Invalid HTTP request received when making request from NextJS front-end server proxy

[lukemasonIC]

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Example Code

from fastapi.middleware.cors import CORSMiddleware

app = FastAPI()

origins = ["*"]

app.add_middleware(
    CORSMiddleware,
    allow_origins=origins,
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

Description

I'm running a NextJS server proxy in my front-end application to make requests to a FastAPI back-end. I have set the CORS wildcard and read through the docs but still receive the invalid http request error. I imagine it has to do with CORS, but I still can't seem to get it working. Any help would be great, thank you!

Operating System

macOS

Operating System Details

No response

FastAPI Version

0.100.0

Pydantic Version

2.0.3

Python Version

Python 3.11.7

Additional Context

No response

[YuriiMotov]

Have you read about the limitation of wildcards in CORS origins? https://fastapi.tiangolo.com/tutorial/cors/#wildcards

But that will only allow certain types of communication, excluding everything that involves credentials: Cookies, Authorization headers like those used with Bearer Tokens, etc.

Have you tried to specify front-end origin explicitly?

[lukemasonIC]

Hi @YuriiMotov! I have tried specific origins as well and am not seeing any luck with that either

[YuriiMotov]

And what about the error? Can you see the status code or any other information about the error?
What do you see on back-end server console\log?