https://gitlab.com/kennethreitz/httpbin/-/tree/master/httpbin
docker run -p 4567:80 -p 9090:80 kennethreitz/httpbin
https://github.com/mendhak/docker-http-https-echo https://hub.docker.com/r/mendhak/http-https-echo
docker run -p 9090:80 -p 9443:443 --rm -t mendhak/http-https-echo
boot on multiple ports
bundle install
RACK_ENV=development bundle exec unicorn --config-file unicorn_conf.rb config.ru
# if you have trouble booting unicorn try
cat log/*
boot on thin
bundle install
RACK_ENV=development bundle exec thin start --port 4567 --rackup config.ru -a0.0.0.0 --debug --log -
for developing
RACK_ENV=development bundle exec rackup config.ru --port 4567
For udp ports using Socket.udp_server_loop
rbenv exec bundle exec ./udp_listener.rb