Using include inside range in Go templates (helm)

Question

I have a template that get rendered several times with a range iteration and I can access variables external variables such as $.Release.Name without a problem. However, when I include templates I can't get it to work:

{{ range $key, $val := $.Values.resources }}
      ...
      annotations:
        checksum/config: {{ include (print $.Template.BasePath "/secrets.yaml") . | sha256sum }}
{{ end }}

And in secrets.yaml:

apiVersion: "v1"
kind: "Secret"
metadata:
  name: {{ $.Release.Name }}-secrets

I got this error:

Error: render error in "botfront-project/templates/deployment.yaml": template: [filename] :19:28: executing [filename] at <include (print $.Template.BasePath "/secrets.yaml") .>: error calling include: template: .../secrets.yaml:4:19: executing ".../secrets.yaml" at <$.Release.Name>: nil pointer evaluating interface {}.Name

How do I access variables inside an included template?

Answer 1

TL;DR;

just replace . with $ to use the global scope instead of the local one you created .

Example:

{{- include "my-chart.labels" $ | nindent 4 }}

Explanations

According to the docs, https://helm.sh/docs/chart_template_guide/control_structures/#modifying-scope-using-with:

we can use $ for accessing the object Release.Name from the parent scope. $ is mapped to the root scope when template execution begins and it does not change during template execution

With range we change the scope inside the loop. Indeed, {{- include "my-chart.labels" . | nindent 4 }} would invoke the current scope ..

So if you dig into this "scope" thing in helm doc, you eventually find this part: https://helm.sh/docs/chart_template_guide/variables/

With this example:

{{- range .Values.tlsSecrets }}
apiVersion: v1
kind: Secret
metadata:
  name: {{ .name }}
  labels:
    # Many helm templates would use `.` below, but that will not work,
    # however `$` will work here
    app.kubernetes.io/name: {{ template "fullname" $ }}
    # I cannot reference .Chart.Name, but I can do $.Chart.Name
    helm.sh/chart: "{{ $.Chart.Name }}-{{ $.Chart.Version }}"
    app.kubernetes.io/instance: "{{ $.Release.Name }}"
    # Value from appVersion in Chart.yaml
    app.kubernetes.io/version: "{{ $.Chart.AppVersion }}"
    app.kubernetes.io/managed-by: "{{ $.Release.Service }}"
type: kubernetes.io/tls
data:
  tls.crt: {{ .certificate }}
  tls.key: {{ .key }}
---
{{- end }}