HTTP Responders

HTTP Responders offer a flexible way to handle incoming HTTP requests. They are asynchronous and provide low-level access to HTTP headers, request content, cookies, connection management, and more.

This framework relies on HTTP Responders for constructing internal features, such as GraphQL integration.

Usage

Writing Responders

HTTP Responder should be a readonly class that serves a single purpose (responds only to one specific HTTP route).

Responders must implement the respond method that sends the response back to the HTTP client or forwards the request to a different responder.

You can generate a new responder class manually, or you can use the generate:http-responder command:

shell
$ php ./bin/resonance.php generate:http-responder Name

Responding to HTTP Requests

To respond to requests you should use Swoole's Response object:

php
<?php

namespace App\HttpResponder;

use App\HttpRouteSymbol;
use Distantmagic\Resonance\Attribute\RespondsToHttp;
use Distantmagic\Resonance\Attribute\Singleton;
use Distantmagic\Resonance\HttpResponderInterface;
use Distantmagic\Resonance\RequestMethod;
use Distantmagic\Resonance\SingletonCollection;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;

#[RespondsToHttp(
    method: RequestMethod::GET,
    pattern: '/',
    routeSymbol: HttpRouteSymbol::Homepage,
)]
#[Singleton(collection: SingletonCollection::HttpResponder)]
final readonly class Homepage implements HttpResponderInterface
{
    public function respond(ServerRequestInterface $request, ResponseInterface $response): ResponseInterface
    {
        return $response->withBody($this->createStream('Hello, world!'));
    }
}

Forwarding Requests to Other Responders

HTTP Responders can forward requests to other responders by returning another responder from the respond method.

For example:

php
<?php

use Distantmagic\Resonance\HttpResponderInterface;
use Distantmagic\Resonance\HttpResponder\Redirect;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;

class MyResponder implements HttpResponderInterface
{
    // (...)

    public function respond(ServerRequestInterface $request, ResponseInterface $response): HttpResponderInterface
    {
        return new Redirect('/blog');
    }
}

You can even use anonymous classes:

php
<?php

use Distantmagic\Resonance\HttpResponderInterface;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;

class MyResponder implements HttpResponderInterface
{
    public function respond(Request $request, Response $response): ?HttpResponderInterface
    {
        return new class implements HttpResponderInterface {
            public function respond (ServerRequestInterface $request, ResponseInterface $response): ResponseInterface {
                return $response->withBody($this->createStream('Hello!'));
            }
        };
    }
}

Function Responders

You can simplify responders even more by using function responders.

php
<?php

namespace App\HttpResponder;

use Distantmagic\Resonance\Attribute\RespondsToHttp;
use Distantmagic\Resonance\RequestMethod;
use Distantmagic\Resonance\TwigTemplate;

#[RespondsToHttp(
    method: RequestMethod::GET,
    pattern: '/blog',
)]
function Blog(): TwigTemplate
{
    return new TwigTemplate('turbo/blog.twig');
}

Built-In Responders

All of those responders use the Distantmagic\Resonance\HttpResponder namespace. For example you can use: Distantmagic\Resonance\HttpResponder\Error\PageNotFound.