adding this to ALREADY has an open database connection to your database. If this is the case, then the above code is good as it is. If not, then the open function would need to include code for creating your database connection, and the close would close said connection.
If we were writing a new file-handling session manager, the open function would handle opening the file descriptor. The close function would then close said file descriptor, to prevent data from being lost.
So far, so good. But before we get to the point where we are actually writing the session information into the database, we need some place to put it. In your application database, you will need to create a "sessions" table to store the session information. Here's the one I defined, in MySQL create format:
CREATE TABLE `sessions` (
`session_id` varchar(100) NOT NULL default '',
`session_data` text NOT NULL,
`expires` int(11) NOT NULL default '0',
PRIMARY KEY (`session_id`)
) TYPE=MyISAM;
I would definitely suggest adding this table to your application's database. Not only does it keep it together with everything else, but it also makes it possible to share the same database connections for your sessions and your application itself.
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