Add filter to dbus signal handle

Custom user handlers receive all messages sent to the service so we need
to filter out unwanted messages. dbus-next messages have a built-in
`_matches` method so we can use this.

libqtile/utils.py

@@ -508,14 +508,14 @@ async def add_signal_receiver(
             return False
 
     match_args = {
-        "type": "signal",
         "sender": bus_name,
         "member": signal_name,
         "path": path,
         "interface": dbus_interface,
     }
 
-    rule = ",".join("{}='{}'".format(k, v) for k, v in match_args.items() if v)
+    rule = "type='signal',"
+    rule += ",".join("{}='{}'".format(k, v) for k, v in match_args.items() if v)
 
     logger.debug("Adding dbus match rule: %s", rule)
 
@@ -532,7 +532,15 @@ async def add_signal_receiver(
 
     # Check if message sent successfully
     if bus and msg and msg.message_type == MessageType.METHOD_RETURN:
-        bus.add_message_handler(callback)
+
+        def signal_callback_wrapper(msg: Message) -> None:
+            """Custom wrapper to only run callback if message matches our rule."""
+            if msg.message_type == MessageType.SIGNAL and msg._matches(
+                **{k: v for k, v in match_args.items() if v}
+            ):
+                callback(msg)
+
+        bus.add_message_handler(signal_callback_wrapper)
         return True
 
     else:

libqtile/widget/keyboardkbdd.py

@@ -22,8 +22,6 @@
 
 import re
 
-from dbus_next.constants import MessageType
-
 from libqtile.log_utils import logger
 from libqtile.utils import add_signal_receiver
 from libqtile.widget import base
@@ -90,9 +88,6 @@ async def _config_async(self):
             logger.warning("Could not subscribe to kbdd signal.")
 
     def _signal_received(self, message):
-        if message.message_type != MessageType.SIGNAL:
-            return
-
         self._layout_changed(*message.body)
 
     def _layout_changed(self, layout_changed):

libqtile/widget/mpris2widget.py

@@ -252,9 +252,6 @@ def _name_owner_changed(self, message):
             self._set_background_poll(False)
 
     def message(self, message):
-        if message.message_type != MessageType.SIGNAL:
-            return
-
         create_task(self.process_message(message))
 
     async def process_message(self, message):

test/widgets/docs_screenshots/ss_keyboardkbdd.py

@@ -17,21 +17,18 @@
 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
-import sys
 from importlib import reload
 
 import pytest
 
-from test.widgets.test_keyboardkbdd import Mockconstants, MockSpawn, mock_signal_receiver
+from test.widgets.test_keyboardkbdd import MockSpawn, mock_signal_receiver
 
 
 @pytest.fixture
 def widget(monkeypatch):
-    monkeypatch.setitem(sys.modules, "dbus_next.constants", Mockconstants("dbus_next.constants"))
     from libqtile.widget import keyboardkbdd
 
     reload(keyboardkbdd)
-    monkeypatch.setattr("libqtile.widget.keyboardkbdd.MessageType", Mockconstants.MessageType)
     monkeypatch.setattr(
         "libqtile.widget.keyboardkbdd.KeyboardKbdd.call_process", MockSpawn.call_process
     )

test/widgets/test_keyboardkbdd.py

@@ -25,9 +25,7 @@
 
 # This test file covers the remaining widget code
 
-import sys
 from importlib import reload
-from types import ModuleType
 
 import pytest
 
@@ -38,11 +36,6 @@ async def mock_signal_receiver(*args, **kwargs):
     return True
 
 
-class Mockconstants(ModuleType):
-    class MessageType:
-        SIGNAL = 1
-
-
 class MockSpawn:
     call_count = 0
 
@@ -62,13 +55,11 @@ def __init__(self, is_signal=True, body=0):
 
 @pytest.fixture
 def patched_widget(monkeypatch):
-    monkeypatch.setitem(sys.modules, "dbus_next.constants", Mockconstants("dbus_next.constants"))
     from libqtile.widget import keyboardkbdd
 
     reload(keyboardkbdd)
 
     # The next line shouldn't be necessary but I got occasional failures without it when testing locally
-    monkeypatch.setattr("libqtile.widget.keyboardkbdd.MessageType", Mockconstants.MessageType)
     monkeypatch.setattr(
         "libqtile.widget.keyboardkbdd.KeyboardKbdd.call_process", MockSpawn.call_process
     )
@@ -89,11 +80,6 @@ def test_keyboardkbdd_process_running(fake_qtile, patched_widget, fake_window):
     kbd._signal_received(message)
     assert kbd.keyboard == "us"
 
-    # Test non-"signal" message
-    message = MockMessage(body=0, is_signal=False)
-    kbd._signal_received(message)
-    assert kbd.keyboard == "us"
-
 
 def test_keyboardkbdd_process_not_running(fake_qtile, patched_widget, fake_window):
     MockSpawn.call_count = 0