zun/zun/scheduler/driver.py

54 lines
1.8 KiB
Python

# Copyright (c) 2010 OpenStack Foundation
# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# 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.
"""
Scheduler base class that all Schedulers should inherit from
"""
import abc
import six
from zun.api import servicegroup
from zun import objects
@six.add_metaclass(abc.ABCMeta)
class Scheduler(object):
"""The base class that all Scheduler classes should inherit from."""
def __init__(self):
self.servicegroup_api = servicegroup.ServiceGroup()
def hosts_up(self, context):
"""Return the list of hosts that have a running service."""
services = objects.ZunService.list_by_binary(context, 'zun-compute')
return [service.host
for service in services
if self.servicegroup_api.service_is_up(service)
and not service.disabled]
@abc.abstractmethod
def select_destinations(self, context, containers, extra_spec):
"""Must override select_destinations method.
:return: A list of dicts with 'host', 'nodename' and 'limits' as keys
that satisfies the extra_spec and filter_properties.
"""
raise NotImplementedError()