helmtest

A npm module which enables writing unit tests with nodejs / Jest.

Heavily inspired by Stono/helmtest.

Why not just use Stono/helmtest?

I originally wanted to update Stono/helmtest to fit my needs, but after attempting to customize it, I figured it's actually easier to rewrite one.

Differences with Stono/helmtest:

• Single js file for the core logic (lib/helmtest.js)
• Supports kubeconform instead of kubeval
• No Grunt and TypeScript
• Can be used as a npm library without assuming test framework and passing objects around global scope.
• Can also run independently as CLI. In this case jest is bundled instead of mocha/chai.

Getting Started

Running helmtest as npm module

Install helmtest:

npm install @rophy123/helmtest

To use helmtest in your code:

const helmtest = require('@rophy123/helmtest');

// Run `helm template` under working directory
helmtest.renderTemplate()
.then(results => {
  // results are JS objects converted from result YAML.
  // '[{"apiVesrion":"v1","kind":"ServiceAccount","metadata":...
  console.log(JSON.stringify(results));
});

The results object can be used to verify details. For example, in jest:

const helmtest = require('@rophy123/helmtest');

test('exmapleChart should render 4 resources', async () => {
  const result = await helmtest.renderTemplate();
  expect(result.length).toBe(4);
});

See API Spec for the options of helmtest.renderTemplate().

Running helmtest as CLI

Install jest along with helmtest globally:

npm install -g @rophy123/helmtest jest

...and then you can write unit tests under tests/ dir of your chart project without the need for package.json

A docker image is available which includes everything to run unit tests:

docker run -v $(pwd):/workspace ghcr.io/rophy/helmtest

See exampleChart/tests for example tests.

API Spec

helmtest currently only expose one method: helmtest.renderTemplate(options).

options is a object with option names, descriptions and defaults as below:

| Option | Description | Default | | -------------------- | ----------------------------------------------------------------------------------- | --------------------------------------------------- | | chartDir | Path to chart, the CHART arg in helm CLI: helm template [NAME] [CHART] [flags]. | '.' | | releaseName | Release name, the NAME arg in helm CLI: helm template [NAME] [CHART] [flags]. | 'release-name' | | values | Map of chart values to set. | {} | | valuesFiles | Paths to additional values.yaml. | [] | | templateFiles | Render only listed template files, e.g. ['templates/hpa.yaml'] | [] | | extraHelmArgs | Extra args to pass to helm CLI, e.g. --timeout=5s | [] | | helmBinary | Path to helm binary. | process.env.HELM_BINARY \|\| 'helm' | | loadYaml | if false, will return rendered template as raw string instead of js object. | true | | kubeconformEnabled | if true, will pass rendered template to kubeconform CLI to validate schema. | process.env.KUBECONFORM_ENABLED \|\| false | | kubeconformBinary | Path to kubeconform binary. | process.env.KUBECONFORM_BINARY \|\| 'kubeconform' | | kubeconformArgs | Args to pass to kubeconform CLI. Will append process.env.KUBECONFORM_EXTRA_ARGS. | ['-strict','-summary'] |