Book Image

Chef Cookbook - Third Edition

By : Matthias Marschall
Book Image

Chef Cookbook - Third Edition

By: Matthias Marschall

Overview of this book

Chef is a configuration management tool that lets you automate your more cumbersome IT infrastructure processes and control a large network of computers (and virtual machines) from one master server. This book will help you solve everyday problems with your IT infrastructure with Chef. It will start with recipes that show you how to effectively manage your infrastructure and solve problems with users, applications, and automation. You will then come across a new testing framework, InSpec, to test any node in your infrastructure. Further on, you will learn to customize plugins and write cross-platform cookbooks depending on the platform. You will also install packages from a third-party repository and learn how to manage users and applications. Toward the end, you will build high-availability services and explore what Habitat is and how you can implement it.
Table of Contents (15 chapters)
Chef Cookbook - Third Edition
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
Index

Installing Ruby gems and using them in recipes


Recipes are plain Ruby files. It is possible to use all of Ruby's language features inside your recipes. Most of the time, the built-in Ruby functionality is enough but sometimes you might want to use additional Ruby gems. Connecting to an external application via an API or accessing a MySQL database from within your recipe are examples of where you will need Ruby gems inside your recipes.

Chef lets you install Ruby gems from within a recipe, so that you can use them later.

Getting ready

Make sure you have a cookbook called my_cookbook and that the run_list of your node includes my_cookbook, as described in the Creating and using cookbooks recipe in Chapter 1, Chef Infrastructure.

How to do it…

Let's see how we can use the ipaddress gem in our recipe:

  1. Edit the default recipe of your cookbook, installing a gem to be used inside the recipe:

    mma@laptop:~/chef-repo $ subl cookbooks/my_cookbook/recipes/default.rb
         chef_gem 'ipaddress' do
           compile_time...