Address nits in server group policy series

Change-Id: I126b51892056e3241640bbf05acf16d7f72b4329

nova/db/sqlalchemy/api_models.py

@@ -447,7 +447,7 @@ class InstanceGroup(API_BASE):
 
     @property
     def policy(self):
-        if len(self._policies) not in (0, 1):
+        if len(self._policies) > 1:
             msg = ("More than one policy (%(policies)s) is associated with "
                    "group %(group_name)s, only the first one in the list "
                    "would be returned.")

nova/scheduler/filters/affinity_filter.py

@@ -120,7 +120,7 @@ class _GroupAntiAffinityFilter(filters.BaseHostFilter):
                   {'group_uuid': group_uuid,
                    'host': host_state.host,
                    'max_server': max_server_per_host})
-        # Note(yikun): If the number of servers from same group on this host
+        # NOTE(yikun): If the number of servers from same group on this host
         # is less than the max_server_per_host, this filter will accept the
         # given host. In the default case(max_server_per_host=1), this filter
         # will accept the given host if there are 0 servers from the group

nova/tests/unit/scheduler/filters/test_affinity_filters.py

@@ -149,7 +149,7 @@ class TestGroupAffinityFilter(test.NoDBTestCase):
             policy='affinity'))
         self.assertTrue(filt_cls.host_passes(host, spec_obj))
         spec_obj = objects.RequestSpec(instance_group=objects.InstanceGroup(
-            policy=policy, members=[], rules={}), instance_uuid=uuids.fake)
+            policy=policy, members=[]), instance_uuid=uuids.fake)
         spec_obj.instance_group.hosts = []
         self.assertTrue(filt_cls.host_passes(host, spec_obj))
         spec_obj.instance_group.hosts = ['host2']

releasenotes/notes/complex-anti-affinity-policies-dcf4719e859093be.yaml

@@ -1,11 +1,11 @@
 ---
 features:
   - |
-    Enable users to define the policy rules on server group policy to meet
+    Microversion 2.64 is added and enables users to define rules on server
-    more advanced policy requirement. This microversion 2.64 brings the
+    group policy to meet more advanced policy requirements. This microversion
-    following changes in server group APIs:
+    brings the following changes in server group APIs:
 
-    * Add  ``policy`` and ``rules`` fields in the request of POST
+    * Add ``policy`` and ``rules`` fields in the request of POST
       ``/os-server-groups``. The ``policy`` represents the name of policy. The
       ``rules`` field, which is a dict, can be applied to the policy, which
       currently only supports ``max_server_per_host`` for ``anti-affinity``

releasenotes/notes/use-new-style-policy-in-notifications-3c6eefbb56224be2.yaml

@@ -5,6 +5,6 @@ features:
     The new style ``policy`` field has been added to ``ServerGroupPayload``.
     The ``server_group.create``, ``server_group.delete`` and
     ``server_group.add_member`` versioned notifications will be updated to
-    include the new ``policy`` and ``rules``field. The ``policies`` field is
+    include the new ``policy`` and ``rules`` field. The ``policies`` field is
     deprecated for removal but still put into the notification payload for
     backward compatibility.