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Example Code

# code snippet copied from the official documentation

from fastapi import Depends, FastAPI, Header, HTTPException


async def verify_token(x_token: str = Header()):
    if x_token != "fake-super-secret-token":
        raise HTTPException(status_code=400, detail="X-Token header invalid")


async def verify_key(x_key: str = Header()):
    if x_key != "fake-super-secret-key":
        raise HTTPException(status_code=400, detail="X-Key header invalid")
    return x_key


app = FastAPI(dependencies=[Depends(verify_token), Depends(verify_key)])


@app.get("/items/")
async def read_items():
    return [{"item": "Portal Gun"}, {"item": "Plumbus"}]


@app.get("/users/")
async def read_users():
    return [{"username": "Rick"}, {"username": "Morty"}]

Description

TL;DR: maybe related to #4906

I was following the documentation of Global Dependencies and the example in the documentation is not working as expected.

I am getting the 422 status code with the following response

{
    "detail": [
        {
            "loc": [
                "header",
                "x-token"
            ],
            "msg": "field required",
            "type": "value_error.missing"
        },
        {
            "loc": [
                "header",
                "x-key"
            ],
            "msg": "field required",
            "type": "value_error.missing"
        }
    ]
}

Adding a default parameter to the Header(...) solved the issue

async def verify_token(x_token: str = Header(default=None)):
    ...


async def verify_key(x_key: str = Header(default=None)):
    ...

Operating System

Linux

Operating System Details

No response

FastAPI Version

0.78.0

Python Version

3.8.10

Additional Context

No response