clone-service

#!/usr/bin/env python
import argparse

import boto3


def clone(client, source_elb_names, dest_elb_names):
    describe_elb = client.describe_load_balancers(LoadBalancerNames=source_elb_names)
    tags = client.describe_tags(LoadBalancerNames=source_elb_names)["TagDescriptions"][0]["Tags"]

    attributes = client.describe_load_balancer_attributes(LoadBalancerName=source_elb_names[0])[
        "LoadBalancerAttributes"]

    descriptor = describe_elb["LoadBalancerDescriptions"][0]

    listeners = []

    for listener in descriptor["ListenerDescriptions"]:
        listeners.append(listener["Listener"])

    client.create_load_balancer(LoadBalancerName=dest_elb_names[0],
                                Listeners=listeners,
                                Subnets=descriptor["Subnets"],
                                SecurityGroups=descriptor["SecurityGroups"],
                                Scheme=descriptor["Scheme"])

    client.configure_health_check(LoadBalancerName=dest_elb_names[0], HealthCheck=descriptor["HealthCheck"])
    client.modify_load_balancer_attributes(LoadBalancerName=dest_elb_names[0],
                                           LoadBalancerAttributes=attributes)

    if len(tags) > 0:
        client.add_tags(LoadBalancerNames=dest_elb_names, Tags=tags)


parser = argparse.ArgumentParser()
parser.add_argument("--profile", type=str, help="AWS Profile")
parser.add_argument("--cluster", type=str, required=True, help="ECS cluster name")
parser.add_argument("--dest-cluster", type=str, help="Destination ECS cluster name")
parser.add_argument("--service", type=str, required=True, help="ECS service name")
parser.add_argument("--dest-name", type=str, required=True, help="Destination ECS service name")
args = parser.parse_args()

dest_cluster = args.dest_cluster if args.dest_cluster else args.cluster

session = boto3.Session(profile_name=args.profile)
client = session.client('ecs')
elbclient = session.client('elb')

services = client.describe_services(cluster=args.cluster, services=[args.service])
if len(services["services"]) == 0:
    raise Exception("Service {0} not found in cluster {1}".format(args.service, args.cluster))

service = services["services"][0]

if len(service["loadBalancers"]) == 0:
    raise Exception(
        "Service {0} in cluster {1} does not have Load Balancers assigned".format(args.service, args.cluster))

elb_source = service["loadBalancers"][0]
elb_name_source = elb_source["loadBalancerName"]
elb_name_dest = args.dest_name
service_name_dest = args.dest_name
clone(elbclient, [elb_name_source], [elb_name_dest])
print "ELB {0} copied from {1}".format(elb_name_dest, elb_name_source)

service = client.create_service(cluster=dest_cluster, serviceName=service_name_dest,
                                taskDefinition=service["taskDefinition"],
                                desiredCount=0, role=service["roleArn"],
                                loadBalancers=[
                                    {
                                        'loadBalancerName': elb_name_dest,
                                        'containerName': elb_source["containerName"],
                                        'containerPort': elb_source["containerPort"]
                                    },
                                ], deploymentConfiguration=service["deploymentConfiguration"])

print "Service {0} created with ELB {1}".format(service_name_dest, elb_name_dest)