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
About the Author
About the Reviewer

Looking at each function

The file server that we will be writing will be based on SFTP. Because SFTP calls can be expensive to make, we will use a caching implementation that relies on a popular Python library called Paramiko to retrieve files. For simplicity, we will only allow one SFTP server to be configured, but if you find yourself using this module, you may want to consider allowing multiple endpoints to be configured.

Setting up our module

Before we go over the functions that are used, we start setting up the module itself. We will implement a few functions that provide objects that we will use throughout the rest of our module:

The backend for serving files from an SFTP account.

To enable, add ``sftp`` to the :conf_master:`fileserver_backend` option in the
Master config file.

.. code-block:: yaml

      - sftp

Each environment is configured as a directory inside the SFTP account. The name
of the directory must match the name of the environment.

.. code...