```Python hl_lines="1  3" title="app/routers/users.py"
{!../../../docs_src/bigger_applications/app/routers/users.py!}
```

### *Path operations* with `APIRouter`

And then you use it to declare your *path operations*.

Use it the same way you would use the `FastAPI` class:

```Python hl_lines="6  11  16" title="app/routers/users.py"
{!../../../docs_src/bigger_applications/app/routers/users.py!}
```

你可以导入它并通过与 `FastAPI` 类相同的方式创建一个「实例」：

```Python hl_lines="1  3" title="app/routers/users.py"
{!../../../docs_src/bigger_applications/app/routers/users.py!}
```

### 使用 `APIRouter` 的*路径操作*

然后你可以使用它来声明*路径操作*。

使用方式与 `FastAPI` 类相同：

```Python hl_lines="6  11  16" title="app/routers/users.py"
{!../../../docs_src/bigger_applications/app/routers/users.py!}
```

你可以将 `APIRouter` 视为一个「迷你 `FastAPI`」类。

所有相同的选项都得到支持。

And your **FastAPI** application might also be composed of several files/modules, etc.

### **FastAPI** app file

Let's say you have a file structure as described in [Bigger Applications](bigger-applications.md){.internal-link target=_blank}:

```
.
├── app
│   ├── __init__.py
│   └── main.py
```

In the file `main.py` you have your **FastAPI** app:


```Python

    * So, by using FastAPI you are saving development time, bugs, lines of code, and you would probably get the same performance (or better) you would if you didn't use it (as you would have to implement...

    ```Python hl_lines="9  14"
    {!> ../../../docs_src/dependencies/tutorial006.py!}
    ```

## *경로 작동* 모음에 대한 의존성

나중에 여러 파일을 가지고 있을 수 있는 더 큰 애플리케이션을 구조화하는 법([더 큰 애플리케이션 - 여러 파일들](../../tutorial/bigger-applications.md){.internal-link target=_blank})을 읽을 때, *경로 작동* 모음에 대한 단일 `dependencies` 매개변수를 선언하는 법에 대해서 배우게 될 것입니다.

## 전역 의존성

## Beispiel

Betrachten wir als einfaches Beispiel eine Dateistruktur ähnlich der in [Größere Anwendungen](../tutorial/bigger-applications.md){.internal-link target=_blank} und [Testen](../tutorial/testing.md){.internal-link target=_blank}:

```
.
├── app
│   ├── __init__.py
│   ├── main.py
│   └── test_main.py
```

& ⤴️ `admin_email` ⚒ 🔜 ⚒ `"******@****.***"`.

`app_name` 🔜 `"ChimichangApp"`.

& `items_per_user` 🔜 🚧 🚮 🔢 💲 `50`.

## ⚒ ➕1️⃣ 🕹

👆 💪 🚮 👈 ⚒ ➕1️⃣ 🕹 📁 👆 👀 [🦏 🈸 - 💗 📁](../tutorial/bigger-applications.md){.internal-link target=_blank}.

🖼, 👆 💪 ✔️ 📁 `config.py` ⏮️:

```Python
{!../../../docs_src/settings/app01/config.py!}
```

& ⤴️ ⚙️ ⚫️ 📁 `main.py`:

The response object will also have autocompletion:

<img src="/img/tutorial/generate-clients/image05.png">

## FastAPI App with Tags

In many cases your FastAPI app will be bigger, and you will probably use tags to separate different groups of *path operations*.

For example, you could have a section for **items** and another section for **users**, and they could be separated by tags:

    assertThat(Adapters.INTEGER_AS_LONG.fromDer(bytes)).isEqualTo(Long.MIN_VALUE)
    assertThat(Adapters.INTEGER_AS_LONG.toDer(Long.MIN_VALUE)).isEqualTo(bytes)
  }

  @Test fun `bigger than max long`() {
    val bytes = "0209008000000000000001".decodeHex()
    val bigInteger = BigInteger("9223372036854775809")
    assertThat(Adapters.INTEGER_AS_BIG_INTEGER.fromDer(bytes)).isEqualTo(bigInteger)

The client will get a **500 Internal Server Error** for that request, but the application will continue working for the next requests instead of just crashing completely.

### Bigger Errors - Crashes

Nevertheless, there might be cases where we write some code that **crashes the entire application** making Uvicorn and Python crash. 💥