V3 Pause: treat case when driver does not implement the operation

Some virt drivers may not support this operation.

Change-Id: I21a3fbb6e41e4a32810fd8c76f0fabb7aeff9244

nova/api/openstack/compute/plugins/v3/pause_server.py

@@ -21,6 +21,7 @@ from nova.api.openstack import extensions
 from nova.api.openstack import wsgi
 from nova import compute
 from nova import exception
+from nova.openstack.common.gettextutils import _
 from nova.openstack.common import log as logging
 
 LOG = logging.getLogger(__name__)
@@ -37,7 +38,7 @@ class PauseServerController(wsgi.Controller):
         super(PauseServerController, self).__init__(*args, **kwargs)
         self.compute_api = compute.API()
 
-    @extensions.expected_errors((404, 409))
+    @extensions.expected_errors((404, 409, 501))
     @wsgi.action('pause')
     def _pause(self, req, id, body):
         """Permit Admins to pause the server."""
@@ -54,9 +55,12 @@ class PauseServerController(wsgi.Controller):
                     'pause')
         except exception.InstanceNotFound as e:
             raise exc.HTTPNotFound(explanation=e.format_message())
+        except NotImplementedError:
+            msg = _("Virt driver does not implement pause function.")
+            raise exc.HTTPNotImplemented(explanation=msg)
         return webob.Response(status_int=202)
 
-    @extensions.expected_errors((404, 409))
+    @extensions.expected_errors((404, 409, 501))
     @wsgi.action('unpause')
     def _unpause(self, req, id, body):
         """Permit Admins to unpause the server."""
@@ -73,6 +77,9 @@ class PauseServerController(wsgi.Controller):
                     'unpause')
         except exception.InstanceNotFound as e:
             raise exc.HTTPNotFound(explanation=e.format_message())
+        except NotImplementedError:
+            msg = _("Virt driver does not implement pause function.")
+            raise exc.HTTPNotImplemented(explanation=msg)
         return webob.Response(status_int=202)
 
 

nova/tests/api/openstack/compute/plugins/v3/admin_only_action_common.py

@@ -90,6 +90,28 @@ class CommonMixin(object):
         self.mox.VerifyAll()
         self.mox.UnsetStubs()
 
+    def _test_not_implemented_state(self, action, method=None):
+        if method is None:
+            method = action
+
+        instance = self._stub_instance_get()
+        body = {}
+        compute_api_args_map = {}
+        args, kwargs = compute_api_args_map.get(action, ((), {}))
+        getattr(self.compute_api, method)(self.context, instance,
+                                          *args, **kwargs).AndRaise(
+                NotImplementedError())
+
+        self.mox.ReplayAll()
+
+        res = self._make_request('/servers/%s/action' % instance.uuid,
+                                 {action: body})
+        self.assertEqual(501, res.status_int)
+        # Do these here instead of tearDown because this method is called
+        # more than once for the same test case
+        self.mox.VerifyAll()
+        self.mox.UnsetStubs()
+
     def _test_invalid_state(self, action, method=None, body_map=None,
                             compute_api_args_map=None):
         if method is None:

nova/tests/api/openstack/compute/plugins/v3/test_pause_server.py

@@ -38,6 +38,13 @@ class PauseServerTests(admin_only_action_common.CommonTests):
     def test_pause_unpause(self):
         self._test_actions(['pause', 'unpause'])
 
+    def test_actions_raise_on_not_implemented(self):
+        for action in ['pause', 'unpause']:
+            self.mox.StubOutWithMock(self.compute_api, action)
+            self._test_not_implemented_state(action)
+            # Re-mock this.
+            self.mox.StubOutWithMock(self.compute_api, 'get')
+
     def test_pause_unpause_with_non_existed_instance(self):
         self._test_actions_with_non_existed_instance(['pause', 'unpause'])