#!/usr/bin/env ruby
require 'socket'
require 'timeout'
require 'rubygems'
require 'net/ssh'

HOSTS = %w{ 10.10.1.10 10.10.1.11 10.10.1.12 10.10.1.13 }

class WatchListener
  attr_accessor :host

  def initialize(host)
    self.host = host
    probe_ports
  end

  def probe_ports
    7000.upto(7006) do |port|
      begin
        socket = TCPSocket.new @host, port
        socket.puts "dummytext\n\ndummytext"
  
        begin
          Timeout.timeout(15) { socket.gets }
        rescue Timeout::Error
          log "%d IS HUNG! RESTARTING..." % port
          restart_listener_on port
        else
          log "%d working fine" % port if ENV['DEBUG']
        end
      rescue Errno::ECONNREFUSED
        log "%d refuses connection"
      end
    end
  end

  def restart_listener_on(port)
    exec %{
      PID=`netstat -a -n -p | grep #{port} | grep LISTEN | awk '{print $7}' | cut -d'/' -f1`
      echo "killing $PID" && kill -9 $PID
    }
  end

  def exec(command)
    log "connecting.."
    Net::SSH.start(host) do |session|
      input, output, error = session.process.popen3(command)
      timeout(20) { log output.read } rescue nil
      input.puts "quit"
    end
    log "done"
  end

  def log(text)
    puts "[%s] (%s) %s" % [ Time.now.strftime("%H:%M:%S"), @host, text ]
  end
end

# Main loop
while true do
  HOSTS.each do |host|
    begin
      WatchListener.new host
    rescue => error
      puts "Exception raised: #{error}"
    end
  end

  print "Sleeping 300 seconds: "
  5.times do |i|
    print "%d .. " % (300 - i * 60)
    STDOUT.flush
    sleep 60
  end
  puts
end