Grab a screenshot of my Rigol 1054 off the LAN and convert it to png

rigol_screenshot.rb

#!/usr/bin/env ruby

require 'csv'
require 'socket'
require 'tempfile'

IP = '192.168.0.24'
PORT = 5555

class Screenshot
  TEMPFILE = %w{scope bmp}
  Scope = Struct.new(:name, :model, :serial, :firmware)

  def initialize(host, port)
    @sock = TCPSocket.new(host, port)
  end

  def identify
    sock.puts('*IDN?')
    response = CSV.parse(sock.gets.chomp).flatten
    Scope.new(*response)
  end

  def grab(filename = generate_filename)
    filename.tap do |filename|
      temp_file = Tempfile.new(TEMPFILE)
      File.open(temp_file.path, 'wb') do |fp|
        fp.write(read_screenshot)
      end
      system("convert #{temp_file.path} #{filename}")
      exit_fail unless $?.success?
      puts "[+] Wrote #{filename}"
    end
  end

  private
  attr_reader :sock

  def read_screenshot
    sock.puts(':DISP:DATA?')
    sock.read(1)
    sock.read(read_integer(read_integer(1)))
  end

  def read_integer(n)
    sock.read(n).to_i
  end

  def generate_filename
    model = identify.model
    time = Time.now.strftime('%F.%H:%M:%S')
    [model, time, 'png'].join('.')
  end

  def exit_fail
    STDERR.puts('Failed to convert to png')
    exit 1
  end
end

Screenshot.new(IP, PORT).grab