Simple namespace blueprint by creating a helm chart from scratch

simple-helm-scratch

Create simplens-chart repo
git clone https://github.com/<user>/simplens-chart
cd simplens-chart
helm create scratch-chart
find scratch-chart -print
That assumed I wanted to run an application on Kubernetes. None of it is relevant.
mkdir simplens simplens/templates
rm -rf scratch-chart
Create the following files:
Chart.yaml:
apiVersion: v2
name: simplens
description: Simple Namespace blueprint
type: application
version: 0.1.0
appVersion: “1”
templates/namespaces.yaml:
{{- range .Values.namespaces }}
---
apiVersion: v1
kind: Namespace
metadata:
  name: {{ .name }}
  {{- if .labels }}
  labels:
    {{- range $key, $value := .labels }}
    {{ $key }}: {{ $value | quote }}
    {{- end }}
  {{- end }}
  {{- if .annotations }}
  annotations:
    {{- range $key, $value := .annotations }}
    {{ $key }}: {{ $value | quote }}
    {{- end }}
  {{- end }}
{{- end }}
templates/service-accounts.yaml:
{{- range .Values.namespaces }}
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: {{ $.Values.serviceAccountName }}
  namespace: {{ .name }}
{{- end }}
templates/role-bindings.yaml
{{- range .Values.namespaces }}
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  name: {{ $.Values.serviceAccountName }}-{{ $.Values.roleBindingRole }}
  namespace: {{ .name }}
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: {{ $.Values.roleBindingRole }}
subjects:
- kind: ServiceAccount
  name: {{ $.Values.serviceAccountName }}
  namespace: {{ .name }}
{{- end }}
values.yaml:
labels:
  istio-injection: enabled
annotations:
  network-type: mesh
serviceAccountName: app-admin
roleBindingRole: app-admin
namespaces:
  - name: backend1
  - name: backend2
  - name: backend3
helm template test simplens –output-dir test
Look at the output files
git add simplens
git commit
git push origin main
helm install mysetup simplens
helm uninstall mysetup