Подобно тому, как вы можете [добавлять зависимости через параметр `dependencies` в *декораторах операций пути*](dependencies-in-path-operation-decorators.md){.internal-link target=_blank}, вы можете добавлять зависимости сразу ко всему `FastAPI` приложению.

В этом случае они будут применяться ко всем *операциям пути* в приложении:

//// tab | Python 3.9+

```Python hl_lines="16"
{!> ../../docs_src/dependencies/tutorial012_an_py39.py!}
```

////

### 👥 ⚒ ❌

👥, 🗿, ⚒ **❌**, 🌐 🕰. 🖥 🌖 *🕧* ✔️ **🐛** 🕵‍♂ 🎏 🥉. 👶

& 👥 👩‍💻 🚧 📉 📟 👥 🔎 👈 🐛 & 👥 🛠️ 🆕 ⚒ (🎲 ❎ 🆕 🐛 💁‍♂️ 👶).

### 🤪 ❌ 🔁 🍵

🕐❔ 🏗 🕸 🔗 ⏮️ FastAPI, 🚥 📤 ❌ 👆 📟, FastAPI 🔜 🛎 🔌 ⚫️ 👁 📨 👈 ⏲ ❌. 🛡

👩‍💻 🔜 🤚 **5️⃣0️⃣0️⃣ 🔗 💽 ❌** 👈 📨, ✋️ 🈸 🔜 😣 👷 ⏭ 📨 ↩️ 💥 🍕.

### 🦏 ❌ - 💥

👐, 📤 5️⃣📆 💼 🌐❔ 👥 ✍ 📟 👈 **💥 🎂 🈸** ⚒ Uvicorn & 🐍 💥. 👶

### Небольшие ошибки обрабатываются автоматически

Когда вы создаёте свои API на основе FastAPI и допускаете в коде ошибку, то FastAPI обычно остановит её распространение внутри одного запроса, при обработке которого она возникла. 🛡

# 🏃 💽 ❎ - Uvicorn

👑 👜 👆 💪 🏃 **FastAPI** 🈸 🛰 💽 🎰 🔫 💽 📋 💖 **Uvicorn**.

📤 3️⃣ 👑 🎛:

* <a href="https://www.uvicorn.org/" class="external-link" target="_blank">Uvicorn</a>: ↕ 🎭 🔫 💽.
* <a href="https://hypercorn.readthedocs.io/" class="external-link" target="_blank">Hypercorn</a>: 🔫 💽 🔗 ⏮️ 🇺🇸🔍/2️⃣ &amp; 🎻 👪 🎏 ⚒.
* <a href="https://github.com/django/daphne" class="external-link" target="_blank">👸</a>: 🔫 💽 🏗 ✳ 📻.

有些编辑器会检查代码中没使用过的函数参数，并显示错误提示。

在*路径操作装饰器*中使用 `dependencies` 参数，可以确保在执行依赖项的同时，避免编辑器显示错误提示。

使用路径装饰器依赖项还可以避免开发新人误会代码中包含无用的未使用参数。

///

/// info | "说明"

本例中，使用的是自定义响应头 `X-Key` 和 `X-Token`。

但实际开发中，尤其是在实现安全措施时，最好使用 FastAPI 内置的[安全工具](../security/index.md){.internal-link target=_blank}（详见下一章）。

///

## 依赖项错误和返回值

路径装饰器依赖项也可以使用普通的依赖项*函数*。

### 依赖项的需求项

路径装饰器依赖项可以声明请求的需求项（比如响应头）或其他子依赖项：

```Python hl_lines="6  11"

```

////

//// tab | 🐍 3️⃣.1️⃣0️⃣ & 🔛

```Python hl_lines="2"
{!> ../../docs_src/body_fields/tutorial001_py310.py!}
```

////

/// warning

👀 👈 `Field` 🗄 🔗 ⚪️➡️ `pydantic`, 🚫 ⚪️➡️ `fastapi` 🌐 🎂 (`Query`, `Path`, `Body`, ♒️).

///

## 📣 🏷 🔢

👆 💪 ⤴️ ⚙️ `Field` ⏮️ 🏷 🔢:

//// tab | 🐍 3️⃣.6️⃣ & 🔛

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

## Import `Field`

First, you have to import it:

{* ../../docs_src/body_fields/tutorial001_an_py310.py hl[4] *}


/// warning

Notice that `Field` is imported directly from `pydantic`, not from `fastapi` as are all the rest (`Query`, `Path`, `Body`, etc).

///

## Declare model attributes

You can then use `Field` with model attributes:

{* ../../docs_src/body_fields/tutorial001_an_py310.py hl[11:14] *}

import pytest
from dirty_equals import IsDict, IsOneOf
from fastapi.testclient import TestClient

from ...utils import needs_py310


@pytest.fixture(name="client")
def get_client():
    from docs_src.response_model.tutorial006_py310 import app

    client = TestClient(app)
    return client


@needs_py310
def test_read_item_name(client: TestClient):
    response = client.get("/items/bar/name")

import pytest
from dirty_equals import IsDict
from fastapi.testclient import TestClient

from ...utils import needs_py310


@pytest.fixture(name="client")
def get_client():
    from docs_src.extra_data_types.tutorial001_py310 import app

    client = TestClient(app)
    return client


@needs_py310
def test_extra_types(client: TestClient):
    item_id = "ff97dd87-a4a5-4a12-b412-cde99f33e00e"
    data = {

De forma semelhante a [adicionar dependências (`dependencies`) em *decoradores de operação de rota*](dependencies-in-path-operation-decorators.md){.internal-link target=_blank}, você pode adicioná-las à aplicação `FastAPI`.

Nesse caso, elas serão aplicadas a todas as *operações de rota* da aplicação:

//// tab | Python 3.9+

```Python hl_lines="16"
{!> ../../docs_src/dependencies/tutorial012_an_py39.py!}
```

////