Automatically re-direct a user when session Times out or goes idle

Question

I want to have a timer going to run every 3 minutes on the page (javascript), to detect if a php session ($_SESSION) has timed out... and if so, redirect them automatically.

Answer 1

You could use a simple meta refresh:

Or you implement a timeout with PHP:

session_start();
if (isset($_SESSION['LAST_REQUEST_TIME'])) {
    if (time() - $_SESSION['LAST_REQUEST_TIME'] > 180) {
        // session timed out, last request is longer than 3 minutes ago
        $_SESSION = array();
        session_destroy();
    }
}
$_SESSION['LAST_REQUEST_TIME'] = time();

Then you don’t need to check every 3 minutes if the session is still valid.