route53-register

#!/usr/bin/env python
import logging
import argparse
import ConfigParser

import boto.ec2
import boto.route53
from boto.route53.record import ResourceRecordSets

config = ConfigParser.SafeConfigParser({
    'region_name': 'us-west-2',
    'environment': None
})


def list_servers():
    region_name = config.get('general', 'region_name')
    environment = config.get('general', 'environment')
    server_name = config.get('general', 'server_name')
    filter = {
        "tag:name": server_name,
    }
    if environment is not None:
        filter['tag:environment'] = environment

    logging.info('List instances filtered by name: {0}'.format(
        server_name
    ))
    logging.info('List instances filtered by environment: {0}'.format(
        environment
    ))

    ec2 = boto.ec2.connect_to_region(region_name=region_name)
    logging.info('EC2 Connected')
    logging.info('Getting only instances tagged with:{0}'.format(filter))
    instances = ec2.get_only_instances(filters=filter)
    logging.info('Found {0} instances'.format(len(instances)))
    logging.info('List of instances:')
    for instance in instances:
        logging.info('  instance:{0} '.format(instance.id))
    return instances


def register_server():
    instances = list_servers()
    if len(instances) is 1 and instances[0].state == 'running':
        instance = instances[0]
        region_name = config.get('general', 'region_name')
        zone_id = config.get('route53', 'zone_id')
        host_name = config.get('route53', 'host_name')
        logging.info('instance:{0}  public dns name:{1}'.format(
            instance, instance.public_dns_name))
        conn = boto.route53.connect_to_region(region_name=region_name)
        existing_entries = conn.get_all_rrsets(hosted_zone_id=zone_id)

        for item in existing_entries:
            logging.debug(item)

        change = ResourceRecordSets(conn, zone_id)
        change.add_change_record(
            'UPSERT',
            boto.route53.record.Record(
                name=host_name,
                type='CNAME',
                resource_records=[instance.public_dns_name],
                ttl=300)
        )
        change.commit()
        logging.info(
            'instance:{0} w/ public dns name:{1} registered with Zone ID:{2} for host name:{3}'.format(
                instance.id, instance.public_dns_name, zone_id, host_name
            ))
    else:
        logging.info("Couldn't work with list of instances: {0}".format(
            instances
        ))

commands = {
    "list": list_servers,
    "register": register_server
}


if __name__ == '__main__':
    parser = argparse.ArgumentParser(
        description='List instances with a name or register as a Route53 CNAME target',
        prog='mc-manager'
    )
    parser.add_argument('cmd', nargs='?', default='list', choices=commands,
                        help='command to execute [default: %(default)s]')
    parser.add_argument('--log', dest='log_level', default='INFO',
                        help='set Log Level [INFO|DEBUG|WARNING|ERROR]')
    parser.add_argument('--config', dest='config', default='r53.cfg',
                        help='the optional config file [default: %(default)s]')

    args = parser.parse_args()
    logging.basicConfig(level=args.log_level.upper())
    config.read(args.config)

    cmd = args.cmd.lower()
    command = commands.get(cmd)
    if command is None:
        logging.error('Command {0} not understood.'.format(cmd))
    else:
        command()