Helmfile: Variables in kustomization.yaml

[olfway]

Is it possible to use go template variables in kustomization.yaml file?

For example I want to have something like this:

$ cat kustomization.yaml
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization

resources:
- https://github.com/kubernetes-sigs/metrics-server/releases/download/{{ .Values.appVersion }}/components.yaml

patches:
- target:
    group: apps
    version: v1
    kind: Deployment
    name: metrics-server
  path: patches/deployment.yaml

[mumoshu]

@olfway Hey! Interesting idea. It's impossible today, but worth investigating.

What .Values.appVersion should refer to, btw? The values of the release, or helmfile state(environment) values?

[mumoshu]

I.e. what if helmfile allowed this?

releases:
- name: yourapp
  kustomization: some/dir/kustomization.yaml.gotmpl
  values:
  - appVersion: ver

[olfway]

I thought .Values. should refer to the values of the release, like in your example

[darkn3rd]

I absolutely need this feature. My use case is this use a namespace for the installation but also set the subjects[0].namespace in ClusterRoleBinding.rbac.authorization.k8s.io. So the question is, how do I inject env var of ROOK_NFS_OPERATOR_NAMESPACE into the kustomize with helmfile?

releases:
  {{- if eq (env "NFS_STRATEGY") "rook" }}
  - name: rook-nfs-operator
    namespace: {{ env "ROOK_NFS_OPERATOR_NAMESPACE" | default "rook-nfs-system" }}
    chart: ./rook-nfs-operator
    hooks:
      - events:
          - prepare
          - cleanup
        command: ./helmify.sh
        args:
          - "{{`{{if eq .Event.Name \"prepare\"}}build{{else}}clean{{end}}`}}"
          - "{{`{{.Release.Chart}}`}}"
          - default
  {{- end }}

In my rook-nfs-operator-kustomize/base/operator.yaml, I will have this:

kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
  name: rook-nfs-operator
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: rook-nfs-operator
subjects:
- kind: ServiceAccount
  name: rook-nfs-operator
  namespace: $(ROOK_NFS_OPERATOR_NAMESPACE)

[mumoshu]

@darkn3rd Hey! How do you define ROOK_NFS_OPERATOR_NAMESPACE in your kustomization? Is it just an entry under kustomize vars?

AFAIK, it's kustomize's own restriction that you can't inject arbitrary built-time args. I'm not sure how we workaround that.