Merge "Adds default fall-through to the multi scheduler. Fixes bug 1009681"

Authors

@@ -49,6 +49,7 @@ Daniel P. Berrange <berrange@redhat.com>
 Dave Lapsley <dlapsley@nicira.com>
 Dave Walker <Dave.Walker@canonical.com>
 David Pravec <David.Pravec@danix.org>
+David Scannell <dscannell@gridcentric.com>
 David Shrewsbury <shrewsbury.dave@gmail.com>
 David Subiros <david.perez5@hp.com>
 Dean Troyer <dtroyer@gmail.com>

nova/scheduler/multi.py

@@ -35,6 +35,9 @@ multi_scheduler_opts = [
     cfg.StrOpt('volume_scheduler_driver',
                default='nova.scheduler.chance.ChanceScheduler',
                help='Driver to use for scheduling volume calls'),
+    cfg.StrOpt('default_scheduler_driver',
+               default='nova.scheduler.chance.ChanceScheduler',
+               help='Default driver to use for scheduling calls'),
     ]
 
 FLAGS = flags.FLAGS
@@ -60,9 +63,12 @@ class MultiScheduler(driver.Scheduler):
                 FLAGS.compute_scheduler_driver)
         volume_driver = importutils.import_object(
                 FLAGS.volume_scheduler_driver)
+        default_driver = importutils.import_object(
+                FLAGS.default_scheduler_driver)
 
         self.drivers = {'compute': compute_driver,
-                        'volume': volume_driver}
+                        'volume': volume_driver,
+                        'default': default_driver}
 
     def __getattr__(self, key):
         if not key.startswith('schedule_'):
@@ -73,7 +79,8 @@ class MultiScheduler(driver.Scheduler):
         return getattr(self.drivers[_METHOD_MAP[method]], key)
 
     def schedule(self, context, topic, method, *_args, **_kwargs):
-        return self.drivers[topic].schedule(context, topic,
+        driver = self.drivers.get(topic, self.drivers['default'])
+        return driver.schedule(context, topic,
                 method, *_args, **_kwargs)
 
     def schedule_run_instance(self, *args, **kwargs):

nova/tests/scheduler/test_multi_scheduler.py

@@ -56,6 +56,17 @@ class FakeVolumeScheduler(driver.Scheduler):
         pass
 
 
+class FakeDefaultScheduler(driver.Scheduler):
+    is_fake_default = True
+
+    def __init__(self):
+        super(FakeDefaultScheduler, self).__init__()
+        self.is_update_caps_called = False
+
+    def schedule(self, *args, **kwargs):
+        pass
+
+
 class MultiDriverTestCase(test_scheduler.SchedulerTestCase):
     """Test case for multi driver"""
 
@@ -66,15 +77,18 @@ class MultiDriverTestCase(test_scheduler.SchedulerTestCase):
         base_name = 'nova.tests.scheduler.test_multi_scheduler.%s'
         compute_cls_name = base_name % 'FakeComputeScheduler'
         volume_cls_name = base_name % 'FakeVolumeScheduler'
+        default_cls_name = base_name % 'FakeDefaultScheduler'
         self.flags(compute_scheduler_driver=compute_cls_name,
-                volume_scheduler_driver=volume_cls_name)
+                volume_scheduler_driver=volume_cls_name,
+                default_scheduler_driver=default_cls_name)
         self._manager = multi.MultiScheduler()
 
     def test_drivers_inited(self):
         mgr = self._manager
-        self.assertEqual(len(mgr.drivers), 2)
+        self.assertEqual(len(mgr.drivers), 3)
         self.assertTrue(mgr.drivers['compute'].is_fake_compute)
         self.assertTrue(mgr.drivers['volume'].is_fake_volume)
+        self.assertTrue(mgr.drivers['default'].is_fake_default)
 
     def test_proxy_calls(self):
         mgr = self._manager
@@ -96,6 +110,7 @@ class MultiDriverTestCase(test_scheduler.SchedulerTestCase):
 
         self.mox.StubOutWithMock(mgr.drivers['compute'], 'schedule')
         self.mox.StubOutWithMock(mgr.drivers['volume'], 'schedule')
+        self.mox.StubOutWithMock(mgr.drivers['default'], 'schedule')
 
         ctxt = 'fake_context'
         method = 'fake_method'
@@ -107,10 +122,13 @@ class MultiDriverTestCase(test_scheduler.SchedulerTestCase):
                 *fake_args, **fake_kwargs)
         mgr.drivers['volume'].schedule(ctxt, 'volume', method,
                 *fake_args, **fake_kwargs)
+        mgr.drivers['default'].schedule(ctxt, 'random_topic', method,
+                *fake_args, **fake_kwargs)
 
         self.mox.ReplayAll()
         mgr.schedule(ctxt, 'compute', method, *fake_args, **fake_kwargs)
         mgr.schedule(ctxt, 'volume', method, *fake_args, **fake_kwargs)
+        mgr.schedule(ctxt, 'random_topic', method, *fake_args, **fake_kwargs)
 
     def test_update_service_capabilities(self):
         def fake_update_service_capabilities(self, service, host, caps):