# -*- coding: utf-8 -*-

# vim: tabstop=4 shiftwidth=4 softtabstop=4

#    Copyright (C) 2012 Yahoo! Inc. 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


class Catalog(object):
    """A catalog can [create, fetch, erase] logbooks for jobs"""

    __metaclass__ = abc.ABCMeta

    @abc.abstractmethod
    def __contains__(self, job):
        """Checks if the given catalog has a logbook for a job."""
        raise NotImplementedError()

    def __len__(self):
        """Gets how many logbooks are in this catalog."""
        raise NotImplementedError()

    @abc.abstractmethod
    def create_or_fetch(self, job):
        """Creates a new logbook for a job or gives back an old one."""
        raise NotImplementedError()

    @abc.abstractmethod
    def erase(self, job):
        """Erases a existing logbook for a job."""
        raise NotImplementedError()

    def close(self):
        """Allows the catalog to free any resources that it has."""
        pass