Should image config customisations be handled atomically?

[Miles-Garnsey]

What happened?

A user asked a question on the discord server, where he'd put a custom image configuration in the spec and received an unexpected result.

https://discord.com/channels/836217371453685760/836217371453685763/1184189918457639035

spec:
  reaper:
    containerImage:
      registry: 'docker.mirrors.local'


Result:
  reaper:
    ServiceAccountName: default
    containerImage:
      registry: docker.mirrors.local
      tag: latest


expected:
  reaper:
    containerImage:
      name: cassandra-reaper
      registry: docker.mirrors.local
      repository: thelastpickle
      tag: 3.4.0

I think this is happening because any override of the image configuration overrides the entirety of the default image configuration, and latest is the default value for the image tag (so filled in by the API server) when left unspecified.

If this behaviour is unexpected (and I think it is) it might be advantageous to merge the user and default specs using goalesce so that OUR defaults are propagated instead of the k8s API server defaults.

┆Issue is synchronized with this Jira Story by Unito
┆Issue Number: K8OP-57