What The Helm?

Dear Friend,

In the Kubernetes world, there's no shortage of buzzwords. One among them is Helm.

And Helm goes a step ahead. At first glance, it would seem to overlap with Kubernetes itself!

But what a Helm is a package manager in the Kubernetes world, just like a homebrew, chocolatey, and npm.

Helm is the best way to find, share, and use software built for?Kubernetes - Helm.sh

Why Helm?

With helm, a bunch of related YAML files can be grouped into a single chart, and they can all be deployed with a single command.

In addition, you can version control, rollback, and uninstall as required.

As you can see, Helm acts as a higher-level abstraction layer and removes the complexity of individual YAML file deployments.

For example, could you imagine deploying these YAML files individually?

Multiply the effort by the number of environments, such as dev, staging, and production.

However, the above complex installation can be done in a single line with Helm.

Like here,

helm install my-release oci://registry-1.docker.io/bitnamicharts/nginx        

Simply, it eases an infra-engineer deployment work.

A pasta pack from store is quicker than making them ourself with wheat, water and eggs.

How does Helm work?

Helm charts have a directory structure like the one here.

mychart/        --> chart name
  Chart.yaml    --> contains a description of the chart.
  values.yaml   --> contains the default values for a chart.
  charts/       --> contain other dependant charts 
  templates/    --> directory is for template files
  ...        

When an engineer tries to install a chart like this,

1. The helm scans and sends the files inside the templates folder to a template rendering engine.
2. The template rendering engine then sends the result to the helm.
3. The resulting file would be sent to Kubernetes for deployment.

The templating here can be deemed similar to resume templates we use for job searches.

Helm gives the flexibility to create templates with placeholders, later these placeholders would be populated with values from file values.yaml, helpers.tpl etc.,

I hope you enjoyed the article. Happy helming.

What's Next?

• Create a basic helm chart yourself. Check the official helm site
• You can complete this in 5 - 10 minutes, given that you have docker desktop installed and minikube started. Take advantage of this step.
• Subscribe to DevOps Stories and join 20,000+ Engineers.