Do not validate driver on changing non-driver fields

This prevents setting maintenance on nodes with a broken driver.

Change-Id: Ibd94d9d8ad5467f8430f77673a34507feb83da84

ironic/conductor/manager.py

@@ -209,6 +209,7 @@ class ConductorManager(base_manager.BaseConductorManager):
                    "updated unless it is in one of allowed "
                    "(%(allowed)s) states or in maintenance mode.")
         updating_driver = 'driver' in delta
+        check_interfaces = updating_driver
         for iface in drivers_base.ALL_INTERFACES:
             interface_field = '%s_interface' % iface
             if interface_field not in delta:
@@ -224,7 +225,10 @@ class ConductorManager(base_manager.BaseConductorManager):
                               'allowed': ', '.join(allowed_update_states),
                               'field': interface_field})
 
-        driver_factory.check_and_update_node_interfaces(node_obj)
+            check_interfaces = True
+
+        if check_interfaces:
+            driver_factory.check_and_update_node_interfaces(node_obj)
 
         # NOTE(dtantsur): if we're updating the driver from an invalid value,
         # loading the old driver may be impossible. Since we only need to

ironic/tests/unit/conductor/test_manager.py

@@ -960,6 +960,51 @@ class UpdateNodeTestCase(mgr_utils.ServiceSetUpMixin, db_base.DbTestCase):
         self.assertIsNone(node.instance_uuid)
         self.assertIsNone(node.allocation_id)
 
+    def test_update_node_maintenance_with_broken_interface(self):
+        # Updates of non-driver fields are possible with a broken driver
+        node = obj_utils.create_test_node(self.context, driver='fake-hardware',
+                                          power_interface='foobar',
+                                          extra={'test': 'one'})
+
+        node.maintenance = True
+        res = self.service.update_node(self.context, node)
+        self.assertTrue(res.maintenance)
+
+        node.refresh()
+        self.assertTrue(node.maintenance)
+        self.assertEqual('foobar', node.power_interface)
+
+    def test_update_node_interface_field_with_broken_interface(self):
+        # Updates of driver fields are NOT possible with a broken driver,
+        # unless they're fixing the breakage.
+        node = obj_utils.create_test_node(self.context, driver='fake-hardware',
+                                          power_interface='foobar',
+                                          deploy_interface='fake',
+                                          extra={'test': 'one'})
+
+        node.deploy_interface = 'iscsi'
+        exc = self.assertRaises(messaging.rpc.ExpectedException,
+                                self.service.update_node,
+                                self.context, node)
+        self.assertEqual(exception.InterfaceNotFoundInEntrypoint,
+                         exc.exc_info[0])
+
+        node.refresh()
+        self.assertEqual('foobar', node.power_interface)
+        self.assertEqual('fake', node.deploy_interface)
+
+    def test_update_node_fix_broken_interface(self):
+        # Updates of non-driver fields are possible with a broken driver
+        node = obj_utils.create_test_node(self.context, driver='fake-hardware',
+                                          power_interface='foobar',
+                                          extra={'test': 'one'})
+
+        node.power_interface = 'fake'
+        self.service.update_node(self.context, node)
+
+        node.refresh()
+        self.assertEqual('fake', node.power_interface)
+
 
 @mgr_utils.mock_record_keepalive
 class VendorPassthruTestCase(mgr_utils.ServiceSetUpMixin, db_base.DbTestCase):

releasenotes/notes/driver-maintenance-0945c2939fa4e917.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - |
+    Fixes updating driver fields for nodes with a broken driver. This is
+    required to be able to set maintenance for such nodes.