rabbitmq upgrade (breaking change for rabbitmq users)

[Jancis]

RabbitMQ subchart upgrade to latest available, contains breaking change.

1. Configuration change - authentication section is moved from rabbitmq to auth. If you have defined credentials like this:

rabbitmq:
  enabled: true
  rabbitmq:
    username: "foo"
    password: "bar"

Then it becomes this:

rabbitmq:
  enabled: true
  auth:
    username: "foo"
    password: "bar"
    erlangCookie: "baz"

If you have not defined credentials, you can get username, password and erlang cookie from secret (<release-name>-rabbitmq).

rabbitmq:
  enabled: true
  auth:
    username: "foo"
    password: "bar"
    erlangCookie: "baz"

2. You have to delete rabbitmq statefulset before deployment because stateful fields in statefulset have been changed or it will fail the deployment. You can delete with --cascade=orphan flag to keep rabbitmq pod running during deployment, but you'll need to do statefulset rollout manually.

If you do not delete statefulset, deployment will fail with following error:

Error: UPGRADE FAILED: cannot patch "-rabbitmq" with kind StatefulSet: StatefulSet.apps "-rabbitmq" is invalid: spec: Forbidden: updates to statefulset spec for fields other than 'replicas', 'ordinals', 'template', 'updateStrategy', 'persistentVolumeClaimRetentionPolicy' and 'minReadySeconds' are forbidden

3. You have to update rabbitmq credentials by:

3.a either executing into running container after deployment and changing password (while it's still in non-ready state due to failing probes)

rabbitmqctl change_password "$RABBITMQ_USERNAME" "$(cat /opt/bitnami/rabbitmq/secrets/rabbitmq-password)"

3.b or adding updatePassword: true to configuration:

rabbitmq:
  enabled: true
  auth:
    username: "foo"
    password: "bar"
    erlangCookie: "baz"
    updatePassword: true