Keep Coding

What I need is : Use a custom class to receive a HTTP Request and deal with it.
What I have so far:
$app->group('/user', function () use ($app) {
$app->post('/login', Auth::class . ':login');
}
And in my Auth Class:
use \Psr\Http\Message\ServerRequestInterface as Request;
use \Psr\Http\Message\ResponseInterface as Response;
// also tried: use Slim\Http\Request; use Slim\Http\Response;
class Auth {
protected $container;
public function __construct(&$c) {
$this->container = $c;
}
public function login(Request $request, Response $response, $args) {
// NEED TO GET GET/POST/PUT Params here
// When I Try to print $request, $response or $args, it returns empty
}
My code shows in the function login what I need : get the http params, and the request/response/args params. ( I want to implement many functions in one class, I mean, I don't want to use __invoke())
Another thing I don't understand is, if I do something like
return $response->withJson($somearraydata,200);
the variable $response actually works. Why?
Thanks for any help!

I think I have figured it out,
$args are never set,but request and response are.
and, to get params, I could do:
$request->getParsedBody()['attribute']
Hope this helps someone. :)