Ajax request without extending session?

Yes, you're going to need to extend the session, because you are right in that a request can extend the expiration.

So block your request:

Code:

<?php

defined('BASEPATH') OR exit('No direct script access allowed');

class MY_Session extends CI_Session {

    public function __construct(array $params = [])
    {
        $CI =& get_instance();

        if( $CI->input->get('session_checker') == 1 )
              return;

        parent::__construct($params);
    }

    // ------------------------------------------------------------------------
}

Then you're probably going to need to be using database sessions, so you can query for the expiration.

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