全局依赖项

对于某些类型的应用程序，您可能希望向整个应用程序添加依赖项。

与您可以在路径操作装饰器中添加 dependencies 的方式类似，您可以将它们添加到 FastAPI 应用程序中。

在这种情况下，它们将应用于应用程序中的所有路径操作：

Python 3.9+

from fastapi import Depends, FastAPI, Header, HTTPException
from typing_extensions import Annotated


async def verify_token(x_token: Annotated[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: Annotated[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"}]

🤓 Other versions and variants

Python 3.8+Python 3.8+ - non-Annotated

from fastapi import Depends, FastAPI, Header, HTTPException
from typing_extensions import Annotated


async def verify_token(x_token: Annotated[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: Annotated[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"}]

Tip

Prefer to use the Annotated version if possible.

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"}]

关于在路径操作装饰器中添加 dependencies 的所有想法仍然适用，但在这种情况下，将应用于应用程序中的所有路径操作。

针对路径操作组的依赖项

稍后，在阅读如何构建更大的应用程序（更大的应用程序 - 多文件），可能涉及多个文件时，您将学习如何为一组路径操作声明单个 dependencies 参数。