http://channels.readthedocs.io/en/stable/asgi/www.html#request

def get_message(self, transport, http_version: str, method: bytes,
                    url: bytes, headers: List[List[bytes]]) -> Dict[str, Any]:
        '''
        http://channels.readthedocs.io/en/stable/asgi/www.html#request
        '''
        url_obj = parse_url(url)
        if url_obj.schema is None:
            if transport.get_extra_info('sslcontext'):
                scheme = 'https'
            else:
                scheme = 'http'
        else:
            scheme = url_obj.schema.decode()
        path = '' if url_obj.path is None else url_obj.path.decode('utf-8')
        query = b'' if url_obj.query is None else url_obj.query
        return {
            'channel': 'http.request',
            'reply_channel': None,
            'http_version': http_version,
            'method': method.decode(),
            'scheme': scheme,
            'path': path,
            'query_string': query,
            'root_path': '',
            'headers': headers,
            'body': b'',
            'body_channel': None,
            'client': transport.get_extra_info('peername'),
            'server': transport.get_extra_info('sockname')
        }