Book Image

Mastering Ansible, 4th Edition - Fourth Edition

By : James Freeman, Jesse Keating
Book Image

Mastering Ansible, 4th Edition - Fourth Edition

By: James Freeman, Jesse Keating

Overview of this book

Ansible is a modern, YAML-based automation tool (built on top of Python, one of the world’s most popular programming languages) with a massive and ever-growing user base. Its popularity and Python underpinnings make it essential learning for all in the DevOps space. This fourth edition of Mastering Ansible provides complete coverage of Ansible automation, from the design and architecture of the tool and basic automation with playbooks to writing and debugging your own Python-based extensions. You'll learn how to build automation workflows with Ansible’s extensive built-in library of collections, modules, and plugins. You'll then look at extending the modules and plugins with Python-based code and even build your own collections — ultimately learning how to give back to the Ansible community. By the end of this Ansible book, you'll be confident in all aspects of Ansible automation, from the fundamentals of playbook design to getting under the hood and extending and adapting Ansible to solve new automation challenges.
Table of Contents (18 chapters)
Section 1: Ansible Overview and Fundamentals
Section 2: Writing and Troubleshooting Ansible Playbooks
Section 3: Orchestration with Ansible

How to port legacy playbooks to Ansible 4.3 (a primer)

No two Ansible playbooks (or roles or templates for that matter) are alike, and they vary in complexity from the simple to the intricate and complex. However, they are all important to their authors and users, and with all the major changes that were made in the transition from Ansible 2.9 through to 4.0, this book would not be complete without a primer on how to port your code to the newer Ansible versions.

Before we get too deep into this subject, let's look at an example. In the first ever edition of this book, written in 2015 about Ansible version 1.9, an example appeared that renders a Jinja2 template using a small Ansible playbook. We will still learn about an updated version of this code in Chapter 6, Unlocking the Power of Jinja2 Templates, of this book, but for now let's look at the original code. The template, called demo.j2, looks like this:

setting = {{ setting }} 
{% if feature.enabled %} 
feature ...