In my post about two years ago I showed how to monitor SSL certificates with Zabbix.
In the meantime the scripts/templates have been enhanced, with some small corrections/bugfixes.
One notable new feature is the possiblity to monitor SSL certificates which are delivered by SNI, which means you can have multiple SSL certificates available on the same IP/Port combination.
This is a critical feature, to better use the available IPv4 addresses.
The enhanced templates and scripts are now available via Github, which allows you to open issues if something is not working in your environment or contribute to new features as well.
I'm interested to hear about your use cases and feedbacks.