CMS-CSE/public-cms/api/checkSession/index.php

<?php

session_start(); 

require_once "../../../env.inc.php"; 
require_once DOCUMENT_ROOT."/access.inc.php";
require_once DOCUMENT_ROOT."/conf.inc.php";
require_once DIR_PHP_LAYOUTS . "header.php";

if ($_SERVER['REQUEST_METHOD'] === 'GET') {
    echo apiSessionAuthenticator::checkSession();
}