Unknown DBus data type on Flutter

[long1eu]

Hi!

I was trying to interface with the NetworkManger via dbus to provide linux implementation for the flutter connectivity plugin.
The source code can be found here.
https://github.com/fluttercommunity/firebase_dart_sdk/blob/1dc2373b9524b8a429d6bad32a127eb497fc7b0f/connectivity_linux/lib/connectivity_linux.dart#L81

Note: This only happens when I run the flutter app. When I run it as a simple dart app everything worked well.

Thank you.

Distributor ID:	Ubuntu
Description:	Ubuntu 18.04.5 LTS
Release:	18.04
Codename:	bionic

Launching lib/main.dart on Linux in debug mode...
Building Linux application...
Waiting for Linux to report its views...
Debug service listening on ws://127.0.0.1:46223/qySq3Oyb90M=/ws
Syncing files to device Linux...
[ERROR:flutter/lib/ui/ui_dart_state.cc(171)] Unhandled Exception: Unknown DBus data type '5fc6b82c95f466712
l����   �   =   ��s �   :1.297  ��u �  �g �s  ��s �   org.freedesktop.DBus    '
#0      DBusReadBuffer.readDBusValue (package:dbus/src/dbus_read_buffer.dart:253:7)
#1      DBusReadBuffer.readDBusVariant (package:dbus/src/dbus_read_buffer.dart:160:22)
#2      DBusReadBuffer.readDBusValue (package:dbus/src/dbus_read_buffer.dart:239:14)
#3      DBusReadBuffer.readDBusStruct (package:dbus/src/dbus_read_buffer.dart:169:19)
#4      DBusReadBuffer.readDBusValue (package:dbus/src/dbus_read_buffer.dart:251:14)
#5      DBusReadBuffer.readDBusArray (package:dbus/src/dbus_read_buffer.dart:184:19)
#6      DBusMessage.unmarshal (package:dbus/src/dbus_message.dart:125:26)
#7      DBusClient._processMessages (package:dbus/src/dbus_client.dart:488:18)
#8      DBusClient._processData (package:dbus/src/dbus_client.dart:463:20)
#9      _rootRunUnary (dart:async/zone.dart:1198:47)
#10     _CustomZone.runUnary (dart:async/zone.dart:1100:19)
#11     _CustomZone.runUnaryGuarded (dart:async/zone.dart:1005:7)
#12     _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:357:11)
#13     _BufferingStreamSubscription._add (dart:async/stream_impl.dart:285:7)
#14     _SyncStreamControllerDispatch._sendData (dart:async/stream_controller.dart:808:19)
#15     _StreamController._add (dart:async/stream_controller.dart:682:7)
#16     _StreamController.add (dart:async/stream_controller.dart:624:5)
#17     _Socket._onData (dart:io-patch/socket_patch.dart:2043:41)
#18     _rootRunUnary (dart:async/zone.dart:1206:13)
#19     _CustomZone.runUnary (dart:async/zone.dart:1100:19)
#20     _CustomZone.runUnaryGuarded (dart:async/zone.dart:1005:7)
#21     _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:357:11)
#22     _BufferingStreamSubscription._add (dart:async/stream_impl.dart:285:7)
#23     _SyncStreamControllerDispatch._sendData (dart:async/stream_controller.dart:808:19)
#24     _StreamController._add (dart:async/stream_controller.dart:682:7)
#25     _StreamController.add (dart:async/stream_controller.dart:624:5)
#26     new _RawSocket.<anonymous closure> (dart:io-patch/socket_patch.dart:1579:33)
#27     _NativeSocket.issueReadEvent.issue (dart:io-patch/socket_patch.dart:1075:14)
#28     _microtaskLoop (dart:async/schedule_microtask.dart:41:21)
#29     _startMicrotaskLoop (dart:async/schedule_microtask.dart:50:5)

[robert-ancell]

Thanks for reporting this! I've been seeing a similar issue when implementing #74 and also trying to contact NetworkManager.

[robert-ancell]

This should be fixed in 0.0.0-dev.16

[robert-ancell]

Actually I think this is multiple async calls occurring at once - the connect logic in DBusClient doesn't currently handle this correctly.

[long1eu]

offtopic: since there is a notification package, do you think it would better if we would have a network_manager package?

[robert-ancell]

Yes I do. I'm working my way towards making that.

[robert-ancell]

OK, now I think it's fixed in 0.0.0-dev.17, please re-open if not!