# 동시성과 async / await

*경로 작동 함수*에서의 `async def` 문법에 대한 세부사항과 비동기 코드, 동시성 및 병렬성에 대한 배경

## 바쁘신 경우

<strong>요약</strong>

다음과 같이 `await`를 사용해 호출하는 제3의 라이브러리를 사용하는 경우:

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

다음처럼 *경로 작동 함수*를 `async def`를 사용해 선언하십시오:

```Python hl_lines="2"
@app.get('/')
async def read_results():
    results = await some_library()
    return results
```

/// note | "참고"

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

	if g != nil {
		g.retryCount = retryCount
	}
	return g
}

// Wait blocks until all function calls from the Go method have returned, then
// returns the slice of errors from all function calls.
func (g *NotificationGroup) Wait() []NotificationPeerErr {
	g.workers.Wait()
	return g.errs
}

// Go calls the given function in a new goroutine.
//

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

                        continue;
                    }

                    curResp.wait();
                    if ( handleIntermediate(request, curResp) ) {
                        continue;
                    }
                    if ( log.isDebugEnabled() ) {
                        log.debug("Wait returned state is " + this.state);
                    }
                    if ( isDisconnected() ) {

    callback.await(server.url("/a")).assertBody("abc")
    client.newCall(Request.Builder().url(server.url("/b")).build()).enqueue(callback)
    callback.await(server.url("/b")).assertBody("def")
    client.newCall(Request.Builder().url(server.url("/c")).build()).enqueue(callback)
    callback.await(server.url("/c")).assertBody("ghi")

     * 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.
     */
    public static final 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.
     */

        });
        th.start();

        final CountDownLatch latch = new CountDownLatch(1);
        deferred.promise().then(response -> latch.countDown());
        assertTrue(latch.await(10, TimeUnit.SECONDS));
    }

    @Test
    public void test_doneAfterResolve() throws Exception {
        final Deferred<SuggestResponse> deferred = new Deferred<>();

        Thread th = new Thread(() -> {

        return inner

    async def __call__(self, scope, receive, send):
        if scope["type"] != "http" or self.max_content_size is None:
            await self.app(scope, receive, send)
            return

        wrapper = self.receive_wrapper(receive)
        await self.app(scope, wrapper, send)


@router.post("/middleware")
def run_middleware(file: UploadFile = File(..., description="Big File")):

# 并发 async / await

有关路径操作函数的 `async def` 语法以及异步代码、并发和并行的一些背景知识。

## 赶时间吗？

<abbr title="too long; didn't read(长文警告)"><strong>TL;DR:</strong></abbr>

如果你正在使用第三方库，它们会告诉你使用 `await` 关键字来调用它们，就像这样：

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

然后，通过 `async def` 声明你的 *路径操作函数*：

```Python hl_lines="2"
@app.get('/')
async def read_results():
    results = await some_library()
    return results
```

/// note