Handy script to help migrate all Mesos Marathon apps from 1 cluster to another. Can use either a Marathon URI or a local file location for both source & destination sinks. Works on both Python2 & Python3.

marathon_migrate.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import argparse
from os import environ
from json import load, loads, dumps
from urlparse import urlparse
try:
    from urllib.request import urlopen, Request
    from urllib.error import HTTPError
except ImportError:
    from urllib2 import urlopen, Request, HTTPError

class PutRequest(Request):
    def __init__(self, *args, **kwargs):
        return Request.__init__(self, *args, **kwargs)

    def get_method(self, *args, **kwargs):
        return 'PUT'


def read(source_marathon):
    source_scheme = urlparse(source_marathon).scheme
    if not source_scheme or source_scheme == 'file':
        with open(source_marathon) as json_data:
            apps = load(json_data)
            return apps
    else:
        response = urlopen('{}/v2/apps'.format(source_marathon))
        apps = loads(response.read())
        return apps


def write(data, dest_marathon):
    dest_scheme = urlparse(dest_marathon).scheme
    if not dest_scheme or dest_scheme == 'file':
        with open(dest_marathon, 'w') as json_dump:
            json_dump.write(dumps(data, indent=4))
    else:
        current_apps = data.get('apps', [])
        for (index, app) in enumerate(current_apps):
            keys_to_remove = ['version', 'versionInfo', 'uris']
            new_app = {x: app[x] for x in app if x not in keys_to_remove}
            print('Force deploying app #{} of {} ({}) to destination Marathon... '.format(index + 1, len(current_apps), new_app.get('id'))),
            req = PutRequest('{}/v2/apps?force=true'.format(dest_marathon), headers={'Content-Type': 'application/json'}, data=dumps([new_app]))
            try:
                response = urlopen(req)
                print('[OK]')
            except HTTPError as error:
                print('[FAILED] ({})'.format(error.code))


def copy_apps(source_marathon, dest_marathon):
    print('Copying apps from {} to {}'.format(source_marathon, dest_marathon))
    apps = read(source_marathon)
    write(apps, dest_marathon)

if __name__ == '__main__':
    parser = argparse.ArgumentParser(description='Copy all apps from 1 Marathon cluster to another', epilog='You can also use local file locations for both source & destination.')
    parser.add_argument('source', help='Source Marathon to copy apps from. Can also be a file location.', type=str)
    parser.add_argument('dest', help='Destination Marathon to deploy copied apps to. Can also be a file location.', type=str)
    args = parser.parse_args()
    copy_apps(args.source, args.dest)