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

def get_disconnect_message(self, code: int):
        '''
        http://channels.readthedocs.io/en/stable/asgi/www.html#disconnection
        '''
        self.order += 1
        return {
            'channel': 'websocket.disconnect',
            'reply_channel': None,
            'path': self.path,
            'order': self.order,
            'code': code,
        }