Implement update bay node_count

It is implemented by updating the Heat stack with the new node_count

Partially implements: blueprint update-node-count

Change-Id: I2c331043bb6e6fce14fc82932dcd9c3677448598

magnum/api/controllers/v1/bay.py

@@ -278,8 +278,8 @@ class BaysController(rest.RestController):
             if rpc_bay[field] != patch_val:
                 rpc_bay[field] = patch_val
 
-        rpc_bay.save()
-        return Bay.convert_with_links(rpc_bay)
+        res_bay = pecan.request.rpcapi.bay_update(rpc_bay)
+        return Bay.convert_with_links(res_bay)
 
     @wsme_pecan.wsexpose(None, types.uuid, status_code=204)
     def delete(self, bay_uuid):

magnum/conductor/api.py

@@ -59,6 +59,9 @@ class API(rpc_service.API):
     def bay_show(self, context, uuid):
         return objects.Bay.get_by_uuid(context, uuid)
 
+    def bay_update(self, bay):
+        return self._call('bay_update', bay=bay)
+
     # Service Operations
 
     def service_create(self, service):

magnum/conductor/handlers/bay_k8s_heat.py

@@ -17,6 +17,7 @@ from heatclient import exc
 from oslo_config import cfg
 
 from magnum.common import clients
+from magnum.common import exception
 from magnum.common import short_id
 from magnum import objects
 from magnum.openstack.common._i18n import _
@@ -87,6 +88,20 @@ def _create_stack(context, osc, bay):
     return created_stack
 
 
+def _update_stack(context, osc, bay):
+    bay_definition = _extract_bay_definition(context, bay)
+
+    tpl_files, template = template_utils.get_template_contents(
+                                        cfg.CONF.k8s_heat.template_path)
+    fields = {
+        'parameters': bay_definition,
+        'template': template,
+        'files': dict(list(tpl_files.items()))
+    }
+
+    return osc.heat().stacks.update(bay.stack_id, **fields)
+
+
 def _parse_stack_outputs(outputs):
     parsed_outputs = {}
 
@@ -122,6 +137,30 @@ class Handler(object):
 
         return bay
 
+    def bay_update(self, context, bay):
+        LOG.debug('k8s_heat bay_update')
+
+        osc = clients.OpenStackClients(context)
+        stack = osc.heat().stacks.get(bay.stack_id)
+        if (stack.stack_status != 'CREATE_COMPLETE' and
+            stack.stack_status != 'UPDATE_COMPLETE'):
+            raise exception.MagnumException(_(
+                "Cannot update stack with status: %s") % stack.stack_status)
+
+        delta = bay.obj_what_changed()
+        if 'node_count' in delta:
+            delta.remove('node_count')
+
+            _update_stack(context, osc, bay)
+            self._poll_and_check(osc, bay)
+
+        if delta:
+            raise exception.InvalidParameterValue(err=(
+                "cannot change bay property(ies) %s." % ", ".join(delta)))
+
+        bay.save()
+        return bay
+
     def bay_delete(self, context, uuid):
         LOG.debug('k8s_heat bay_delete')
         osc = clients.OpenStackClients(context)
@@ -156,7 +195,8 @@ class Handler(object):
         def poll_and_check():
             stack = osc.heat().stacks.get(bay.stack_id)
             attempts['count'] += 1
-            if stack.stack_status == 'CREATE_COMPLETE':
+            if (stack.stack_status == 'CREATE_COMPLETE' or
+                stack.stack_status == 'UPDATE_COMPLETE'):
                 parsed_outputs = _parse_stack_outputs(stack.outputs)
                 master_address = parsed_outputs["kube_master"]
                 minion_address = parsed_outputs["kube_minions_external"]

magnum/tests/api/controllers/v1/test_bay.py

@@ -129,6 +129,14 @@ class TestPatch(api_base.FunctionalTest):
         self.bay = obj_utils.create_test_bay(self.context,
                                              name='bay_example_A',
                                              node_count=3)
+        p = mock.patch.object(rpcapi.API, 'bay_update')
+        self.mock_bay_update = p.start()
+        self.mock_bay_update.side_effect = self._simulate_rpc_bay_update
+        self.addCleanup(p.stop)
+
+    def _simulate_rpc_bay_update(self, bay):
+        bay.save()
+        return bay
 
     @mock.patch('oslo.utils.timeutils.utcnow')
     def test_replace_ok(self, mock_utcnow):

magnum/tests/conductor/handlers/test_bay_k8s_heat.py

@@ -230,3 +230,34 @@ class TestBayK8sHeat(base.TestCase):
             'files': dict(exptected_files)
         }
         mock_heat_client.stacks.create.assert_called_once_with(**expected_args)
+
+    @patch('heatclient.common.template_utils.get_template_contents')
+    @patch('magnum.conductor.handlers.bay_k8s_heat._extract_bay_definition')
+    def test_update_stack(self,
+                          mock_extract_bay_definition,
+                          mock_get_template_contents):
+
+        mock_stack_id = 'xx-xx-xx-xx'
+        expected_template_contents = 'template_contents'
+        exptected_files = []
+
+        mock_tpl_files = mock.MagicMock()
+        mock_tpl_files.items.return_value = exptected_files
+        mock_get_template_contents.return_value = [
+            mock_tpl_files, expected_template_contents]
+        mock_extract_bay_definition.return_value = {}
+        mock_heat_client = mock.MagicMock()
+        mock_osc = mock.MagicMock()
+        mock_osc.heat.return_value = mock_heat_client
+        mock_bay = mock.MagicMock()
+        mock_bay.stack_id = mock_stack_id
+
+        bay_k8s_heat._update_stack({}, mock_osc, mock_bay)
+
+        expected_args = {
+            'parameters': {},
+            'template': expected_template_contents,
+            'files': dict(exptected_files)
+        }
+        mock_heat_client.stacks.update.assert_called_once_with(mock_stack_id,
+                                                               **expected_args)