app = FastAPI()

        @app.websocket("/ws")
        async def websocket_endpoint(websocket: WebSocket):
            await websocket.accept()
            while True:
                data = await websocket.receive_text()
                await websocket.send_text(f"Message text was: {data}")
        ```
        """

        def decorator(func: DecoratedCallable) -> DecoratedCallable:

Luego podemos crear un `AsyncClient` con la app y enviar requests asíncronos a ella, usando `await`.

{* ../../docs_src/async_tests/app_a_py39/test_main.py hl[9:12] *}

Esto es equivalente a:

```Python
response = client.get('/')
```

...que usábamos para hacer nuestros requests con el `TestClient`.

/// tip | Consejo

Nota que estamos usando async/await con el nuevo `AsyncClient`: el request es asíncrono.

///

# 並行処理と async / await

*path operation 関数*のための `async def` に関する詳細と非同期 (asynchronous) コード、並行処理 (Concurrency)、そして、並列処理 (Parallelism) の背景について。

## 急いでいますか？

<abbr title="too long; didn't read (長すぎて読めない人のための要約という意味のスラング)"><strong>TL;DR:</strong></abbr>

次のような、`await` を使用して呼び出すべきサードパーティライブラリを使用している場合:

```Python
results = await some_library()
```

以下の様に `async def` を使用して*path operation 関数*を宣言します。

```Python hl_lines="2"
@app.get('/')

    assertEquals(3L, countDownLatch.getCount());

    list.execute();

    // Verify that all of the runnables execute in a reasonable amount of time.
    assertTrue(countDownLatch.await(1L, SECONDS));
  }

  public void testExecute_idempotent() {
    AtomicInteger runCalled = new AtomicInteger();
    list.add(
        new Runnable() {
          @Override
          public void run() {

  /**
   * No-op null-pointer test for {@link LongAdder} to override the {@link PackageSanityTests}
   * version, which checks package-private methods that we don't want to have to annotate as {@code
   * Nullable} because we don't want diffs from jsr166e.
   */
  public void testNulls() {}

  public void testOverflows() {
    LongAdder longAdder = new LongAdder();
    longAdder.add(Long.MAX_VALUE);

          required: true
        - label: I am a native speaker of the language I want to help translate.
          required: true
  - type: input
    id: language
    attributes:
      label: Target Language
      description: What language do you want to translate the FastAPI docs into?
      placeholder: e.g. Latin
    validations:
      required: true
  - type: textarea

    client = DummyClient()
    yield client
    await client.close()


Client = Annotated[DummyClient, Depends(get_client)]


@pytest.fixture(name="client")
def client_fixture() -> TestClient:
    app = FastAPI()

    @app.get("/")
    async def get_people(client: Client) -> list:
        return await client.get_people()

    client = TestClient(app)
    return client

@app.websocket("/items/{item_id}")
async def websocket_item(item_id: str, websocket: WebSocket):
    route: APIWebSocketRoute = websocket.scope["route"]
    await websocket.accept()
    await websocket.send_json({"item_id": item_id, "path": route.path})


client = TestClient(app)


def test_get():
    response = client.get("/users/rick")

<span style="color: green;">INFO</span>:     Waiting for application startup.
<span style="color: green;">INFO</span>:     Application startup complete.
```

</div>

/// note

La commande `uvicorn main:app` fait référence à :

* `main` : le fichier `main.py` (le module Python).
* `app` : l'objet créé dans `main.py` via la ligne `app = FastAPI()`.

    "version" that omits the class to avoid conflicts with the copy in Guava
    itself. The idea is:

    - If users want only ListenableFuture, they depend on listenablefuture-1.0.

    - If users want all of Guava, they depend on guava, which, as of Guava
    27.0, depends on
    listenablefuture-9999.0-empty-to-avoid-conflict-with-guava. The 9999.0-...