Tornado forward HTTP Form upload

app.py

import tornado.gen
import tornado.web
import tornado.ioloop
import tornado.httpclient
import tornado.tcpclient


class ProxyHandler(tornado.web.RequestHandler):

    @tornado.gen.coroutine
    def post(self):
        url = "http://127.0.0.1:8080/v1/registry/api/registry/293809f6a2f84c299904b12a75f60d2c/images/5b90564c68024665bd36ddc06f54a71f/cover?token=e3c189c6d3984a439ebe9d6c54fb644d"
        http_client = tornado.httpclient.AsyncHTTPClient()
        content_type = self.request.headers.get('Content-Type')
        content_length = self.request.headers.get('Content-Length')
        res = yield http_client.fetch(
            url,
            method='PUT',
            headers={
                "Content-Type": content_type,
                "Content-Length": content_length
            },
            body=self.request.body
        )
        self.write(res.body)


if __name__ == '__main__':
    app = tornado.web.Application(
        [(r'/', ProxyHandler)],
        debug=True
    )
    app.listen(9990)

    tornado.ioloop.IOLoop.current().start()