title: How would you monitor how much time has passed when the user is not on the site? (Laravel/PHP)
body: <p>Consider the following example:</p>
  
  <p>User click a button, the button sends some kind of request back to start a task that completes after 30 minutes. On the front end, we show a timer counting down the 30 minutes. </p>
  
  <p>If the user stays for thirty minutes, then something else happens. If the user leaves, logs out or closes the browser, the timer should still be running, but this time on the back end.</p>
  
  <p>I know in this case I would use Laravel's Event/notification system to handle the whole button is clicked, lets set up the timer and notify when done. But how do I monitor that ok X happened while you were gone and when you log back in or come back (after 30 minutes) theres a notification</p>
  
  <p>Essentially how do you replicate "those games" that have timers and allow you to leave and come back and the timer (over real world time) has gone down?</p>