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

The final beacon module


When all is said and done, our final beacon module will look like this:

'''
Send events covering nspawn containers

This beacon accepts a list of containers and whether they should be
running or absent:

    .. code-block:: yaml

        beacons:
          nspawn:
            vsftpd: running
            httpd: absent


This file should be saved as salt/beacons/nspawn.py
'''
import time

__virtualname__ = 'nspawn'


def __virtual__():
    '''
    Ensure that systemd-nspawn is available
    '''
    if 'nspawn.list_running' in __salt__:
        return __virtualname__
    return False


def validate(config):
    '''
    Validate the beacon configuration
    '''
    if not isinstance(config, dict):
        return False
    for key in config:
        if config[key] not in ('running', 'absent'):
            return False
    return True


def beacon(config):
    '''
    Scan for nspawn containers and fire events
    '''
    interval = __salt__['config.get']('nspawn_alert_interval...