# Copyright 2011 OpenStack Foundation.
# All Rights Reserved.
#
#    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.

import abc
import collections

import six

HealthcheckResult = collections.namedtuple(
    'HealthcheckResult', ['available', 'reason'])


@six.add_metaclass(abc.ABCMeta)
class HealthcheckBaseExtension(object):
    def __init__(self, conf):
        self.conf = conf

    @abc.abstractmethod
    def healthcheck(self, server_port):
        """method called by the healthcheck middleware

        return: HealthcheckResult object
        """