By default Meteor Streams does not have any reactive capabilities. But using it with local only collections, we can get some form of reactivity.

In the following example, we’ll try render server generated notifications using reactive collections.

Add following content to home.html

Add following content to reactive-streams.js. See inline comments for more information.

notifications = new Meteor.Stream('server-notifications');

if (Meteor.isClient) {
  //create a client only collection
  notificationCollection = new Meteor.Collection(null);

  //listen to the stream and add to the collection
  notifications.on('message', function(message, time) {
    notificationCollection.insert({
      message: message,
      time: time
    });
  });

  //render template with the collection
  Template.body.helpers({
    'messages': function() {
      return notificationCollection.find();
    },

    'dateString': function() {
      return new Date(this.time).toString();
    }
  });
}

if (Meteor.isServer) {
  //allow any connected client to listen on the stream
  notifications.permissions.read(function(userId, eventName) {
    return true;
  });

  //notify clients with a message per every second
  setInterval(function() {
    notifications.emit('message', 'Server Generated Message', Date.now());
  }, 1000);
}