Question

我在龙卷风Web应用程序的标题中使用tornado.httpclient.AsyncHTTPClient。

这是我的代码

class CustomTornadoHandler(tornado.web.RequestHandler):

    def set_default_headers(self):
        self.set_header("Access-Control-Allow-Origin", "*")
        self.set_header("Access-Control-Allow-Headers", "x-requested-with,application/x-www-form-urlencoded")
        self.set_header('Access-Control-Allow-Methods', 'POST, GET, OPTIONS, PATCH, DELETE, PUT')

    def initialize(self, *args, **kwargs):
        self.db_session = db_session()

    def on_finish(self):
        db_session.remove()


class AdminUploadAlignerParagraphTaskHandler(CustomTornadoHandler):

    executor = concurrent.futures.ThreadPoolExecutor()

    @run_on_executor
    def post(self):

        async def f():
            http_client = tornado.httpclient.AsyncHTTPClient()
            try:
                response = await http_client.fetch("http://www.google.com")
            except Exception as e:
                print("Error: %s" % e)
            else:
                logging.info(response.body)
        ...
        self.write("")
        f()

我在https://www.tornadoweb.org/en/stable/httpclient.html中得到了示例。但这不起作用：

RuntimeWarning: coroutine 'AdminUploadAlignerParagraphTaskHandler.post.<locals>.f' was never awaited
  f()
RuntimeWarning: Enable tracemalloc to get the object allocation traceback

我该怎么办？

Answer 1

函数f()是一个协程，您只是在不等待的情况下调用它。您需要使用await f()来调用它。为此，您还需要将post方法转换为协程。

您不必要地使post方法复杂化。我不明白为什么要在单独的线程上运行它。

这是我要重写的方式：

# no need to run on separate thread
async def post():
    http_client = tornado.httpclient.AsyncHTTPClient()

    try:
        response = await http_client.fetch("http://www.google.com")
    except Exception as e:
        print("Error: %s" % e)
    else:
        logging.info(response.body)

    ...

    self.write("")

使用tornado.httpclient.AsyncHTTPClient时如何解决“ RuntimeWarning：启用tracemalloc以获取对象分配回溯”？

1 个答案: