How to Monitor Cron Jobs with ntfy.sh

In an earlier blogpost i lined out how i was working with cronjobs. The thing is everything works fine until it does not. And you want to know when it does not work fine anymore. And this is the reason why you monitor your cronjobs. So i was looking after the best and easiest way to do this: There does not even need to be a discussion to be about this. By far the best and easiest solution to get notified if your cronjob fails is ntfy.sh.

ntfy.sh lets you send push notifications to your browser (or phone if you install the app) via HTTP PUT or POST request. This is how you set it up:

1. Go to ntfy.sh and make an account

2. In the sidebar click 'Subscribe to topic'

3. Give your topic any name (better make it non-recognizable since it is publicly visible), e.g. 'scraper_failed_328' and subscribe. You can test the notification manually:

   curl -d "Test: Scraper failed at $(date)" ntfy.sh/scraper_failed_328
   

4. Use the topic name together with the ntfy.sh domain to send a POST request to your topic. For my nextgenenergyjobs.com scraper this looks e.g. like this (the double pipe operator gets triggered when the previous command fails (non-zero exit status)):

   0 9 * * * /bin/bash -c 'cd /home/scraperuser/projects/best-jobscraper-in-the-world && source .venv/bin/activate && python3 src/main.py' >> /home/scraperuser/jobscraper.log 2>&1 || curl -d "Scraper failed at $(date)" ntfy.sh/scraper_failed_328'
   

And this is it!

Do you have experience with other monitoring solutions for cronjobs? I'd love to hear about your approach - feel free to reach out!