Storing the return value of node.js setTimeout in redis

Question

I\'m using setTimeout in Node.js and it seems to behave differently from client-side setTimeout in that it returns an object instead of a number. I wan

Answer 1

This code is used when the timeouts need not be persistent across server restarts

var timeouts = {};

app.get('/', function (req, res) {
  var index = timeouts.length;
  timeouts[index] = setTimeout(console.log, 1000000, req.user.name);

  redis.set('timeout:' + req.user.name, index, function (err, reply) {
    res.end();
  });
});

app.get('/clear', function (req, res) {
  redis.get('timeout:' + req.user.name, function (err, index) {
   clearTimeout(timeouts[index]);
   delete timeouts[index];
   redis.delete('timeout:' + req.user.name);
   res.end();
  });
});

If you need timeouts to be persistent across server restarts, then you might need to store _idleStart and _idleTimeout values for every timer in the redis, and load them up everytime you server restarts

app.get('/', function (req, res) {
  var timeout = setTimeout(console.log, 1000000, req.user.name);
  var time = timeout._idleStart.getTime() + timeout._idleTimeout;

  redis.set('timeout:' + req.user.name, time, function (err, reply) {
    res.end();
  });
});

app.get('/clear', function (req, res) {
  redis.delete('timeout:' + req.user.name);
  res.end();
});

// Load timeouts on server start
// *I know this is not the correct redis command*
// *It's not accurate, only approx*
redis.get('timeout:*', function (err, vals) {
  vals.forEach(function (val) {
    var time = val - new Date().getTime();
    setTimeout(console.log, time, username)
  });
});