Etcd - Is it possible to install pubsub using etcd?

Question

I would like to configure etcd / redis to store configuration parameters applicable to all docker containers (right now, only within the same host).

You will also need a pub / sub mechanism, so that issuing certain commands will be easy (for example, "do git pull" for all containers, "disable / enable certain common functions", etc.).

I really like etcd (OOB curl based set / get, 17MB docker image), but at the moment I don’t need various accessibility features, service discovery functions, etc. - maybe for later. As far as I understand, there is no pub / sub api with etcd (the key scan is the closest).

Please indicate if an efficient pub / auxiliary mechanism implementation can be done using etcd. Otherwise, I can continue redis for now.