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

FAQs about Operator design, CRDs, and APIs

These questions cover information about an Operator's design, including approaches to developing an Operator and how Operators can function within a Kubernetes cluster. The topics in this section were introduced in Chapter 2, Understanding How Operators Interact with Kubernetes, and Chapter 3, Designing an Operator – CRD, API, and Target Reconciliation.

How does an Operator interact with Kubernetes?

Operators interact with Kubernetes through event-triggered continuous monitoring of the cluster's state, wherein the Operator attempts to reconcile the current state with the desired state as specified by a user. From a technical standpoint, it does so through a standard set of Kubernetes client libraries that allow it to list, get, watch, create, and update Kubernetes resources.

What cluster resources does an Operator act on?

An Operator can act on any resource that is accessible through the Kubernetes API (and that...