text: # -*- coding: utf-8 -*-
  """
  Tencent is pleased to support the open source community by making 蓝鲸智云PaaS平台社区版 (BlueKing PaaS Community Edition) available.
  Copyright (C) 2017-2018 THL A29 Limited, a Tencent company. All rights reserved.
  Licensed under the MIT License (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
  http://opensource.org/licenses/MIT
  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.
  """ # noqa
  from guardian.shortcuts import get_perms
  
  from permission.models import Business
  
  
  class PermissionBackend(object):
  
      def authenticate(self, username, password):
          """
          We do not authenticate user in this backend, so always return None.
          """
          return None
  
      def has_perm(self, user_obj, perm, obj=None):
          """
          If a user has manage_business perm for a exact business instance,
          he/she has all other perms of this business and related objects.
          """
          if isinstance(obj, Business):
              business = obj
          else:
              business = getattr(obj, 'business', None)
  
          if (isinstance(business, Business) and 'manage_business' in get_perms(user_obj, business)):
              return True
  