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

Chapter 1: Introducing the Operator Framework

Managing a Kubernetes cluster is hard. This is partly due to the fact that any microservice architecture is going to be inherently based on the interactions of many small components, each introducing its own potential point of failure. There are, of course, many benefits to this type of system design, such as graceful error handling thanks to the separation of responsibilities. However, diagnosing and reconciling such errors requires significant engineering resources and a keen familiarity with an application's design. This is a major pain point for project teams who migrate to the Kubernetes platform.

The Operator Framework was introduced to the Kubernetes ecosystem to address these problems. This chapter will go over a few general topics to give a broad overview of the Operator Framework. The intent is to provide a brief introduction to the Operator Framework, the problems it solves, how it solves them, and the tools and patterns it provides to users. This will highlight key takeaways for the goals and benefits of using Operators to help administrate a Kubernetes cluster. These topics include the following:

  • Managing clusters without Operators
  • Introducing the Operator Framework
  • Developing with the Operator software development kit (SDK)
  • Managing Operators with the Operator Lifecycle Manager (OLM)
  • Distributing Operators on OperatorHub.io
  • Defining Operator functions with the Capability Model
  • Using Operators to manage applications