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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Async method calls do not show/print exceptions","articleBody":"If the exception occur in a method callback, the exception is not shown:\n\n```python\nimport asyncio\nimport sdbus\n\nclass Test(sdbus.DbusInterfaceCommonAsync, interface_name=\"org.test\"):\n    @sdbus.dbus_method_async(result_signature=\"u\")\n    async def open(self) -\u003e int:\n        print(\"Open call\")\n        raise ValueError(\"Nooo\")\n\ntest = Test()\n\nasync def startup() -\u003e None:\n    await sdbus.request_default_bus_name_async('org.example.test')\n    test.export_to_dbus(\"/\")\n\nloop = asyncio.new_event_loop()\nloop.run_until_complete(startup())\nloop.run_until_complete(asyncio.sleep(10))\nprint(\"Done\")\n```\n\n```console\n$ ./test.py\nOpen call\nDone\n```\n\n```console\n$ gdbus call --session --dest org.example.test --object-path / --method org.test.Open\nError: GDBus.Error:org.freedesktop.DBus.Error.Failed:\n```\n\nIt is visible on the client side that something was wrong `DBus.Error.Failed`, but it's hard to tell what was wrong. It would be nice to have a traceback printed in case of an exception in a D-Bus API handler (method or property). However, I'm not sure whether that is intentional or a bug?\n\nAs a workaround I can wrap method/property code in a try/except block, but I think that it would be nicer to have a traceback in case of non-DBus exception. If someone would like to return an error from a method/property, a dedicated DBus exception should be used. What do you think? Otherwise it's really, reaaaaalllyyy hard to debug issues (e.g. a simple typo) in a program based on sdbus library.\n\nIf not, the returned D-Bus error should at least have the `ValueError`'s message included.\n\n#### Setup\n\nsdbus was installed via PIP:\n\n```console\n$ pip freeze |grep sdbus\nsdbus==0.13.0\n```","author":{"url":"https://github.com/arkq","@type":"Person","name":"arkq"},"datePublished":"2025-03-06T10:10:33.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":4},"url":"https://github.com/97/python-sdbus/issues/97"}