Custom saltstack grain to identify the redis version

redis.py

# -*- coding: utf-8 -*-

import salt.utils

# Solve the Chicken and egg problem where grains need to run before any
# of the modules are loaded and are generally available for any usage.
import salt.modules.cmdmod

def redis_version():
    '''
    Return version of redis-cli by `redis-cli --version`:

    Version output:
    ---------
        $ redis-cli --version
        redis-cli 2.8.14
    ---------
    '''

    # Determine redis binary
    redis = salt.utils.which('redis-cli')
    if not redis:
        return {}

    # Get the version string from redis
    try:
        redis_version = salt.modules.cmdmod._run_quiet('{0} --version'.format(redis)).replace('redis-cli', '').strip()
    except OSError:
        return {}

    result = {
        'redis_version': redis_version
    }

    return result


if __name__ == '__main__':
    print redis_version()