* 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 it all...

If you have an API that does a comparable amount of computations every time and you have a lot of clients, then the **CPU utilization** will probably *also be stable* (instead of constantly going up and down quickly).

### Examples of Replication Tools and Strategies

There can be several approaches to achieve this, and I'll tell you more about specific strategies in the next chapters, for example when talking about Docker and containers.

you will have a more or less well-defined, stable, and limited amount of memory consumed by each of those containers (more than one if they are replicated).

And then you can set those same memory limits and requirements in your configurations for your container management system (for example in **Kubernetes**). That way it will be able to **replicate the containers** in the **available machines** taking into account the amount of memory needed by them, and the amount available in the machines...

### Tested

* 100% <abbr title="The amount of code that is automatically tested">test coverage</abbr>.
* 100% <abbr title="Python type annotations, with this your editor and external tools can give you better support">type annotated</abbr> code base.

It would take the same amount of time to finish with or without turns (concurrency) and you would have done the same amount of work.

### ♾ "🔌-🔌"

⚖️ 🎏 🌌, 🙅‍♂ 💪 👫, 🗄 & ⚙️ 📟 👆 💪.

🙆 🛠️ 🏗 🙅 ⚙️ (⏮️ 🔗) 👈 👆 💪 ✍ "🔌-" 👆 🈸 2️⃣ ⏸ 📟 ⚙️ 🎏 📊 & ❕ ⚙️ 👆 *➡ 🛠️*.

### 💯

* 1️⃣0️⃣0️⃣ 💯 <abbr title="The amount of code that is automatically tested">💯 💰</abbr>.
* 1️⃣0️⃣0️⃣ 💯 <abbr title="Python type annotations, with this your editor and external tools can give you better support">🆎 ✍</abbr> 📟 🧢.
* ⚙️ 🏭 🈸.

## 💃 ⚒

```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.

# 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!}
```

8. Notice that this *path operation function* uses regular `def` instead of `async def`.

    As always, in FastAPI you can combine `def` and `async def` as needed.

    If you need a refresher about when to use which, check out the section _"In a hurry?"_ in the docs about [`async` and `await`](../async.md#in-a-hurry){.internal-link target=_blank}.

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

### Mount the sub-application

In your top-level application, `app`, mount the sub-application, `subapi`.

In this case, it will be mounted at the path `/subapi`:

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