Ruby Webrick: Example of Virtual Host.

webrick_virtualhost_example.rb

# Ruby Webrick example of Virtual Host
#
# Your directory must contain a public/index.html file.
#

require 'webrick'
require 'json'

# Daemonize (production)
#WEBrick::Daemon.start

# Start frontend
server = WEBrick::HTTPServer.new({
                                     :Port => 9000,
                                     :BindAddress => '0.0.0.0'
                                 })

# Start virtual host
host = WEBrick::HTTPServer.new({
                                    :DoNotListen => true,
                                    :Port => nil,
                                    :DocumentRoot =>  __dir__ + '/public',
                                    :ServerName => 'localhost' # Change this to your server in production.
                                })

# Example of query.
def ok(obj, res)
  res.status = 200
  res['Content-Type'] = 'application/json'
  res.body = JSON.pretty_generate(obj).to_s
end

host.mount_proc '/hello' do |req, res|
  obj = {
      :status => 'ok',
      :msg => 'server is online'
  }
  ok(obj, res)
end

# Stop server on interrupt
trap 'INT' do
  server.shutdown
end

# Connect virtual host to frontend
server.virtual_host(host)

# Start frontend
server.start