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[:port] graphite_host [graphite_prefix(e.g. redis.cluster-name.server-identifier)]"
  opts.on( '-h', '--help', 'Display this screen' ) do
    puts opts
    exit
  end
end
opts.parse!
 
redis_server       = ARGV.shift
graphite_host      = ARGV.shift
graphite_namespace = 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`
# if namespace is not given, it uses redis.host_port as defaut namespace 
graphite_namespace = graphite_namespace || "redis.#{redis_host.gsub('.', '_')}_#{redis_port}"
exit 2 unless $?.success?
 
begin
  graphite_client = Graphite.new(graphite_host)
  info.each_line do |line|
    next if line.length < 4 || line.start_with?("#") 

    key, value = *line.split(':')
    # Parse db* and slave*
    if(key.rindex(/(db|slave)[\d]+/) == 0)
      tmp_info = value.split(',')
      tmp_info.each do |tmp_detail|
        tmp_key, tmp_value = *tmp_detail.split('=')
        tmp_key = "#{key}-#{tmp_key}"
        graphite_key = "#{graphite_namespace}.#{tmp_key}"
        graphite_client.report(graphite_key, tmp_value) if tmp_value.numeric?
      end
    else
      graphite_key = "#{graphite_namespace}.#{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