Occasionally in your automation infrastructure, you want an event to trigger a notification. For example, every time a chef run fails, send an alert. Or every time a webserver reboots, send an email.
Chef handles this beautifully with event handlers.
Basically an event handler is a ruby script that chef calls on a defined trigger.
In my infrastructure, we are adopting slack for both communication and notifications. Slack is simple, beautiful and powerful.
There is a community of chef handlers for many external services such as:
Here is how simple it is to add slack notifications to a cookbook.
And here is what it looks like in slack