Book Image

Learn Helm

By : Andrew Block, Austin Dewey
Book Image

Learn Helm

By: Andrew Block, Austin Dewey

Overview of this book

Containerization is currently known to be one of the best ways to implement DevOps. While Docker introduced containers and changed the DevOps era, Google developed an extensive container orchestration system, Kubernetes, which is now considered the frontrunner in container orchestration. With the help of this book, you’ll explore the efficiency of managing applications running on Kubernetes using Helm. Starting with a short introduction to Helm and how it can benefit the entire container environment, you’ll then delve into the architectural aspects, in addition to learning about Helm charts and its use cases. You’ll understand how to write Helm charts in order to automate application deployment on Kubernetes. Focused on providing enterprise-ready patterns relating to Helm and automation, the book covers best practices for application development, delivery, and lifecycle management with Helm. By the end of this Kubernetes book, you will have learned how to leverage Helm to develop an enterprise pattern for application delivery.
Table of Contents (15 chapters)
Section 1: Introduction and Setup
Section 2: Helm Chart Development
Section 3: Adanced Deployment Patterns
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Creating a Helm operator

In this section, we will write a Helm-based operator that will be used to install the Guestbook Helm chart created in Chapter 5, Building Your First Helm Chart. This chart can be seen under the guestbook/ folder of the Packt repository (

An operator is built as a container image that contains the control loop logic to maintain an application. The following diagram demonstrates how the Guestbook Operator will function once it is deployed:

Figure 8.1 – Guestbook Operator workflow

The Guestbook Operator will constantly watch for changes to Guestbook CRs. When a Guestbook CR is created, the Guestbook Operator will install the Guestbook chart you created in Chapter 5, Building Your First Helm Chart. Conversely, if the Guestbook CR is deleted, the Guestbook Operator will remove the Guestbook Helm chart.

With an understanding of how...