Andrew Block - Managing Kubernetes Resources Using Helm: Simplifying how to build, package, and distribute applications for Kubernetes, 2nd Edition

Simplifying how to build, package, and distribute applications for Kubernetes

Andrew Block

Austin Dewey

BIRMINGHAMMUMBAI

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First published: June 2020

Second Edition: September 2022

Production reference: 1070922

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To the open source community for their ongoing support and collaboration.

Andrew Block

To my wife, Lindsey, for her unwavering love and support.

Austin Dewey

This is an enjoyable and informative book about Helm, the Kubernetes Package Manager, from Andrew Block and Austin Block. I do not know the authors personally, but can tell that they have a wealth of knowledge and experience in the subject. Andrew Block recently became the core maintainer of the Helm project, so to him I say: nice to have to you there!

This book is for all levels, from basic to advanced, and everyone will find useful information and tips within it.

This book has three parts, starting with introduction to Kubernetes, and finishing with advanced deployment patterns for Helm.

Part 1 will explain Kubernetes at a high level, alongside the basics of Kubernetes app installation with kubectl. You will then learn what Helm is, and learn about its bases. This part of the book covers how to decompose monolithic apps into smaller applications. You will learn how to setup a local Kubernetes environment, install kubectl and Helm cli, and install, upgrade, and rollback your first application with Helm.

If you are an advanced user, you can skip this part and move straight to Part 2.

Part 2 will take you through Helm charts development, dependency management, and a thorough explanation of all chart templates. This part also covers Helm lifecycle hooks, which allow you to extend helm charts to another level of usefulness. Youll also learn how to publish charts to the Helm repository and OCI registry. Finally, youll learn how to validate charts using helm lint locally and against a live cluster.

I really recommend learning to use the chart testing tool. Making it part of your local and CI process will save you a lot of time, as you wont be looking for chart bugs at the end of your process.

Of course you arent going to write all the Helm charts you need during your normal working life, as there are many Helm charts that have been written by the community or by existing companies. However, understanding how to develop Helm charts will also allow you to use third party charts, modify their values, and even enhance them too. It will also aid you in learning how to provide PRs (pull requests) to the charts git repositories.

This section of the book is extremely valuable if you want to learn how to develop Helm charts, and therefore should not be skipped.

In Part 3, you will learn how to automate Helm releases with CD and GitOps. There is a very detailed explanation of how to do that with Argo CD (which happens to be my favourite GitOps Kubernetes operator as well)

You will also learn about the Operator Framework, which is an advanced topic. This section covers Kubernetes operator bases, how to create Helm operators, and how to manage them with Custom Resources Definitions (CRDs) and Custom Recourses (CRs).

This part of the book also covers Helm security best practices, which is a very important topic. Youll also learn how to verify Helm binaries, how to sign and verify Helm charts, use secure images, and, of course, how to set up charts resources requests and limits. Finally, youll also learn how to handle secrets in Helm charts which is an important feature to know, as at the end Helm releases should be deployed in the most secure way.

Rimantas Mocevicius rimusz

Helm Co-Founder

Author of kubectl: Command-Line Kubernetes in a Nutshell Book

Senior DevOps Engineer at JFrog Ltd (Nasdaq: FROG)

Andrew Block is a core maintainer on the Helm project and a Distinguished Architect at Red Hat. He specializes in the use of continuous integration and continuous delivery methodologies to streamline the delivery process and incorporate security at each stage. He works with organizations to adopt and implement these technologies and concepts within their organization. As an open source enthusiast, Andrew not only has authored several publications, but he is also a contributor to several open source communities and a lead within the sigstore project, which aims at simplifying how software is signed and verified.

Austin Dewey is a DevOps engineer focused on delivering a streamlined developer experience on cloud and container technologies. Austin started his career with Red Hats consulting organization, where he helped drive success at Fortune 500 companies by automating deployments on Red Hats Kubernetes-based PaaS, OpenShift Container Platform. Currently, Austin works at fintech start-up Prime Trust, where he builds automation to scale financial infrastructure and supports developers on Kubernetes and AWS.

Shashikant Bangera is a DevOps architect with 22 years of IT experience. His technical expertise spans across digital transformation, DevOps, the cloud, and containerization. He has helped a wide range of customers, from small, medium, and large businesses, with digital adoption for domains such as banking, e-commerce, and retail. He has architected and implemented enterprise DevOps at a large scale and also contributes to many open source platforms. He has authored and reviewed a number of books on DevOps with Packt. Shashikant has also contributed to lots of blogs on DevOps. He has designed an automated on-demand environment with a set of open source tools that is available on GitHub. You can reach him on Twitter