Answers for "First, get the docker host’s ip:"

How to get a Docker container's IP address from the host

docker inspect some-rabbit
you will get the ip address and port number from hear.
http://172.17.0.2:15672/

docker get ip all container

docker ps -q | xargs -n 1 docker inspect --format '{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}} {{ .Name }}' | sed 's/ // /'