Book Image

Mastering Puppet 5

By : Ryan Russell-Yates, Jason Southgate
Book Image

Mastering Puppet 5

By: Ryan Russell-Yates, Jason Southgate

Overview of this book

Puppet is a configuration management system and a language written for and by system administrators to manage a large number of systems efficiently and prevent configuration drift. The core topics this book addresses are Puppet's latest features and mastering Puppet Enterprise. You will begin by writing a new Puppet module, gaining an understanding of the guidelines and style of the Puppet community. Following on from this, you will take advantage of the roles and profiles pattern, and you will learn how to structure your code. Next, you will learn how to extend Puppet and write custom facts, functions, types, and providers in Ruby, and also use the new features of Hiera 5. You will also learn how to configure the new Code Manager component, and how to ensure code is automatically deployed to (multiple) Puppet servers. Next, you will learn how to integrate Puppet with Jenkins and Git to build an effective workflow for multiple teams, and use the new Puppet Tasks feature and the latest Puppet Orchestrator language extensions. Finally, you will learn how to scale and troubleshoot Puppet. By the end of the book, you will be able to deal with problems of scale and exceptions in your code, automate workflows, and support multiple developers working simultaneously.
Table of Contents (19 chapters)
Title Page
Dedication
Packt Upsell
Contributors
Preface
Index

Application components


Application components provide the individual pieces of the multi-node application. They are most often defined types (for reusability), but can also consist of classes or even native resources, such as files, in very simple cases. Application components are created by the exportconsume, or require metaparameters that are used in an application declaration. 

Application components are written as general classes or defined types. They follow the same autoload format as all other Puppet code. The manifest for example::app2 would still be located at manifests/example/app2.pp. Application components can explicitly list the values they export and consume in their individual manifests by placing an additional statement at the bottom of the manifests:

class example::app2 (
# $db_host is provided by the consume of the Database
  $db_host,
) {
# Any resources, defined types or class calls in a regular manifest would be placed here.
}
# Note that the consume is outside of the...