Move oslo-incubator's scheduler module to cinder

oslo-incubator is ending its life and we should move remaining
dependencies from there to cinder namespace. This commit does so with
openstack.common.scheduler. Apart from that tests from oslo-incubator
repository are added.

Change-Id: I10d88c120c9c847826986483065f5493e91f89d6
Closes-Bug: 1519337

cinder/openstack/common/scheduler/base_filter.py → cinder/scheduler/base_filter.py

@@ -19,7 +19,7 @@
 import logging
 
 from cinder.openstack.common._i18n import _LI
-from cinder.openstack.common.scheduler import base_handler
+from cinder.scheduler import base_handler
 
 LOG = logging.getLogger(__name__)
 
@@ -28,6 +28,7 @@ class BaseFilter(object):
     """Base class for all filter classes."""
     def _filter_one(self, obj, filter_properties):
         """Return True if it passes the filter, False otherwise.
+
         Override this in a subclass.
         """
         return True
@@ -48,9 +49,10 @@ def filter_all(self, filter_obj_list, filter_properties):
     run_filter_once_per_request = False
 
     def run_filter_for_index(self, index):
-        """Return True if the filter needs to be run for the "index-th"
-        instance in a request.  Only need to override this if a filter
-        needs anything other than "first only" or "all" behaviour.
+        """Return True if the filter needs to be run for n-th instances.
+
+        Only need to override this if a filter needs anything other than
+        "first only" or "all" behaviour.
         """
         return not (self.run_filter_once_per_request and index > 0)
 

cinder/openstack/common/scheduler/base_handler.py → cinder/scheduler/base_handler.py

@@ -32,8 +32,9 @@ def __init__(self, modifier_class_type, modifier_namespace):
         self.extension_manager = extension.ExtensionManager(modifier_namespace)
 
     def _is_correct_class(self, cls):
-        """Return whether an object is a class of the correct type and
-        is not prefixed with an underscore.
+        """Return whether an object is a class of the correct type.
+
+        (or is not prefixed with an underscore)
         """
         return (inspect.isclass(cls) and
                 not cls.__name__.startswith('_') and

cinder/openstack/common/scheduler/base_weight.py → cinder/scheduler/base_weight.py

@@ -21,7 +21,7 @@
 
 import six
 
-from cinder.openstack.common.scheduler import base_handler
+from cinder.scheduler import base_handler
 
 
 def normalize(weight_list, minval=None, maxval=None):
@@ -87,9 +87,7 @@ def weight_multiplier(self):
 
     @abc.abstractmethod
     def _weigh_object(self, obj, weight_properties):
-        """Override in a subclass to specify a weight for a specific
-        object.
-        """
+        """Override in a subclass to specify a weight for a specific object."""
 
     def weigh_objects(self, weighed_obj_list, weight_properties):
         """Weigh multiple objects.

cinder/scheduler/filters/__init__.py

@@ -0,0 +1,39 @@
+# 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.
+
+"""
+Scheduler host filters
+"""
+
+from cinder.scheduler import base_filter
+
+
+class BaseHostFilter(base_filter.BaseFilter):
+    """Base class for host filters."""
+    def _filter_one(self, obj, filter_properties):
+        """Return True if the object passes the filter, otherwise False."""
+        return self.host_passes(obj, filter_properties)
+
+    def host_passes(self, host_state, filter_properties):
+        """Return True if the HostState passes the filter, otherwise False.
+
+        Override this in a subclass.
+        """
+        raise NotImplementedError()
+
+
+class HostFilterHandler(base_filter.BaseFilterHandler):
+    def __init__(self, namespace):
+        super(HostFilterHandler, self).__init__(BaseHostFilter, namespace)

cinder/scheduler/filters/affinity_filter.py

@@ -17,7 +17,7 @@
 from oslo_log import log as logging
 from oslo_utils import uuidutils
 
-from cinder.openstack.common.scheduler import filters
+from cinder.scheduler import filters
 from cinder.volume import api as volume
 
 LOG = logging.getLogger(__name__)

cinder/openstack/common/scheduler/filters/availability_zone_filter.py → cinder/scheduler/filters/availability_zone_filter.py

@@ -13,7 +13,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-from cinder.openstack.common.scheduler import filters
+from cinder.scheduler import filters
 
 
 class AvailabilityZoneFilter(filters.BaseHostFilter):

cinder/openstack/common/scheduler/filters/capabilities_filter.py → cinder/scheduler/filters/capabilities_filter.py

@@ -17,8 +17,8 @@
 
 import six
 
-from cinder.openstack.common.scheduler import filters
-from cinder.openstack.common.scheduler.filters import extra_specs_ops
+from cinder.scheduler import filters
+from cinder.scheduler.filters import extra_specs_ops
 
 LOG = logging.getLogger(__name__)
 
@@ -27,7 +27,9 @@ class CapabilitiesFilter(filters.BaseHostFilter):
     """HostFilter to work with resource (instance & volume) type records."""
 
