How to make a simple countdown timer in meteor, with timer on server and clock on client

Question

I was wondering how to make a simple countdown timer that would countdown on the server, but show how long was left on the client.

Answer 1

Server:

timeToClear.remove({}); //Removes the previous time calls
Meteor.setInterval(function(){ //The Actual Countdown
  Messages.insert({
    name: "[Server]",
    message: "<div class='animated infinite flash'>Attention! Chat will be cleared in 15 seconds!<br>Note: Chat is cleared every 12 hours</div>",
    time: moment().format('MMMM Do , h:mm a'),
    uid: Messages.find().fetch().length + 1,
    email: "Server Function"
  });
  Meteor.setTimeout(function () {
    Messages.remove({});
  }, 15000);
}, 28800000); 
time = 28000000; //Sets the ammount of time to countdown
uid = 0;
Meteor.setInterval(function(){ //The part that allows the client to see it
  console.log(uid);
  timeToClear.insert({
    time: time,
    uid: uid
  })
  time = time - 1000;
  uid = uid + 1;
  if(time === 0){
    time = 28000000; //Resets time after countdown is complete
    uid = 0;
    timeToClear.remove({}); //Removes all previous time calls
  }


}, 1000)

Client:

  Template.countdown.helpers({
    timer: function (){
      x = timeToClear.find({}, { sort: { uid: -1}}).fetch()[0].time; //Gets the highest (newest) uid, and gets the time from it
      var tempTime = moment.duration(x); //Converts it into a nicer format using moment
      var hours = tempTime.hours(); 
      var minutes = tempTime.minutes();
      var seconds = tempTime.seconds();
      return "Time till messages are cleared: " +hours + ":" + minutes + ":" + seconds; //Returns it to helper
    }


  })

Then simply call the helper on the client in a template called countdown!