stop notebook on error about gophernotes HOT 2 OPEN

You want to stop a notebook server programmatically?

Executing os.Exit will cause gophernotes to exit, but jupyter (or whatever notebook frontend you are using) will just notice it,
show a message similar to

Kernel Restarting
The kernel appears to have died. It will restart automatically.

and start another gophernotes process.

So the solution, if any, is to send a ZMQ message from gophernotes to the notebook asking it to exit.
Spoiler: I have no idea if notebook's protocol define such a message. Maybe @sbinet ?

from gophernotes.

seems possible at the protocol level:

• https://jupyter-client.readthedocs.io/en/latest/messaging.html#messages-on-the-control-router-dealer-channel
• https://jupyter-client.readthedocs.io/en/latest/messaging.html#kernel-interrupt

from gophernotes.