(aws/python) find 'blackhole' route tables

get_blackhole_routes.py

import boto3
import click
import logzero
from logzero import logger


class GetRoutesTables:
    def __init__(self, aws_profile: str, aws_region: str = 'ap-northeast-2'):
        self.session = boto3.session.Session(profile_name=aws_profile, region_name=aws_region)

    def get_route_tables(self) -> list:
        """

        :param aws_account:
        :return:
        """
        client = self.session.client('ec2')
        response = client.describe_route_tables()

        return response['RouteTables']

    def get_blackhole_route(self) -> list:
        """

        :return: ['rtb-6f571234,10.10.10.0./26', 'rtb-6f556786,10.11.0.0/21']
        """
        route_tables = self.get_route_tables()

        for route_table in route_tables:
            route_table_id = route_table['RouteTableId']
            logger.debug('route table id: %s', route_table_id)

            blackhole_routes = []
            for route in route_table['Routes']:
                destination_cidr_black = route.get('DestinationCidrBlock', 'N/A')
                state = route['State']

                logger.debug('destination: %s, %s, %s', route_table_id, destination_cidr_black, state)

                if state == 'blackhole':
                    blackhole_routes.append(route_table_id + ', ' + destination_cidr_black)

            return blackhole_routes


@click.command()
@click.option('--aws_profile', required=True)
@click.option('--debug', default=False, is_flag=True)
def main(aws_profile, debug):
    """

    :param aws_profile:
    :param debug:
    """
    if debug:
        logzero.loglevel(logzero.DEBUG)
    else:
        logzero.loglevel(logzero.INFO)

    route_tables = GetRoutesTables(aws_profile)
    blackhole_routes = route_tables.get_blackhole_route()

    print(blackhole_routes)

    return None


if __name__ == '__main__':
    main()

output_sample.md

sample output

$ python get_blackholes.py --aws_profile=default
['rtb-1f371c01, 172.31.0.0/11', 'rtb-1f371c01, 10.18.0.0/11', 'rtb-1f371c01, 10.88.0.0/11', 'rtb-1f371c01, 10.113.0.0/11']

requirements.txt

boto3
click
logzero