helm: Stop helm chart from failing if zkHosts is not set

[jwitko]

Fixes #13745

Description

If a user deploying via the Apache Druid helm chart is while using druid-kubernetes-extensions then there is no need to set a zookeeper host however the helm chart will fail if the user does not.

This change will remove the requirement for setting a zookeeper host and adds a comment to the values file to help helm chart consumers understand.

Alternatives

An alternative design could have been to look for the druid config settings required in the documentation and base the conditional off of those but since they can be set at a per-process or global config level I thought it better to keep it simple.

Release note

Fixed: Helm chart no longer requires a ZooKeeper host be set for users using druid-kubernetes-extensions

This PR has:

• been self-reviewed.
• added documentation for new or modified features or behaviors.
• a release note entry in the PR description.
• added Javadocs for most classes and all non-trivial methods. Linked related entities via Javadoc links.
• added or updated version, license, or notice information in licenses.yaml
• added comments explaining the "why" and the intent of the code wherever would not be obvious for an unfamiliar reader.
• added unit tests or modified existing tests to cover new code paths, ensuring the threshold for code coverage is met.
• added integration tests.
• been tested in a test Druid cluster.

[dampcake]

Pretty sure this should be:

Suggested change

	{{- else .Values.zkHosts }}
	{{- else if .Values.zkHosts }}

[jwitko]

Ugh, yes I thought I had that. Thank you for catching. Will fix now.

[jwitko]

Fixed.

[a2l007]

LGTM, thank you for fixing this @jwitko!

[abhishekagarwal87]

@jwitko - can you pull the changes from the master branch? That might fix the build failures.

[jwitko]

@jwitko - can you pull the changes from the master branch? That might fix the build failures.
@abhishekagarwal87 I have rebased and should be up to date with the upstream master branch. Once this is merged I'll do the same to #13747

[a2l007]

@jwitko Thanks, Going forward please avoid rebasing and force pushing for commits after submitting the PR, since this makes it harder for the reviewers to see what has changed between commits.

[jwitko]

@jwitko Thanks, Going forward please avoid rebasing and force pushing for commits after submitting the PR, since this makes it harder for the reviewers to see what has changed between commits.

sure no problem. what is preferred? git merge upstream/master ?

[a2l007]

@jwitko Thanks, Going forward please avoid rebasing and force pushing for commits after submitting the PR, since this makes it harder for the reviewers to see what has changed between commits.

sure no problem. what is preferred? git merge upstream/master ?

Yes

[abhishekagarwal87]

Thank you @jwitko for your contribution.