///

## Aguarde mensagens e envie mensagens { #await-for-messages-and-send-messages }

Em sua rota WebSocket você pode esperar (`await`) por mensagens e enviar mensagens.

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

Você pode receber e enviar dados binários, de texto e JSON.

* `read(size)`：讀取檔案的 `size` (`int`) 個位元組/字元。
* `seek(offset)`：移動到檔案中的位元組位置 `offset` (`int`)。
    * 例如，`await myfile.seek(0)` 會移到檔案開頭。
    * 當你已經執行過 `await myfile.read()`，之後需要再次讀取內容時特別有用。
* `close()`：關閉檔案。

由於這些都是 `async` 方法，你需要以 await 呼叫它們。

例如，在 `async` 的路徑操作函式中可這樣讀取內容：

```Python
contents = await myfile.read()
```

若是在一般的 `def` 路徑操作函式中，你可以直接存取 `UploadFile.file`，例如：

```Python

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

///

## Await for messages and send messages { #await-for-messages-and-send-messages }

In your WebSocket route you can `await` for messages and send messages.

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

You can receive and send binary, text, and JSON data.

* `seek(offset)`: Переходить до байтової позиції `offset` (`int`) у файлі.
    * Наприклад, `await myfile.seek(0)` перейде на початок файлу.
    * Це особливо корисно, якщо ви виконаєте `await myfile.read()` один раз, а потім потрібно знову прочитати вміст.
* `close()`: Закриває файл.

Оскільки всі ці методи є асинхронними `async` методами, вам потрібно їх «await»-ити.

          @Override
          protected void finalize() {
            latch.countDown();
          }
        };
    unused = null; // Hint to the JIT that unused is unreachable
    GcFinalization.await(latch);
    assertEquals(0, latch.getCount());
  }

  public void testAwaitDone_future() {
    SettableFuture<@Nullable Void> future = SettableFuture.create();
    Object unused =
        new Object() {

/// note | Teknik Detaylar

Bir `async` görev, yalnızca bir `await` noktasına geldiğinde iptal edilebilir. Eğer hiç `await` yoksa, generator (içinde `yield` olan fonksiyon) düzgün şekilde iptal edilemez ve iptal istendikten sonra bile çalışmaya devam edebilir.

Bu küçük örneğin `await` ifadesine ihtiyacı olmadığı için, event loop’un iptali ele alabilmesi adına `await anyio.sleep(0)` ekliyoruz.

Büyük veya sonsuz akışlarda bu daha da önemlidir.

    /**
     * Constructs a pipe wait request without timeout.
     *
     * @param name the pipe name to wait for
     */
    public FsctlPipeWaitRequest(final String name) {
        this.nameBytes = name.getBytes(StandardCharsets.UTF_16LE);
        this.timeoutSpecified = false;
        this.timeout = 0;
    }

    /**
     * Constructs a pipe wait request with timeout.
     *

import time

from fastapi import FastAPI, Request

app = FastAPI()


@app.middleware("http")
async def add_process_time_header(request: Request, call_next):
    start_time = time.perf_counter()
    response = await call_next(request)
    process_time = time.perf_counter() - start_time
    response.headers["X-Process-Time"] = str(process_time)

Dann können wir einen `AsyncClient` mit der App erstellen und mit `await` asynchrone Requests an ihn senden.

{* ../../docs_src/async_tests/app_a_py310/test_main.py hl[9:12] *}

Das ist das Äquivalent zu:

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

... welches wir verwendet haben, um unsere Requests mit dem `TestClient` zu machen.

/// tip | Tipp

Then we can create an `AsyncClient` with the app, and send async requests to it, using `await`.

{* ../../docs_src/async_tests/app_a_py310/test_main.py hl[9:12] *}

This is the equivalent to:

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

...that we used to make our requests with the `TestClient`.

/// tip

Note that we're using async/await with the new `AsyncClient` - the request is asynchronous.

///

/// warning