helmify

README

Helmify

Helmify reads kubernetes resources from std.in and produces a Helm chart.

Main use-case is to create Helm charts for kubernetes operators build with Operator-SDK or Kubebuilder.

Run

Clone repo and execute command:

cat test_data/kustomize.output | go run cmd/helmify/main.go mychart

Will generate mychart Helm chart form file test_data/kustomize.output representing typical operator kustomize output.

Integrate to your Operator-SDK/Kubebuilder project

Tested with operator-sdk version: "v1.8.0".

1. Open Makefile in your operator project generated by Operator-SDK or Kubebuilder.
2. Add these lines to Makefile:

HELMIFY = $(shell pwd)/bin/helmify
helmify:
	$(call go-get-tool,$(HELMIFY),github.com/arttor/helmify/cmd/helmify@v0.2.2)

helm: manifests kustomize helmify
	$(KUSTOMIZE) build config/default | $(HELMIFY)

1. Run make helm in project root. It will generate helm chart with name 'chart' in 'chart' directory.

Available options

Helmify takes a chart name for an argument. Usage:

helmify [flags] CHART_NAME - CHART_NAME is optional. Default is 'chart'.

flag	description	sample
-h -help	Prints help	helmify -h
-v	Enable verbose output. Prints WARN and INFO.	helmify -v
-vv	Enable very verbose output. Also prints DEBUG.	helmify -vv

Status

Supported default operator resources:

• deployment
• service
• RBAC (serviceaccount, (cluster-)role, (cluster-)rolebinding)
• configs (configmap, secret)
• webhooks (cert, issuer, ValidatingWebhookConfiguration)

Known issues

• Helmify defines application (operator) name as the shortest common prefix of k8s objects names. It is possible because operator-sdk using operator name as prefix by default.
• Helmify will not overwrite Chart.yaml file if presented. Done on purpose.
• Helmify will not delete existing template file, only overwrite. So, if you delete CRD, re-run kustomize | helmify crd file will still be in templates directory. (todo: add option for this)
• Helmify overwrites templates and values files on every run. This meas that all your manual changes in helm template files will be lost on the next run. Use kustomize /config folder as a single source of true and make changes there.

Develop

To support a new type of k8s object template:

1. Implement helmify.Processor interface. Place implementation in pkg/processor. The package contains examples for most k8s objects.
2. Register your processor in the pkg/app/app.go
3. Add relevant input sample to test_data/kustomize.output.

Test

For manual testing, run program with debug output:

cat test_data/kustomize.output | go run cmd/helmify/main.go -vv mychart

Then inspect logs and generated chart in ./mychart directory.

To execute tests, run:

go test ./...

Beside unit-tests, project contains e2e test pkg/app/app_e2e_test.go. It's a go test, which uses test_data/kustomize.output to generate a chart in temporary directory. Then runs helm lint --strict to check if generated chart is valid.