Dependency Injection to Middleware

Having a bear of a time figuring out how to inject dependencies into Middleware. My dependencies file looks like this:

return function (ContainerBuilder $containerBuilder) {
    $containerBuilder->addDefinitions([

        App::class => function (ContainerInterface $container) {
            AppFactory::setContainer($container);

            return AppFactory::create();
        },

        Auth::class => function (ContainerInterface $container) {
            return new Auth($container->get(MysqliDb::class));
        },

        . . . . . unrelated stuff . . . . .

        AuthMiddleware::class => function (ContainerInterface $container) {
            return new AuthMiddleware(
                $container->get(Auth::class)
            );
        },
    ]);
};

then my Middleware like so:

class AuthMiddleware implements MiddlewareInterface {

    /**
     * @var Auth
     */
    protected $auth;

    /**
     * @param Auth $auth
     */
    public function __construct(Auth $auth)
    {
        $this->auth = $auth;
    }

    public function process(Request $request, RequestHandler $handler): Response
    {
        // some stuff using auth...
        return $handler->handle($request);
    }

}

but when I add it to a route:

$app->get('/members', MembersAction::class)->add(AuthMiddleware::class);

I keep getting the error:

{
    "statusCode": 500,
    "error": {
        "type": "SERVER_ERROR",
        "description": "Callable AuthMiddleware does not exist"
    }
}

any clues where I’m going wrong? A kick in the right direction?

Is AuthMiddleware::class set as an import in your routes config?

Hey thanks for the comment. It was, but you’re on the right track, it wasn’t in my dependencies. I forgot to come back and update the topic.

Thanks.