Async creation of thumbnails with RQ

handlers.py

@route(r'/thumbnails/(?P<image>\w{1}/\w{2}/\w{6})/(?P<width>\w{1,3})'
       r'.(?P<extension>png|jpg)',
       name='thumbail')
class TileHandler(BaseHandler):

    @tornado.web.asynchronous
    @tornado.gen.engine
    def get(self, image, width, extension):
        width = int(width)

        # stick it on a queue
        q = Queue(connection=self.application.redis_connection)

        job = q.enqueue(
            make_thumbnail,
            image,
            width,
            'png',
            self.application.settings['static_path']
        )
        ioloop_instance = tornado.ioloop.IOLoop.instance()
        while True:
            yield tornado.gen.Task(
                ioloop_instance.add_timeout,
                time.time() + 1
            )
            if job.result is not None:
                thumbnail_filepath = job.result
                break

        self.set_header('Content-Type', 'image/png')
        self.write(open(thumbnail_filepath, 'rb').read())
        self.finish()