Bootstrap and route a request in Magento

When a request hits Magento's entry point in pub/index.php, PHP takes control and Magento begins its initialization process. Let's see how Magento bootstraps itself and determines which code handles the incoming request.

The bootstrap process

The pub/index.php file is surprisingly simple. It finds the application directory and creates a bootstrapper:

<?php
/**
 * Public alias for the application entry point
 *
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */

use Magento\Framework\App\Bootstrap;

try...