TCP binary protocol server/client (inspired/borrowed from https://gist.github.com/omnisis/3998752)

protocol.rb

require 'bindata'

class CustomProtocol < BinData::Record
  endian  :big
  stringz :command_word
  uint32  :op1
  uint32  :op2
end

tcp_client.rb

require 'socket'
require_relative 'protocol'

$port = 9999
$host = 'localhost'

def make_request(cmd, a,b)
  add_request = CustomProtocol.new
  add_request.command_word = cmd
  add_request.op1 = a
  add_request.op2 = b
  add_request
end

def print_answer(sock)
  msg = sock.gets
  puts "server responded: #{msg} " 
end

def send_request(sock, data)
  sock.puts(data)
end

1000.times do |i|
    puts i

    s = TCPSocket.new($host, $port)
    req1 = make_request("ADD",i ,i)

    puts "sending add request over socket ..."

    send_request(s, req1.to_binary_s)
    print_answer(s)

    s.close


    s = TCPSocket.new($host, $port)
    req2 = make_request("MULT",i, i)

    puts "sending multiply request over socket ..."

    send_request(s, req2.to_binary_s)
    print_answer(s)
end

tcp_server.rb

require 'socket'
require_relative 'protocol'  # needed for custom binary protocol
port = 9999

puts "Started TCP server on #{port}..."

Socket.tcp_server_loop(port) { |msg|
  proto = CustomProtocol.new
  proto.read(msg)
  #puts proto.command_word

  if proto.command_word == "ADD" 
    #puts "Received ADD command"
    result = (proto.op1 + proto.op2)
    #puts result
    msg.puts(result.to_s)

  elsif proto.command_word == "MULT"
    #puts "Received MULTIPLY command"
    result = (proto.op1 * proto.op2)
    msg.puts(result.to_s)

  else
    puts "Received uknown cmd msg: #{proto.command_word} ..."
  end
}