Book Image

The Kubernetes Operator Framework Book

By : Michael Dame
1 (1)
Book Image

The Kubernetes Operator Framework Book

1 (1)
By: Michael Dame

Overview of this book

From incomplete collections of knowledge and varying design approaches to technical knowledge barriers, Kubernetes users face various challenges when developing their own operators. Knowing how to write, deploy, and pack operators makes cluster management automation much easier – and that's what this book is here to teach you. Beginning with operators and Operator Framework fundamentals, the book delves into how the different components of Operator Framework (such as the Operator SDK, Operator Lifecycle Manager, and OperatorHub.io) are used to build operators. You’ll learn how to write a basic operator, interact with a Kubernetes cluster in code, and distribute that operator to users. As you advance, you’ll be able to develop a sample operator in the Go programming language using Operator SDK tools before running it locally with Operator Lifecycle Manager, and also learn how to package an operator bundle for distribution. The book covers best practices as well as sample applications and case studies based on real-world operators to help you implement the concepts you’ve learned. By the end of this Kubernetes book, you’ll be able to build and add application-specific operational logic to a Kubernetes cluster, making it easier to automate complex applications and augment the platform.
Table of Contents (16 chapters)
1
Part 1: Essentials of Operators and the Operator Framework
4
Part 2: Designing and Developing an Operator
9
Part 3: Deploying and Distributing Operators for Public Use

Summary

In this chapter, we used the Prometheus Operator as an example to apply many of the concepts covered throughout the book. This Operator makes a good example because, aside from serving a common need by managing a popular application, it is actually one of the earliest Operators (having published its first release, v0.1.1, in December 2016). This predates the formalized Operator Framework, which developers can benefit from today, explaining idiosyncrasies such as its lack of Operator SDK libraries, but demonstrating the influence of early development decisions in the design of the Operator Framework.

At the beginning of this chapter, we gave a brief overview of Prometheus itself. This gave us a foundational understanding of the use case for a Prometheus Operator, particularly regarding the installation and configuration of Prometheus. This laid the groundwork to understand what the Prometheus Operator does to alleviate these pain points. By examining the CRDs it uses and...