Is there a way to share a variable between Python and JavaScript?

[schoenid]

I've got a custom node, which will update itself by writing to a widget.
It works fine on single execution, but in batch mode it fails.

I can change the function to not read the original value from the widget, count the iterations and update the widget value.
This works fine.
But if I read back the changed widget value, it fails every second time.
The update trough a onExecuted widget value overwrite is not reliable, because in batch mode the widgets value will be reset to earlier values trough system processes which I don't know

The problem is, if I change the widgets value manually, it won't be read.
So I need a variable to transfer the information, that the widget value has been changed by interaction trough an onNodeCreated callback.

Is there an easy way, to pass a variable, even it's just a boolean?
(I didn't find any or any documentation, how to do it ...)

The only way I found until now, is to add an additional widget, which can be used, but this looks not nice, because it can't be hidden.

[schoenid]

I found an option to hide a helper widget with the use of the "advanced": True, setting in INPUT_TYPES.
So I can use this as a workaround, to signal the Python half of the node to read the other widgets value.
Then I can set it back in the next iteration.

[schoenid]

Works great now!

[schoenid]

I found one BIG problem:

The async execution !

The JavaScipt portion of the node can be much slower, than the Python side.
In some situations, say in a batch mode with 4 executions, the pyton part can be finished, while the JavaScript part is on the first one.

I've stopped as example, the JavaScript execution in DevTools on the browser, then the Python part was executing all 4 steps, but without the modifications trough the JavaScript extension.
So it failed !!!

The JavaScript then executed the 4 iterations later and failed too.

Remark: I had the Python Debugger open the same time in VSC.

Is there a way to execute in sync ?

[schoenid]

My solution at the end is to do some self.control ;) means, controlling all the changements for a batch on the Python side and just updating the JavaScript values. Then after the batch has finished its run, the values will be correctly updated from the JavaScript side.