57 lines
1.6 KiB
Python
57 lines
1.6 KiB
Python
# -*- coding: utf-8 -*-
|
|
|
|
# Copyright 2014 Mirantis, Inc.
|
|
#
|
|
# 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 six
|
|
|
|
|
|
@six.add_metaclass(abc.ABCMeta)
|
|
class UpgradeEngine(object):
|
|
"""Base class for all upgraders.
|
|
|
|
The main purpose of this class is to declare interface, which must be
|
|
respected by all upgraders.
|
|
"""
|
|
def __init__(self, config):
|
|
"""Extract some base parameters and save it internally."""
|
|
self.config = config
|
|
|
|
@abc.abstractmethod
|
|
def upgrade(self):
|
|
"""Run upgrade process."""
|
|
|
|
@abc.abstractmethod
|
|
def rollback(self):
|
|
"""Rollback all the changes, usually used in case of failed upgrade"""
|
|
|
|
def backup(self):
|
|
"""Perform backup actions"""
|
|
return NotImplemented
|
|
|
|
@abc.abstractproperty
|
|
def required_free_space(self):
|
|
"""Required free space for upgrade
|
|
|
|
Must return dict where key is path to directory
|
|
and value is required free space in megabytes.
|
|
|
|
Example:
|
|
{
|
|
"/var/www/nailgun": 2000,
|
|
"/var/lib/docker": 5000,
|
|
"/etc/supervisor.d": 10,
|
|
}
|
|
"""
|