tornadoweb.py 文件源码

def call(self, fn, *args, **kwargs):
        self.begin(fn)

        result = NO_RESULT
        exc_info = None
        start_time = now()

        while True:
            do = self.iter(result=result, exc_info=exc_info,
                           start_time=start_time)
            if isinstance(do, DoAttempt):
                try:
                    result = yield fn(*args, **kwargs)
                    exc_info = None
                    continue
                except Exception:
                    result = NO_RESULT
                    exc_info = sys.exc_info()
                    continue
            elif isinstance(do, DoSleep):
                result = NO_RESULT
                exc_info = None
                yield self.sleep(do)
            else:
                raise gen.Return(do)