Im also having problems. It was working at part 2, but the part 3 which introduces docker swarm doesnt work. My docker-compose.yml and Dockerfile are the same as the tutorial. Im getting the usual connected refused at localhost:4000 and localhost:80.
I am using ubuntu 16.04. I have apache installed so it was using port 80, but i put down the apache service and the swarm still doenst work. The services are up though, because using comands like docker container ls, docker service ls, and docker inspect respond just like the tutorial. So i think its a port mapping issue.