```Python hl_lines="18-26"
{!../../../docs_src/custom_request_and_route/tutorial001.py!}
```

!!! note "技术细节"

    `Request` 的 `request.scope` 属性是包含关联请求元数据的字典。

    `Request` 的 `request.receive` 方法是**接收**请求体的函数。

    `scope` 字典与 `receive` 函数都是 ASGI 规范的内容。

    `scope` 与 `receive` 也是创建新的 `Request` 实例所需的。

    `Request` 的更多内容详见 <a href="https://www.starlette.io/requests/" class="external-link" target="_blank">Starlette 官档 - 请求</a>。

These are the people that:

* [Help others with questions in GitHub](help-fastapi.md#help-others-with-questions-in-github){.internal-link target=_blank}.
* [Create Pull Requests](help-fastapi.md#create-a-pull-request){.internal-link target=_blank}.
* Review Pull Requests, [especially important for translations](contributing.md#translations){.internal-link target=_blank}.

A round of applause to them. 👏 🙇

## FastAPI Experts

A "middleware" is a function that works with every **request** before it is processed by any specific *path operation*. And also with every **response** before returning it.

* It takes each **request** that comes to your application.
* It can then do something to that **request** or run any needed code.
* Then it passes the **request** to be processed by the rest of the application (by some *path operation*).

Eine „Middleware“ ist eine Funktion, die mit jedem **Request** arbeitet, bevor er von einer bestimmten *Pfadoperation* verarbeitet wird. Und auch mit jeder **Response**, bevor sie zurückgegeben wird.

* Sie nimmt jeden **Request** entgegen, der an Ihre Anwendung gesendet wird.
* Sie kann dann etwas mit diesem **Request** tun oder beliebigen Code ausführen.

    ```

Notice that the *path operations* define the models they use for request payload and response payload, using the models `Item` and `ResponseMessage`.

### API Docs

If you go to the API docs, you will see that it has the **schemas** for the data to be sent in requests and received in responses:

<img src="/img/tutorial/generate-clients/image01.png">

# Using Dataclasses

FastAPI is built on top of **Pydantic**, and I have been showing you how to use Pydantic models to declare requests and responses.

But FastAPI also supports using <a href="https://docs.python.org/3/library/dataclasses.html" class="external-link" target="_blank">`dataclasses`</a> the same way:

```Python hl_lines="1  7-12  19-20"
{!../../../docs_src/dataclasses/tutorial001.py!}
```

from .param_functions import Header as Header
from .param_functions import Path as Path
from .param_functions import Query as Query
from .param_functions import Security as Security
from .requests import Request as Request
from .responses import Response as Response
from .routing import APIRouter as APIRouter
from .websockets import WebSocket as WebSocket

!!! note "技術詳細"
    `from starlette.requests import Request` を使用することもできます。

    **FastAPI**は、開発者の便利のためにこれを提供していますが、Starletteから直接きています。

### `response` の前後

*path operation* が `request` を受け取る前に、 `request` とともに実行されるコードを追加できます。

また `response` が生成された後、それを返す前にも追加できます。

例えば、リクエストの処理とレスポンスの生成にかかった秒数を含むカスタムヘッダー `X-Process-Time` を追加できます:

### HTTPS Request

Now that the client and server (specifically the browser and the TLS Termination Proxy) have an **encrypted TCP connection**, they can start the **HTTP communication**.

So, the client sends an **HTTPS request**. This is just an HTTP request through an encrypted TLS connection.

<img src="/img/deployment/https/https04.svg">

### Decrypt the Request

* <a href="https://github.com/JoshData/python-email-validator" target="_blank"><code>email_validator</code></a> - per la validazione di email.

Usate da Starlette:

* <a href="http://docs.python-requests.org" target="_blank"><code>requests</code></a> - Richiesto se vuoi usare il `TestClient`.
* <a href="https://github.com/Tinche/aiofiles" target="_blank"><code>aiofiles</code></a> - Richiesto se vuoi usare `FileResponse` o `StaticFiles`.