routers.md

Ulrack Web - Routers

Routers are used to determine which endpoint should be invoked for a request. They are described by the RouterInterface.

Routers have two required methods. accepts is to check whether the route would be able to resolve the request. The __invoke method is called when the router is chosen to determine the request. A router which would accept every request and resolve to the same endpoint would be:

<?php

namespace MyProject\MyPackage\Component\Router;

use Ulrack\Web\Common\Endpoint\InputInterface;
use Ulrack\Web\Common\Endpoint\OutputInterface;
use Ulrack\Web\Common\Router\RouterInterface

class MyRouter implements RouterInterface
{
    /**
     * Determines whether the router accepts the request.
     *
     * @param InputInterface $input
     * @param OutputInterface $output
     *
     * @return bool
     */
    public function accepts(
        InputInterface $input,
        OutputInterface $output
    ): bool {
        return true;
    }

    /**
     * Resolves the request to an endpoint, executes it and renders the response.
     *
     * @param InputInterface $input
     * @param OutputInterface $output
     *
     * @return void
     */
    public function __invoke(
        InputInterface $input,
        OutputInterface $output
    ): void {
        $input->setParameter('endpoint', 'services.my-endpoint');
    }
}

Endpoints must be set on the input by calling

$input->setParameter('endpoint', 'services.my-endpoint');

Where 'services.my-endpoint' should be replaced with a service reference that resolves to a service implementing the EndpointInterface. Additional parameters can also be set in the $input and can be used as {@template.*} references for the service creation.

This package supplies a few basic routers:

• BaseRouter This router should be used as a root router, because it handles all output related tasks.
• MiddlewareRouter This router can be used to implement middleware for another router. It will perform the checks on the middleware during the __invoke or accepts method invocation. When those checks fail in __invoke a HttpException will be thrown, resulting in a standard error.
• RouterAggregate This router can be used to pass multiple routers in, which will be iterated over and checked. It is recommended to pass an instance of this router to the BaseRouter to allow multiple other routers to handle requests.

Further reading

Back to usage index

Request codecs

Error

Endpoint

Middleware