The client side of basic HTTP authentication on your docker daemon (to be used with https://github.com/docker-in-practice/docker-authenticate).
Run with:
docker run -d -p 127.0.0.1:12375:12375 dockerinpractice/docker-authenticate-client \
targetip:2375 username:password
(note that targetip must not be localhost/127.0.0.1 - use the external IP of your host if you want to just try it out)
You can then use docker with
docker -H localhost:12375 ps