Helm Chart Best Practices

1. Chart Structure

Maintain a consistent chart structure:

helm create my-chart

• Chart.yaml - Contains metadata about the chart.
• values.yaml - Default configuration values for the chart.
• templates/ - Directory for Kubernetes YAML templates.
• charts/ - Directory for chart dependencies.
• README.md - Documentation for the chart.

2. Use Values Files

Utilize values.yaml to define default configuration. This allows users to override values without modifying the template files.

apiVersion: v1
kind: ConfigMap
metadata:
  name: {{ .Release.Name }}-config
data:
  key: {{ .Values.key }}

3. Templates Best Practices

Keep your templates DRY (Don't Repeat Yourself) by using helper templates:

{{/* Define a helper template */}}
{{- define "mychart.fullname" -}}
{{- .Release.Name }}-{{ .Chart.Name }}
{{- end -}}

{{/* Use the helper template in your resources */}}
apiVersion: v1
kind: Service
metadata:
  name: {{ template "mychart.fullname" . }}

4. Versioning

Follow semantic versioning for your charts:

• Major version changes for incompatible API changes.
• Minor version changes for adding functionality in a backwards-compatible manner.
• Patch version changes for backwards-compatible bug fixes.

5. Documentation

Provide clear and comprehensive documentation in your README.md file:

• How to install the chart.
• Configuration options available in values.yaml.
• Usage examples with explanations.