dora does not handle concurrent call in python

[haixuanTao]

Discussed in https://github.com/orgs/dora-rs/discussions/746

^{Originally posted by jrabary January 6, 2025}
Hi all,

I'm trying to add an interactive and realtime visualisation node in my graph. I end up having the following events handlers in the GUI

    def handle_submit(command):
        if command != "":
            instruction_array = pa.array([command])
            node.send_output("instruction", instruction_array)
        return ""

    def handle_camera_streams():
        current_im = im
        while True:
            evt = node.next(timeout=FPS)
            if evt is not None:
                if evt["type"] == "INPUT":
                    if evt["id"] == "observations":
                        obs = decode_dict(evt["value"])
                        current_im = obs["overhead_cam"]

            yield current_im

The first one is to handle user action on the GUI and the second on to display a video stream on the GUI. The point is, the two handlers can work separatly but once I put them together I got some errors

node.send_output("instruction", instruction_array)
RuntimeError: Already borrowed

I suspect dora doesn't like I use the same node object concurrently.

Any ideas ?