Still can't request message details of common messages

[scottbell]

Description
Per #688, when trying to use the RosAPI to request message details I get an exception in the rosapi node. This happens with a common messages included with ROS2.

• Library Version: 1.3.1-1jammy.20221207.042258
• ROS Version: humble
• Platform / OS: Ubuntu 22.04.1

Steps To Reproduce

ros2 service call /rosapi/message_details rosapi_msgs/srv/MessageDetails "{type: std_msgs/Float32}"

Expected Behavior
Return message details for the requested message type.

Actual Behavior

$ ros2 launch rosbridge_server rosbridge_websocket_launch.xml 
[INFO] [launch]: All log files can be found below /home/scott/.ros/log/2023-01-06-12-05-52-599792-rosmachine-4566
[INFO] [launch]: Default logging verbosity is set to INFO
[INFO] [rosbridge_websocket-1]: process started with pid [4567]
[INFO] [rosapi_node-2]: process started with pid [4569]
[rosbridge_websocket-1] [INFO] [1673003153.749749059] [rosbridge_websocket]: Rosbridge WebSocket server started on port 9090
[rosapi_node-2] Traceback (most recent call last):
[rosapi_node-2]   File "/opt/ros/humble/lib/rosapi/rosapi_node", line 329, in <module>
[rosapi_node-2]     main()
[rosapi_node-2]   File "/opt/ros/humble/lib/rosapi/rosapi_node", line 321, in main
[rosapi_node-2]     rclpy.spin(node)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/__init__.py", line 222, in spin
[rosapi_node-2]     executor.spin_once()
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py", line 713, in spin_once
[rosapi_node-2]     raise handler.exception()
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/task.py", line 239, in __call__
[rosapi_node-2]     self._handler.send(None)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py", line 418, in handler
[rosapi_node-2]     await call_coroutine(entity, arg)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py", line 372, in _execute_service
[rosapi_node-2]     response = await await_or_execute(srv.callback, request, srv.srv_type.Response())
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py", line 107, in await_or_execute
[rosapi_node-2]     return callback(*args)
[rosapi_node-2]   File "/opt/ros/humble/lib/rosapi/rosapi_node", line 228, in get_message_details
[rosapi_node-2]     dict_to_typedef(d) for d in objectutils.get_typedef_recursive(request.type)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 98, in get_typedef_recursive
[rosapi_node-2]     return _get_typedefs_recursive(type, [])
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 223, in _get_typedefs_recursive
[rosapi_node-2]     typedef = get_typedef(type)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 78, in get_typedef
[rosapi_node-2]     return _get_typedef(instance)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 164, in _get_typedef
[rosapi_node-2]     fieldtypes.append(_type_name(field_type, field_instance))
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 253, in _type_name
[rosapi_node-2]     return _type_name_from_instance(instance)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 257, in _type_name_from_instance
[rosapi_node-2]     mod = instance.__module__
[rosapi_node-2] AttributeError: 'float' object has no attribute '__module__'. Did you mean: '__mod__'?
[ERROR] [rosapi_node-2]: process has died [pid 4569, exit code 1, cmd '/opt/ros/humble/lib/rosapi/rosapi_node --ros-args -r __node:=rosapi --params-file /tmp/launch_params_2df8zmzu --params-file /tmp/launch_params_m6j5dj79 --params-file /tmp/launch_params_tg0uwis_'].

Using @GiteZz's fix, I was able to get a bit further, but now crashing asking about rcl_interfaces/msg/ParameterEvent}. E.g.,:
ros2 service call /rosapi/message_details rosapi_msgs/srv/MessageDetails "{type: rcl_interfaces/msg/ParameterEvent}"
causes:

