K8ssandraCluster Spec is modified the by operator

[burmanm]

What happened?
I noticed K8ssandraCluster (and CassandraDatacenter) would change generation after k8ssandra-operator is started. What happened is that k8ssandra-operator would modify the superuserSecretRef field in the K8ssandraCluster in reconcileSuperuserSecret() method.

This causes external tools that check the consistency of K8ssandraCluster to fail, since they then modify it back and the loop starts.

There's also the injection method, which causes the StatefulSets generated by cass-operator to have 3 generations on each update and causing 2 unnecessary rolling restarts in this case. First having the correct annotations, next one removing them and third one re-adding them. This is due to the reconciling going nuts with the Spec generation changes.

Did you expect to see something different?

This change should not happen, the superuserSecretName should be modified in the CassandraDatacenter object by k8ssandra-operator, not to K8ssandraCluster.Spec.Cassandra

How to reproduce it (as minimally and precisely as possible):

Environment

• K8ssandra Operator version:

  Insert image tag or Git SHA here

• Kubernetes version information:

  kubectl version

• Kubernetes cluster kind:

  insert how you created your cluster: kops, bootkube, etc.

• Manifests:

insert manifests relevant to the issue

• K8ssandra Operator Logs:

insert K8ssandra Operator logs relevant to the issue here

Anything else we need to know?:

[burmanm]

Another thing to add is verifying in the e2e tests that generation of K8ssandraCluster object never changes without user input.