A small ruby script to aggregate output of mongotop MongoDB command

mongotop_handller.rb

# Usage:
#    mongotop --host host --port port | ruby mongotop_handler.rb

require 'curses'
include Curses

def print_stats stats, time_elapsed
  h = stats.length
  w = 130
  win = Window.new(h + 6, w + 6,
                   5, (cols - w) / 2)
  win.box(?|, ?-)
  
  msg = "mongotop running totals (elapsed #{time_elapsed.to_i} secs)"
  win.setpos 2, (w - msg.length) / 2
  win.addstr msg

  sorted = stats.sort{|lhs, rhs| rhs[1][:total] <=> lhs[1][:total] }
  sorted.each_with_index do |(k, v), idx|
    win.setpos(4 + idx, 3)
    win.addstr(k.rjust(60, ' '))

    win.setpos(4 + idx, 66)
    t, r, w = v.values_at(:total, :read, :write)
               .map(&:to_s)
               .map{|s| "#{s} ms".ljust(15, ' ')}
               
    win.addstr "total: #{t}read: #{r}write: #{w}"
  end
  win.refresh
  win.close
end

def handle_line result, line
  parts = line.split(/\s/).reject(&:empty?)
  stop_list = %w[connected ns]
  return if stop_list.include?(parts[0]) || parts.empty?

  name = parts.shift
  total, read, write = parts.map(&:to_i)

  result[name] ||= {total: 0, read: 0, write: 0}

  result[name][:total] += total
  result[name][:read] += read
  result[name][:write] += write
end


init_screen

start_time = Time.now
result = {}

begin
  crmode
  while line = gets
    handle_line result, line
    print_stats result, Time.now - start_time
  end
  
  `say quitting`
  sleep(5)
ensure
  close_screen
  p result
end