Watches heroku router logs and summerizes and notifies

heroku_watcher.rake

# Excute by the following:
# bundle exec rake GMAIL_USERNAME=name@example.com GMAIL_PASSWORD=password watch_heroku
task :watch_heroku do

  puts "need to set GMAIL_USERNAME and GMAIL_PASSWORD environment variables" unless (ENV['GMAIL_USERNAME'] && ENV['GMAIL_PASSWORD'])

  @critical_notified = false
  @warning_notified = false

  @total_lines = 0
  @total_service = 0
  @total_wait = 0
  @total_queue = 0
  @total_errors = 0
  @max_service = 0

  @mutex = Mutex.new

  # print headers
  puts
  puts
  printf "%7s %7s %7s %7s %7s %7s %40s\n",
         'ops', 'service', 'wait', 'queue', 'max_serv', 'errors', 'time'

  threads = []
  threads << Thread.new('heroku_logs') do
    IO.popen("heroku logs --ps router --tail --app #{ENV['APP_NAME']}") do |f|
      while line = f.gets
        parse_heroku_line(line) if line =~ /^/
      end
    end
  end

  # every 60 seconds print out averages, and other stats and reset memos
  threads << Thread.new('summarize') do
    while true do
      sleep(60)
      average_service = @total_lines > 0 ? @total_service / @total_lines : 'N/A'
      average_wait = @total_lines > 0 ? @total_wait / @total_lines : 'N/A'
      average_queue = @total_lines > 0 ? @total_queue / @total_lines : 'N/A'

      color_print @total_lines
      color_print average_service, warning: 1000, critical: 10_000
      color_print average_wait, warning: 10, critical: 100
      color_print average_queue, warning: 10, critical: 100
      color_print @max_service, warning: 10_000, critical: 20_000
      color_print @total_errors, warning: 1, critical: 10
      color_print Time.now, length: 40
      printf "\n"

      # if any errors or average service about a threshold notify
      check_and_notify(average_service, @total_errors)

      #reset
      @mutex.synchronize do
        @total_service = @total_lines = @total_wait = @total_queue = @total_errors = @max_service = 0
      end
    end
  end

  threads.each { |t| t.join }

end

def color_print(field, options ={})
  options[:length] = 7 unless options[:length]
  if options[:critical] && is_number?(field) && Integer(field) > options[:critical]
    print "\a" #beep
               #  notify_critical
    print Term::ANSIColor.red
    print Term::ANSIColor.bold
  elsif options[:warning] && is_number?(field) && Integer(field) > options[:warning]
    print Term::ANSIColor.yellow
  end
  printf "%#{options[:length]}s", field
  print Term::ANSIColor.clear
end

def parse_heroku_line(line)
  # 2012-07-05T20:24:10+00:00 heroku[router]: GET my-app.com/pxl/4fdbc97dc6b36c0030001160?value=1 dyno=web.14 queue=0 wait=0ms service=8ms status=200 bytes=35

  # or if error

  #2012-07-05T20:17:12+00:00 heroku[router]: Error H12 (Request timeout) -> GET my-app.com/crossdomain.xml dyno=web.4 queue= wait= service=30000ms status=503 bytes=0

  items = line.split

  if line =~ /Error/
    @total_errors += 1
  else


    time = items[0]
    process = items[1]
    http_type = items[2]
    url = items[3]
    dyno = items[4].split('=').last if items[4]
    queue = items[5].split('=').last.sub('ms', '') if items[5]
    wait = items[6].split('=').last.sub('ms', '') if items[6]
    service = items[7].split('=').last.sub('ms', '') if items[7]
    status = items[8].split('=').last if items[8]
    bytes = items[9].split('=').last if items[9]

    if is_number?(service) && is_number?(wait) && is_number?(queue)
      @mutex.synchronize do
        @total_lines +=1
        @total_service += Integer(service) if service
        @total_wait += Integer(wait) if wait
        @total_queue += Integer(queue) if queue
        @max_service = Integer(service) if Integer(service) > @max_service
      end
    end


  end

end

def is_number?(string)
  _is_number = true
  begin
    num = Integer(string)
  rescue
    _is_number = false
  end
  _is_number
end


def check_and_notify(average_service, errors)
  if average_service > 10_000 || errors > 10
    notify_critical
  elsif average_service > 600 || errors > 5
    notify_warning
  end
end


def notify_kaboom
  Thread.new('notify_admins') do
    # send emails
  end
end

def notify_critical
  unless @critical_notified
    Thread.new('notify_admins') do
      # send emails
    end
    @critical_notified = true
  end
end

def notify_warning

  unless @warning_notified
    Thread.new('notify_admins') do
      # send emails
    end
    @warning_notified = true
  end

end


def send_email(to, msg)

  content = <<EOF
  From: #{ENV['GMAIL_USERNAME']}
  To: #{to}
  Subject: #{msg}


  #{msg}
EOF

  content = [
      "From: Heroku Dyno Watcher <#{ENV['GMAIL_USERNAME']}>",
      "To: #{to}",
      "Subject: #{msg}",
      "",
      "#{msg}"
  ].join("\r\n")

  Net::SMTP.enable_tls(OpenSSL::SSL::VERIFY_NONE)
  Net::SMTP.start('smtp.gmail.com', 587, 'gmail.com', ENV['GMAIL_USERNAME'], ENV['GMAIL_PASSWORD'], :login) do |smtp|
    smtp.send_message(content, ENV['GMAIL_USERNAME'], to)
  end


end

adding mutex