Get up to speed with Helm, the preeminent package manager for the Kubernetes container orchestration system. This practical guide shows you how to efficiently create, install, and manage the applications running inside your containers. Helm maintainers Matt Butcher, Matt Farina, and Josh Dolitsky explain how this package manager fits into the Kubernetes ecosystem and provide an inside look at Helm's design and best practices.

More than 70% of the organizations that work with Kubernetes use Helm today. While the Helm community provides thousands of packages, or charts, to help you get started, this book walks developers and DevOps engineers through the process of creating custom charts to package applications. If you have a working understanding of Kubernetes, you're ready to go.

• Explore primary features including frequently used Helm commands
• Learn how to build and deploy Helm charts from scratch
• Use Helm to manage complexity and achieve repeatable deployments
• Package an application and its dependencies for easy installation
• Manage the entire lifecycle of applications on Kubernetes
• Explore ways to extend Helm to add features and functionality
• Learn features for testing, handling dependencies, and providing security

About this book:

Helm is the package manager for Kubernetes, the popular open source container management platform.

Package managers make platforms more accessible to those who use them. In order to use a platform like Kubernetes, you need to run software on it, and much of that software will be off-the-shelf or shared. Package managers like Helm enable you to install and start using the software quickly without needing to figure out how to make it run or run well on the platform, because it has already been packaged up in an easy-to-use manner.

If you have software you want to share with others, package managers make it easy to do. Platforms are more useful when there is a wide variety of software to run on them; open source projects and companies both like to make their software easy to install on the platforms it runs on, and Helm makes this possible for Kubernetes.

Package managers aren’t just for sharing and consuming others’ software, however. They are often an integral part of other systems, such as DevOps tooling, and they are used as a building block.

Virtually every modern platform has a package manager. Operating systems, programming languages, and cloud platforms all have package managers of some form.

In this book you will learn about Helm, which provides modern package management for Kubernetes, and the packages, called charts, that you can use with it. You will learn how to use Helm, how to create packages, and how to share those packages with other platforms.

Why We Wrote This Book

We, the authors, are maintainers of Helm, so we set out to write a book to help those who have questions about it. We didn’t just want to supply the technical details that are often found in the documentation; we wanted to provide context and insight into what Helm does and why.

Who Should Read This Book

There are a few situations where you will find this book useful. If you’re new to Kubernetes or want to learn how to install off-the-shelf applications, this book will help you learn how to do that with Helm. It is much easier and faster to install applications through Helm than it is to learn how to do so by hand with Kubernetes. If you work for a company (or a project) that wants to distribute your applications to Kubernetes users in an easy-to-consume manner, this book will teach you how to do that with Helm. Being able to quickly install your application makes getting started easier, and Helm can help you with that.

This book is also for DevOps professionals who want to learn to use Kubernetes package management as part of their DevOps toolchains. Helm provides powerful and advanced features that can be used as building blocks for other automation. These have been used to deploy large and complex applications onto Kubernetes, and this book will teach you how to leverage those features.

About the Author

Matt Butcher is a co-founder/creator of the Helm project. He leads a team of open source engineers at Microsoft Azure. Matt is also the co-creator of the Illustrated Children’s Guide to Kubernetes (with Karen Chu) and has authored eight other books (two with Matt Farina). He holds a Ph.D. in philosophy. When not coding, he enjoys drinking great coffee or hiking in the Colorado Rockies.

Matt Farina is a maintainer on the Helm project and has been contributing to open source projects for more than 15 years. He co-founded and co-chairs Kubernetes Apps Special Interest Group (SIG) which focuses on running workloads on Kubernetes. Matt works on the Cloud Native Computing Team at Samsung SDS where he focuses on contributing to open source and applying open source software to new development. He has previously authored two books alongside Matt Butcher. Creative problem solving and helping people are two driving forces for Matt’s work with software.

Josh Dolitsky is a maintainer of the Helm project and founder of the ChartMuseum project. He is the owner and lead engineer of Blood Orange, a software consulting firm specialized in helping with DevOps, CI/CD, and Kubernetes.