Check server-side response (session validity/isset)

Tronik

I saw another thread about this but it had no answer.

Im using php sessions server-side to grant / deny users access to certain fields.
Problem occurs when the user has been inactive for some time (24mins i think session lifetime), come back to do a table search which will result in a "invalid json response" due to the session variables not set in server-side script.

On other pages I do a header location redirect to login page, and I would like to do the same in this case.

I was thinking I could check server side for active session and if not then return a 0 / false or whatever, return that to client and if so do a window.location redirect.
But how can I check this in client side before datables tries to render the table?

rf1234

But how can I check this in client side before datables tries to render the table?

You could make a synchronous ajax call to check - or a promise.

I found this in my code somewhere ...

$.ajax({
    type: "POST",
    url: 'actions.php?action=checkValidLogin',
    async: false,
    data: {
           ....
    },
    dataType: "json",
    success: function(data) {
        if (data.validLogin) {
            loginSettings(data);
        } else {
            notLoggedInSettings();
        }
    }
});

Tronik

I could do that, but then I need to execute that with every search/edit?
Just seems a bit unnecessary instead of checking valid sessions server side which is done anyway, and send back a false response

allan

Have the server return valid JSON such as:

{
  "data" : [],
  "sessionExpired": true
}

And listen for xhr which will check for the sessionExpired and perform whatever action you need (reload to a login page for example).

Allan

Tronik

Yes, I found another thread dealing with the same issue which was solved with xhr event.

This is my solution

in PHP

session_start();

if (!isset($_SESSION['user']))
{
    $data['code'] = 401;
    $data['data'] = [];
    $data['message'] = 'Session expired';
    echo json_encode($data);
    die();
}

And on client

$("#table").on('xhr.dt', function ( e, settings, json, xhr ) {
    if (json.code === 401) 
    {           
        location.href = '../login/'
    }
    else
        console.log('valid session')        
    });