Containers dependency with etcd keys

Question

I want to have containers dependency with etcd keys. Let's say I have a key "key" with value of "x", if that key changes to "y", I want to kill a specific container (which will automaticlly restart because it have a unit with always restart). I'm not really sure how to achieve this.

This is because if some keys change, I need to start a chain of actions to restart few container (in a specific order).

Any ideas?

Answer 1

You'll have to write some software to do this to encode your specific ruleset. This could be as simple as a bash script that is looping over etcdctl (or curl) and systemctl, or a Go program thats communicating with systemd over dbus.

Docs on Waiting for a change on an etcd key.