Manage Trello webhooks

setup_trello_hooks.py

'''
Script to manage Trello hooks

This script is used to manage Trello hooks. It has sub-commands to create, list
and delete webhooks. It uses two environment variables to authenticate with
Trello: TRELLO_TOKEN and TRELLO_KEY.

Tests:

    To run the tests::

        nosetests test_setup_trello_hooks.py

Examples:

    Creating a new webhook::

        $ python setup_trello_hooks.py create 57e97628d89b38b11b165167 \
          "https://example.com"
        {
            "active": true,
            "idModel": "57e97628d89b38b11b165167",
            "callbackURL": "https://example.com",
            "id": "58d1c4ba2ddf6661ccaf59bd",
            "description": "PNDA PLZ Review Board Webhook"
        }

    List current webhooks::

        $ python setup_trello_hooks.py list
        [
            {
                "active": true,
                "idModel": "57e97628d89b38b11b165167",
                "callbackURL": "http://example.com",
                "id": "58d1c35f4e2c3dc25b9726ab",
                "description": "PNDA PLZ Review Board Webhook"
            }
        ]

    Delete webhook::

        $ python setup_trello_hooks.py delete 58d1c35f4e2c3dc25b9726ab
        {
            "_value": null
        }
'''
from __future__ import print_function
import argparse
import json
import os
import requests

URL = "https://api.trello.com/1/tokens/{trello_token}/webhooks/"


def list_webhooks(url, querystring):
    '''
    List existing webhooks

    Args:
        url (str): url for the Trello API
        querystring (dict): used to pass Trello API key
    Returns:
        requests.models.Response: response object which contains a
        server's response to an HTTP request.
    '''
    return requests.request("GET", url, params=querystring)


def create_webhook(url, querystring, trello_backlog_list_id, callback_url):
    '''
    Delete an existing webhook

    Args:
        url (str): url for the Trello API
        querystring (dict): used to pass Trello API key
        trello_backlog_list_id (str): ID for the webhook to be deleted
        callback_url (str): URL for the AWS lambda
    Returns:
        requests.models.Response: response object which contains a
        server's response to an HTTP request.
    '''
    headers = {
        'content-type': "application/json",
    }

    payload = {
        "description": "PNDA PLZ Review Board Webhook",
        "callbackURL": callback_url,
        "idModel": trello_backlog_list_id,
    }

    return requests.request(
        "POST",
        url,
        data=json.dumps(payload),
        headers=headers,
        params=querystring)


def delete_webhook(url, querystring, webhook_id):
    '''
    Delete an existing webhook

    Args:
        url (str): url for the Trello API
        querystring (dict): used to pass Trello API key
        webhook_id (str): ID for the webhook to be deleted
    Returns:
        requests.models.Response: response object which contains a
        server's response to an HTTP request.
    '''
    return requests.request(
        "DELETE", url + webhook_id, params=querystring)


def main(argv=None):
    '''
    Main function to parse arguements and load environment variables
    '''

    parser = argparse.ArgumentParser(
        description='tool for managing Trello webhooks')
    parser.add_argument(
        '--trello-key',
        default=os.environ.get('TRELLO_KEY', None),
        help='Trello API Key (Can also be specified as environment variable)')
    parser.add_argument(
        '--trello-token',
        default=os.environ.get('TRELLO_TOKEN', None),
        help='Trello API Token (Can also be specified as environment variable)')

    subparsers = parser.add_subparsers(
        help='available sub-commands', dest='subcommand')
    subparsers.add_parser('list', help='list webhooks')

    create_parser = subparsers.add_parser('create', help='create new webhook')
    create_parser.add_argument('list_id', help='ID for Backlog list in Trello')
    create_parser.add_argument(
        'callback_url', help='Callback URL for AWS Lambda function')

    delete_parser = subparsers.add_parser('delete', help='delete webhook')
    delete_parser.add_argument('webhook_id', help='ID of Trello Webhook')

    args = parser.parse_args(argv)

    if not args.trello_key or not args.trello_token:
        exit(parser.print_usage())

    querystring = {"key": args.trello_key}

    if args.subcommand == 'list':
        response = list_webhooks(
            URL.format(trello_token=args.trello_token), querystring)
    elif args.subcommand == 'create':
        response = create_webhook(
            URL.format(trello_token=args.trello_token),
            querystring,
            args.list_id,
            args.callback_url)
    elif args.subcommand == 'delete':
        response = delete_webhook(
            URL.format(trello_token=args.trello_token),
            querystring,
            args.webhook_id)

    print(json.dumps(response.json(), indent=4))


if __name__ == '__main__':
    main()