/// note | 技术细节

您也可以使用 `from starlette.websockets import WebSocket`。

**FastAPI** 直接提供了相同的 `WebSocket`，只是为了方便开发人员。但它直接来自 Starlette。

///

## 等待消息并发送消息 { #await-for-messages-and-send-messages }

在您的 WebSocket 路由中，您可以使用 `await` 等待消息并发送消息。

{* ../../docs_src/websockets_/tutorial001_py310.py hl[48:52] *}

您可以接收和发送二进制、文本和 JSON 数据。

## 尝试一下 { #try-it }

将代码放在 `main.py`，然后运行你的应用程序：

        for (int t = 0; t < numThreads; t++) {
            final int threadId = t;
            executor.submit(() -> {
                try {
                    startLatch.await();
                    for (int i = 0; i < eventsPerThread; i++) {
                        helper.offer(new LogNotificationEvent(i, "ERROR", "org.test", "t" + threadId + "-" + i, null));

* `read(size)`: Lê `size` (`int`) bytes/caracteres do arquivo.
* `seek(offset)`: Vai para o byte na posição `offset` (`int`) no arquivo.
    * Por exemplo, `await myfile.seek(0)` irá para o início do arquivo.
    * Isso é especialmente útil se você executar `await myfile.read()` uma vez e precisar ler o conteúdo novamente.
* `close()`: Fecha o arquivo.

Como todos esses métodos são métodos `assíncronos`, você precisa "aguardar" por eles.

///

## Nachrichten erwarten und Nachrichten senden { #await-for-messages-and-send-messages }

In Ihrer WebSocket-Route können Sie Nachrichten `await`en und Nachrichten senden.

{* ../../docs_src/websockets_/tutorial001_py310.py hl[48:52] *}

Sie können Binär-, Text- und JSON-Daten empfangen und senden.

                                        with anyio.fail_after(_PING_INTERVAL):
                                            data = await receive_stream.receive()
                                        await send_keepalive.send(data)
                                    except TimeoutError:
                                        await send_keepalive.send(KEEPALIVE_COMMENT)
                            except anyio.EndOfStream:

    /**
     * Any file name change in the watched directory or subtree causes a change notification wait operation to return.
     * Changes include renaming, creating, or deleting a file.
     */
    int FILE_NOTIFY_CHANGE_FILE_NAME = 0x00000001;

    /**
     * Any directory-name change in the watched directory or subtree causes a change notification wait operation to
     * return. Changes include creating or deleting a directory.
     */

      // SequentialExecutor by the time the barrier is satisfied
      barrier.await(1, SECONDS);
      executor.execute(barrierTask);
      // timeout means the second task wasn't even tried
      barrier.await(1, SECONDS);
    } finally {
      service.shutdown();
    }
  }

  public void testRejectedExecutionThrownWithMultipleCalls() throws Exception {

`from starlette.websockets import WebSocket`을 사용할 수도 있습니다.

**FastAPI**는 개발자를 위한 편의를 위해 동일한 `WebSocket`을 직접 제공합니다. 하지만 이는 Starlette에서 가져옵니다.

///

## 메시지를 대기하고 전송하기 { #await-for-messages-and-send-messages }

WebSocket 경로에서 메시지를 대기(`await`)하고 전송할 수 있습니다.

{* ../../docs_src/websockets_/tutorial001_py310.py hl[48:52] *}

여러분은 이진 데이터, 텍스트, JSON 데이터를 받을 수 있고 전송할 수 있습니다.

## 시도해보기 { #try-it }

/// note | Détails techniques

Une tâche `async` ne peut être annulée que lorsqu'elle atteint un `await`. S'il n'y a pas de `await`, le générateur (fonction avec `yield`) ne peut pas être annulé correctement et peut continuer à s'exécuter même après la demande d'annulation.

Comme ce petit exemple n'a besoin d'aucune instruction `await`, nous ajoutons un `await anyio.sleep(0)` pour donner une chance à la boucle d'événements de gérer l'annulation.

                use_astack = function_astack
            solved = await _solve_generator(
                dependant=use_sub_dependant,
                stack=use_astack,
                sub_values=solved_result.values,
            )
        elif use_sub_dependant.is_coroutine_callable:
            solved = await call(**solved_result.values)
        else:
            solved = await run_in_threadpool(call, **solved_result.values)