text: #
  #    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 oslo_config import cfg
  
  from heat.api.openstack.v1 import util
  from heat.common import serializers
  from heat.common import wsgi
  from heat.rpc import client as rpc_client
  
  
  class BuildInfoController(object):
      """
      WSGI controller for BuildInfo in Heat v1 API
      Returns build information for current app
      """
      # Define request scope (must match what is in policy.json)
      REQUEST_SCOPE = 'build_info'
  
      def __init__(self, options):
          self.options = options
          self.rpc_client = rpc_client.EngineClient()
  
      @util.policy_enforce
      def build_info(self, req):
          engine_revision = self.rpc_client.get_revision(req.context)
          build_info = {
              'api': {'revision': cfg.CONF.revision['heat_revision']},
              'engine': {'revision': engine_revision}
          }
  
          return build_info
  
  
  def create_resource(options):
      """
      BuildInfo factory method.
      """
      deserializer = wsgi.JSONRequestDeserializer()
      serializer = serializers.JSONResponseSerializer()
      return wsgi.Resource(BuildInfoController(options), deserializer,
                           serializer)
  