#!/usr/bin/env ruby

# Gathers Redis SLOWLOG statistics and submits them to Riemann.

require File.expand_path('../../lib/riemann/tools', __FILE__)

class Riemann::Tools::RedisSlowlog
  include Riemann::Tools
  require 'redis'

  opt :redis_url,      "Redis URL",                        :default => 'redis://127.0.0.1:6379/'
  opt :redis_password, "Redis password",                   :default => ''
  opt :slowlog_len,    "Number of SLOWLOG entries to get", :default => 10
  opt :slowlog_reset,  "Reset SLOWLOG after querying it",  :default => false

  def initialize
    @redis = ::Redis.new(url: opts[:redis_url])

    @slowlog_len   = opts[:slowlog_len]
    @slowlog_reset = opts[:slowlog_reset]

    @redis.auth(opts[:redis_password]) unless opts[:redis_password] == ''
  end

  def tick
    @redis.slowlog("GET", @slowlog_len).each do |id, timestamp, us, cmd|
      data = {
        :host        => @redis.client.host,
        :service     => "redis",
        :time        => timestamp,
        :metric      => us.to_f,
        :state       => 'warning',
        :tags        => ['redis', 'slowlog'],
        :description => cmd.inspect
      }
      report(data)
    end

    @redis.slowlog("RESET") if @slowlog_reset
  end

end

Riemann::Tools::RedisSlowlog.run