     def _satisfies_extra_specs(self, capabilities, resource_type):
-        """Check that the capabilities provided by the services satisfy
+        """Check if capabilities satisfy resource type requirements.
+
+        Check that the capabilities provided by the services satisfy
         the extra specs associated with the resource type.
         """
         extra_specs = resource_type.get('extra_specs', [])

cinder/scheduler/filters/capacity_filter.py

@@ -22,7 +22,7 @@
 from oslo_log import log as logging
 
 from cinder.i18n import _LE, _LW
-from cinder.openstack.common.scheduler import filters
+from cinder.scheduler import filters
 
 
 LOG = logging.getLogger(__name__)

cinder/scheduler/filters/driver_filter.py

@@ -17,8 +17,8 @@
 import six
 
 from cinder.i18n import _LW
-from cinder.openstack.common.scheduler import filters
 from cinder.scheduler.evaluator import evaluator
+from cinder.scheduler import filters
 
 
 LOG = logging.getLogger(__name__)

cinder/openstack/common/scheduler/filters/ignore_attempted_hosts_filter.py → cinder/scheduler/filters/ignore_attempted_hosts_filter.py

@@ -15,7 +15,7 @@
 
 import logging
 
-from cinder.openstack.common.scheduler import filters
+from cinder.scheduler import filters
 
 LOG = logging.getLogger(__name__)
 

cinder/scheduler/filters/instance_locality_filter.py

@@ -19,7 +19,7 @@
 from cinder.compute import nova
 from cinder import exception
 from cinder.i18n import _, _LW
-from cinder.openstack.common.scheduler import filters
+from cinder.scheduler import filters
 from cinder.volume import utils as volume_utils
 
 

cinder/openstack/common/scheduler/filters/json_filter.py → cinder/scheduler/filters/json_filter.py

@@ -18,15 +18,15 @@
 from oslo_serialization import jsonutils
 import six
 
-from cinder.openstack.common.scheduler import filters
+from cinder.scheduler import filters
 
 
 class JsonFilter(filters.BaseHostFilter):
-    """Host Filter to allow simple JSON-based grammar for
-    selecting hosts.
-    """
+    """Host Filter to allow simple JSON-based grammar for selecting hosts."""
     def _op_compare(self, args, op):
-        """Returns True if the specified operator can successfully
+        """Compare first item of args with the rest using specified operator.
+
+        Returns True if the specified operator can successfully
         compare the first item in the args with all the rest. Will
         return False if only one item is in the list.
         """
@@ -88,7 +88,9 @@ def _and(self, args):
     }
 
     def _parse_string(self, string, host_state):
-        """Strings prefixed with $ are capability lookups in the
+        """Parse capability lookup strings.
+
+        Strings prefixed with $ are capability lookups in the
         form '$variable' where 'variable' is an attribute in the
         HostState class.  If $variable is a dictionary, you may
         use: $variable.dictkey
@@ -126,9 +128,7 @@ def _process_filter(self, query, host_state):
         return result
 
     def host_passes(self, host_state, filter_properties):
-        """Return a list of hosts that can fulfill the requirements
-        specified in the query.
-        """
+        """Return a list of hosts that can fulfill query requirements."""
         # TODO(zhiteng) Add description for filter_properties structure
         # and scheduler_hints.
         try:

cinder/scheduler/host_manager.py

@@ -25,11 +25,11 @@
 
 from cinder import context as cinder_context
 from cinder import exception
-from cinder.i18n import _LI, _LW
 from cinder import objects
-from cinder.openstack.common.scheduler import filters
-from cinder.openstack.common.scheduler import weights
 from cinder import utils
+from cinder.i18n import _LI, _LW
+from cinder.scheduler import filters
+from cinder.scheduler import weights
 from cinder.volume import utils as vol_utils
 
 

cinder/scheduler/weights/__init__.py

@@ -0,0 +1,44 @@
+# 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.
+
+"""
+Scheduler host weights
+"""
+
+from cinder.scheduler import base_weight
+
+
+class WeighedHost(base_weight.WeighedObject):
+    def to_dict(self):
+        return {
+            'weight': self.weight,
+            'host': self.obj.host,
+        }
+
+    def __repr__(self):
+        return ("WeighedHost [host: %s, weight: %s]" %
+                (self.obj.host, self.weight))
+
+
+class BaseHostWeigher(base_weight.BaseWeigher):
+    """Base class for host weights."""
+    pass
+
+
+class HostWeightHandler(base_weight.BaseWeightHandler):
+    object_class = WeighedHost
+
+    def __init__(self, namespace):
+        super(HostWeightHandler, self).__init__(BaseHostWeigher, namespace)

cinder/scheduler/weights/capacity.py

@@ -44,7 +44,7 @@
 
 from oslo_config import cfg
 
-from cinder.openstack.common.scheduler import weights
+from cinder.scheduler import weights
 
 
 capacity_weight_opts = [

cinder/scheduler/weights/chance.py

@@ -20,7 +20,7 @@
 
 import random
 
-from cinder.openstack.common.scheduler import weights
+from cinder.scheduler import weights
 
 
 class ChanceWeigher(weights.BaseHostWeigher):

cinder/scheduler/weights/goodness.py

@@ -16,8 +16,8 @@
 import six
 
 from cinder.i18n import _LW
-from cinder.openstack.common.scheduler import weights
 from cinder.scheduler.evaluator import evaluator
+from cinder.scheduler import weights
 
 
 LOG = logging.getLogger(__name__)