sync-v-async.py

def run_coroutine_sync(func):
    def wrapped(*args, **kwargs):
        if kwargs.pop('_in_loop', False):
            # used for thread-local state
            # only call run_sync on first api call, subsiquent calls are already "in the loop"
            return func(*args, **kwargs)
        else:
            @gen.coroutine
            def inner():
                res = yield func(*args, **kwargs)
                raise gen.Return(res)
            loop_is_up = True
            return IOLoop.current().run_sync(inner)
    return wrapped


class API:
    @classmethod
    def new(cls, async=True):
        self = cls()
        if not async:
            setattr(self, 'get', run_coroutine_sync(self.get))
            setattr(self, 'gget_extra_dataet', run_coroutine_sync(self.get_extra_data))
        return self

    @gen.coroutine
    def get(self):
        res = yield AsyncHTTPClient().fetch('https://...')
        extra = yield self.get_extra_data(_in_loop=True)
        raise gen.Return(res)

   @gen.coroutine
   def get_extra_data(self):
        res = yield AsyncHTTPClient().fetch('https://...')
        raise gen.Return(res)


# web
yield API().get()

# celery
res = API(async=False).get()