session timeout on page with ajax auto-refresh

Question

Good day folks - be gentle - I'm a first time poster.

I have a page on a php-based web site that uses an AJAX-based call to update a DIV tag with a table of data every 5 or 10 seconds. The security folks where I work want me to make sure users get logged out after 15 minutes of inactivity. To that end I put in

<script type="text/javascript">
window.setTimeout("location=('/mysite/session_timeout.php');",900000);
</script>

The problem is, of course, that the AJAX refresh of the table is 'resetting' the timeout counter ... So my question is basically "Is there a client-side way to either mitigate the ajax call resetting the clock so to speak, or do I need to address this with php's _SESSION array and hide values in there, or does someone have something better than that?"

Thanks for any help you all can provide.

Answer 1

You can Store the start time of that page and update you table data without reloading the page. and check for the start time and destroy session accordingly.

Answer 2

You can try something like this

$_SESSION['activity'] = time();

    function check_if_logged_in() {
        if(time() - $_SESSION['activity'] > 900) { 
            // Do redirect or take other action here
        }
    }

Or you can use this jQuery plugin.