Improve and extend error handling on D-Bus connect (#5245)

* Improve and extend error handling on D-Bus connect

Avoid initializing the Supervisor board since it does not support the
Properties interface (see https://github.com/home-assistant/os-agent/issues/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

* Fix tests

* Use local variable

* Avoid stack trace when board support fails to load

* Fix tests

* Use override mechanism to disable Properties support

Instead of disable loading of Supervised entirly override initialization
to prevent loading the Properties interface.

* Revert "Fix tests"

This reverts commit 1e3c491ace.

supervisor/dbus/agent/__init__.py

@@ -8,7 +8,7 @@ from typing import Any
 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 +96,25 @@ class OSAgent(DBusInterfaceProxy):
         _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:
+                dbus = self.all[errors.index(err)]
+                _LOGGER.error(
+                    "Can't load OS Agent dbus interface %s %s: %s",
+                    dbus.bus_name,
+                    dbus.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 @@ import logging
 
 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,
@@ -75,6 +75,10 @@ class BoardManager(DBusInterfaceProxy):
             self._board_proxy = Green()
         elif self.board == BOARD_NAME_SUPERVISED:
             self._board_proxy = Supervised()
+        else:
+            return
 
-        if self._board_proxy:
+        try:
             await self._board_proxy.connect(bus)
+        except (DBusServiceUnkownError, DBusInterfaceError) as ex:
+            _LOGGER.warning("OS-Agent board support initialization failed: %s", ex)

supervisor/dbus/agent/boards/supervised.py

@@ -1,5 +1,9 @@
 """Supervised board management."""
 
+from typing import Any
+
+from supervisor.dbus.utils import dbus_connected
+
 from .const import BOARD_NAME_SUPERVISED
 from .interface import BoardProxy
 
@@ -11,3 +15,11 @@ class Supervised(BoardProxy):
         """Initialize properties."""
         super().__init__(BOARD_NAME_SUPERVISED)
         self.sync_properties: bool = False
+
+    @dbus_connected
+    async def update(self, changed: dict[str, Any] | None = None) -> None:
+        """Do nothing as there are no properties.
+
+        Currently unused, avoid using the Properties interface to avoid a bug in
+        Go D-Bus, see: https://github.com/home-assistant/os-agent/issues/206
+        """

supervisor/dbus/manager.py

@@ -129,9 +129,11 @@ class DBusManager(CoreSysAttributes):
 
         for err in errors:
             if err:
+                dbus = self.all[errors.index(err)]
                 _LOGGER.warning(
-                    "Can't load dbus interface %s: %s",
-                    self.all[errors.index(err)].name,
+                    "Can't load dbus interface %s %s: %s",
+                    dbus.name,
+                    dbus.object_path,
                     err,
                 )
 

supervisor/utils/dbus.py

@@ -112,6 +112,13 @@ class 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)

tests/dbus/agent/test_agent.py

@@ -44,15 +44,24 @@ async def test_dbus_osagent(
 
 
 @pytest.mark.parametrize(
-    "skip_service",
+    "skip_service,error",
     [
-        "os_agent",
-        "agent_apparmor",
-        "agent_datadisk",
+        ("os_agent", "No OS-Agent support on the host"),
+        (
+            "agent_apparmor",
+            "Can't load OS Agent dbus interface io.hass.os /io/hass/os/AppArmor",
+        ),
+        (
+            "agent_datadisk",
+            "Can't load OS Agent dbus interface io.hass.os /io/hass/os/DataDisk",
+        ),
     ],
 )
 async def test_dbus_osagent_connect_error(
-    skip_service: str, dbus_session_bus: MessageBus, caplog: pytest.LogCaptureFixture
+    skip_service: str,
+    error: str,
+    dbus_session_bus: MessageBus,
+    caplog: pytest.LogCaptureFixture,
 ):
     """Test OS Agent errors during connect."""
     os_agent_services = {
@@ -73,4 +82,4 @@ async def test_dbus_osagent_connect_error(
     os_agent = OSAgent()
     await os_agent.connect(dbus_session_bus)
 
-    assert "No OS-Agent support on the host" in caplog.text
+    assert error in caplog.text