[occm] The nodeSelector key is not empty in the helm chart in release v1.29.0

[babykart]

**This is a BUG REPORT **:

/kind bug

What happened:
Since the release v1.29.0, the nodeSelector key in the file values.yaml of the helm chart is no longer empty and therefore requires positioning the following label node-role.kubernetes.io/controlplane: "" on the workers where the daemonSet must be deployed.

What you expected to happen:
The nodeSelector key in the file values.yaml of the helm chart should be empty.

nodeSelector: {}

How to reproduce it:
Install occm v1.29.0 with the helm chart.

Environment:

• openstack-cloud-controller-manager(or other related binary) version: v1.29.0

Let me know if you need a PR.
Regards.

[Michal Dulko]

This got introduced in #2346. @wwentland, would you care to comment here?

As a workaround, would just setting nodeSelector: {} in your values.yaml help here? Why would you think that no nodeSelector is a preference?

[babykart]

@dulek The workaround doesn't help if I need to add my own nodeSelector.
The fact that there is already a default value, helm will 'add' the two values and therefore in this case I will be forced to set the default value to the nodes as well besides mine.

For example, I want to use my.corp.selector/front: "true", the nodeSelector generated by helm would be:

<...>
    spec:
      nodeSelector:
        my.corp.selector/front: "true"
        node-role.kubernetes.io/control-plane: ""
<...>

[Michal Dulko]

@babykart:

I was able to do what you need with this values.yaml:

nodeSelector:
  node-role.kubernetes.io/control-plane: null
  my.corp.selector/front: "true"

This gets my helm install --dry-run to render this:

    spec:
      nodeSelector:
        my.corp.selector/front: "true"

Based on Helm Docs.

Can I close this issue now?

[babykart]

@dulek thx. I didn't know about this feature of helm.
But should we therefore consider that this is the new behavior from version 1.29?

[Michal Dulko]

I think so. I believe @wwentland motivation to change this was to follow what AWS provider does and it makes sense to me: https://github.com/kubernetes/cloud-provider-aws/blob/master/charts/aws-cloud-controller-manager/values.yaml#L14-L16. Your use case is still valid, but since we've figured out how to override the default, I think we should keep the current 1.29 behavior.

[babykart]

I admit I don't fully understand what the specific AWS implementation has to do with it.
I only deploy Kubernetes clusters in on-premise environments.
If it comes to dealing with this specific implementation in the helm chart, wouldn't it make more sense to add a specific block of documentation in the README.md?

[Michal Dulko]

I admit I don't fully understand what the specific AWS implementation has to do with it. I only deploy Kubernetes clusters in on-premise environments.

But in the end AWS and OpenStack K8s clusters shouldn't be too different. The idea is that cloud-provider-openstack being part of the control plane, lands on the control plane nodes. This should basically be true for any platform and any cloud-provider.

If it comes to dealing with this specific implementation in the helm chart, wouldn't it make more sense to add a specific block of documentation in the README.md?

Sure thing, docs are always welcome! Can you prepare the PR? I'll be happy to review and approve it.