"scopes": ["foo", "bar"],
        "data": [3, 4, 5],
    }
    app.dependency_overrides = {}


def test_override_security():
    app.dependency_overrides[get_user] = get_user_override
    response = client.get("/user")
    assert response.json() == {
        "user": "alice",
        "scopes": ["foo", "bar"],
        "data": [1, 2, 3],
    }

from fastapi import APIRouter, FastAPI
from fastapi.testclient import TestClient


def test_redirect_slashes_enabled():
    app = FastAPI()
    router = APIRouter()

    @router.get("/hello/")
    def hello_page() -> str:
        return "Hello, World!"

    app.include_router(router)

    client = TestClient(app)

    response = client.get("/hello/", follow_redirects=False)
    assert response.status_code == 200

        warnings.simplefilter("always")
        monkeypatch.delattr("multipart.multipart.parse_options_header", raising=False)
    with pytest.raises(RuntimeError, match=multipart_incorrect_install_error):
        app = FastAPI()

        @app.post("/")
        async def root(username: str = Form()):
            return username  # pragma: nocover


def test_incorrect_multipart_installed_file_upload(monkeypatch):

from .utils import get_body_model_name

app = FastAPI()

# =====================================================================================
# Without aliases


@app.post("/optional-bytes", operation_id="optional_bytes")
async def read_optional_bytes(p: Annotated[Optional[bytes], File()] = None):
    return {"file_size": len(p) if p else None}


@app.post("/optional-uploadfile", operation_id="optional_uploadfile")

from fastapi import FastAPI, Form
from fastapi.testclient import TestClient
from pydantic import BaseModel, Field

from .utils import get_body_model_name

app = FastAPI()

# =====================================================================================
# Without aliases


@app.post("/optional-str", operation_id="optional_str")
async def read_optional_str(p: Annotated[Optional[str], Form()] = None):
    return {"p": p}

`root_path` 用于处理这些特定情况。

在挂载子应用时，也可以在内部使用。

## 移除路径前缀的代理

本例中，移除路径前缀的代理是指在代码中声明路径 `/app`，然后在应用顶层添加代理，把 **FastAPI** 应用放在 `/api/v1` 路径下。

本例的原始路径 `/app` 实际上是在 `/api/v1/app` 提供服务。

哪怕所有代码都假设只有 `/app`。

代理只在把请求传送给 Uvicorn 之前才会**移除路径前缀**，让应用以为它是在 `/app` 提供服务，因此不必在代码中加入前缀 `/api/v1`。

但之后，在（前端）打开 API 文档时，代理会要求在 `/openapi.json`，而不是 `/api/v1/openapi.json` 中提取 OpenAPI 概图。

from .utils import get_body_model_name

app = FastAPI()

# =====================================================================================
# Without aliases


@app.post("/required-str", operation_id="required_str")
async def read_required_str(p: Annotated[str, Form()]):
    return {"p": p}


class FormModelRequiredStr(BaseModel):
    p: str

from .utils import get_body_model_name

app = FastAPI()

# =====================================================================================
# Without aliases


@app.post("/list-bytes", operation_id="list_bytes")
async def read_list_bytes(p: Annotated[list[bytes], File()]):
    return {"file_size": [len(file) for file in p]}


@app.post("/list-uploadfile", operation_id="list_uploadfile")

    raise CustomError()


def make_app(app=None, **kwargs):
    app = app or FastAPI(**kwargs)
    app.include_router(router)
    app.include_router(prefix_router, prefix="/prefix")
    app.include_router(native_prefix_route)
    return app


app = make_app(app)


def test_app():
    client = TestClient(app)
    with client.websocket_connect("/") as websocket:

import pytest
from fastapi import FastAPI, Query
from fastapi.testclient import TestClient
from pydantic import BaseModel, Field

app = FastAPI()

# =====================================================================================
# Without aliases


@app.get("/optional-list-str")
async def read_optional_list_str(
    p: Annotated[Optional[list[str]], Query()] = None,
):
    return {"p": p}