Python helper for a Terraform External provider

TfExternal.py

import json


class TfExternal(object):
    """Wrap Terraform External provider."""

    @staticmethod
    def query_args(obj):
        """Load json object from stdin."""
        return {} if obj.isatty() else json.load(obj)

    @staticmethod
    def out_json(result):
        """Print result to stdout."""
        print(json.dumps(result))

Usage example:

import sys

from utils import TfExternal  # presumes the class is saved in utils.py


def main(**kwargs):
    # `kwargs` contains the query args passed from Terraform
    # Run your custom logic
    result = kwargs
    return result


if __name__ == "__main__":
    tfe = TfExternal()
    args = tfe.query_args(sys.stdin)
    sys.exit(tfe.out_json(main(**args)))