yaml2helm

Convert Kubernetes YAML manifests into Helm charts automatically.

Features

• Multiple input formats: File, directory, stdin, or Kustomize with multi-document YAML support
• Smart value extraction: Automatically extracts common fields (image, replicas, resources, etc.)
• Resource-scoped values: Zero conflicts by organizing values per resource
• CRD support: Separate CRDs into crds/ directory per Helm best practices
• Namespace handling: Template namespaces or preserve originals
• Name templating: Preserve original names or add release name prefix
• Deterministic output: Stable ordering and idempotent reruns
• JSON Schema generation: Optional values.schema.json for validation
• Helm integration: Built-in helm lint and helm template validation
• Kustomize support: Direct integration with kustomize build
• Makefile generation: Optional Makefile with helm workflow targets
• Enhanced helpers: Comprehensive _helpers.tpl with apiVersion helpers
• Comprehensive reporting: Track conversions with detailed statistics

Installation

pip install -e .

For development:

pip install -e ".[dev]"

Usage

Basic conversion

yaml2helm --name myapp --in ./manifests --out ./charts

From stdin

kubectl get deployment nginx -o yaml | yaml2helm --name nginx --out ./charts

From Kustomize

yaml2helm --name myapp --kustomize ./overlays/production --out ./charts

With Makefile generation

yaml2helm --name myapp --in ./manifests --out ./charts --makefile

This creates a Makefile.helm with targets for building and managing your Helm chart:

make -f Makefile.helm help      # Show available targets
make -f Makefile.helm helm      # Generate chart
make -f Makefile.helm helm-lint # Lint the chart

With CRD separation

yaml2helm --name myapp --in ./manifests --out ./charts --crd-dir

This places CustomResourceDefinitions in crds/ directory per Helm best practices.

Preserve original namespaces

yaml2helm --name myapp --in ./manifests --out ./charts --preserve-ns

Keeps original namespaces instead of templating to {{ .Release.Namespace }}.

Add release name prefix

yaml2helm --name myapp --in ./manifests --out ./charts --prefix-release-name

Prefixes resource names with {{ include "myapp.fullname" . }}.

Advanced options

yaml2helm \
  --name myapp \
  --in ./manifests \
  --out ./charts \
  --resource-scoped \
  --crd-dir \
  --preserve-ns \
  --schema \
  --strict \
  --makefile

CLI Options

Option	Description	Default
--name, -n	Chart name (required)	-
--in, -i	Input file/directory (stdin if omitted)	stdin
--kustomize, -k	Run kustomize build on directory	-
--out, -o	Output directory	./charts
--resource-scoped/--field-scoped	Scope values to resources (recommended)	true
--crd-dir	Place CRDs in separate crds/ directory	false
--preserve-ns	Preserve original namespaces (don't template)	false
--original-name/--prefix-release-name	Preserve names or add release prefix	true
--include-cluster	Include cluster-specific fields	false
--schema/--no-schema	Generate values.schema.json	true
--lint/--no-lint	Run helm lint	true
--template/--no-template	Run helm template	true
--strict	Fail on helm errors	false
--makefile	Generate Makefile.helm	false

Output Structure

charts/
└── myapp/
    ├── Chart.yaml
    ├── values.yaml
    ├── values.schema.json
    ├── README.md
    ├── .helmignore
    └── templates/
        ├── _helpers.tpl
        ├── NOTES.txt
        ├── 01-deployment-nginx.yaml
        └── 02-service-nginx.yaml

Extracted Values

yaml2helm automatically extracts and templates:

• Image: repository and tag
• Replicas: for Deployments, StatefulSets
• Resources: CPU/memory limits and requests
• Service: type and ports
• Ingress: rules and TLS
• Environment variables: from containers
• Node affinity: nodeSelector, tolerations, affinity
• HPA: min/max replicas and target CPU

Examples

Convert a deployment

# Input: deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx
spec:
  replicas: 3
  template:
    spec:
      containers:
      - name: nginx
        image: nginx:1.19

# Run conversion
yaml2helm --name nginx --in deployment.yaml --out ./charts

# Output: charts/nginx/values.yaml
image:
  repository: nginx
  tag: "1.19"
replicas: 3

# Output: charts/nginx/templates/01-deployment-nginx.yaml (templated)
spec:
  replicas: {{ .Values.replicas }}
  template:
    spec:
      containers:
      - image: {{ .Values.image.repository }}:{{ .Values.image.tag }}

Multi-document YAML

# Input file with multiple resources separated by ---
yaml2helm --name myapp --in multi.yaml --out ./charts

Directory of manifests

# Convert all YAML files in a directory
yaml2helm --name myapp --in ./k8s-manifests --out ./charts

Testing

Run tests:

pytest tests/ -v

With coverage:

pytest tests/ --cov=yaml2helm --cov-report=term-missing

Algorithm

1. Discovery: Find YAML files, split multi-docs, parse with ruamel.yaml
2. Validation: Check for apiVersion, kind, metadata.name
3. Normalization: Sort maps and lists for deterministic output
4. Extraction: Extract values per heuristics, replace with Helm templates
5. Writing: Generate template files as NN-<kind>-<name>.yaml
6. Schema: Create values.schema.json from extracted values
7. Validation: Run helm lint and helm template if available

Requirements

• Python 3.11+
• Optional: helm CLI for validation

Dependencies

• typer: CLI framework
• ruamel.yaml: YAML parsing with comments preservation
• jinja2: Template rendering
• jsonschema: Schema validation
• rich: Terminal formatting

Development

# Install dev dependencies
pip install -e ".[dev]"

# Run tests
pytest

# Run with coverage
pytest --cov=yaml2helm

# Test with helm integration
yaml2helm --name demo --in tests/data/input --out /tmp/charts
helm lint /tmp/charts/demo
helm template test /tmp/charts/demo

License

MIT