---

## FastAPI 설치

첫 번째 단계는 FastAPI를 설치하는 것입니다.

자습시에는 모든 선택적인 의존성 및 기능을 함께 설치하는 것을 추천합니다:

<div class="termy">

```console
$ pip install "fastapi[all]"

---> 100%
```

</div>

...이는 코드를 실행하는 서버로 사용할 수 있는 `uvicorn` 또한 포함하고 있습니다.

!!! note "참고"
    부분적으로 설치할 수도 있습니다.

    애플리케이션을 운영 환경에 배포하려는 경우 다음과 같이 합니다:

    ```

The same way, there are many compatible tools. Including code generation tools for many languages.

## Pydantic

All the data validation is performed under the hood by <a href="https://docs.pydantic.dev/" class="external-link" target="_blank">Pydantic</a>, so you get all the benefits from it. And you know you are in good hands.

You can use the same type declarations with `str`, `float`, `bool` and many other complex data types.

    バックグラウンドタスク (後述) がある場合は、それらは全てのミドルウェアの *後に* 実行されます。

## ミドルウェアの作成

ミドルウェアを作成するには、関数の上部でデコレータ `@app.middleware("http")` を使用します。

ミドルウェア関数は以下を受け取ります:

* `request`。
* パラメータとして `request` を受け取る関数 `call_next`。
    * この関数は、対応する*path operation*に `request` を渡します。
    * 次に、対応する*path operation*によって生成された `response` を返します。
* その後、`response` を返す前にさらに `response` を変更することもできます。

```Python hl_lines="8-9  11  14"

If you need or want to work with **GraphQL**, <a href="https://strawberry.rocks/" class="external-link" target="_blank">**Strawberry**</a> is the **recommended** library as it has the design closest to **FastAPI's** design, it's all based on **type annotations**.

Depending on your use case, you might prefer to use a different library, but if you asked me, I would probably suggest you try **Strawberry**.

    **FastAPI** provides the same `starlette.testclient` as `fastapi.testclient` just as a convenience for you, the developer. But it comes directly from Starlette.

!!! tip
    If you want to call `async` functions in your tests apart from sending requests to your FastAPI application (e.g. asynchronous database functions), have a look at the [Async Tests](../advanced/async-tests.md){.internal-link target=_blank} in the advanced tutorial.

        self.name = name
        self.call = call
        self.use_cache = use_cache
        # Store the path to be able to re-generate a dependable from it in overrides
        self.path = path
        # Save the cache key at creation to optimize performance

                return await app(scope, receive, send)  # pragma: no cover

            async def call_next():
                return await app(scope, receive, send)

            websocket = WebSocket(scope, receive=receive, send=send)
            return await middleware_func(websocket, call_next)

        return wrapped_app

    return middleware_constructor


def test_depend_validation():

    yield request_state
    legacy_request_state_context_var.reset(contextvar_token)


@app.middleware("http")
async def custom_middleware(
    request: Request, call_next: Callable[[Request], Awaitable[Response]]
):
    response = await call_next(request)
    response.headers["custom"] = "foo"
    return response


@app.get("/user", dependencies=[Depends(set_up_request_state_dependency)])
def get_user():

    ```Python hl_lines="15"
    {!> ../../../docs_src/dependencies/tutorial012.py!}
    ```

And all the ideas in the section about [adding `dependencies` to the *path operation decorators*](dependencies-in-path-operation-decorators.md){.internal-link target=_blank} still apply, but in this case, to all of the *path operations* in the app.

## Dependencies for groups of *path operations*

{% endfor %}

</div>
{% endif %}

### FastAPI Experts - All Time

Here are the all time **FastAPI Experts**. 🤓🤯

These are the users that have [helped others the most with questions in GitHub](help-fastapi.md#help-others-with-questions-in-github){.internal-link target=_blank} through *all time*. 🧙

{% if people %}
<div class="user-list user-list-center">