Helm Chart Generator

Overview

Generate production-ready Helm charts with best practices built-in. Create complete charts or individual resources with standard helpers, proper templating, and automatic validation.

Official Documentation:

• Helm Docs | Chart Best Practices | Template Functions | Sprig Functions

When to Use This Skill

Use for creating/generating Helm charts and templates. For validation/linting of existing charts use devops-skills:helm-validator; for raw K8s YAML (no Helm) use k8s-generator.

Chart Generation Workflow

Stage 1: Understand Requirements

REQUIRED: Use AskUserQuestion if any of these are missing or ambiguous:

Do NOT assume values for critical settings. Ask first, then proceed.

Stage 2: CRD Documentation Lookup

If custom resources are needed:

1. Try context7 MCP first:

   mcp__context7__resolve-library-id with operator name
   mcp__context7__get-library-docs with topic for CRD kind

2. Fallback to WebSearch:

   "<operator>" "<CRD-kind>" "<version>" kubernetes documentation spec

See references/crd_patterns.md for common CRD examples.

Stage 3: Create Chart Structure

Use the scaffolding script:

bash scripts/generate_chart_structure.sh <chart-name> <output-directory> [options]

Script options:

• --image <repo> - Image repository (default: nginx). Note: Pass only the repository name without tag (e.g., redis not redis:7-alpine)
• --port <number> - Service port (default: 80)
• --type <type> - Workload type: deployment, statefulset, daemonset (default: deployment)
• --with-templates - Generate resource templates (deployment.yaml, service.yaml, etc.)
• --with-ingress - Include ingress template
• --with-hpa - Include HPA template
• --force - Overwrite existing chart without prompting

Important customization notes:

• The script uses http as the default port name in templates. Customize port names for non-HTTP services (e.g., redis, mysql, grpc)
• Templates include checksum annotations for ConfigMap/Secret changes (conditionally enabled via .Values.configMap.enabled and .Values.secret.enabled)

Stage 4: Generate Standard Helpers

Use the helpers script or assets/_helpers-template.tpl:

bash scripts/generate_standard_helpers.sh <chart-name> <chart-directory>

Stage 5: Generate Templates

⚠️ CRITICAL REQUIREMENT: Read Reference Files NOW

You MUST use the Read tool to load these reference files at this stage, even if you read them earlier in the conversation:

1. Read references/resource_templates.md - for the specific resource type patterns
2. Read references/helm_template_functions.md - for template function usage
3. Read references/crd_patterns.md - if generating CRD resources (ServiceMonitor, Certificate, etc.)

Why: Prior context may be incomplete or summarized. Reading reference files at generation time guarantees all patterns, functions, and examples are available for accurate template creation.

Do NOT skip this step. Template quality depends on having current reference patterns loaded.

Reference templates for all resource types in references/resource_templates.md:

• Workloads: Deployment, StatefulSet, DaemonSet, Job, CronJob
• Services: Service, Ingress
• Config: ConfigMap, Secret
• RBAC: ServiceAccount, Role, RoleBinding, ClusterRole, ClusterRoleBinding
• Network: NetworkPolicy
• Autoscaling: HPA, PodDisruptionBudget

Key patterns (MUST include in all templates):

# Use helpers for names and labels
metadata:
  name: {{ include "mychart.fullname" . }}
  labels: {{- include "mychart.labels" . | nindent 4 }}

# Conditional sections with 'with'
{{- with .Values.nodeSelector }}
nodeSelector: {{- toYaml . | nindent 2 }}
{{- end }}

# Checksum annotation (REQUIRED for Deployments/StatefulSets/DaemonSets to trigger restarts on config changes)
annotations:
  checksum/config: {{ include (print $.Template.BasePath "/configmap.yaml") . | sha256sum }}

Stage 6: Create values.yaml

Structure guidelines:

• Group related settings logically
• Document every value with # -- comments
• Provide sensible defaults
• Include security contexts, resource limits, probes

See assets/values-schema-template.json for JSON Schema validation.

Stage 7: Validate

Run validation using devops-skills:helm-validator skill (helm lint, template render, schema checks, dry-run).

Template Functions Quick Reference

See references/helm_template_functions.md for complete guide.

Working with CRDs

See references/crd_patterns.md for complete examples. Ship CRDs in crds/ directory (not templated); template CR instances in templates/.

Converting Manifests to Helm

1. Parameterize names (use helpers) and extract values
2. Apply label/conditional patterns, use toYaml for complex objects
3. Create _helpers.tpl with standard helpers
4. Validate with devops-skills:helm-validator

Error Handling

Resources

Scripts

References

Assets

Post-Generation Validation

After generating charts, invoke devops-skills:helm-validator to ensure quality.