SLIM PUT-Request CORS Header missing - php

Question

I've tried to set up a Angular App with SLIM Framework v4 Backend; Angular is running local, while Slim is on a Deploy Server. So CORS Setup is needed and I did like given in the documentation:
$app->options('/{routes:.+}', function ($request, $response, $args) {
return $response;
});
$app->add(function ($request, $handler) {
$response = $handler->handle($request);
return $response
->withHeader('Access-Control-Allow-Origin', '*')
->withHeader('Access-Control-Allow-Headers', 'X-Requested-With, Content-Type, Accept, Origin, Authorization')
->withHeader('Access-Control-Allow-Methods', 'GET, POST, PUT, DELETE, PATCH, OPTIONS');
});
On get Requests the Acces-Control-Allow-Origin Header is present; no problem, everything working as expected. On Put request (example):
$app->put('/event/{id}', function (Request $request, Response $response, $args) use ($app) {
$id = $args['id'];
$response
->withHeader('Access-Control-Allow-Origin', '*')
->withHeader('Access-Control-Allow-Headers', 'X-Requested-With, Content-Type, Accept, Origin, Authorization');
$response->getBody()->write('Test with $id');
return $response;
});
even with an additional add in the function, the header is not present on the response in the browser.
What am I doing wrong?

Answer 1

The request and response object is immutable. You can try this:
$app->put('/event/{id}', function (Request $request, Response $response, $args) {
$id = $args['id'];
$response = $response
->withHeader('Access-Control-Allow-Origin', '*')
->withHeader('Access-Control-Allow-Headers', 'X-Requested-With, Content-Type, Accept, Origin, Authorization');
$response->getBody()->write('Test with $id');
return $response;
}