watchdog.rb

  require 'atomic'

  class Watchdog
    def initialize(description)
      @description = description
      @finished = Atomic.new(false)
      @thread = Thread.new do
        run_monitor
      end
    end

    def finished!
      @finished.update {|_| true}
    end

    def run_monitor
      loop do
        sleep 5

        if @finished.value
          break
        else
          $stderr.puts "#{Time.now} Request still running: #{@description}"
        end
      end
    end
  end