How does it work in Slim Framework?

Slim Framework - Interview Questions

First, you need a web server like Nginx or Apache. You should configure your web server so that it sends all appropriate requests to one “front-controller” PHP file. You instantiate and run your Slim app in this PHP file.

A Slim app contains routes that respond to specific HTTP requests. Each route invokes a callback and returns an HTTP response. To get started, you first instantiate and configure the Slim application. Next, you define your application routes. Finally, you run the Slim application. It’s that easy. Here’s an example application :

<?php
use Psr\Http\Message\ResponseInterface as Response;
use Psr\Http\Message\ServerRequestInterface as Request;
use Slim\Factory\AppFactory;

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

/**
 * Instantiate App
 *
 * In order for the factory to work you need to ensure you have installed
 * a supported PSR-7 implementation of your choice e.g.: Slim PSR-7 and a supported
 * ServerRequest creator (included with Slim PSR-7)
 */
$app = AppFactory::create();

/**
  * The routing middleware should be added earlier than the ErrorMiddleware
  * Otherwise exceptions thrown from it will not be handled by the middleware
  */
$app->addRoutingMiddleware();

/**
 * Add Error Middleware
 *
 * @param bool                  $displayErrorDetails -> Should be set to false in production
 * @param bool                  $logErrors -> Parameter is passed to the default ErrorHandler
 * @param bool                  $logErrorDetails -> Display error details in error log
 * @param LoggerInterface|null  $logger -> Optional PSR-3 Logger  
 *
 * Note: This middleware should be added last. It will not handle any exceptions/errors
 * for middleware added after it.
 */
$errorMiddleware = $app->addErrorMiddleware(true, true, true);

// Define app routes
$app->get('/hello/{name}', function (Request $request, Response $response, $args) {
    $name = $args['name'];
    $response->getBody()->write("Hello, $name");
    return $response;
});

// Run app
$app->run();