<?php
require '../vendor/autoload.php';
use Firebase\JWT\JWT;
use Firebase\JWT\Key;

include("jwtsecret.php");

if(!isset($_GET["token"])) die("GET token fehlt");
$token=$_GET["token"];

$payload = JWT::decode($token, new Key($secret, 'HS256'));

if($payload->exp < time()){
    die("Token abgelaufen");
}

print_r($payload);