Watches Mongostat and notifies admins via email if lock % is above threashold

watch_mogno.rake

require 'term/ansicolor'
require 'tlsmail'

task :watch_mongo do

  @notified = false
  file = Tempfile.new('stat_watch')
  begin

    Thread.new('mongostat') do
      # mongostat --rowcount 0 20, will check every 20 seconds
      %x[mongostat --rowcount 0 20 --host #{ENV['MONGO_HOST']} --username #{ENV['MONGO_USERNAME']} --password #{ENV['MONGO_PASSWORD']} --noheaders > #{file.path}]
    end

    sleep(2)

    puts
    puts
    printf "%7s %7s %7s %7s %7s %7s %7s %7s %7s %7s %7s %7s %7s %7s %7s %7s %7s %7s %7s\n",
           'insert' , 'query' ,'update' ,'delete', 'getmore', 'command' ,'flushes', 'mapped' , 'vsize', 'res', 'faults', 'locked %', 'idxmiss%',  'qr|qw'  , 'ar|aw' , 'netIn', 'netOut',  'conn', 'time'

    f = File.open(file,"r")
    f.seek(0,IO::SEEK_END)
    while true do
      select([f])
      line = f.gets
      parse_line(line) if line =~ /^/ && !(line =~ /^connected/)
    end

  ensure
    puts "Closing!"
     file.close
     file.unlink   # deletes the temp file
  end


end

def parse_line(line)
  items = line.split

  inserts  	= items[0]
  query    	= items[1]
  update   	= items[2]
  delete   	= items[3]
  getmore  	= items[4]
  command  	= items[5]
  flushes  	= items[6]
  mapped   	= items[7]
  vsize    	= items[8]
  res      	= items[9]
  faults   	= items[10]
  locked   	= items[11]
  idx_miss 	= items[12]
  qrw     	= items[13]
  arw      	= items[14]
  netIn    	= items[15]
  netOut   	= items[16]
  conn     	= items[17]
  set      	= items[18]
  repl     	= items[19]
  time     	= items[20]

  printf "%7s %7s %7s %7s %7s %7s %7s %7s %7s %7s",
          inserts , query ,update ,delete, getmore, command ,flushes, mapped , vsize, res

  print Term::ANSIColor.bold
  printf '%7s', faults

  l = Float(locked)
  if l > 50
    print Term::ANSIColor.yellow
  elsif l > 70
    print '\a' #beep
    notify_admins
    print Term::ANSIColor.red
  end
  printf '%7s', locked
  print Term::ANSIColor.clear


  printf "%7s %7s %7s %7s %7s %7s %7s\n",
  idx_miss, qrw, arw, netIn, netOut,  conn, time


end

def notify_admins
  if @notified
    puts 'already notified'
  else
    send_email(ENV['GMAIL_USERNAME'])
    @notified = true
  end

end

def send_email(to)

  content = <<EOF
  From: #{ENV['GMAIL_USERNAME']}
  To: #{to}
  Subject: Warning lock levels high
  Date: #{Time.now.rfc2822}

  Something is up, lock levels high
EOF

  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