pulsar-manager adding support for existing secret

[doug-ba]

Fixes #477

Motivation

The existing solution to automatically generate credentials doesn't work in argocd, it detects a constant difference and changes the credentials repeatedly. The alternative of specifying credentials in values files committed to source control is not good practice.
Allowing users to use an existing secret provisioned by the secrets management solution of their choice solves this problem.

Modifications

Makes the pulsar-manager secret generated by the chart not be created if the value pulsar_manager.admin.existingSecret is specified.
Makes the pulsar-manager initialize job and statefulset utilize an existing secret if it's specified.

Verifying this change

• Make sure that the change passes the CI checks.

[lhotari]

LGTM. Thanks for the contribution!

[robertdumitrescu]

This does not work. I just tried to specify a secret with the correct keys and is still created its own secret.

pulsar_manager:
  admin:
    existingSecret: local-dev-pulsar-secret-from-es

[doug-ba]

There isn’t a release that contains this change yet.

[robertdumitrescu]

When will this be released then? Any timeline?

[lhotari]

When will this be released then? Any timeline?

@robertdumitrescu next release in 1-2 weeks

[lhotari]

@robertdumitrescu The next release is in voting stage. Please help validate the release: https://lists.apache.org/thread/t4vlvk0nwd3gzo50t466cqy5h95l81gb . The release voting email shows how you can use the release candidate version. Would you be able to test that existing secret works as expected?

[robertdumitrescu]

Unfortunately, I won't be able to explore this due to other commitments.