$ ros2 launch rosbridge_server rosbridge_websocket_launch.xml 
[INFO] [launch]: All log files can be found below /home/scott/.ros/log/2023-01-06-12-11-30-370701-rosmachine-4691
[INFO] [launch]: Default logging verbosity is set to INFO
[INFO] [rosbridge_websocket-1]: process started with pid [4692]
[INFO] [rosapi_node-2]: process started with pid [4694]
[rosbridge_websocket-1] [INFO] [1673003491.543589196] [rosbridge_websocket]: Rosbridge WebSocket server started on port 9090
[rosapi_node-2] Traceback (most recent call last):
[rosapi_node-2]   File "/opt/ros/humble/lib/rosapi/rosapi_node", line 329, in <module>
[rosapi_node-2]     main()
[rosapi_node-2]   File "/opt/ros/humble/lib/rosapi/rosapi_node", line 321, in main
[rosapi_node-2]     rclpy.spin(node)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/__init__.py", line 222, in spin
[rosapi_node-2]     executor.spin_once()
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py", line 713, in spin_once
[rosapi_node-2]     raise handler.exception()
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/task.py", line 239, in __call__
[rosapi_node-2]     self._handler.send(None)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py", line 418, in handler
[rosapi_node-2]     await call_coroutine(entity, arg)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py", line 372, in _execute_service
[rosapi_node-2]     response = await await_or_execute(srv.callback, request, srv.srv_type.Response())
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py", line 107, in await_or_execute
[rosapi_node-2]     return callback(*args)
[rosapi_node-2]   File "/opt/ros/humble/lib/rosapi/rosapi_node", line 228, in get_message_details
[rosapi_node-2]     dict_to_typedef(d) for d in objectutils.get_typedef_recursive(request.type)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 97, in get_typedef_recursive
[rosapi_node-2]     return _get_typedefs_recursive(type, [])
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 227, in _get_typedefs_recursive
[rosapi_node-2]     return _get_subtypedefs_recursive(typedef, typesseen)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 237, in _get_subtypedefs_recursive
[rosapi_node-2]     typedefs = typedefs + _get_typedefs_recursive(fieldtype, typesseen)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 227, in _get_typedefs_recursive
[rosapi_node-2]     return _get_subtypedefs_recursive(typedef, typesseen)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 237, in _get_subtypedefs_recursive
[rosapi_node-2]     typedefs = typedefs + _get_typedefs_recursive(fieldtype, typesseen)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 227, in _get_typedefs_recursive
[rosapi_node-2]     return _get_subtypedefs_recursive(typedef, typesseen)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 237, in _get_subtypedefs_recursive
[rosapi_node-2]     typedefs = typedefs + _get_typedefs_recursive(fieldtype, typesseen)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 225, in _get_typedefs_recursive
[rosapi_node-2]     typedef = get_typedef(type)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 76, in get_typedef
[rosapi_node-2]     instance = ros_loader.get_message_instance(type)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosbridge_library/internal/ros_loader.py", line 91, in get_message_instance
[rosapi_node-2]     cls = get_message_class(typestring)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosbridge_library/internal/ros_loader.py", line 78, in get_message_class
[rosapi_node-2]     return _get_msg_class(typestring)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosbridge_library/internal/ros_loader.py", line 122, in _get_msg_class
[rosapi_node-2]     return _get_class(typestring, subname, _loaded_msgs, _msgs_lock)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosbridge_library/internal/ros_loader.py", line 163, in _get_class
[rosapi_node-2]     modname, classname = _splittype(typestring)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosbridge_library/internal/ros_loader.py", line 213, in _splittype
[rosapi_node-2]     raise InvalidTypeStringException(typestring)
[rosapi_node-2] rosbridge_library.internal.ros_loader.InvalidTypeStringException: octet is not a valid type string
[ERROR] [rosapi_node-2]: process has died [pid 4694, exit code 1, cmd '/opt/ros/humble/lib/rosapi/rosapi_node --ros-args -r __node:=rosapi --params-file /tmp/launch_params_eoskae9r --params-file /tmp/launch_params_oehzpv9e --params-file /tmp/launch_params_nq64wis7'].

[brag00n]

Hello, I have got the same issue using roslibpy API call. E.g.:
roslibpy.Ros.get_message_details('geometry_msgs/msg/PoseWithCovarianceStamped')
cause:

[rosapi_node-2] Traceback (most recent call last):
[rosapi_node-2]   File "/opt/ros/humble/lib/rosapi/rosapi_node", line 329, in <module>
[rosapi_node-2]     main()
[rosapi_node-2]   File "/opt/ros/humble/lib/rosapi/rosapi_node", line 321, in main
[rosapi_node-2]     rclpy.spin(node)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/__init__.py", line 222, in spin
[rosapi_node-2]     executor.spin_once()
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py", line 713, in spin_once
[rosapi_node-2]     raise handler.exception()
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/task.py", line 239, in __call__
[rosapi_node-2]     self._handler.send(None)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py", line 418, in handler
[rosapi_node-2]     await call_coroutine(entity, arg)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py", line 372, in _execute_service
[rosapi_node-2]     response = await await_or_execute(srv.callback, request, srv.srv_type.Response())
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py", line 107, in await_or_execute
[rosapi_node-2]     return callback(*args)
[rosapi_node-2]   File "/opt/ros/humble/lib/rosapi/rosapi_node", line 228, in get_message_details
[rosapi_node-2]     dict_to_typedef(d) for d in objectutils.get_typedef_recursive(request.type)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 98, in get_typedef_recursive
[rosapi_node-2]     return _get_typedefs_recursive(type, [])
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 225, in _get_typedefs_recursive
[rosapi_node-2]     return _get_subtypedefs_recursive(typedef, typesseen)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 235, in _get_subtypedefs_recursive
[rosapi_node-2]     typedefs = typedefs + _get_typedefs_recursive(fieldtype, typesseen)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 223, in _get_typedefs_recursive
[rosapi_node-2]     typedef = get_typedef(type)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 78, in get_typedef
[rosapi_node-2]     return _get_typedef(instance)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 164, in _get_typedef
[rosapi_node-2]     fieldtypes.append(_type_name(field_type, field_instance))
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 253, in _type_name
[rosapi_node-2]     return _type_name_from_instance(instance)
[rosapi_node-2]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py", line 257, in _type_name_from_instance
[rosapi_node-2]     mod = instance.__module__
[rosapi_node-2] AttributeError: 'numpy.ndarray' object has no attribute '__module__'. Did you mean: '__mod__'?

[scottbell]

@brag00n that specific error can be fixed by changing /opt/ros/humble/local/lib/python3.10/dist-packages/rosapi/objectutils.py, specifically:
the atomics array needs the float type so it doesn't try to call __module__ on it in the _type_name function. See @GiteZz's response for the full list of atomic types that should be added.

[scottbell]

Note I've got a fork here:
ros2...scottbell:rosbridge_suite:ros2

that addresses the crashing. Namely, if we can't lookup a type, output an error and return None back to the client. The main issue (after adding the extra native type per @GiteZz) seems to be coming here where the code assumes the type string will be of a certain form. If the type is a sequence, the string parsing logic here fails.