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# Copyright (c) 2011-2012 OpenStack, LLC.
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# Licensed under the Apache License, Version 2.0 (the "License"); you may
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# not use this file except in compliance with the License. You may obtain
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# a copy of the License at
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# http://www.apache.org/licenses/LICENSE-2.0
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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# License for the specific language governing permissions and limitations
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from stevedore import extension
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class BaseFilter(object):
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"""Base class for all filter classes."""
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def _filter_one(self, obj, filter_properties):
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"""Return True if it passes the filter, False otherwise.
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Override this in a subclass.
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def filter_all(self, filter_obj_list, filter_properties):
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"""Yield objects that pass the filter.
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Can be overriden in a subclass, if you need to base filtering
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decisions on all objects. Otherwise, one can just override
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_filter_one() to filter a single object.
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for obj in filter_obj_list:
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if self._filter_one(obj, filter_properties):
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class BaseFilterHandler(object):
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""" Base class to handle loading filter classes.
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This class should be subclassed where one needs to use filters.
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def __init__(self, filter_class_type, filter_namespace):
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self.namespace = filter_namespace
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self.filter_class_type = filter_class_type
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self.filter_manager = extension.ExtensionManager(filter_namespace)
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def _is_correct_class(self, obj):
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"""Return whether an object is a class of the correct type and
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is not prefixed with an underscore.
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return (inspect.isclass(obj) and
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not obj.__name__.startswith('_') and
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issubclass(obj, self.filter_class_type))
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def get_all_classes(self):
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return [x.plugin for x in self.filter_manager
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if self._is_correct_class(x.plugin)]
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def get_filtered_objects(self, filter_classes, objs,
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for filter_cls in filter_classes:
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objs = filter_cls().filter_all(objs, filter_properties)
added
removed
cinder/openstack/common/scheduler/filter.py
