Book Image

Argo CD in Practice

By : Liviu Costea, Spiros Economakis
Book Image

Argo CD in Practice

By: Liviu Costea, Spiros Economakis

Overview of this book

GitOps follows the practices of infrastructure as code (IaC), allowing developers to use their day-to-day tools and practices such as source control and pull requests to manage apps. With this book, you’ll understand how to apply GitOps bootstrap clusters in a repeatable manner, build CD pipelines for cloud-native apps running on Kubernetes, and minimize the failure of deployments. You’ll start by installing Argo CD in a cluster, setting up user access using single sign-on, performing declarative configuration changes, and enabling observability and disaster recovery. Once you have a production-ready setup of Argo CD, you’ll explore how CD pipelines can be built using the pull method, how that increases security, and how the reconciliation process occurs when multi-cluster scenarios are involved. Next, you’ll go through the common troubleshooting scenarios, from installation to day-to-day operations, and learn how performance can be improved. Later, you’ll explore the tools that can be used to parse the YAML you write for deploying apps. You can then check if it is valid for new versions of Kubernetes, verify if it has any security or compliance misconfigurations, and that it follows the best practices for cloud-native apps running on Kubernetes. By the end of this book, you’ll be able to build a real-world CD pipeline using Argo CD.
Table of Contents (15 chapters)
1
Part 1: The Fundamentals of GitOps and Argo CD
4
Part 2: Argo CD as a Site Reliability Engineer
7
Part 3: Argo CD in Production

YAML and Kubernetes Manifests

We can’t talk about GitOps and Argo CD and not have a chapter dedicated to YAML Ain’t Markup Language (YAML). We wrote a lot of YAML in all the chapters so far, and I expect you will write a lot more if you start using Argo CD, so we are going to check some ways to statically analyze it. First, we will take a close look at the most common templating engines, Helm and Kustomize, and how we can use them in order to generate the final manifests our GitOps engine is going to apply. Then, we will look at a tool that can validate the manifests we will be creating against the Kubernetes schema. After this, we will check the most common practices to enforce on the manifests, which helps us to introduce stability and predictability into the system. And we will finish the chapter by introducing one of the most interesting tools to use in pipelines in order to perform extended checks over YAML—conftest, which allows you to write your own rules...