Response cookies not working

[cldtech]

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Example Code

@auth.post('/register/step1')
def register_step1(step1: RegStep1):
    content = {"status": "success"}
    response = JSONResponse(content=content)
    response.set_cookie(key="registration_id", value=uuid)
    return response

Description

According to the doc sending a response cookie if pretty simple exepct it's not working at all. I tried the exact example of the doc and it doesn't add the set cookie header.
I went in the code to see what's not happening but and i can't even find the set_cookie function in the JSONResponse object. What's happening with this feature? Thanks.

Operating System

Linux

Operating System Details

No response

FastAPI Version

0.103.1

Pydantic Version

2.3.0

Python Version

3.9.2

Additional Context

No response

[jgould22]

The set cookie function is here

How do you know the cookie is not set?

When I run the sample code in the docs I see it.

$ curl -I -X POST http://127.0.0.1:8000/cookie/
HTTP/1.1 200 OK
date: Fri, 27 Oct 2023 17:52:25 GMT
server: uvicorn
content-length: 52
content-type: application/json
set-cookie: fakesession=fake-cookie-session-value; Path=/; SameSite=lax

[cldtech]

Well i don't receive it on the client side looking from firefox developper tools (storage tab), or even from a simple api tester the response i receive is this;

[jgould22]

Yes, the swagger UI cannot access that header, so it wont appear in the list.

You can see the warning on the top of this page.

https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Set-Cookie

[cldtech]

Okay, but the cookie still doesn't end up in my front-end, i should see it in dev tools. The fetch request succeed but i don't receive the cookie.

[jgould22]

Using the example in the documentation the cookies appears in the response, and is sent with subsequent requests

What does your request look like in the dev tools?

[cldtech]

Okay, after purging my venv and reinstalling fastapi some how it works. I now see the set-cookie header sent by the server, but it still doesn't show in the storage tab and is not sent back to the server in the next request header. I guess it's not a fastapi problem anymore.