ansible dynamic inventory from environment vars

envar2inv.py

#!/usr/bin/env python

'''
This file is an ansible dynamic inventory script used to help discover
inventory from environment variables

'''

import json
from os import environ


def gen_inv():

    # look for these words in the environment variable name
    triggers = ['_SERVER', '_HOST']

    # default inventory json
    inv = {
        '_meta': {
            'hostvars': {}
        }
    }

    # discover the inventory
    [inv.update({k: v.split()}) for k, v in environ.items() if
        any([t in k for t in triggers])]

    # return
    print json.dumps(inv, sort_keys=True, indent=2)

if __name__ == '__main__':
    gen_inv()