check-redis.rb

#!/usr/bin/env ruby

require 'optparse'
require 'rubygems'
require 'redis'

options = {:host => 'localhost',
          :port => 6379,
          :db => 0,
          :password => nil,
          :timeout => 3}

optparser = OptionParser.new do |opt|
  opt.banner = "Usage: #{$0} -H <hostname> [options]"
  opt.on('-H', '--host HOSTNAME', 'Hostname') {|o| options[:host] = o if o }
  opt.on('-p', '--port PORT', 'Port (Default: "6379")') {|o| options[:port] = o if o }
  opt.on('-P', '--password PASSWORD', 'Password (Default: blank)') {|o| options[:password] = o if o }
  opt.on('-T', '--timeout', 'Timeout in seconds (Default: 3)') {|o| options[:timeout] = o if o }
end

args = []
begin
  args = optparser.parse!
rescue => e
  $stderr.print e
  $stderr.print optparser
  exit 0
end

class CheckRedis

  def initialize(opts)
    @keys = %w(last_save_time redis_version total_connections_received connected_clients total_commands_processed connected_slaves uptime_in_seconds used_memory_human uptime_in_days changes_since_last_save)
    @r = Redis.new(opts)
    gather_stats
  rescue Errno::ECONNREFUSED
    print "CRITICAL - Connection refused.\n"
    exit 2
  rescue Errno::ENETUNREACH
    print "CRITICAL - Network is unreachable.\n"
    exit 2
  rescue Errno::EHOSTUNREACH
    print "CRITICAL - No route to host.\n"
    exit 2
  end

  private

  def gather_stats
    @info = @r.info
    parse_info
    output_status
    print @status
    exit 0
  end

  def output_status
    @status = "OK - version: #{@redis_version} | memory: #{@used_memory_human}\n"
  end

  def parse_info
    @info.each do |key,value|
      send("parse_#{key}".to_sym, value) if @keys.include? key.to_s
    end
  end

  def parse_last_save_time(value)
    @last_save_time = value
  end

  def parse_redis_version(value)
    @redis_version = value
  end

  def parse_total_connections_received(value)
    @total_connections_received = value
  end

  def parse_connected_clients(value)
    @connected_clients = value
  end

  def parse_total_commands_processed(value)
    @total_commands_processed = value
  end

  def parse_connected_slaves(value)
    @connected_slaves = value
  end

  def parse_uptime_in_seconds(value)
    @uptime_in_seconds = value
  end

  def parse_used_memory_human(value)
    @used_memory_human = value
  end

  def parse_uptime_in_days(value)
    @uptime_in_days = value
  end

  def parse_changes_since_last_save(value)
    @changes_since_last_save = value
  end
end

CheckRedis.new(options)