nova/nova/scheduler/api.py

73 lines
2.5 KiB
Python

# Copyright (c) 2011 OpenStack, LLC.
# 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.
"""
Handles all requests relating to schedulers.
"""
from nova import flags
from nova import log as logging
from nova import rpc
FLAGS = flags.FLAGS
LOG = logging.getLogger(__name__)
def _call_scheduler(method, context, params=None):
"""Generic handler for RPC calls to the scheduler.
:param params: Optional dictionary of arguments to be passed to the
scheduler worker
:retval: Result returned by scheduler worker
"""
if not params:
params = {}
queue = FLAGS.scheduler_topic
kwargs = {'method': method, 'args': params}
return rpc.call(context, queue, kwargs)
def get_host_list(context):
"""Return a list of hosts associated with this zone."""
return _call_scheduler('get_host_list', context)
def get_service_capabilities(context):
"""Return aggregated capabilities for all services."""
return _call_scheduler('get_service_capabilities', context)
def update_service_capabilities(context, service_name, host, capabilities):
"""Send an update to all the scheduler services informing them
of the capabilities of this service."""
kwargs = dict(method='update_service_capabilities',
args=dict(service_name=service_name, host=host,
capabilities=capabilities))
return rpc.fanout_cast(context, 'scheduler', kwargs)
def live_migration(context, block_migration, disk_over_commit,
instance_id, dest, topic):
"""Migrate a server to a new host"""
params = {"instance_id": instance_id,
"dest": dest,
"topic": topic,
"block_migration": block_migration,
"disk_over_commit": disk_over_commit}
# NOTE(comstud): Call vs cast so we can get exceptions back, otherwise
# this call in the scheduler driver doesn't return anything.
_call_scheduler("live_migration", context=context, params=params)