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

### *➡ 🛠️* ⏮️ `APIRouter`

& ⤴️ 👆 ⚙️ ⚫️ 📣 👆 *➡ 🛠️*.

⚙️ ⚫️ 🎏 🌌 👆 🔜 ⚙️ `FastAPI` 🎓:

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

👆 💪 💭 `APIRouter` "🐩 `FastAPI`" 🎓.

🌐 🎏 🎛 🐕‍🦺.

{!../../../docs_src/bigger_applications/app/routers/users.py!}
```

### *Pfadoperationen* mit `APIRouter`

Und dann verwenden Sie ihn, um Ihre *Pfadoperationen* zu deklarieren.

Verwenden Sie ihn auf die gleiche Weise wie die Klasse `FastAPI`:

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

# Bigger Applications - Multiple Files

If you are building an application or a web API, it's rarely the case that you can put everything on a single file.

**FastAPI** provides a convenience tool to structure your application while keeping all the flexibility.

!!! info
    If you come from Flask, this would be the equivalent of Flask's Blueprints.

## An example file structure

Let's say you have a file structure like this:

```
.
├── app

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。

* do we need a sort of bus for application data
* do we need a dictionary for our applications like Apple does. We could easily hook into this and this is the model we need to follow. Following the model of apple applications the dictionary is what the REST URI should attach to. Not creating custom logic in the resource code.
* how many of our REST services do not map directory to a method in the application interface?

- an example of adding js

### Multiple Applications

In the same server (or servers), there could be **multiple applications**, for example, other API programs or a database.

COPY ./requirements.txt /app/requirements.txt

RUN pip install --no-cache-dir --upgrade -r /app/requirements.txt

COPY ./app /app
```

### Bigger Applications

If you followed the section about creating [Bigger Applications with Multiple Files](../tutorial/bigger-applications.md){.internal-link target=_blank}, your `Dockerfile` might instead look like:

```Dockerfile hl_lines="7"
FROM tiangolo/uvicorn-gunicorn-fastapi:python3.9

And the `items_per_user` would keep its default value of `50`.

## Settings in another module

You could put those settings in another module file as you saw in [Bigger Applications - Multiple Files](../tutorial/bigger-applications.md){.internal-link target=_blank}.

For example, you could have a file `config.py` with:

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

```Python hl_lines="9"
{!../../../docs_src/behind_a_proxy/tutorial004.py!}
```

and then it won't include it in the OpenAPI schema.

## Mounting a sub-application

If you need to mount a sub-application (as described in [Sub Applications - Mounts](sub-applications.md){.internal-link target=_blank}) while also using a proxy with `root_path`, you can do it normally, as you would expect.

然后，`admin_email` 设置将为 `"******@****.***"`。

`app_name` 将为 `"ChimichangApp"`。

而 `items_per_user` 将保持其默认值为 `50`。

## 在另一个模块中设置

您可以将这些设置放在另一个模块文件中，就像您在[Bigger Applications - Multiple Files](../tutorial/bigger-applications.md){.internal-link target=_blank}中所见的那样。

例如，您可以创建一个名为 `config.py` 的文件，其中包含以下内容：

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

然后在一个名为 `main.py` 的文件中使用它：