from typing import Literal from http import HTTPStatus from aws_lambda_powertools.event_handler.api_gateway import APIGatewayRestResolver from pydantic import BaseModel import pytest app = APIGatewayRestResolver(enable_validation=True) class Todo(BaseModel): title: str status: Literal["Pending", "Done"] @app.get("/non_empty_string") def return_non_empty_string() -> Todo: return "hello" @app.get("/non_conforming_dict") def return_non_conforming_dict() -> Todo: return {"title": "fix_response_validation"} def lambda_handler(event, context): return app.resolve(event, context) # --- Tests below --- @pytest.fixture() def event_factory(): def _factory(path: str): return { "httpMethod": "GET", "path": path, } yield _factory @pytest.mark.parametrize(  "path",  [  ("/non_empty_string"),  ("/non_conforming_dict"),  ],  ids=["non_empty_string", "non_conforming_dict"], ) def test_correct_serialization_failure(path, event_factory): """Tests to demonstrate cases when response serialization fails, as expected.""" event = event_factory(path) response = lambda_handler(event, None) assert response["statusCode"] == HTTPStatus.UNPROCESSABLE_ENTITY if __name__ == "__main__": pytest.main(["-v", __file__])