I need to find a way to show if a user is currently online, or not. I'm using the HackathonStarter project (https://github.com/sahat/hackathon-starter), so have all the options included with that framework. In the User model, I want to add a Boolean field in order to show if the user is online or not, is there anything wrong with using Mongoose TTL for this? Example, every time a user makes a request, the online status field would be refreshed to true, I'd set it's TTL for 5 min, so after 5 minutes of inactivity the field would expire, where I would then use onReap in (https://github.com/aheckmann/mongoose-ttl) to set it back to false. Anything wrong with doing it this way?