Bug#996911: systemd: dbus signal JobRemoved for a failed job is 'done' instead of 'failed'

[Alexandre Rossi]

Hi,

> > I usually recommend to use Type=notify or if that is not possible, I
> > think forking is better then simple for most cases.
> 
> See the difference:
> 
> # systemctl cat fail.service
> # /etc/systemd/system/fail.service
> [Unit]
> Description=fail
> 
> [Service]
> Type=simple
> ExecStart=/bin/false
> 
> # systemctl start fail.service
> 
> # echo $?
> 0

Thank you very much for the explaination. I know understand my confusion
between the Job result and Unit states.

My test program becomes:

--
#!/usr/bin/python3

from gi.repository import GLib

import dbus
import dbus.mainloop.glib


def subscribe():
    sysbus = dbus.SystemBus()
    systemd1 = sysbus.get_object('org.freedesktop.systemd1',
                                 '/org/freedesktop/systemd1')

    def get_unit_state(unit_name):
        unit = manager.GetUnit(unit_name)
        unit_if = sysbus.get_object('org.freedesktop.systemd1', unit)
        unit_props = dbus.Interface(unit_if, 'org.freedesktop.DBus.Properties')
        print('Unit %s: ActiveState=%s, SubState=%s'
              % (unit,
                 unit_props.Get('org.freedesktop.systemd1.Unit', 'ActiveState'),
                 unit_props.Get('org.freedesktop.systemd1.Unit', 'SubState')))

    def systemd_event_cb(pid, jobid, unit, result):
        print('received event for unit %s with result %s'
            % (unit, result))
        get_unit_state(unit)
        print('and some time later')
        GLib.timeout_add(1000, get_unit_state, unit)

    systemd1.connect_to_signal('JobRemoved', systemd_event_cb)
    manager = dbus.Interface(systemd1,
                             'org.freedesktop.systemd1.Manager')
    manager.Subscribe()

GLib.timeout_add(100, subscribe)

dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)
loop = GLib.MainLoop()

loop.run()
--

Now the output is:
--
received event for unit fail.service with result done
Unit /org/freedesktop/systemd1/unit/fail_2eservice: ActiveState=failed, SubState=failed
and some time later
Unit /org/freedesktop/systemd1/unit/fail_2eservice: ActiveState=failed, SubState=failed
received event for unit davmail.service with result done
Unit /org/freedesktop/systemd1/unit/davmail_2eservice: ActiveState=active, SubState=running
and some time later
Unit /org/freedesktop/systemd1/unit/davmail_2eservice: ActiveState=failed, SubState=failed
--

I can use Unit ActiveState to assess Unit failure but need to wait a bit for
some services as the failed state is not immediate.

Also I'll try to fix davmail following your advice.

Thanks,

Alex