flux envsubst --strict ignores kustomize.toolkit.fluxcd.io/substitute: disabled label

[monotek]

Describe the bug

flux envsubst --strict ignores kustomize.toolkit.fluxcd.io/substitute: disabled label

Steps to reproduce

run "flux envsubst --strict" on a kustomization directory with a grafana dashboard which contains a "${Datasource}" var but also has the "kustomize.toolkit.fluxcd.io/substitute: disabled" label.

flux will complain:

✗ variable not set (strict mode): "Datasource"

Expected behavior

flux envsubst thros no error

Screenshots and recordings

No response

OS / Distro

github action

Flux version

2.4.0

Flux check

N/A

Git provider

No response

Container Registry provider

No response

Additional context

No response

Code of Conduct

• I agree to follow this project's Code of Conduct

[stefanprodan]

Currently the flux envsubst command behaves like the GNU envsubst with --strict being the only addition. The command is not aware of YAML nor Kubernetes types, it works by streaming the content of whatever is passed in stdin.
I don't think we should be changing the current behaviour, this would mean a major breaking change, for example I use this command in various scripts that have nothing to do with YAML content.

I'm for implementing the Kubernetes-aware envsubst under some opt-in flag.