A custom middleware that delegates authentication to a specific adapter.

ConfigProvider.php

<?php

return [
    'dependencies' => [
        'factories' => [
            'BasicAuthMiddleware' => function (ContainerInterface $container): CustomAuthenticationMiddleware {
                $adapter = $container->get(BasicAuthAdapter::class);
                return new CustomAuthenticationMiddleware($adapter);
            },
            'OAuth2Middleware' => function (ContainerInterface $container): CustomAuthenticationMiddleware {
                $adapter = $container->get(OAuth2Adapter::class);
                return new CustomAuthenticationMiddleware($adapter);
            },
        ],
    ],
];

CustomAuthenticationMiddleware.php

<?php

final readonly class CustomAuthenticationMiddleware implements MiddlewareInterface
{
    public function __construct(
        private AuthenticationInterface $adapter
    ) {}

    public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
    {
        $user = $this->adapter->authenticate($request);
        if (! $user instanceof UserInterface) {
            return $this->adapter->unauthorizedResponse($request);
        }
        return $handler->handle($request->withAttribute(UserInterface::class, $user));
    }
}

routes.php

<?php

$app->get('/api/resource', ['BasicAuthMiddleware'], 'api.resource');
$app->get('/oauth2/resource', ['OAuth2Middleware'], 'oauth2.resource');