[rmarren1]

This solution uses the flask got_request_exception method to call a block of code before an exception is raised in the Dash backend when debug=True. In this block of code, we use socket.io (Flask-SocketIO) to emit an 'error' event from the namespace /{prefix}_dash-errors endpoint which includes error information like the Exception name, message, and traceback.

Still need to figure out:

• socket.io prints logs every couple of seconds which is annoying, can't figure out how to turn them off.
• does wrapping the server in a SocketIO instance in this line: socketio = SocketIO(self.server) break anything in servers which use Dash plus some other Flask plugins?

[rmarren1]

Closing in favor of catching exceptions in the front-end. In this solution, the error data transferred over to the front-end was the input to the flask exception handler rather than the output, so we did not get the nice werkzueg error pages.