How to Get Notifications When Exceptions Occur in Jupyter Notebook

Have you ever been running a time-consuming code in Jupyter Notebook, like training a machine learning model, only to realize later that it had stopped due to an unexpected error?

In this article, I’ll introduce a method to automatically send notifications to platforms like Slack or Discord when such exceptions occur.

Creating a Notification Function

First, let’s prepare a function for sending notifications. If you’re using Slack or Discord, you can notify with the following functions:

• Script for Slack Notification:

  import requests
  
  def slack_notify(message, webhook_url):
      """Notify Slack."""
      requests.post(webhook_url, json={"text": message})
  

• Script for Discord Notification:

  import requests
  
  def discord_notify(message, webhook_url):
      """Notify Discord."""
      requests.post(webhook_url, json={"content": message})
  

Execute Script in Jupyter Notebook When an Exception Occurs

By using the set_custom_exc function, you can add additional processes during exceptions.
The code below is mostly based on this answer from stackoverflow.

from IPython import get_ipython
from IPython.core.ultratb import AutoFormattedTB

def jupyter_preprocess():
    """Function to run at the start of Jupyter Notebook."""
    # ref. https://stackoverflow.com/a/40135960
    itb = AutoFormattedTB(mode='Plain', tb_offset=1)
    def custom_exc(shell, etype, evalue, tb, tb_offset=None):
        shell.showtraceback((etype, evalue, tb), tb_offset=tb_offset)
        stb = itb.structured_traceback(etype, evalue, tb)
        sstb = itb.stb2text(stb)

        # Write the code to be executed during an exception here
        slack_notify("ERROR: An exception has occurred.", "<WEBHOOK URL>")

        return sstb

    get_ipython().set_custom_exc((Exception,), custom_exc)

By running the above jupyter_preprocess function at the start, you’ll receive notifications when exceptions occur. As the code shows, you can also implement other processes besides notifications, like server shutdowns, and so on.