helm-generator git:20260303.39eba09B

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---
name: helm-generator
description: Comprehensive toolkit for generating best practice Helm charts and resources following current standards and conventions. Use this skill when creating new Helm charts, implementing Helm templates, scaffolding Chart.yaml and values.yaml, defining deployment templates, service definitions, ingress configurations, .tpl helpers, or building Helm projects from scratch. Trigger phrases include "create", "generate", "build", "scaffold" alongside terms like "kubernetes helm", "k8s charts", "helm package", "chart dependencies", "values.yaml", or "helm install".
---

# 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](https://helm.sh/docs/) | [Chart Best Practices](https://helm.sh/docs/chart_best_practices/) | [Template Functions](https://helm.sh/docs/chart_template_guide/function_list/) | [Sprig Functions](http://masterminds.github.io/sprig/)

## 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:

| Missing Information | Question to Ask |
|---------------------|-----------------|
| Image repository/tag | "What container image should be used? (e.g., nginx:1.25)" |
| Service port | "What port does the application listen on?" |
| Resource limits | "What CPU/memory limits should be set? (e.g., 500m CPU, 512Mi memory)" |
| Probe endpoints | "What health check endpoints does the app expose? (e.g., /health, /ready)" |
| Scaling requirements | "Should autoscaling be enabled? If yes, min/max replicas and target CPU%?" |
| Workload type | "What workload type: Deployment, StatefulSet, or DaemonSet?" |
| Storage requirements | "Does the application need persistent storage? Size and access mode?" |

**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
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
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):**
```yaml
# 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.

| Function | Purpose | Example |
|----------|---------|---------|
| `required` | Enforce required values | `{{ required "msg" .Values.x }}` |
| `default` | Fallback value | `{{ .Values.x \| default 1 }}` |
| `quote` | Quote strings | `{{ .Values.x \| quote }}` |
| `include` | Use helpers | `{{ include "name" . \| nindent 4 }}` |
| `toYaml` | Convert to YAML | `{{ toYaml .Values.x \| nindent 2 }}` |
| `tpl` | Render as template | `{{ tpl .Values.config . }}` |
| `nindent` | Newline + indent | `{{- include "x" . \| nindent 4 }}` |

## 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

| Issue | Solution |
|-------|----------|
| Template syntax errors | Check `{{-` / `-}}` matching, use `helm template --debug` |
| Undefined values | Use `default` or `required` functions |
| Indentation issues | Use `nindent` consistently |
| CRD validation fails | Verify apiVersion, check docs for required fields |

## Resources

### Scripts

| Script | Usage |
|--------|-------|
| `scripts/generate_chart_structure.sh` | `bash <script> <chart-name> <output-dir>` |
| `scripts/generate_standard_helpers.sh` | `bash <script> <chart-name> <chart-dir>` |

### References

| File | Content |
|------|---------|
| `references/helm_template_functions.md` | Complete template function guide |
| `references/resource_templates.md` | All K8s resource templates |
| `references/crd_patterns.md` | CRD patterns (cert-manager, Prometheus, Istio, ArgoCD) |

### Assets

| File | Purpose |
|------|---------|
| `assets/_helpers-template.tpl` | Standard helpers template |
| `assets/values-schema-template.json` | JSON Schema for values validation |

## Post-Generation Validation

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