chat.rb

require 'socket'

# Use your INTERNAL ip
me = { ip: '192.168.1.205', port: 55_555, name: 'Gabe' }

# Use your friend's EXTERNAL ip
friend = { ip: '50.187.42.170', port: 5_555, name: 'Edward' }

BasicSocket.do_not_reverse_lookup = true

sender = UDPSocket.new
sender.setsockopt(Socket::SOL_SOCKET, Socket::SO_BROADCAST, true)

receiver = UDPSocket.new
receiver.bind(me[:ip], me[:port])
receiver.setsockopt(Socket::SOL_SOCKET, Socket::SO_BROADCAST, true)

send_thread = Thread.new(me, friend, sender) do |me, friend, sender|
  loop do
    puts "Inside send_thread"

    print "> "
    data = $stdin.gets.chomp
    send_message(data, me, friend, sender)
    break if data == '/quit'

    Thread.pass
  end
end

receive_thread = Thread.new do
  loop do
    puts "Inside receive_thread"

    data, _ = receiver.recvfrom(1024)
    $stdout.print("#{friend[:name]}: #{data}\n")
    break if data == '/quit'

    Thread.pass
  end
end

def send_message(message, me, friend, sender)
  $stdout.print "\rFrom you: #{me[:name]}: #{message}\n"
  sender.send(message, 0, friend[:ip], friend[:port])
end

receive_thread.join
send_thread.join

sender.close
receiver.close