Helm Chart Structure Standards

This rule applies to files matching the patterns above.

# Helm Chart Structure Standards

## Rule
Every Helm chart MUST include Chart.yaml, values.yaml, templates/_helpers.tpl, templates/NOTES.txt, and README.md. All resources MUST use template helpers for names and labels.

## Required File Structure
```
mychart/
├── Chart.yaml            # REQUIRED: Chart metadata
├── values.yaml           # REQUIRED: Default values
├── values.schema.json    # RECOMMENDED: JSON schema
├── README.md             # REQUIRED: Documentation
├── templates/
│   ├── _helpers.tpl      # REQUIRED: Template helpers
│   ├── NOTES.txt         # REQUIRED: Post-install notes
│   ├── deployment.yaml   # Application resources
│   ├── service.yaml
│   ├── ingress.yaml
│   └── tests/
│       └── test-connection.yaml
└── charts/               # Dependencies (if any)
```

## Chart.yaml Requirements
```yaml
apiVersion: v2
name: myapp
description: A Helm chart for MyApp
type: application
version: 1.0.0        # Chart version (semver)
appVersion: "2.1.0"   # Application version
maintainers:
  - name: platform-team
    email: platform@mycompany.com
```

## Good Examples
```yaml
# All resources use helpers
metadata:
  name: {{ include "myapp.fullname" . }}
  labels:
    {{- include "myapp.labels" . | nindent 4 }}
```

## Bad Examples
```yaml
# BAD: Hardcoded names and labels
metadata:
  name: myapp-deployment
  labels:
    app: myapp
    version: "1.0"

# BAD: Missing NOTES.txt, _helpers.tpl, or README
```

## Enforcement
- helm lint (validates chart structure)
- ct (chart-testing) in CI pipeline
- kubeconform for rendered manifest validation
- Code review checklist for chart structure compliance