<?php

namespace oopapi;

require_once './Invokable.php';
require_once './RequestHandler.php';
require_once './Invokation.php';

$handler = new Invokation();
$handler();
<?php

require_once './Invokable.php';
require_once './NonInvokableException.php';
require_once './RequestHandler.php';
require_once './Invokation.php';
require_once './Authentication.php';
require_once './Authorization.php';
Remove namespace, require NonInvokableException.php, Authentication.php, Authorization.php
Remove namespace, require NonInvokableException.php, Authentication.php, Authorization.php