```Python hl_lines="3  6-8"
{!../../../docs_src/sub_applications/tutorial001.py!}
```

### 子应用

接下来，创建子应用及其*路径操作*。

子应用只是另一个标准 FastAPI 应用，但这个应用是被**挂载**的应用：

```Python hl_lines="11  14-16"
{!../../../docs_src/sub_applications/tutorial001.py!}
```

### 挂载子应用

在顶层应用 `app` 中，挂载子应用 `subapi`。

本例的子应用挂载在 `/subapi` 路径下：

```Python hl_lines="11  19"
{!../../../docs_src/sub_applications/tutorial001.py!}
```

### 🔝-🎚 🈸

🥇, ✍ 👑, 🔝-🎚, **FastAPI** 🈸, & 🚮 *➡ 🛠️*:

```Python hl_lines="3  6-8"
{!../../../docs_src/sub_applications/tutorial001.py!}
```

### 🎧-🈸

⤴️, ✍ 👆 🎧-🈸, & 🚮 *➡ 🛠️*.

👉 🎧-🈸 ➕1️⃣ 🐩 FastAPI 🈸, ✋️ 👉 1️⃣ 👈 🔜 "🗻":

```Python hl_lines="11  14-16"
{!../../../docs_src/sub_applications/tutorial001.py!}
```

### 🗻 🎧-🈸

👆 🔝-🎚 🈸, `app`, 🗻 🎧-🈸, `subapi`.

client = TestClient(app)


async def overrider_dependency_simple(q: Optional[str] = None):
    return {"q": q, "skip": 5, "limit": 10}


async def overrider_sub_dependency(k: str):
    return {"k": k}


async def overrider_dependency_with_sub(msg: dict = Depends(overrider_sub_dependency)):
    return msg


def test_main_depends():
    response = client.get("/main-depends/")
    assert response.status_code == 422

        detail="Could not validate credentials",
        headers={"WWW-Authenticate": "Bearer"},
    )
    try:
        payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
        username: str = payload.get("sub")
        if username is None:
            raise credentials_exception
        token_data = TokenData(username=username)
    except JWTError:
        raise credentials_exception

So, to avoid ID collisions, when creating the JWT token for the user, you could prefix the value of the `sub` key, e.g. with `username:`. So, in this example, the value of `sub` could have been: `username:johndoe`.

The important thing to keep in mind is that the `sub` key should have a unique identifier across the entire application, and it should be a string.

## Check it

    Incluindo como manipular estado do lifespan que pode ser usado em outras áreas do seu código.

## Sub Aplicações

        headers={"WWW-Authenticate": authenticate_value},
    )
    try:
        payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
        username: str = payload.get("sub")
        if username is None:
            raise credentials_exception
        token_scopes = payload.get("scopes", [])
        token_data = TokenData(scopes=token_scopes, username=username)

# ✅ 🇨🇻 - 🏺, ✳, 🎏

👆 💪 🗻 🇨🇻 🈸 👆 👀 ⏮️ [🎧 🈸 - 🗻](sub-applications.md){.internal-link target=_blank}, [⛅ 🗳](behind-a-proxy.md){.internal-link target=_blank}.

👈, 👆 💪 ⚙️ `WSGIMiddleware` & ⚙️ ⚫️ 🎁 👆 🇨🇻 🈸, 🖼, 🏺, ✳, ♒️.

## ⚙️ `WSGIMiddleware`

👆 💪 🗄 `WSGIMiddleware`.

⤴️ 🎁 🇨🇻 (✅ 🏺) 📱 ⏮️ 🛠️.

& ⤴️ 🗻 👈 🔽 ➡.

```Python hl_lines="2-3  22"
{!../../../docs_src/wsgi/tutorial001.py!}
```

## ✅ ⚫️

## Unteranwendungen

### Dependências

O mesmo se aplica para as dependências. Se uma dependência tem as funções com padrão `def` ao invés de `async def`, ela é rodada no threadpool externo.

### Sub-dependências