Handling serialisation of response bodies

[Connorcee]

Hi!

I may be completely incorrect here, but I'm not quite sure how to handle this situation based on examples in the docs. I have a route that returns a Response. Inside this I have two pydantic classes as a union. I have attached a test I found from the powertools code that is essentially my scenario:

def test_openapi_union_response():
    app = APIGatewayRestResolver(enable_validation=True)

    class User(BaseModel):
        pass

    class Order(BaseModel):
        pass

    @app.get(
        "/",
        responses={
            200: {"description": "200 Response", "content": {"application/json": {"model": User}}},
            202: {"description": "202 Response", "content": {"application/json": {"model": Order}}},
        },
    )
    def handler() -> Response[Union[User, Order]]:
        if randbelow(2) > 0:
            return Response(status_code=200, body=User())
        else:
            return Response(status_code=202, body=Order())

    schema = app.get_openapi_schema()
    responses = schema.paths["/"].get.responses
    assert 200 in responses.keys()
    assert responses[200].description == "200 Response"
    assert responses[200].content["application/json"].schema_.ref == "#/components/schemas/User"

    assert 202 in responses.keys()
    assert responses[202].description == "202 Response"
    assert responses[202].content["application/json"].schema_.ref == "#/components/schemas/Order"

Ignoring the schema asserts, when I take this code, and run resolve on the app instance, I get back a payload which is a dictionary containing the type Order, rather than a serialised version of Order. This isn't something I can return from my lambda handler to API gateways so I was wondering what the correct way to do this is (if at all)?

[Connorcee]

Sovled by setting the content type to application/json