How to clear Timeinterval

Question

I have encountered a problem with my counter. I don't know why but the clearInterval(timeinterval) doesn't fire. If i put a console.log statement for t it is going to -1, -2, etc.. why isn't the counter stopping?

  Template.decision.onRendered(function(){
     timeinterval = setInterval(function () {
    var endtime = '2016/02/10'     
      Meteor.call("getCurrentTime", function (error, result) {
        Session.set("time", result);
        var t = getTimeRemaining(endtime);
        Session.set("t", t);
      });
    }, 1000);
  });

  function getTimeRemaining(endtime){
    var t = Date.parse(endtime) - Session.get('time');
    var seconds = ("0" + Math.floor( (t/1000) % 60 )).slice(-2);
    var minutes = ("0" + Math.floor( (t/1000/60) % 60 )).slice(-2);
    var hours = ("0" + Math.floor( (t/(1000*60*60)) % 24 )).slice(-2);
    var days = Math.floor( t/(1000*60*60*24) );
    console.log(t);

    if(t <= 0) {
      clearInterval(timeinterval);
    }
return {
  'total': t,
  'days': days,
  'hours': hours,
  'minutes': minutes,
  'seconds': seconds
};
}

And on my server:

  Meteor.methods({
    'getCurrentTime': function (){
      return Date.parse(new Date());
    }
  });

Answer 1

if(t <= 0 && timeinterval) {
  clearInterval(timeinterval);
}

To not to have duplicate timers, either you can cancel the previous interval in the line before you set the new timer, or you can do:

if (!timeinterval) {
    timeinterval = setInterval(function () {
        timeinterval = null;
    }, delay);
}

But this can be tricky when you have concurrency.