nova/nova/scheduler/filters/compute_capabilities_filter.py

83 lines
3.2 KiB
Python

# Copyright (c) 2011 OpenStack Foundation
# 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.
from oslo.serialization import jsonutils
import six
from nova.openstack.common import log as logging
from nova.scheduler import filters
from nova.scheduler.filters import extra_specs_ops
LOG = logging.getLogger(__name__)
class ComputeCapabilitiesFilter(filters.BaseHostFilter):
"""HostFilter hard-coded to work with InstanceType records."""
# Instance type and host capabilities do not change within a request
run_filter_once_per_request = True
def _satisfies_extra_specs(self, host_state, instance_type):
"""Check that the host_state provided by the compute service
satisfy the extra specs associated with the instance type.
"""
if 'extra_specs' not in instance_type:
return True
for key, req in instance_type['extra_specs'].iteritems():
# Either not scope format, or in capabilities scope
scope = key.split(':')
if len(scope) > 1:
if scope[0] != "capabilities":
continue
else:
del scope[0]
cap = host_state
for index in range(0, len(scope)):
try:
if isinstance(cap, six.string_types):
try:
cap = jsonutils.loads(cap)
except ValueError:
return False
if not isinstance(cap, dict):
if getattr(cap, scope[index], None) is None:
# If can't find, check stats dict
cap = cap.stats.get(scope[index], None)
else:
cap = getattr(cap, scope[index], None)
else:
cap = cap.get(scope[index], None)
except AttributeError:
return False
if cap is None:
return False
if not extra_specs_ops.match(str(cap), req):
LOG.debug("extra_spec requirement '%(req)s' does not match "
"'%(cap)s'", {'req': req, 'cap': cap})
return False
return True
def host_passes(self, host_state, filter_properties):
"""Return a list of hosts that can create instance_type."""
instance_type = filter_properties.get('instance_type')
if not self._satisfies_extra_specs(host_state,
instance_type):
LOG.debug("%(host_state)s fails instance_type extra_specs "
"requirements", {'host_state': host_state})
return False
return True