Application Life Cycle

You'll find the application life cycle in the public/index.php file:

require_once __DIR__.'/../vendor/autoload.php';

use Borsch\Application\ApplicationInterface;
use Psr\Container\ContainerInterface;
use Psr\Http\Message\ServerRequestInterface;

/** @var ContainerInterface $container */
$container = (require_once __DIR__.'/../config/container.php');

$app = $container->get(ApplicationInterface::class);

(require_once __DIR__.'/../config/pipeline.php')($app, $container);
(require_once __DIR__.'/../config/routes.php')($app, $container);

$request = $container->get(ServerRequestInterface::class);

$app->run($request);

Container

A Dependency Injection Container is used to define application dependencies (router, request handler, server request factory and even the Application instance itself), middlewares and related dependencies.

The application is loaded from the container so its dependencies are automatically resolved.
The pipeline and routes are then defined.
The PSR-15 Request Handler is then run to return a PSR-7 ResponseInterface to the client.

In the file ./config/container.php you can find the application dependencies. Usually you will need to add your own dependencies in the Pipeline and Handlers section, but you can add or update anything else.

Pipeline

The pipeline is the heart of your application and consist of a sequence of Middlewares.
Every request goes through the pipeline until a PSR-7 Response is return.

The default pipeline should be good as is and should not require much changes to comply to your need.
To ease your development, all Pipelines middlewares are located in your ./src/Middleware folder so feel free to change everything as you need.

The different steps that occurs in the pipeline :

1. Error handler middleware
2. Trailing slash middleware
3. Segregated path middleware
4. Routing middleware
5. Implicit HEAD middleware
6. Implicit OPTIONS middleware
7. Method Not Allowed middleware
8. Dispatched middleware
9. Not Found Handler middleware

The ./config/pipeline.php file is well documented, have a look at it if you need more information.

Routes

You can define your application's routes in the file ./config/routes.php.
Note that this skeleton uses a nikic/FastRoute implementation router, so you can use the FastRoute pattern to define your app routes.

$app->get('/', HomeHandler::class, 'home');
$app->get('/user[/{id:\d+}]', UserHandler::class, 'user');

By default, in a production environment, a cache file is generated in ./storage/smarty/routes.cache.php.
You can modify this in the ./config/container.php file, in the RouterInterface::class definition.

Response

At the end of the pipeline process, a PSR-7 ResponseInterface object is returned and used to send back the response to the client.

If no route was found, a 404 Not Found is returned.
If route was found but with the wrong HTTP Method, a 405 Method Not Allowed is returned (with an "Allow" header).
These responses can be modified to your need.