remove unnecessary mock for rpc server start

latest oslo.messaging 3.0.0 requires invoking start() first then stop()
can be called, but we've mocked the start() which will hang the process
then finally raise TimeoutException.

This patch removes unnecessary mock for rpc server start(), and bumps
oslo.messaging to align with global requirements.

Change-Id: If22df56a3b3af1e62b9f29fa1be1276d7cf7776d
Closes-Bug: #1519182

aodh/tests/unit/test_notifier.py

@@ -54,12 +54,8 @@ class TestAlarmNotifier(tests_base.BaseTestCase):
             self._fake_generate_request_id))
 
     def test_init_host(self):
-        # If we try to create a real RPC connection, init_host() never
-        # returns. Mock it out so we can establish the service
-        # configuration.
-        with mock.patch.object(self.service.rpc_server, 'start'):
-            self.service.start()
-            self.service.stop()
+        self.service.start()
+        self.service.stop()
 
     def test_notify_alarm(self):
         data = {

requirements.txt

@@ -18,7 +18,7 @@ oslo.service>=0.1.0 # Apache-2.0
 PasteDeploy>=1.5.0
 pbr<2.0,>=0.11
 pecan>=0.8.0
-oslo.messaging>1.17.1,!=2.6.0,!=2.6.1,!=2.8.0 # Apache-2.0
+oslo.messaging>2.6.1,!=2.8.0 # Apache-2.0
 oslo.middleware!=2.0.0,>=1.2.0 # Apache-2.0
 oslo.serialization>=1.4.0 # Apache-2.0
 oslo.utils>=1.9.0 # Apache-2.0