spiegel-keyman/linux/keyman-config/keyman_config/dbus_util.py
Eberhard Beilharz 7da6a4e98c
Apply suggestions from code review
Co-authored-by: Marc Durdin <marc@durdin.net>
2025-10-16 15:17:35 +02:00

107 lines
4 KiB
Python

#!/usr/bin/python3
import contextlib
import logging
import os
import subprocess
import dbus
import dbus.bus
import dbus.mainloop.glib
import dbus.service
from dbus import DBusException
BUS_NAME = 'com.Keyman.Config'
OBJECT_PATH = '/com/Keyman/Config'
DBusSessionBusAddressValue = f'unix:path=/run/user/{os.environ.get("SUDO_UID")}/bus'
DBusSessionBusAddress = f'DBUS_SESSION_BUS_ADDRESS={DBusSessionBusAddressValue}'
XdgRuntimeDir = f'XDG_RUNTIME_DIR=/run/user/{os.environ.get("SUDO_UID")}'
__keyman_config_service = None
class KeymanConfigService(dbus.service.Object):
def __init__(self, bus, handler) -> None:
self.__keyboard_list_changed_handler = handler
self.__bus = bus
bus_name = dbus.service.BusName(BUS_NAME, bus=self.__bus, do_not_queue=True)
dbus.service.Object.__init__(self, bus_name, OBJECT_PATH)
@dbus.service.signal(BUS_NAME)
def KeyboardListChangedSignal(self):
pass
@dbus.service.method(BUS_NAME)
def keyboard_list_changed(self):
logging.debug(f"{os.getpid()}: -------------keyboard_list_changed--------------------")
if self.__keyboard_list_changed_handler:
self.__keyboard_list_changed_handler()
self.KeyboardListChangedSignal()
def keyboard_list_changed():
if os.environ.get('SUDO_USER'):
args = ['sudo', '-u', os.environ.get('SUDO_USER'), 'dbus-send',
f'--bus={DBusSessionBusAddressValue}',
'/com/Keyman/Config', 'com.Keyman.Config.keyboard_list_changed']
subprocess.run(args)
else:
get_keyman_config_service().keyboard_list_changed()
class KeymanConfigServiceManager:
def __init__(self, handler):
self.__name_owner_watch = None
self.__signal_receiver = None
self.__service = None
self.__keyboard_list_changed_handler = handler
loop = dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)
self.__bus = dbus.SessionBus(loop)
self.__name_owner_watch = self.__bus.watch_name_owner(BUS_NAME, self.__name_owner_changed)
def __is_name_owner(self) -> bool:
retval = self.__bus.request_name(BUS_NAME, dbus.bus.NAME_FLAG_DO_NOT_QUEUE)
return retval in [
dbus.bus.REQUEST_NAME_REPLY_ALREADY_OWNER,
dbus.bus.REQUEST_NAME_REPLY_PRIMARY_OWNER,
]
def __create_service(self) -> None:
if self.__signal_receiver:
self.__signal_receiver.remove()
self.__signal_receiver = None
if self.__is_name_owner():
logging.debug(f'{os.getpid()}: I am now owner ({self.__bus.get_name_owner(BUS_NAME)})')
if self.__name_owner_watch:
self.__name_owner_watch.cancel()
self.__name_owner_watch = None
self.__service = KeymanConfigService(self.__bus, self.__keyboard_list_changed_handler)
else:
logging.debug(f'{os.getpid()}: Not owner. Owner is {self.__bus.get_name_owner(BUS_NAME)}. Connecting signal')
self.__service = self.__bus.get_object(BUS_NAME, OBJECT_PATH, introspect=False)
if self.__keyboard_list_changed_handler:
self.__signal_receiver = self.__service.connect_to_signal(
'KeyboardListChangedSignal', self.__keyboard_list_changed_handler, dbus_interface=BUS_NAME)
def __name_owner_changed(self, new_owner) -> None:
logging.debug(f'{os.getpid()}: Owner changed. Recreating service.')
self.__create_service()
def __verify_service_exists(self) -> None:
if not self.__service:
self.__create_service()
def keyboard_list_changed(self) -> None:
self.__verify_service_exists()
if not self.__service:
return
with contextlib.suppress(DBusException):
self.__service.keyboard_list_changed()
def get_keyman_config_service(handler=None) -> KeymanConfigServiceManager:
global __keyman_config_service
if not __keyman_config_service:
__keyman_config_service = KeymanConfigServiceManager(handler)
return __keyman_config_service