HTTP — Request Lifecycle

Unlike most of the PHP frameworks, the HTTP requests begin outside of the application in the application server

• RoadRunner.

Note
The Response makes its way in a backward direction.

#PSR

Spiral is based on a set of standards that make it compatible with other frameworks, routers, middleware, etc. You can read more about PSR standards used here:

• PSR-7: HTTP message interfaces
• PSR-15: HTTP Server Request Handlers
• PSR-17: HTTP Factories

#Flow Description

A user request comes to the RoadRunner application server. The server will pass it through a number of middleware layers, some of which are used to enable serve static files or implement domain-specific logic.

Once all of the middleware processing is complete, the net/http request will be converted into PSR-7 format and passed to the first available PHP worker.

The worker will handle this request using the spiral/http component and Spiral\Http\Http core. The core will pass the PSR-7 request object (Psr\Http\Message\ServerRequestInterface) through a set of PSR-15 compatible middleware.

Once all of the middleware processing is complete, the framework will create an IoC scope for the request object. Such an approach allows you to use PSR-7 request as a classic global object, while technically, it only exists during the user request.

The request is passed into the PSR-15 handler of your choice (by default spiral/router). The handler must generate a response which will be sent back to the user through all the middleware layers.

Note
Spiral Router provides an ability to associate custom middleware set with each route.

#Invoke HTTP Manually

It is possible to invoke http core within the application. It can be useful for testing purposes or if you want to run Spiral from inside other frameworks. Obtain the instance of Spiral\Http\Http to do that:

namespace App\Endpoint\Web;

use Nyholm\Psr7\Uri;
use Psr\Http\Message\ServerRequestInterface;
use Spiral\Http\Http;

class HomeController implements SingletonInterface
{
    public function __construct(
        private readonly Http $http
    ) {
    }

    public function index(ServerRequestInterface $request): string
    {
        $response = $this->http->handle(
            $request->withUri(new Uri('/home/other')) // modify Uri of current request
        );

        return (string) $response->getBody(); // "other"
    }

    public function other(): string
    {
        return 'other';
    }
}

Note
The IoC scopes can be nested, so all the functionality will work properly. However, be aware that not all extensions will allow nesting (you are not allowed to create nested sessions yet).

#Events

Note
To learn more about dispatching events, see the Events section in our documentation.