52 lines
1.9 KiB
Python
52 lines
1.9 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
|
|
|
|
from nova import objects
|
|
from nova.scheduler import host_manager
|
|
from nova import servicegroup
|
|
|
|
|
|
class Scheduler(metaclass=abc.ABCMeta):
|
|
"""The base class that all Scheduler classes should inherit from."""
|
|
|
|
def __init__(self):
|
|
self.host_manager = host_manager.HostManager()
|
|
self.servicegroup_api = servicegroup.API()
|
|
|
|
def hosts_up(self, context, topic):
|
|
"""Return the list of hosts that have a running service for topic."""
|
|
|
|
services = objects.ServiceList.get_by_topic(context, topic)
|
|
return [service.host
|
|
for service in services
|
|
if self.servicegroup_api.service_is_up(service)]
|
|
|
|
@abc.abstractmethod
|
|
def select_destinations(self, context, spec_obj, instance_uuids,
|
|
alloc_reqs_by_rp_uuid, provider_summaries,
|
|
allocation_request_version=None, return_alternates=False):
|
|
"""Returns a list of lists of Selection objects that have been chosen
|
|
by the scheduler driver, one for each requested instance.
|
|
"""
|
|
return []
|