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

### زیر برنامه

سپس، زیر برنامه خود و path operations آن را ایجاد کنید.

این زیر برنامه فقط یکی دیگر از برنامه های استاندارد FastAPI است، اما این برنامه ای است که متصل می شود:

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

### اتصال زیر برنامه

```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`" 🎓.

🌐 🎏 🎛 🐕‍🦺.

First, create the main, top-level, **FastAPI** application, and its *path operations*:

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

### Sub-application

Then, create your sub-application, and its *path operations*.

This sub-application is just another standard FastAPI application, but this is the one that will be "mounted":

```Python hl_lines="11  14-16"

# 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

### 顶层应用

首先，创建主（顶层）**FastAPI** 应用及其*路径操作*：

```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：

🥇, ✍ 👑, 🔝-🎚, **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`.

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。

* **Starlette**:
    * Will have the next best performance, after Uvicorn. In fact, Starlette uses Uvicorn to run. So, it probably can only get "slower" than Uvicorn by having to execute more code.
    * But it provides you the tools to build simple web applications, with routing based on paths, etc.
    * If you are comparing Starlette, compare it against Sanic, Flask, Django, etc. Web frameworks (or microframeworks).

# Including WSGI - Flask, Django, others

You can mount WSGI applications as you saw with [Sub Applications - Mounts](sub-applications.md){.internal-link target=_blank}, [Behind a Proxy](behind-a-proxy.md){.internal-link target=_blank}.

For that, you can use the `WSGIMiddleware` and use it to wrap your WSGI application, for example, Flask, Django, etc.

## Using `WSGIMiddleware`

You need to import `WSGIMiddleware`.

# 包含 WSGI - Flask，Django，其它

您可以挂载多个 WSGI 应用，正如您在 [Sub Applications - Mounts](sub-applications.md){.internal-link target=_blank}, [Behind a Proxy](behind-a-proxy.md){.internal-link target=_blank} 中所看到的那样。

为此, 您可以使用 `WSGIMiddleware` 来包装你的 WSGI 应用，如：Flask，Django，等等。

## 使用 `WSGIMiddleware`

您需要导入 `WSGIMiddleware`。

然后使用该中间件包装 WSGI 应用（例如 Flask）。

之后将其挂载到某一个路径下。

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