text: # Copyright 2019 NullConvergence
  #
  # 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.
  
  """This module stores all config constants. It is a singleton
  because it is used across several modules inside the app"""
  
  from graphrepo.singleton import Singleton
  from graphrepo.utils import Dotdict
  
  
  class Config(metaclass=Singleton):
      """This class contains all config flags"""
      ct = {}
  
      def configure(self, **kwargs):
          """Stores configuration contants, parsed
          from yaml config file
          :param kwargs: keys and values from config
          """
          self.ct = Dotdict(kwargs)
  
      def check_config(self):
          """Checks if the config properties are set and
          raises ValueError if any value misses"""
  
          if not self.ct.db_url or not self.ct.port \
                  or not self.ct.db_user or not self.ct.db_pwd:
              raise ValueError("Neo4j configuartion is invalid.")
  