OpenStack Study: availability_zone_filter.py

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# Copyright (c) 2011-2012 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 cinder.openstack.common.scheduler import filters

**** CubicPower OpenStack Study ****

class AvailabilityZoneFilter(filters.BaseHostFilter):

"""Filters Hosts by availability zone."""

**** CubicPower OpenStack Study ****

    def host_passes(self, host_state, filter_properties):

        spec = filter_properties.get('request_spec', {})

        props = spec.get('resource_properties', {})

        availability_zone = props.get('availability_zone')

        if availability_zone:

            return availability_zone == host_state.service['availability_zone']

        return True