Book Image

Extending SaltStack

Book Image

Extending SaltStack

Overview of this book

Salt already ships with a very powerful set of tools, but that doesn't mean that they all suit your needs perfectly. By adding your own modules and enhancing existing ones, you can bring the functionality that you need to increase your productivity. Extending SaltStack follows a tutorial-based approach to explain different types of modules, from fundamentals to complete and full-functioning modules. Starting with the Loader system that drives Salt, this book will guide you through the most common types of modules. First you will learn how to write execution modules. Then you will extend the configuration using the grain, pillar, and SDB modules. Next up will be state modules and then the renderers that can be used with them. This will be followed with returner and output modules, which increase your options to manage return data. After that, there will be modules for external file servers, clouds, beacons, and finally external authentication and wheel modules to manage the master. With this guide in hand, you will be prepared to create, troubleshoot, and manage the most common types of Salt modules and take your infrastructure to new heights!
Table of Contents (21 chapters)
Extending SaltStack
Credits
Foreword
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Writing a generic cloud module


We're going to set up a very generic module that uses a direct REST API to communicate with a cloud provider. If you spend a lot of time with different APIs, you'll find the style used here to be very common.

Checking for required configuration

In order to use a cloud provider, you will need a __virtual__() function to check for required configuration, and if necessary, any dependencies. You will also need a function called get_configured_provider(), which checks to make sure that the configuration that is required to connect to your cloud provider (usually authentication at the very least, and sometimes other connection parameters) have been specified. We will also need to define __virtualname__, which contains the name of the driver as Salt Cloud will know it. Let's go ahead and start our cloud module with these:

'''
Generic Salt Cloud module

This module is not designed for any specific cloud provider, but is generic
enough that only minimal changes may be...