from fastapi import APIRouter, Depends, HTTPException

from ..dependencies import get_token_header

router = APIRouter(
    prefix="/items",
    tags=["items"],
    dependencies=[Depends(get_token_header)],
    responses={404: {"description": "Not found"}},
)


fake_items_db = {"plumbus": {"name": "Plumbus"}, "gun": {"name": "Portal Gun"}}


@router.get("/")
async def read_items():
    return fake_items_db

## Benutzerdefinierte Header

Beachten Sie, dass benutzerdefinierte proprietäre Header <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">mittels des Präfix 'X-'</a> hinzugefügt werden können.

Sie sehen die automatische API-Dokumentation für die Unteranwendung, welche nur deren eigene _Pfadoperationen_ anzeigt, alle unter dem korrekten Unterpfad-Präfix `/subapi`:

<img src="/img/tutorial/sub-applications/image02.png">

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

app = FastAPI(openapi_prefix="/api/v1")


@app.get("/app")
def read_main(request: Request):
    return {"message": "Hello World", "root_path": request.scope.get("root_path")}


client = TestClient(app)


def test_main():
    response = client.get("/app")
    assert response.status_code == 200

METHODS_WITH_BODY = {"GET", "HEAD", "POST", "PUT", "DELETE", "PATCH"}
REF_PREFIX = "#/components/schemas/"

from .routers import items, users

app = FastAPI(dependencies=[Depends(get_query_token)])


app.include_router(users.router)
app.include_router(items.router)
app.include_router(
    admin.router,
    prefix="/admin",
    tags=["admin"],
    dependencies=[Depends(get_token_header)],
    responses={418: {"description": "I'm a teapot"}},
)


@app.get("/")
async def root():

Da der Pfad jeder *Pfadoperation* mit `/` beginnen muss, wie in:

```Python hl_lines="1"
@router.get("/{item_id}")
async def read_item(item_id: str):
    ...
```

... darf das Präfix kein abschließendes `/` enthalten.

Das Präfix lautet in diesem Fall also `/items`.

Wir können auch eine Liste von `tags` und zusätzliche `responses` hinzufügen, die auf alle in diesem Router enthaltenen *Pfadoperationen* angewendet werden.

    if user_id is None:
        return {"item_id": item_id}
    else:
        return {"item_id": item_id, "user_id": user_id}


app.include_router(user_router, prefix="/users")
app.include_router(item_router, prefix="/items")

app.include_router(item_router, prefix="/users/{user_id}/items")


client = TestClient(app)


def test_get_users():
    """Check that /users returns expected data"""

from fastapi import APIRouter, Depends, HTTPException

from ..dependencies import get_token_header

router = APIRouter(
    prefix="/items",
    tags=["items"],
    dependencies=[Depends(get_token_header)],
    responses={404: {"description": "Not found"}},
)


fake_items_db = {"plumbus": {"name": "Plumbus"}, "gun": {"name": "Portal Gun"}}


@router.get("/")
async def read_items():
    return fake_items_db

## Custom Headers

Keep in mind that custom proprietary headers can be added <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">using the 'X-' prefix</a>.