text: # Copyright (C) 2013 eNovance SAS <licensing@enovance.com>
  #
  # 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.
  
  from neutron.api.rpc.agentnotifiers import metering_rpc_agent_api
  from neutron.common import rpc as n_rpc
  from neutron.common import topics
  from neutron.db.metering import metering_db
  from neutron.db.metering import metering_rpc
  
  
  class MeteringPlugin(metering_db.MeteringDbMixin):
      """Implementation of the Neutron Metering Service Plugin."""
      supported_extension_aliases = ["metering"]
      path_prefix = "/metering"
  
      def __init__(self):
          super(MeteringPlugin, self).__init__()
  
          self.endpoints = [metering_rpc.MeteringRpcCallbacks(self)]
  
          self.conn = n_rpc.create_connection(new=True)
          self.conn.create_consumer(
              topics.METERING_PLUGIN, self.endpoints, fanout=False)
          self.conn.consume_in_threads()
  
          self.meter_rpc = metering_rpc_agent_api.MeteringAgentNotifyAPI()
  
      def create_metering_label(self, context, metering_label):
          label = super(MeteringPlugin, self).create_metering_label(
              context, metering_label)
  
          data = self.get_sync_data_metering(context)
          self.meter_rpc.add_metering_label(context, data)
  
          return label
  
      def delete_metering_label(self, context, label_id):
          data = self.get_sync_data_metering(context, label_id)
          label = super(MeteringPlugin, self).delete_metering_label(
              context, label_id)
  
          self.meter_rpc.remove_metering_label(context, data)
  
          return label
  
      def create_metering_label_rule(self, context, metering_label_rule):
          rule = super(MeteringPlugin, self).create_metering_label_rule(
              context, metering_label_rule)
  
          data = self.get_sync_data_for_rule(context, rule)
          self.meter_rpc.add_metering_label_rule(context, data)
  
          return rule
  
      def delete_metering_label_rule(self, context, rule_id):
          rule = super(MeteringPlugin, self).delete_metering_label_rule(
              context, rule_id)
  
          data = self.get_sync_data_for_rule(context, rule)
          self.meter_rpc.remove_metering_label_rule(context, data)
          return rule
  