docs: Document StatefulSet should be applied last (#694)

* docs: Document StatefulSet should be applied last

* Improve message

* Add generation assertion to smoke test

Author: sbernauer

rust/operator-binary/src/superset_controller.rs

@@ -467,6 +467,10 @@ pub async fn reconcile_superset(
             .with_context(|_| ApplyRoleGroupConfigSnafu {
                 rolegroup: rolegroup.clone(),
             })?;
+
+        // Note: The StatefulSet needs to be applied after all ConfigMaps and Secrets it mounts
+        // to prevent unnecessary Pod restarts.
+        // See https://github.com/stackabletech/commons-operator/issues/111 for details.
         ss_cond_builder.add(
             cluster_resources
                 .add(client, rg_statefulset.clone())

tests/templates/kuttl/smoke/30-assert.yaml

@@ -11,6 +11,7 @@ apiVersion: apps/v1
 kind: StatefulSet
 metadata:
   name: superset-node-default
+  generation: 1 # There should be no unneeded Pod restarts
 spec:
   template:
     spec: