{
    "hosts": ["overcloud-novacompute-1.opnfvlf.org",
              "overcloud-novacompute-2.opnfvlf.org",
              "overcloud-novacompute-3.opnfvlf.org"],
    "state": "MAINTENANCE",
    "maintenance_at": "2018-02-28 06:06:03",
    "metadata": {"openstack_release": "Queens"},
    "workflow": "default",
    "download": ["https://my.sw.upgrades.com/SW1.tar.gz",
                 "https://my.sw.upgrades.com/ESW1.tar.gz",
                 "https://my.sw.upgrades.com/plugins1.tar.gz"],
    "actions": [
        {"plugin": "prepare", "type": "pre"},
        {"plugin": "esw_upgrade", "type": "host", "metadata": {"upgrade": "ESW1"}},
        {"plugin": "os_upgrade", "type": "host", "metadata": {"upgrade": "SW1"}},
        {"plugin": "finalize", "type": "post"}]
}