[Question] Helm upgrade option for Atomic

[jpae]

Looking at helm-operator there was a possible Atomic option. Is the Atomic option configurable in helm-controller?

[kingdonb]

Helm Operator has the atomic option, which is not quite related to the roadmap entry for Helm Controller:

• https://fluxcd.io/roadmap/#flux-helm-ga-q2-2023 ("Atomic Reconciliation of Helmreleases")

There are a few different things that people mean when they say atomic, with respect to Helm. That flag from Helm Operator atomic was replaced in Flux v2, with a more broadly scoped configuration:

https://fluxcd.io/flux/components/helm/helmreleases/#configuring-failure-remediation

Can you say a bit more about what you were hoping to get from the Atomic option? Is it just a drop-in replacement for the old behavior that you're looking for?

remediateLastFailure: false - will leave the failed resources in place (so you can debug what went wrong, this is the default behavior, it shouldn't generally result in downtime because Helm uses the rolling deployment but that depends on what you deployed, and sure it might be messy to leave things in a failed state like this if you don't have someone on call to handle it right away) whereas...

remediateLastFailure: true - will actually roll back the failure when the number of retries you have configured is exhausted. That's similar to atomic from HelmRelease in Helm Operator. When the release is failed, the changes get "undo" and the rollout is fully reverted. So, in brief, "atomic" mode has been replaced by "failure remediation" settings in Helm Controller.

Hope that is what you were looking for!

The "atomic" stuff that's discussed in the roadmap is all about whether or not Helm Controller can perform drift detection and reliably revert changes to your Helm release's manifests (output) when someone makes a change inside the cluster. That's a different thing, was never supported in Helm Operator before, but if that's what you are looking for, I hear it might be landing soon (at least in an experimental form!)

• Experimental support of drift detection #617

[hiddeco]

Closing this, as I think @kingdonb has answered your question accordingly. The changes Kingdon is further talking about have landed in the v0.37.0 release of the helm-controller, and you can read more about it in this blog post.