Prometheus Set to Null Causes Helm Error

[kylegoch]

Welcome!

• Yes, I've searched similar issues on GitHub and didn't find any.
• Yes, I've searched similar issues on the Traefik community forum and didn't find any.

What version of the Traefik's Helm Chart are you using?

20.6.0

What version of Traefik are you using?

2.9.5

What did you do?

Already installed helm chart with some custom values and default values. Want to turn off prometheus monitoring since it was defaulted to on.

I set metrics.prometheus: null as outlined in the values.yaml :
https://github.com/traefik/traefik-helm-chart/blob/master/traefik/values.yaml#L263

What did you see instead?

I receive this error when doing a helm apply

STDERR:
  Error: Failed to render chart: exit status 1: Error: template: traefik/templates/service-metrics.yaml:6:20: executing "traefik/templates/service-metrics.yaml" at <.Values.metrics.prometheus.service>: nil pointer evaluating interface {}.service
  Use --debug flag to render out invalid YAML
  Error: plugin "diff" exited with error

COMBINED OUTPUT:
  Error: Failed to render chart: exit status 1: Error: template: traefik/templates/service-metrics.yaml:6:20: executing "traefik/templates/service-metrics.yaml" at <.Values.metrics.prometheus.service>: nil pointer evaluating interface {}.

This same error message is mentioned in #741 however the main issue from that issue was resolved updating Helm.

What is your environment & configuration?

Installed using helmfile which is a plugin for helm. Helmfile currently works and updates chart as expected as long as metrics.prometheus: null is not set.

Helm v3.10.1
EKS v1.22.15

Additional Information

No response

[mloiseleur]

Thanks for your report @kylegoch
The PR #756 should fix your issue. This PR includes more tests on this use case.