Provide an upgrade path from helm2 to helm3 with Auto DevOps
Problem to solve
As a platform engineer, in order to support both legacy and new clusters, I need support for helm2 and helm3 based deployments within Auto DevOps.
Intended users
- Delaney (Development Team Lead)
- Sasha (Software Developer)
- Allison (Application Ops)
- Priyanka (Platform Engineer)
User experience goal
Be able to deploy to helm 2 or helm 3, and provide an upgrade path from helm 2 to 3.
Proposal
See #221187 (closed) for much details
We should leverage the on-going work in gitlab-org/charts/auto-deploy-app#70 (moved) to make a "safe" breaking change release, so that new feature only go to the Helm 3 variant going forward, but the Helm 2 variant receives bugfixes and security updates until %14.0.
- New users can get the Helm 3 version by default before %14.0,
- Existing users stay on the last stable Helm 2 release until they opt-in
- At %14.0, we do a one-time failing pipeline that informs the user that Helm 2 is fully unsupported (but they can still remain on that image)
If gitlab-org/charts/auto-deploy-app#70 (moved) does not allow the above setup, then consider an alternative