DevOps Engineers Rejoice: Python Script Replaces $10k SSL Monitoring SaaS with 50 Lines of Code and a Slack Webhook

A recent guide published on TechResolve.blog provides a comprehensive solution to monitor SSL certificate expiry using Python and the Slack API. The automated system aims to prevent service outages and reputational damage caused by manual monitoring inefficiencies. By leveraging Python's ssl and socket modules, combined with pyopenssl, the script connects to domains, fetches raw DER-encoded X.509 certificates, and parses their notAfter expiry timestamps. The solution integrates with Slack Incoming Webhooks, sending timely alerts to specified channels when certificates are nearing expiry, based on a configurable threshold of 30 days. The script can be scheduled to run periodically using system schedulers like cron on Linux, ensuring continuous monitoring without manual intervention. This cost-effective solution is particularly significant in the industry, where SSL certificate expiry can lead to lost revenue and reputational damage. By following the guide, organizations can proactively monitor their domain certificates and prevent potential outages.