Delete Default VPC Resources

Delete_Default_VPC_Resources.py

#!/usr/bin/env python
import argparse
import boto3
import sys
from botocore.exceptions import ClientError

EXCLUDE_REGIONS = [ 'us-gov-west-1', 'cn-north-1' ] # don't try to delete VPCs in these regions

class DefaultVpc(object):

    def __init__(self, region, args):
        self.client = boto3.client(
            'ec2',
            region_name=region,
            aws_access_key_id=args.aws_access_key_id,
            aws_secret_access_key=args.aws_secret_access_key,
            aws_session_token=args.aws_session_token
        )

    def get(self, resource='vpc'):

        if resource == 'vpc':
            return self.client.describe_vpcs(
                Filters=[{
                    'Name' : 'isDefault',
                    'Values' : [
                        'true',
                    ]
                }]
            )['Vpcs']
        elif resource == 'igw':
            return self.client.describe_internet_gateways(
                Filters=[{
                    'Name' : 'attachment.vpc-id',
                    'Values' : [
                        self.get()[0]['VpcId'],
                    ]
                }]
            )['InternetGateways']
        elif resource == 'subnets':
            return self.client.describe_subnets(
                Filters=[{
                    'Name' : 'defaultForAz',
                    'Values' : [
                        'true',
                    ]
                }]
            )['Subnets']

    def delete(self):
        vpc = self.get()

        if len(vpc) > 0:
            # detach and delete internet gateway
            igw = self.get('igw')
            
            if len(igw) > 0:
                sys.stdout.write("Detaching Internet GateWay(%s) from VPC(%s)... " %(igw[0]['InternetGatewayId'], vpc[0]['VpcId']))
                try:
                    self.client.detach_internet_gateway(
                        InternetGatewayId=igw[0]['InternetGatewayId'],
                        VpcId=vpc[0]['VpcId']
                    )
                except ClientError as e:
                    sys.stdout.write("failed.\n")
                    sys.stderr.write(e)
                    sys.exit(1)
                else:
                    sys.stdout.write("done.\n")

                sys.stdout.write("Deleting Internet GateWay(%s)... " %igw[0]['InternetGatewayId'])
                try:
                    self.client.delete_internet_gateway(
                        InternetGatewayId=igw[0]['InternetGatewayId']
                    )
                except ClientError as e:
                    sys.stdout.write("failed.\n")
                    sys.stderr.write(e)
                    sys.exit(2)
                else:
                    sys.stdout.write("done.\n")

            # delete subnets
            subnets = self.get('subnets')

            if len(subnets) > 0:
                for subnet in subnets:
                    sys.stdout.write("Deleting Subnet(%s)... " %subnet['SubnetId'])
                    try:
                        self.client.delete_subnet(
                            SubnetId=subnet['SubnetId']
                        )
                    except ClientError as e:
                        sys.stdout.write("failed.\n")
                        sys.stderr.write(e)
                        sys.exit(3)
                    else:
                        sys.stdout.write("done.\n")

            # delete vpc
            sys.stdout.write("Deleting VPC(%s)... " %vpc[0]['VpcId'])
            try:
                self.client.delete_vpc(
                    VpcId=vpc[0]['VpcId']
                )
            except ClientError as e:
                sys.stdout.write("failed.\n")
                sys.stderr.write(e)
                sys.exit(4)
            else:
                sys.stdout.write("done.\n")

            return

        sys.stdout.write('No Default VPC found...\n')
        return


def get_vpc_regions():
    ec2_client = boto3.client('ec2', region_name='us-east-1')
    return map( lambda region: region['RegionName'], ec2_client.describe_regions()['Regions'] )


def get_cli_args():
    parser = argparse.ArgumentParser()
    parser.add_argument('--aws-access-key-id', action = 'store', required=False, metavar='AWS_ACCESS_KEY_ID', dest='aws_access_key_id', default=None, help='AWS access key.' )
    parser.add_argument('--aws-secret-access-key', action = 'store', required=False, metavar='AWS_SECRET_ACCESS_KEY', dest='aws_secret_access_key', default=None, help='AWS secret key.' )
    parser.add_argument('--aws-session-token', action = 'store', required=False, metavar='AWS_SESSION_TOKEN', dest='aws_session_token', default=None, help='Specify a session token if you are using temporary security credentials.' )
    parser.add_argument('--dry-run', action = 'store_true', required=False, dest='dry_run', default=False, help='.' )
    
    group = parser.add_mutually_exclusive_group(required=True)
    group.add_argument('--all-regions', action = 'store_true', dest='all_regions', help='AWS access key.' )
    group.add_argument('--region', action = 'store', metavar='AWS_REGION_NAME', dest='region', help='AWS region.' )
    return parser.parse_args()


if __name__ == '__main__':
    args = get_cli_args()

    if args.all_regions:
        regions = get_vpc_regions()
    else:
        regions = [ args.region ]

    for region in regions:
        sys.stderr.write("Deleting Default VPC in Region: {}\n".format(region))
        vpc = DefaultVpc(region, args)
        vpc.delete()