new_contents: # -*- coding: utf-8 -*-
  
  from fabric.api import cd, env, run
  from .. import signal, configuration
  
  def init():
      configuration.setdefault('curl_url', '')
      configuration.setdefault('curl_options', '')
      signal.register('deploy.updating', download_artifact)
  
  def download_artifact(**kwargs):
      with cd(env.release_path):
          run('curl %(curl_url)s %(curl_options)s' % env)
  
subject: add curl plugin.