scaler.rb

require 'bundler/setup'
Bundler.require

require './lib/librato_wrapper'
require './lib/heroku_wrapper'
require './lib/sidekiq_wrapper'
require './lib/new_relic_wrapper'

module Scaler
  extend self

  def stats_workers
    heroku = HerokuWrapper.new('sv-stats', range: 1..12)
    sidekiq = SidekiqWrapper.new('stats', queues: %w[stats stats-slow])
    historic = sidekiq.historic(5)
    n = heroku.ps_n(:worker)
    if historic.sum == 0
      n -= 1
    elsif historic.sum > 2500 && historic[-1] > historic[-2]
      n += 1
    end
    heroku.ps_scale(:worker, n)
  end

  def my_workers
    heroku = HerokuWrapper.new('sv-my', range: 1..4)
    sidekiq = SidekiqWrapper.new('stats', queues: %w[my my-high my-loader my-low my-mailer])
    heroku.ps_scale(:worker, sidekiq.size > 100 ? heroku.range.max : heroku.range.min)
  end

  def data_webs
    new_relic = NewRelicWrapper.new(1898958) # data.sv.app
    heroku = HerokuWrapper.new('sv-data', range: 2..5)
    heroku.ps_scale(:web, (new_relic.throughput / 2500.0).ceil)
  end

  def scout_workers
    heroku = HerokuWrapper.new('sv-scout')
    sidekiq = SidekiqWrapper.new('scout', queues: %w[scout])
    heroku.ps_scale(:worker, sidekiq.size > 0 ? 1 : 0)
  end

  def www_workers
    heroku = HerokuWrapper.new('sv-www')
    sidekiq = SidekiqWrapper.new('www', queues: %w[www])
    heroku.ps_scale(:worker, sidekiq.size > 0 ? 1 : 0)
  end
end

module Clockwork
  every(30.seconds, 'Stats workers')   { Scaler.stats_workers }
  every(15.seconds, 'My workers')      { Scaler.my_workers }
  every(30.seconds, 'Data webs')       { Scaler.data_webs }
  every(30.seconds, 'Scout workers')   { Scaler.scout_workers }
  every(30.seconds, 'Www workers')     { Scaler.www_workers }
  every(1.minute,   'Librato Metrics') { LibratoWrapper.instance.submit }
end