Is it better to use an observer or a helper?

I am wondering: theoritically, if a helper runs whenever data changes, isn’t it more efficient to create observers? Eg:

Template['User.profile'].onCreated(function () {
  this.user = new ReactiveVar(false);
  this.observers = [];

  const userObserver = Meteor.users.find({
    _id: Router.current().params._id
    added: (doc) => {
      const profileObs = Profiles.find(doc.profile).observe({
        added: (profile) => {
          this.user.set(_.extend(this.user.get(), {
            profile: profile
        changed: (profile) => {
          this.user.set(_.extend(this.user.get(), {
            profile: profile

Template['User.profile'].onDestroyed(function () {
  this.observers.forEach((obs) => obs.stop());

Wouldn’t this be faster and look more elegant?

What is this code trying to accomplish?

It is super hard to tell from that code, which implies for me that it might not be a good pattern.

1 Like

Essentially, take a data structure like this (from Meteor.users).

  _id: '1234',
  emails: [{
    address: '',
    verified: true
  profile: '5678'

So then it will create a few observers on every foreign key, and update the reactive var when any of them change

I don’t think this is actually worthwhile. Even if it were more efficient, I doubt your app’s performance would be bottlenecked by this situation.