cinder/cinder/scheduler/driver.py

101 lines
3.9 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
"""
from oslo.config import cfg
from cinder import db
from cinder.i18n import _
from cinder.openstack.common import importutils
from cinder.openstack.common import timeutils
from cinder.volume import rpcapi as volume_rpcapi
scheduler_driver_opts = [
cfg.StrOpt('scheduler_host_manager',
default='cinder.scheduler.host_manager.HostManager',
help='The scheduler host manager class to use'),
cfg.IntOpt('scheduler_max_attempts',
default=3,
help='Maximum number of attempts to schedule an volume'),
]
CONF = cfg.CONF
CONF.register_opts(scheduler_driver_opts)
def volume_update_db(context, volume_id, host):
'''Set the host and set the scheduled_at field of a volume.
:returns: A Volume with the updated fields set properly.
'''
now = timeutils.utcnow()
values = {'host': host, 'scheduled_at': now}
return db.volume_update(context, volume_id, values)
def group_update_db(context, group_id, host):
"""Set the host and the scheduled_at field of a consistencygroup.
:returns: A Consistencygroup with the updated fields set properly.
"""
now = timeutils.utcnow()
values = {'host': host, 'updated_at': now}
return db.consistencygroup_update(context, group_id, values)
class Scheduler(object):
"""The base class that all Scheduler classes should inherit from."""
def __init__(self):
self.host_manager = importutils.import_object(
CONF.scheduler_host_manager)
self.volume_rpcapi = volume_rpcapi.VolumeAPI()
def update_service_capabilities(self, service_name, host, capabilities):
"""Process a capability update from a service node."""
self.host_manager.update_service_capabilities(service_name,
host,
capabilities)
def host_passes_filters(self, context, volume_id, host, filter_properties):
"""Check if the specified host passes the filters."""
raise NotImplementedError(_("Must implement host_passes_filters"))
def find_retype_host(self, context, request_spec, filter_properties=None,
migration_policy='never'):
"""Find a host that can accept the volume with its new type."""
raise NotImplementedError(_("Must implement find_retype_host"))
def schedule(self, context, topic, method, *_args, **_kwargs):
"""Must override schedule method for scheduler to work."""
raise NotImplementedError(_("Must implement a fallback schedule"))
def schedule_create_volume(self, context, request_spec, filter_properties):
"""Must override schedule method for scheduler to work."""
raise NotImplementedError(_("Must implement schedule_create_volume"))
def schedule_create_consistencygroup(self, context, group_id,
request_spec_list,
filter_properties_list):
"""Must override schedule method for scheduler to work."""
raise NotImplementedError(_(
"Must implement schedule_create_consistencygroup"))