Mini Mezzio

Make setting up a Mezzio application even quicker by using this package. This makes an assumption that you are happy to use:

• laminas/diactoros for the application's PSR-7 server request implementation
• You do not need to use the SapiStreamEmitter
• Your ServerRequest comes from $_SERVER

All you need to provide is:

• A container instance implementing ContainerInterface, for example laminas-servicemanager
• A router instance implementing RouterInterface, for example FastRoute

You would then pipe the RouteMiddleware, DispatchMiddleware, and any other middleware or request handlers that your application needs.

Basic Usage: Example Application using Mini Mezzio

First you must require Mini Mezzio, a container, and a router with Composer. In this example, we'll use Laminas ServiceManager and FastRoute.

$ composer require asgrim/mini-mezzio laminas/laminas-servicemanager mezzio/mezzio-fastroute

Then in public/index.php we can create our application:

<?php

declare(strict_types=1);

use Laminas\Diactoros\Response\TextResponse;
use Laminas\ServiceManager\ServiceManager;
use Asgrim\MiniMezzio\AppFactory;
use Mezzio\Router\FastRouteRouter;
use Mezzio\Router\Middleware\DispatchMiddleware;
use Mezzio\Router\Middleware\RouteMiddleware;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;
use Psr\Http\Server\RequestHandlerInterface;

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

$container = new ServiceManager();
$router = new FastRouteRouter();
$app = AppFactory::create($container, $router);
$app->pipe(new RouteMiddleware($router));
$app->pipe(new DispatchMiddleware());
$app->get('/hello-world', new class implements RequestHandlerInterface {
    public function handle(ServerRequestInterface $request): ResponseInterface
    {
        return new TextResponse('Hello world!');
    }
});
$app->run();

You can use the PHP built-in web server to check this works. Spin this up with:

$ php -S 0.0.0.0:8080 -t public public/index.php

Now if you visit http://localhost:8080/hello-world in your browser, you should see the text Hello world! displayed. Now you're ready to make middleware in minutes!

Use the container for pipeline and endpoints

It probably won't be long before you'll want to leverage the container to use dependency injection for your middleware handlers instead of putting them all in the public/index.php. Since Mezzio already can pull middleware from the container it is given, you can put your handler in a proper class:

<?php

declare(strict_types=1);

namespace MyApp\Handler;

use Laminas\Diactoros\Response\JsonResponse;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;
use Psr\Http\Server\RequestHandlerInterface;

final class HelloWorldHandler implements RequestHandlerInterface
{
     public function handle(ServerRequestInterface $request): ResponseInterface
     {
         return new JsonResponse(['message' => 'Hello world!'], 200);
     }
 }

You can update your public/index.php to pull things from the container:

<?php

declare(strict_types=1);

use Laminas\ServiceManager\AbstractFactory\ReflectionBasedAbstractFactory;
use Laminas\ServiceManager\ServiceManager;
use Asgrim\MiniMezzio\AppFactory;
use Mezzio\Router\FastRouteRouter;
use Mezzio\Router\Middleware\DispatchMiddleware;
use Mezzio\Router\Middleware\RouteMiddleware;
use Mezzio\Router\RouterInterface;

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

$container = new ServiceManager();
$container->addAbstractFactory(ReflectionBasedAbstractFactory::class);
$container->setFactory(RouterInterface::class, static function () {
    return new FastRouteRouter();
});
$app = AppFactory::create($container, $container->get(RouterInterface::class));
$app->pipe(RouteMiddleware::class);
$app->pipe(DispatchMiddleware::class);
$app->get('/hello-world', \MyApp\Handler\HelloWorldHandler::class);
$app->run();

We've updated several things here, using the power of Laminas Service Manager:

• Added the ReflectionBasedAbstractFactory - this allows DI autowiring based on reflection. This can autowire most things
• Added a factory for \Mezzio\Router\RouterInterface which returns the instance of Mezzio\Router\FastRouteRouter. The RouteMiddleware can then be autowired using the ReflectionBasedAbstractFactory
• RouteMiddleware and DispatchMiddleware are now referred to with just ::class rather than creating instances; since they're just strings, they are looked up in the container.
• The route GET /hello-world is mapped to \MyApp\Handler\HelloWorldHandler that we created above; again, since this is a string, the instance is fetched from the container.