Using bitexpert/pathfinder with willdurand/hateoas

When I began converting the unKonf API backend to make use of Adroit and Disco I wanted to give the willdurand/Hateoas a try to turn the API into a "real" HATEOAS REST web service. Since we use our Pathfinder component as a router it felt natural to use Pathfinder to generate the links for the relations between the different domain objects. Luckily the willdurand/hateoas is pretty flexible and allows to define custom Url Generators with a few lines of code:

$hateoas = \Hateoas\HateoasBuilder::create()
    ->setUrlGenerator(
        null,
        new \Hateoas\UrlGenerator\CallableUrlGenerator(
            function ($route, array $parameters, $abs) {
                // return url here
                return '';
            }
        )
    )
    ->build();

In case of Pathfinder the configuration looks like this:

$baseUrl = 'http://localhost/';
$router = new \bitExpert\Pathfinder\Psr7Router($baseUrl);
$router->setRoutes([
    \bitExpert\Pathfinder\Route::create()
        ->from('/days/[:dayId]/sessions')
        ->to('sessions')
        ->accepting('GET'),
]);

$hateoas = \Hateoas\HateoasBuilder::create($seralizer)
    ->setCacheDir($hateoasCache)
    ->addMetadataDir($hateoasCache)
    ->setUrlGenerator(
        null,
        new \Hateoas\UrlGenerator\CallableUrlGenerator(
            function ($route, array $parameters, $abs) use ($router) {
                return $router->generateUri($route, $parameters);
            }
        )
    )
    ->build();

The link relation configuration looks like this:

use Hateoas\Configuration\Annotation as Hateoas;

/**
 * @Hateoas\Relation(
 *      "sessions",
 *      href = @Hateoas\Route(
 *          "sessionsPerDayRoute",
 *          parameters = {
 *              "dayId" = "expr(object.getId())"
 *          }
 *      )
 * )
 */
class Day