#!/usr/bin/python3
#
# Copyright 2016 Canonical Ltd
#
# Author: Brad Marshall <brad.marshall@canonical.com>
#
# Based on check_upstart_job and https://zignar.net/2014/09/08/getting-started-with-dbus-python-systemd/
#

import dbus, sys

service_arg = sys.argv[1]
service_name = "%s.service" % service_arg

try:
    bus = dbus.SystemBus()
    systemd = bus.get_object('org.freedesktop.systemd1', '/org/freedesktop/systemd1')
    manager = dbus.Interface(systemd, dbus_interface='org.freedesktop.systemd1.Manager')
    try:
        service_unit = manager.LoadUnit(service_name)
        service_proxy = bus.get_object('org.freedesktop.systemd1', str(service_unit))
        service = dbus.Interface(service_proxy, dbus_interface='org.freedesktop.systemd1.Unit')
        service_res = service_proxy.Get('org.freedesktop.systemd1.Unit','SubState', dbus_interface='org.freedesktop.DBus.Properties')

        if service_res == 'running':
            print('OK: %s is running' % service_name)
            sys.exit(0)
        else:
            print('CRITICAL: %s is not running' % service_name)
            sys.exit(2)

    except dbus.DBusException as e:
        print('CRITICAL: unable to find %s in systemd' % service_name)
        sys.exit(2)

except dbus.DBusException as e:
    print('CRITICAL: unable to connect to system for %s' % service_name)
    sys.exit(2)