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Helm is a package manager for Kubernetes that allows developers and operators to more easily package, configure, and deploy applications and services onto Kubernetes clusters in the form of helm chart. What is a helm chart? It is basically a set of templates and a file containing variables used to fill these templates based on the custom values and configurations.

Helm is an official Kubernetes project and is part of the Cloud Native Computing Foundation, a non-profit that supports open source projects in and around the Kubernetes ecosystem.

What Helm can do:

  • Install software.

  • Automatically install software dependencies.

  • Upgrade software.

  • Configure software deployments.

  • Fetch software packages from repositories.

Helm provides this functionality through the following components:

  • A command line tool, helm, which provides the user interface to all Helm functionality.

  • Helm permissions are now simply evaluated using kubeconfig file. Cluster administrators can, therefore, restrict user permissions at whatever level they want while releases are still recorded in-cluster, and the rest of Helm functionality remains the same.

  • The Helm packaging format, called charts.

  • An official curated charts repository with prepackaged charts for popular open-source software projects.

Let’s look at DIGIT Sample app deployment using Helm

Pre-Requisites: Helm3 Installation

Let’s have a look at an eGov app example. (Assuming that already have Helm installed and configured at this point).


To start working on a chart, Helm uses a simple command create:

$ helm create my-app

After that Helm creates a directory with the following layout:

my-app/
├── charts
├── Chart.yaml
├── templates
│   ├── deployment.yaml
│   ├── _helpers.tpl
│   ├── ingress.yaml
│   ├── NOTES.txt
│   └── service.yaml
└── values.yaml2 directories, 7 files

It has charts directory with chart dependencies, but we don’t need it at the moment. Next comes Chart.yaml containing global variables for the chart such as version and description:

These directories and files have the following functions:

  • charts/: Manually managed chart dependencies can be placed in this directory, though it is typically better to use requirements.yaml to dynamically link dependencies.

  • templates/: This directory contains template files that are combined with configuration values (from values.yaml and the command line) and rendered into Kubernetes manifests. The templates use the Go programming language’s template format.

  • Chart.yaml: A YAML file with metadata about the chart, such as chart name and version, maintainer information, a relevant website, and search keywords.

  • LICENSE: A plaintext license for the chart.

  • README.md: A readme file with information for users of the chart.

  • requirements.yaml: A YAML file that lists the chart’s dependencies.

  • values.yaml: A YAML file of default configuration values for the chart.

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