draft for parsing munin data

em_munin.rb

require 'eventmachine'

module Munin
  include EM::Deferrable

  Delimiter = "\n".freeze
  End = '.'.freeze
  def receive_data(data)
    (@buffer||='') << data
    while index = @buffer.index(Delimiter)
      line = @buffer.slice!(0,index+1)
      process_line line
    end
  end

  def connection_completed
    succeed
  end
  
  def process_line(line)
    case line.strip
    when /^#/ # comment
    when End
      handle_callback if @cb
      @data = {}
    # e.x load.value 1.3
    when /^([^\.]+)\.value (.+)$/
      @data ||= {}
      @data[$1] = $2
    else
      raise "Don't know how to #{line}"
    end
  end

  def handle_callback
    @cb.call @data.size == 1 ? @data.values.first : @data
  end

  def method_missing(command, &block)
    callback {
      @cb = block
      send_data "fetch #{command}"
      send_data Delimiter
    }
  end
end

EM::run do
  mun = EM.connect '127.0.0.1', 4949, Munin
  mun.load { |load| puts load }
end