redis-graphite.rb

#!/usr/bin/env ruby
require 'socket'
require 'optparse'

# Collect INFO from Redis, report it to Graphite

opts = OptionParser.new do |opts|
  opts.banner = "Usage: redis-graphite.rb redis-host[:redis-port] graphite-host"
  opts.on( '-h', '--help', 'Display this screen' ) do
    puts opts
    exit
  end
end
opts.parse!

redis_server = ARGV.shift
graphite_host = ARGV.shift
unless graphite_host && redis_server
  puts opts
  exit 1
end

class Graphite
  def initialize(host)
    @host = host
  end
 
  def socket
    return @socket if @socket && !@socket.closed?
    @socket = TCPSocket.new(@host, 2003)
  end
 
  def report(key, value, time = Time.now)
    begin
      socket.write("#{key} #{value.to_f} #{time.to_i}\n")
    rescue Errno::EPIPE, Errno::EHOSTUNREACH, Errno::ECONNREFUSED
      @socket = nil
      nil
    end
  end
 
  def close_socket
    @socket.close if @socket
    @socket = nil
  end
end

class String
  def numeric?
    return true if self =~ /^\d+$/
    true if Float(self) rescue false
  end
end  

redis_host, redis_port = *redis_server.split(':')
redis_port ||= 6379 
info = `redis-cli -h #{redis_host} -p #{redis_port} INFO`
exit 2 unless $?.success?

begin
  graphite_client = Graphite.new(graphite_host)
  info.each_line do |line|
    if line.length < 4
      next
    end
    if line.start_with?("#")
      next
    end   
    key, value = *line.split(':')
    # The db* fields have interesing info, but they need extra processing
    if(key.rindex(/db[\d]+/) == 0)
      db_info = value.split(',')
      db_info.each do |db_detail|
        db_key, db_value = *db_detail.split('=')
	db_key = "#{key}-#{db_key}"
	graphite_key = "redis.#{redis_host.gsub('.', '_')}:#{redis_port}.#{db_key}"
	graphite_client.report(graphite_key, db_value) if db_value.numeric?
      end
    else
      graphite_key = "redis.#{redis_host.gsub('.', '_')}:#{redis_port}.#{key}"
      graphite_client.report(graphite_key, value) if value.numeric?
    end
  end
  graphite_client.close_socket
rescue => err 
  puts "Error: #{err}"
  exit 4
  graphite_client.close_socket
end