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Should `quart.make_response` be typed as returning `Response`?
Steps to reproduce
With the following Quart app:
from quart import Response, make_response
from quart_trio import QuartTrio
app = QuartTrio(__name__)
@app.route("/")
async def hello_world() -> Response:
return await make_response("<p>Hello, World!</p>")
if __name__ == "__main__":
app.run()
mypy fails because make_response does not return a Response:
quart_app.py:9: error: Incompatible return value type (got "quart.wrappers.response.Response | werkzeug.wrappers.response.Response", expected "quart.wrappers.response.Response") [return-value]
Expected result
I would expect validation to pass. Indeed, the equivalent Flask app passes validation:
from flask import Flask, Response, make_response
app = Flask(__name__)
@app.route("/")
def hello_world() -> Response:
return make_response("<p>Hello, World!</p>")
Workarounds
- Use
return "<p>Hello, World!</p>"and mark the return type asstr. But figuring out the right type is tiring, is a maintenance burden and arguably introduces unnecessary variation in the code. - Use
return quart.Response("<p>Hello, World!</p>")but it quickly breaks for more complex types. I spent a lot of time trying to understand whyquart.Response({"headers": "foo", "params': "bar"})was returning "headersparams"! - Type the return as
quart.typing. ResponseTypes. This is what I'm doing right now in the urllib3 tests (https://github.com/urllib3/urllib3/pull/3193) but I would rather useResponse.
Environment
- Python version: 3.12.0
- Quart version: 0.19.3 (quart-trio 0.11.0)
I think the route should be typed as returning a ResponseReturnValue, does that work for you?
Yes, that works! However that's a lot to type. And it does not apply to after_request where Response is needed:
def apply_caching(response: Response) -> ResponseReturnValue:
...
But it works, so I'm happy to close this if you want to.