/// tip | Dica

Perceba que aqui estamos utilizando o `open()` da biblioteca padrão que não suporta `async` e `await`, e declaramos a operação de rota com o `def` básico.

///

### `FileResponse`

Envia um arquivo  de forma assíncrona e contínua (stream).
*

      futures.add(
          executor.submit(
              new Callable<@Nullable Void>() {
                @Override
                public @Nullable Void call() throws Exception {
                  barrier.await();
                  Integer first = graph.nodes().iterator().next();
                  for (Integer node : graph.nodes()) {
                    Set<Integer> unused = graph.successors(node);
                  }

      futures.add(
          executor.submit(
              new Callable<@Nullable Void>() {
                @Override
                public @Nullable Void call() throws Exception {
                  barrier.await();
                  Integer first = network.nodes().iterator().next();
                  for (Integer node : network.nodes()) {
                    Set<Integer> unused = network.successors(node);
                  }

AAiD,iBAAnBA,OAAOC,QAShDD,OAAOC,QAAUH,EAAOI,SACvBH,EAASD,GAAQ,GACjB,SAAUK,GACT,IAAMA,EAAED,SACP,MAAM,IAAIE,MAAO,4CAElB,OAAOL,EAASI,IAGlBJ,EAASD,GAtBX,CA0BuB,oBAAXO,OAAyBA,OAASC,KAAM,SAAUD,GAAQE,GAMtE,aAEA,IAAIC,GAAM,GAENC,EAAWC,OAAOC,eAElBC,GAAQJ,GAAII,MAEZC,EAAOL,GAAIK,KAAO,SAAUC,GAC/B,OAAON,GAAIK,KAAKE,KAAMD,IACnB,SAAUA,GACb,OAAON,GAAIQ,OAAOC,MAAO,GAAIH,IAI1BI,EAAOV,GAAIU,KAEXC,GAAUX,GAAIW,QAEdC,EAAa,GAEbC,EAAWD,EAAWC,SAEtBC,GAASF,EAAWG,eAEpBC,EAAaF,GAAOD,SAEpBI,EAAuBD,EAAWT,KAAML,QAExCgB,GAAU...

   * awkward [InterruptedException].
   */
  @Throws(InterruptedIOException::class)
  internal fun waitForIo() {
    try {
      condition.await()
    } catch (_: InterruptedException) {
      Thread.currentThread().interrupt() // Retain interrupted status.
      throw InterruptedIOException()
    }
  }

  /**

  }

  /** For testing: force this web socket to release its threads. */
  @Throws(InterruptedException::class)
  fun tearDown() {
    taskQueue.shutdown()
    taskQueue.idleLatch().await(10, TimeUnit.SECONDS)
  }

  @Synchronized fun sentPingCount(): Int = sentPingCount

  @Synchronized fun receivedPingCount(): Int = receivedPingCount

        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:

///

### 关于 `def` 对比 `async def`

*在这里，我们在路径操作函数*和依赖项中都使用着 SQLAlchemy 模型，它将与外部数据库进行通信。

这会需要一些“等待时间”。

但是由于 SQLAlchemy 不具有`await`直接使用的兼容性，因此类似于：

```Python
user = await db.query(User).first()
```

...相反，我们可以使用：

```Python
user = db.query(User).first()
```

然后我们应该声明*路径操作函数*和不带 的依赖关系`async def`，只需使用普通的`def`，如下：

            latch.countDown();
        }).error(t -> {
            t.printStackTrace();
            latch.countDown();
            fail();
        });
        latch.await();
        assertEquals(num, numObInputDoc.get());

        SuggestResponse response = suggester.suggest().setQuery("test").setSuggestDetail(true).execute().getResponse();
        assertEquals(1, response.getNum());
    }

    assertSame(exception, e.getCause());
  }

  private static void awaitUnchecked(final CyclicBarrier barrier) {
    try {
      barrier.await();
    } catch (Exception e) {
      throw new RuntimeException(e);
    }
  }

  private void checkStackTrace(ExecutionException e) {
    // Our call site for get() should be in the trace.