[Bug]: Return types not generated

[klkvsk]

Version

5.9.2

Description

If a controller has a DTO return type, it is ignored. Neither native return type nor php-doc @return type are added to the schema.

    #[Route('/api/test', name: 'api_test', methods: [ 'GET' ])]
    public function index(): NameDto
    {
        return new NameDto();
    }

class NameDto
{
    public string $first = "John";
    public string $last = "Doe";
}

JSON OpenApi

JSON OpenApi

{
    "openapi": "3.0.0",
    "info": {
        "title": "My App",
        "description": "This is an awesome app!",
        "version": "1.0.0"
    },
    "paths": {
        "/api/test": {
            "get": {
                "operationId": "get_api_test",
                "responses": {
                    "default": {
                        "description": ""
                    }
                }
            }
        }
    }
}

Additional context

This is not a question of adding OA\Response attribute. While this is always an option, a leaner approach should be to get the responses described automatically, same as QueryParameters and RequestPayloads controller arguments.

[DjordyKoert]

As far as I know, Symfony doesn't automatically transform a DTO (or any class) returned from a method to a response which is why this isn't a supported feature currently.

I know that a PR is currently open to make this possible in Symfony itself symfony/symfony#49518

#2210

[klkvsk]

@DjordyKoert yes you are right, it await instance of Response to be returned, but a simple listener on 'kernel.view' can serialize Dto to JsonResponse.

JsonResponse is not a templated type though. So in order to keep the returned type info, it should work this way.