Shell function to tail a log file for a specific string for a specific time

Question

I need to the following things to make sure my application server is

1. Tail a log file for a specific string
2. Remain blocked until that string is printe

Answer 1

time=0
found=0
while [ $time -lt 1200 ]; do
  out=$(tail logfile)
  if [[ $out =~ specificString ]]; then
    found=1
    break;
  fi  
  let time++
  sleep 1
done
echo $found