Merge "Do not register notification objects"

doc/ext/versioned_notifications.py

@@ -41,6 +41,7 @@ class VersionedNotificationDirective(Directive):
         return self._build_markup(notifications)
 
     def _collect_notifications(self):
+        base.NovaObjectRegistry.register_notification_objects()
         notifications = []
         ovos = base.NovaObjectRegistry.obj_classes()
         for name, cls in ovos.items():

doc/source/notifications.rst

@@ -106,20 +106,25 @@ How to add a new versioned notification
 
 To support the above contract from the Nova code every versioned notification
 is modeled with oslo versionedobjects. Every versioned notification class
-shall inherit from the `nova.objects.notification.NotificationBase` which
+shall inherit from the `nova.notifications.objects.base.NotificationBase` which
 already defines three mandatory fields of the notification `event_type`,
 `publisher_id` and `priority`. The new notification class shall add a new field
 `payload` with an appropriate payload type. The payload object of the
 notifications shall inherit from the
-`nova.objects.notification.NotificationPayloadBase` class and shall define the
+`nova.objects.notifications.base.NotificationPayloadBase` class and shall
-fields of the payload as versionedobject fields. The base classes are described
+define the fields of the payload as versionedobject fields. The base classes
-in [3]_.
+are described in [3]_.
+
+Please note that the notification objects shall not be registered to the
+NovaObjectRegistry to avoid mixing nova internal objects with the notification
+objects. Instead of that use the register_notification decorator on every
+concrete notification object.
 
 The following code example defines the necessary model classes for a new
 notification `myobject.update`::
 
     @notification.notification_sample('myobject-update.json')
-    @base.NovaObjectRegistry.register
+    @object_base.NovaObjectRegistry.register.register_notification
     class MyObjectNotification(notification.NotificationBase):
         # Version 1.0: Initial version
         VERSION = '1.0'
@@ -129,7 +134,7 @@ notification `myobject.update`::
         }
 
 
-    @base.NovaObjectRegistry.register
+    @object_base.NovaObjectRegistry.register.register_notification
     class MyObjectUpdatePayload(notification.NotificationPayloadBase):
         # Version 1.0: Initial version
         VERSION = '1.0'
@@ -177,7 +182,7 @@ object. For example the service.status notification reuses the existing
 `nova.objects.service.Service` object when defines the notification's payload::
 
     @notification.notification_sample('service-update.json')
-    @base.NovaObjectRegistry.register
+    @object_base.NovaObjectRegistry.register.register_notification
     class ServiceStatusNotification(notification.NotificationBase):
         # Version 1.0: Initial version
         VERSION = '1.0'
@@ -186,7 +191,7 @@ object. For example the service.status notification reuses the existing
             'payload': fields.ObjectField('ServiceStatusPayload')
         }
 
-    @base.NovaObjectRegistry.register
+    @object_base.NovaObjectRegistry.register.register_notification
     class ServiceStatusPayload(notification.NotificationPayloadBase):
         SCHEMA = {
             'host': ('service', 'host'),

nova/notifications/objects/base.py

@@ -12,14 +12,20 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-
 from nova.objects import base
 from nova.objects import fields
 from nova import rpc
 
 
-@base.NovaObjectRegistry.register
+@base.NovaObjectRegistry.register_if(False)
-class EventType(base.NovaObject):
+class NotificationObject(base.NovaObject):
+    """Base class for every notification related versioned object."""
+    # Version 1.0: Initial version
+    VERSION = '1.0'
+
+
+@base.NovaObjectRegistry.register_notification
+class EventType(NotificationObject):
     # Version 1.0: Initial version
     VERSION = '1.0'
 
@@ -37,10 +43,8 @@ class EventType(base.NovaObject):
         return s
 
 
-# Note(gibi): It is explicitly not registered as this class shall not be used
-# directly, it is just a base class for notification payloads.
 @base.NovaObjectRegistry.register_if(False)
-class NotificationPayloadBase(base.NovaObject):
+class NotificationPayloadBase(NotificationObject):
     """Base class for the payload of versioned notifications."""
     # SCHEMA defines how to populate the payload fields. It is a dictionary
     # where every key value pair has the following format:
@@ -81,8 +85,8 @@ class NotificationPayloadBase(base.NovaObject):
         self.populated = True
 
 
-@base.NovaObjectRegistry.register
+@base.NovaObjectRegistry.register_notification
-class NotificationPublisher(base.NovaObject):
+class NotificationPublisher(NotificationObject):
     # Version 1.0: Initial version
     VERSION = '1.0'
 
@@ -96,10 +100,8 @@ class NotificationPublisher(base.NovaObject):
         return cls(host=service.host, binary=service.binary)
 
 
-# Note(gibi): It is explicitly not registered as this class shall not be used
-# directly, it is just a base class for notification.
 @base.NovaObjectRegistry.register_if(False)
-class NotificationBase(base.NovaObject):
+class NotificationBase(NotificationObject):
     """Base class for versioned notifications.
 
     Every subclass shall define a 'payload' field.

nova/notifications/objects/service.py

@@ -14,12 +14,12 @@
 #    under the License.
 
 from nova.notifications.objects import base
-from nova.objects import base as object_base
+from nova.objects import base as nova_base
 from nova.objects import fields
 
 
 @base.notification_sample('service-update.json')
-@object_base.NovaObjectRegistry.register
+@nova_base.NovaObjectRegistry.register_notification
 class ServiceStatusNotification(base.NotificationBase):
     # Version 1.0: Initial version
     VERSION = '1.0'
@@ -29,7 +29,7 @@ class ServiceStatusNotification(base.NotificationBase):
     }
 
 
-@object_base.NovaObjectRegistry.register
+@nova_base.NovaObjectRegistry.register_notification
 class ServiceStatusPayload(base.NotificationPayloadBase):
     SCHEMA = {
         'host': ('service', 'host'),

nova/objects/base.py

@@ -40,6 +40,8 @@ def get_attrname(name):
 
 
 class NovaObjectRegistry(ovoo_base.VersionedObjectRegistry):
+    notification_classes = []
+
     def registration_hook(self, cls, index):
         # NOTE(danms): This is called when an object is registered,
         # and is responsible for maintaining nova.objects.$OBJECT
@@ -53,6 +55,25 @@ class NovaObjectRegistry(ovoo_base.VersionedObjectRegistry):
             if version >= cur_version:
                 setattr(objects, cls.obj_name(), cls)
 
+    @classmethod
+    def register_notification(cls, notification_cls):
+        """Register a class as notification.
+        Use only to register concrete notification or payload classes,
+        do not register base classes intended for inheritance only.
+        """
+        cls.register_if(False)(notification_cls)
+        cls.notification_classes.append(notification_cls)
+        return notification_cls
+
+    @classmethod
+    def register_notification_objects(cls):
+        """Register previously decorated notification as normal ovos.
+        This is not intended for production use but only for testing and
+        document generation purposes.
+        """
+        for notification_cls in cls.notification_classes:
+            cls.register(notification_cls)
+
 
 remotable_classmethod = ovoo_base.remotable_classmethod
 remotable = ovoo_base.remotable

nova/tests/unit/objects/test_objects.py

@@ -1209,6 +1209,11 @@ object_data = {
 
 
 class TestObjectVersions(test.NoDBTestCase):
+
+    def setUp(self):
+        super(test.NoDBTestCase, self).setUp()
+        base.NovaObjectRegistry.register_notification_objects()
+
     def test_versions(self):
         checker = fixture.ObjectVersionChecker(
             base.NovaObjectRegistry.obj_classes())