sneakers configuration

Sneakers.configure(
  heartbeat: 2,
  exchange: 'sneakers',
  exchange_type: :direct,
  durable: true,
  workers: Rails.application.secrets.sneakers_processes,
  threads: Rails.application.secrets.sneakers_threads,
  prefetch: Rails.application.secrets.sneakers_threads, # this is not a typo: the doc says it's good to match prefetch and threads values
  timeout_job_after: 60,
  share_threads: true, # both options are supported by `after_hook` hereafter
  hooks: {
    before_fork: -> {
      ActiveSupport.on_load(:active_record) do
        ActiveRecord::Base.connection_pool.disconnect!
        StatsBase.connection_pool.disconnect!
        Sneakers.logger.info('Disconnected from ActiveRecord')
      end
    },
    after_fork: -> {
      def determine_db_pool_size
        worker_classes     = Sneakers::Utils.parse_workers(ENV["WORKERS"]).first
        threads_per_worker = Rails.application.secrets.sneakers_threads

        if Sneakers.const_get(:CONFIG)[:share_threads]
          3 + worker_classes.count * 3 + threads_per_worker
        else
          3 + worker_classes.count * 3 + worker_classes.count * threads_per_worker
        end
      end

      def reconnect_default_database(db_pool_size)
        ActiveRecord::Base.establish_connection(Rails.application.config.database_configuration[Rails.env].merge("pool" => db_pool_size))
      end

      def reconnect_stats_database(db_pool_size)
        if Rails.application.secrets.stats_database_url.present?
          StatsBase.establish_connection(Rails.application.secrets.stats_database_url + "?pool=#{db_pool_size}")
        elsif Rails.application.config.database_configuration.has_key? "stats_#{Rails.env}"
          StatsBase.establish_connection(Rails.application.config.database_configuration["stats_#{Rails.env}"].merge("pool" => db_pool_size))
        else
          raise StandardError.new("Stats database not properly configured.")
        end
      end

      ActiveSupport.on_load(:active_record) do
        db_pool_size = determine_db_pool_size
        reconnect_default_database(db_pool_size)
        reconnect_stats_database(db_pool_size)
        Sneakers.logger.info("Connected to ActiveRecord")
      end
    }
  }
)