How to programmatically monitor if a docker container exited?

Question

I am running multiple named docker containers (200+) on my VM Host. I have a manager script/code that is supposed to manage the containers from the host. I would like to know if there is any event-based mechanism to get notified when a container stops/fails. So that I can restart the stopped container.

One solution I could think of is doing a periodic docker inspect and looking at State.Pid or State.Running to confirm the status.

But,instead of periodic polling, it would be better if the manager is notified with pid/name when a container fails so that, the particular container alone can be restarted.

On a general note, are there ways to programmatically monitor the status of a process from a different process that is not the parent ?

Answer 1

Look at docker events - there is an event for container 'die'.

There is also an http interface to get the same information programmatically - see here

You may want to do a web search for 'docker orchestration' - many projects springing up to manage multiple containers in the way you describe.