cairn: a front page for the people you host for, with Gatus status pills

[MorganKryze]

Thanks for Gatus. It's what the status pills on my own front page read from.

I didn't want to reimplement monitoring, so cairn just reads yours. cairn is the page you hand to the non-technical people you host things for, family or a club. You write one YAML file and it serves a static multilingual page, with an optional status pill per service. The pills come from reading your Gatus API server-side, so a visitor's browser never touches Gatus and you don't have to expose it anywhere.

Keeping the two configs in sync was the annoying part. cairn -emit-gatus now prints a Gatus endpoints block derived from the services already declared, and it pairs each Gatus endpoint name with a cairn service id, so when one of them doesn't line up it says so in the log at every poll instead of quietly rendering an empty pill.

• cairn: https://github.com/MorganKryze/cairn (GPL-3.0)
• Demo, with one service left dead so a red pill is visible: https://cairn.libresoftware.cloud
• The Gatus side: https://github.com/MorganKryze/cairn/blob/main/docs/recipes/status.md#gatus