Standard Pod Labels Convention

This rule applies to files matching the patterns above.

# Standard Pod Labels Convention

## Rule
All Kubernetes resources MUST include the standard `app.kubernetes.io` label set for consistent identification, selection, and tooling integration.

## Required Labels
```yaml
metadata:
  labels:
    app.kubernetes.io/name: myapp          # Application name
    app.kubernetes.io/instance: myapp-prod # Unique instance identifier
    app.kubernetes.io/version: "2.1.0"     # Application version
    app.kubernetes.io/component: api       # Component within architecture
    app.kubernetes.io/part-of: platform    # Higher-level application
    app.kubernetes.io/managed-by: helm     # Tool managing this resource
```

## Good Examples
```yaml
# API Deployment
metadata:
  name: payment-api
  labels:
    app.kubernetes.io/name: payment-api
    app.kubernetes.io/instance: payment-api-prod
    app.kubernetes.io/version: "3.2.1"
    app.kubernetes.io/component: api
    app.kubernetes.io/part-of: payment-platform
    app.kubernetes.io/managed-by: argocd
    team: payments
    environment: production

# Database StatefulSet
metadata:
  name: payment-db
  labels:
    app.kubernetes.io/name: payment-db
    app.kubernetes.io/instance: payment-db-prod
    app.kubernetes.io/version: "16.2"
    app.kubernetes.io/component: database
    app.kubernetes.io/part-of: payment-platform
    app.kubernetes.io/managed-by: helm
```

## Bad Examples
```yaml
# BAD: No labels
metadata:
  name: my-deployment

# BAD: Non-standard labels only
metadata:
  labels:
    app: myapp
    role: backend

# BAD: Missing version and component
metadata:
  labels:
    app.kubernetes.io/name: myapp
```

## Why Labels Matter
- **Service selection**: Services use label selectors to route traffic
- **Monitoring**: Prometheus discovers targets via labels
- **Cost allocation**: Labels enable per-team/per-app cost tracking
- **GitOps**: ArgoCD and Flux use labels for resource management

## Enforcement
- Use OPA Gatekeeper or Kyverno to require minimum label set
- Helm chart templates should include labels by default
- CI validation to reject manifests without required labels