Gio.DBusObjectManagerClient not updating

[Hayden Lau <HaydenL aercoustics com>]

Hello,

I understand this is a dev mailing list, but I’m not sure where to post this question otherwise.

I’m attempting to write an application that interacts with UDisks2 over  DBus with PyGObject. However, I’m 
finding that after instantiating the  proper Gio.DBusObjectManagerClient, I seem to be unable to get updates  
on the ObjectManager’s state. Am I missing something? The only example  code that I could find that had 
similar functionality was in udiskie (https://github.com/coldfix/udiskie),  but that application uses 
Gio.DBusProxy directly. Is that the  recommended approach? My (non-working) proof of concept code pasted  
below. It prints the initial set of objects reported by the  ‘org.freedesktop.UDisks2’ object manager, but 
does not print changes  (either via signal or polling) when disks are added or removed.

I am using the version of PyGObject that comes packaged with Ubuntu 16.04 LTS, 3.20.0, along with the 
versions of DBus and Glib, etc that also come with the OS. (https://packages.ubuntu.com/xenial/python3-gi)

Thank you,
Hayden Lau

========================
from time import sleep
import gi
gi.require_version('Gio', '2.0')
from gi.repository import Gio

udisks2 = Gio.DBusObjectManagerClient.new_for_bus_sync(
    Gio.BusType.SYSTEM, 
    Gio.DBusObjectManagerClientFlags.NONE,
    'org.freedesktop.UDisks2',
    '/org/freedesktop/UDisks2',
    None,
    None,
    None
)

def new_obj_handler(obj):
    print('New Object: ', obj)

def new_iface_handler(obj):
    print('New Interface: ', obj)

def get_paths(objmgr):
    return [obj.get_object_path() for obj in objmgr.get_objects()]

udisks2.connect('interface-added', new_iface_handler)
udisks2.connect('object-added', new_obj_handler)

paths = []
while(True):
    if paths != get_paths(udisks2):
        paths = get_paths(udisks2)
        print(paths)
    sleep(1)