Python is crazy

README.md

Usage

You'll need dbus running. In a console:

python server.py

In another console:

python client.py

Exposing the bug

In server.py line 32, replace:

bus_name = dbus.service.BusName('org.example.Ui', bus)

With:

dbus.service.BusName('org.example.Ui', bus)

Hypothesis

I'm guessing BusName initializes an object that in its construction has the side effect of publishing a service on dbus, and if it's not assigned to anything, the python interpreter discards it, and thus destroys it, which probably causes the dbus service to disappear. Bonkers.

client.py

#!/usr/bin/env python

import dbus

bus = dbus.SessionBus()
service_name = 'org.example.Ui'
ui = bus.get_object(service_name, '/')
iface = dbus.Interface(ui, dbus_interface=service_name)

iface.LaunchBrowser()

server.py

#!/usr/bin/env python

import gobject

import dbus
import dbus.service
import dbus.mainloop.glib

import logging

logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

class Ui(dbus.service.Object):
    def __init__(self, bus, path):
        # Set up any needed state (hopefully none)
        dbus.service.Object.__init__(self, bus, path)

    @dbus.service.method("org.example.Ui",
                         in_signature='', out_signature='')
    def LaunchBrowser(self):
        logger.info("launchin' the browser")


if __name__ == '__main__':
    dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)

    loop = gobject.MainLoop()

    bus = dbus.SessionBus()

    bus_name = dbus.service.BusName('org.example.Ui', bus)
    Ui(bus, '/')

    loop.run()