Merge "Prevent compute crash on discovery failure"

nova/cmd/status.py

@@ -216,6 +216,9 @@ class UpgradeCommands(object):
         except ks_exc.EndpointNotFound:
             msg = _('Placement API endpoint not found.')
             return UpgradeCheckResult(UpgradeCheckCode.FAILURE, msg)
+        except ks_exc.DiscoveryFailure:
+            msg = _('Discovery for placement API URI failed.')
+            return UpgradeCheckResult(UpgradeCheckCode.FAILURE, msg)
         except ks_exc.NotFound:
             msg = _('Placement API does not seem to be running.')
             return UpgradeCheckResult(UpgradeCheckCode.FAILURE, msg)

nova/scheduler/client/report.py

@@ -72,6 +72,13 @@ def safe_connect(f):
                     'Placement is optional in Newton, but required '
                     'in Ocata. Please enable the placement service '
                     'before upgrading.'))
+        except ks_exc.DiscoveryFailure:
+            # TODO(_gryf): Looks like DiscoveryFailure is not the only missing
+            # exception here. In Pike we should take care about keystoneauth1
+            # failures handling globally.
+            warn_limit(self,
+                       _LW('Discovering suitable URL for placement API '
+                           'failed.'))
         except ks_exc.ConnectFailure:
             msg = _LW('Placement API service is not responding.')
             LOG.warning(msg)

nova/tests/unit/cmd/test_status.py

@@ -148,6 +148,19 @@ class TestPlacementCheck(test.NoDBTestCase):
         self.assertEqual(status.UpgradeCheckCode.FAILURE, res.code)
         self.assertIn('Placement API endpoint not found', res.details)
 
+    @mock.patch.object(status.UpgradeCommands, "_placement_get")
+    def test_discovery_failure(self, get):
+        """Test failure when discovery for placement URL failed.
+
+        Replicate in devstack: start devstack with placement
+        engine, create valid placement service user and specify it
+        in auth section of [placement] in nova.conf. Stop keystone service.
+        """
+        get.side_effect = ks_exc.DiscoveryFailure()
+        res = self.cmd._check_placement()
+        self.assertEqual(status.UpgradeCheckCode.FAILURE, res.code)
+        self.assertIn('Discovery for placement API URI failed.', res.details)
+
     @mock.patch.object(status.UpgradeCommands, "_placement_get")
     def test_down_endpoint(self, get):
         """Test failure when endpoint is down.

nova/tests/unit/scheduler/client/test_report.py

@@ -114,6 +114,21 @@ class SafeConnectedTestCase(test.NoDBTestCase):
         mock_log.warning.assert_has_calls([mock.call('warning'),
                                            mock.call('warning')])
 
+    @mock.patch('keystoneauth1.session.Session.request')
+    def test_failed_discovery(self, req):
+        """Test DiscoveryFailure behavior.
+
+        Failed discovery should not blow up.
+        """
+        req.side_effect = ks_exc.DiscoveryFailure()
+        self.client._get_resource_provider("fake")
+
+        # reset the call count to demonstrate that future calls still
+        # work
+        req.reset_mock()
+        self.client._get_resource_provider("fake")
+        self.assertTrue(req.called)
+
 
 class TestConstructor(test.NoDBTestCase):
     @mock.patch('keystoneauth1.session.Session')