Ensure anti affinity scheduling works

The query for the group in the system_metadata would not correctly
filter the instances with the groups.

In addition to this change 4a03071db2
ensured that the scheduling filter was only run once.
In cases when provisioning fails and rescheduling
takes place the filter must be invoked (if it is in the filter tool
chain).

Fixes bug: 1218878
Fixes bug: 1206502

Change-Id: I623c73635c36ffa038ae01476a25ba0c0863e536

nova/db/sqlalchemy/api.py

@@ -252,7 +252,7 @@ def exact_filter(query, model, filters, legal_keys):
         # OK, filtering on this key; what value do we search for?
         value = filters.pop(key)
 
-        if key == 'metadata':
+        if key == 'metadata' or key == 'system_metadata':
             column_attr = getattr(model, key)
             if isinstance(value, list):
                 for item in value:
@@ -1804,7 +1804,7 @@ def instance_get_all_by_filters(context, filters, sort_key, sort_dir,
 
         ['project_id', 'user_id', 'image_ref',
          'vm_state', 'instance_type_id', 'uuid',
-         'metadata', 'host']
+         'metadata', 'host', 'system_metadata']
 
 
     A third type of filter (also using exact matching), filters
@@ -1892,7 +1892,8 @@ def instance_get_all_by_filters(context, filters, sort_key, sort_dir,
     # For other filters that don't match this, we will do regexp matching
     exact_match_filter_names = ['project_id', 'user_id', 'image_ref',
                                 'vm_state', 'instance_type_id', 'uuid',
-                                'metadata', 'host', 'task_state']
+                                'metadata', 'host', 'task_state',
+                                'system_metadata']
 
     # Filter the query
     query_prefix = exact_filter(query_prefix, models.Instance,

nova/scheduler/driver.py

@@ -121,7 +121,7 @@ class Scheduler(object):
 
         # The system_metadata 'group' will be filtered
         members = db.instance_get_all_by_filters(context,
-                {'deleted': False, 'group': group})
+                {'deleted': False, 'system_metadata': {'group': group}})
         return [member['host']
                 for member in members
                 if member.get('host') is not None]

nova/scheduler/filters/affinity_filter.py

@@ -103,10 +103,6 @@ class GroupAntiAffinityFilter(AffinityFilter):
     hosts.
     """
 
-    # The hosts the instances in the group are running on doesn't change
-    # within a request
-    run_filter_once_per_request = True
-
     def host_passes(self, host_state, filter_properties):
         group_hosts = filter_properties.get('group_hosts') or []
         LOG.debug(_("Group anti affinity: check if %(host)s not "

nova/tests/db/test_db_api.py

@@ -1478,6 +1478,14 @@ class InstanceTestCase(test.TestCase, ModelsObjectComparatorMixin):
                                                 {'metadata': {'foo': 'bar'}})
         self._assertEqualListsOfInstances([instance], result)
 
+    def test_instance_get_all_by_filters_system_metadata(self):
+        instance = self.create_instance_with_args(
+                system_metadata={'foo': 'bar'})
+        self.create_instance_with_args()
+        result = db.instance_get_all_by_filters(self.ctxt,
+                {'system_metadata': {'foo': 'bar'}})
+        self._assertEqualListsOfInstances([instance], result)
+
     def test_instance_get_all_by_filters_unicode_value(self):
         instance = self.create_instance_with_args(display_name=u'test♥')
         result = db.instance_get_all_by_filters(self.ctxt,