Allow Notifier to have multiple topics

Looks like there is a disconnect between the __init__
parameter 'topic' in Notifier and what we need when
we look up a driver. We should allow multiple topics
to be specified as a new topics parameter and pass
that along directly.

Change-Id: Id89957411aa219cff92fafec2f448c81cb57b3ca

oslo_messaging/notify/notifier.py

@@ -19,6 +19,7 @@ import abc
 import logging
 import uuid
 
+from debtcollector import renames
 from oslo_config import cfg
 from oslo_utils import timeutils
 import six
@@ -142,9 +143,14 @@ class Notifier(object):
         notifier.info(ctxt, event_type, payload)
     """
 
+    @renames.renamed_kwarg('topic', 'topics',
+                           message="Please use topics instead of topic",
+                           version='4.5.0',
+                           removal_version='5.0.0')
     def __init__(self, transport, publisher_id=None,
                  driver=None, topic=None,
-                 serializer=None, retry=None):
+                 serializer=None, retry=None,
+                 topics=None):
         """Construct a Notifier object.
 
         :param transport: the transport to use for sending messages
@@ -163,6 +169,8 @@ class Notifier(object):
                       0 means no retry
                       N means N retries
         :type retry: int
+        :param topics: the topics which to send messages on
+        :type topic: list of strings
         """
         conf = transport.conf
         conf.register_opts(_notifier_opts,
@@ -175,8 +183,12 @@ class Notifier(object):
         self._driver_names = ([driver] if driver is not None else
                               conf.oslo_messaging_notifications.driver)
 
-        self._topics = ([topic] if topic is not None else
-                        conf.oslo_messaging_notifications.topics)
+        if topics is not None:
+            self._topics = topics
+        elif topic is not None:
+            self._topics = [topic]
+        else:
+            self._topics = conf.oslo_messaging_notifications.topics
         self._serializer = serializer or msg_serializer.NoOpSerializer()
 
         self._driver_mgr = named.NamedExtensionManager(

oslo_messaging/tests/notify/test_notifier.py

@@ -266,6 +266,31 @@ class TestSerializer(test_utils.BaseTestCase):
                          _impl_test.NOTIFICATIONS)
 
 
+class TestNotifierTopics(test_utils.BaseTestCase):
+
+    def test_topics_from_config(self):
+        self.config(driver=['log'],
+                    group='oslo_messaging_notifications')
+        self.config(topics=['topic1', 'topic2'],
+                    group='oslo_messaging_notifications')
+        transport = _FakeTransport(self.conf)
+
+        notifier = oslo_messaging.Notifier(transport, 'test.localhost')
+        self.assertEqual(['topic1', 'topic2'], notifier._topics)
+
+    def test_topics_from_kwargs(self):
+        self.config(driver=['log'],
+                    group='oslo_messaging_notifications')
+        transport = _FakeTransport(self.conf)
+
+        notifier = oslo_messaging.Notifier(transport, 'test.localhost',
+                                           topic='topic1')
+        self.assertEqual(['topic1'], notifier._topics)
+        notifier = oslo_messaging.Notifier(transport, 'test.localhost',
+                                           topics=['topic1', 'topic2'])
+        self.assertEqual(['topic1', 'topic2'], notifier._topics)
+
+
 class TestLogNotifier(test_utils.BaseTestCase):
 
     @mock.patch('oslo_utils.timeutils.utcnow')