kuberntes: Disable the scale_manager for scale down

Due to bug #1746510, the kubernetes scale manager needs to be
disabled to not break the scale down command completely. Note, that when
magnum scales down the cluster will pick the nodes to scale randomly.

Related-Bug: #1746510
Change-Id: I8c3505ec6d155323288217e0c8ea54adabdff1c3

magnum/drivers/k8s_coreos_v1/driver.py

@@ -13,7 +13,6 @@
 # under the License.
 
 from magnum.drivers.common import k8s_monitor
-from magnum.drivers.common.k8s_scale_manager import K8sScaleManager
 from magnum.drivers.heat import driver
 from magnum.drivers.k8s_coreos_v1 import template_def
 
@@ -35,4 +34,7 @@ class Driver(driver.HeatDriver):
         return k8s_monitor.K8sMonitor(context, cluster)
 
     def get_scale_manager(self, context, osclient, cluster):
-        return K8sScaleManager(context, osclient, cluster)
+        # FIXME: Until the kubernetes client is fixed, remove
+        # the scale_manager.
+        # https://bugs.launchpad.net/magnum/+bug/1746510
+        return None

magnum/drivers/k8s_fedora_atomic_v1/driver.py

@@ -13,7 +13,6 @@
 # under the License.
 
 from magnum.drivers.common import k8s_monitor
-from magnum.drivers.common.k8s_scale_manager import K8sScaleManager
 from magnum.drivers.heat import driver
 from magnum.drivers.k8s_fedora_atomic_v1 import template_def
 
@@ -35,4 +34,7 @@ class Driver(driver.HeatDriver):
         return k8s_monitor.K8sMonitor(context, cluster)
 
     def get_scale_manager(self, context, osclient, cluster):
-        return K8sScaleManager(context, osclient, cluster)
+        # FIXME: Until the kubernetes client is fixed, remove
+        # the scale_manager.
+        # https://bugs.launchpad.net/magnum/+bug/1746510
+        return None

magnum/drivers/k8s_fedora_ironic_v1/driver.py

@@ -13,7 +13,6 @@
 # under the License.
 
 from magnum.drivers.common import k8s_monitor
-from magnum.drivers.common.k8s_scale_manager import K8sScaleManager
 from magnum.drivers.heat import driver
 from magnum.drivers.k8s_fedora_ironic_v1 import template_def
 
@@ -35,4 +34,7 @@ class Driver(driver.HeatDriver):
         return k8s_monitor.K8sMonitor(context, cluster)
 
     def get_scale_manager(self, context, osclient, cluster):
-        return K8sScaleManager(context, osclient, cluster)
+        # FIXME: Until the kubernetes client is fixed, remove
+        # the scale_manager.
+        # https://bugs.launchpad.net/magnum/+bug/1746510
+        return None

releasenotes/notes/broken-kuberenetes-client-d2d1da6029825208.yaml

@@ -10,6 +10,10 @@ issues:
     task uses the kubernetes client for kubernetes clusters and it crashes
     the sync_cluster_status and send_cluster_metrics tasks.
     https://bugs.launchpad.net/magnum/+bug/1746510
+    Additionally, the kubernetes scale manager needs to be disabled
+    to not break the scale down command completely. Note, that when magnum
+    scales down the cluster will pick the nodes to scale randomly.
+
 upgrade:
   - |
     In magnum configuration, in [drivers] set send_cluster_metrics = False to