text: # Copyright (C) 2014 Nippon Telegraph and Telephone Corporation.
  # Copyright (C) 2014 YAMAMOTO Takashi <yamamoto at valinux co jp>
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #    http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
  # implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  # client for ryu.app.ofctl.service
  
  from ryu.base import app_manager
  import event
  
  
  def get_datapath(app, dpid):
      """
      Get datapath object by dpid.
      Returns None on error.
      """
      assert isinstance(dpid, (int, long))
      return app.send_request(event.GetDatapathRequest(dpid=dpid))()
  
  
  def send_msg(app, msg, reply_cls=None, reply_multi=False):
      """
      Send an openflow message.
      """
      return app.send_request(event.SendMsgRequest(msg=msg,
                                                   reply_cls=reply_cls,
                                                   reply_multi=reply_multi))()
  
  
  app_manager.require_app('ryu.app.ofctl.service')
  