Improve and extend error handling on D-Bus connect

Avoid initializing the Supervisor board since it does not support the
Properties interface (see home-assistant/os-agent#206).

This prevents the following somewhat confusing warning:
  No OS-Agent support on the host. Some Host functions have been disabled.

The OS Agent is actually installed on the host, it is just a single
object which caused issues. No functionalty was actually lost, as the
Supervisor board object has no features currently, and all other
interfaces got properly initialized still (thanks to gather()).

Print warnings more fine graned so it is clear which object exactly
causes an issue. Also print a log message on the lowest layer when an
error occures on calling D-Bus. This allows to easier track the actual
D-Bus error source.

Fixes: #5241

supervisor/dbus/agent/__init__.py

@@ -8,7 +8,7 @@
 from awesomeversion import AwesomeVersion
 from dbus_fast.aio.message_bus import MessageBus
 
-from ...exceptions import DBusError, DBusInterfaceError, DBusServiceUnkownError
+from ...exceptions import DBusInterfaceError, DBusServiceUnkownError
 from ..const import (
     DBUS_ATTR_DIAGNOSTICS,
     DBUS_ATTR_VERSION,
@@ -96,13 +96,24 @@ async def connect(self, bus: MessageBus) -> None:
         _LOGGER.info("Load dbus interface %s", self.name)
         try:
             await super().connect(bus)
-            await asyncio.gather(*[dbus.connect(bus) for dbus in self.all])
-        except DBusError:
-            _LOGGER.warning("Can't connect to OS-Agent")
         except (DBusServiceUnkownError, DBusInterfaceError):
-            _LOGGER.warning(
+            _LOGGER.error(
                 "No OS-Agent support on the host. Some Host functions have been disabled."
             )
+            return
+
+        errors = await asyncio.gather(
+            *[dbus.connect(bus) for dbus in self.all], return_exceptions=True
+        )
+
+        for err in errors:
+            if err:
+                _LOGGER.error(
+                    "Can't load OS Agent dbus interface %s %s: %s",
+                    self.all[errors.index(err)].bus_name,
+                    self.all[errors.index(err)].object_path,
+                    err,
+                )
 
     @dbus_connected
     async def update(self, changed: dict[str, Any] | None = None) -> None:

supervisor/dbus/agent/boards/__init__.py

@@ -4,7 +4,7 @@
 
 from dbus_fast.aio.message_bus import MessageBus
 
-from ....exceptions import BoardInvalidError
+from ....exceptions import BoardInvalidError, DBusInterfaceError, DBusServiceUnkownError
 from ...const import (
     DBUS_ATTR_BOARD,
     DBUS_IFACE_HAOS_BOARDS,
@@ -73,8 +73,16 @@ async def connect(self, bus: MessageBus) -> None:
             self._board_proxy = Yellow()
         elif self.board == BOARD_NAME_GREEN:
             self._board_proxy = Green()
-        elif self.board == BOARD_NAME_SUPERVISED:
-            self._board_proxy = Supervised()
-
-        if self._board_proxy:
+        # Currently unused, avoid initialization due to a bug in introspection:
+        # See: https://github.com/home-assistant/os-agent/issues/206
+        # elif self.board == BOARD_NAME_SUPERVISED:
+        #     self._board_proxy = Supervised()
+        else:
+            return
+
+        try:
             await self._board_proxy.connect(bus)
+        except (DBusServiceUnkownError, DBusInterfaceError) as ex:
+            _LOGGER.warning(
+                "OS-Agent Board support initialization failed.", exc_info=ex
+            )

supervisor/dbus/manager.py

@@ -130,8 +130,9 @@ async def load(self) -> None:
         for err in errors:
             if err:
                 _LOGGER.warning(
-                    "Can't load dbus interface %s: %s",
+                    "Can't load dbus interface %s %s: %s",
                     self.all[errors.index(err)].name,
+                    self.all[errors.index(err)].object_path,
                     err,
                 )
 

supervisor/utils/dbus.py

@@ -112,6 +112,13 @@ async def call_dbus(
                 )
             return await getattr(proxy_interface, method)(*args)
         except DBusFastDBusError as err:
+            _LOGGER.debug(
+                "D-Bus fast error on call - %s.%s on %s: %s",
+                proxy_interface.introspection.name,
+                method,
+                proxy_interface.path,
+                err,
+            )
             raise DBus.from_dbus_error(err) from None
         except Exception as err:  # pylint: disable=broad-except
             capture_exception(err)