feat: adds DATAHUB_REVISION acyrl-datahub-actions deployment

[sgomezvillamor]

We are deploying action recipes in k8s configmaps which are mounted as k8s volumes in the acryl-datahub-actions deployment. However, updating the configmap also requires to manually rollup the pods in the k8s deployment so new recipes are picked up.

This is adding DATAHUB_REVISION from .Release.Revision as env var to force the redeploy of acryl-datahub-actions deployment with every new deployment.

This is following same strategy as GMS, and consumer jobs.

Checklist

• The PR conforms to DataHub's Contributing Guideline (particularly Commit Message Format)
• Links to related issues (if applicable)
• Tests for the changes have been added/updated (if applicable)
• Docs related to the changes have been added/updated (if applicable)

[darnaut]

Not sure why this needs to be an environment variable. Anyway, how to achieve the desired effect is documented at Automatically Roll Deployments.

[sgomezvillamor]

Not sure why this needs to be an environment variable. Anyway, how to achieve the desired effect is documented at Automatically Roll Deployments.

I didn't know about that helm feature or common practice. Definitely, it covers my use case: force the roll up of the pods. I understand DATAHUB_REVISION somehow follows the same approach: adding a difference in the k8s object so it forces the roll up. Whether difference is env var or annotation (checksum, random number, etc) is sort of implementation detail. Anyway, thanks for sharing @darnaut !

Specifically about the DATAHUB_REVISION environment var: I noted GMS or consumer jobs were rolled up in every deploy (even if no changes in the k8s objects) while acryl datahub actions didn't. I checked up differences and the only one I found was DATAHUB_REVISION. So I understood it was introduced to build such a behaviour.

I see the env var was mostly introduced here https://github.com/acryldata/datahub-helm/pull/254/files by @david-leifker . Maybe the author can clarify if the env var was introduced with such a purpose or it just became an additional side effect.

[darnaut]

DATAHUB_REVISION is an actual environment variable used by some DataHub components to build a version string.

[sgomezvillamor]

Following @darnaut suggestion, this PR is superseded by PR #487