Waiting on Meteor.user()

Question

If a new users signs up, I take them to the getting started route so they enter can enter a name which is at /gs. I store the name inside a name property of the profile object of the current user. Now if a user who has already entered a name and visits the /gs route I want to redirect them to the root. In iron router, I do this:

Router.route('/gs', {
  name: 'gs',
  onBeforeAction: function() {
    if ( Meteor.user().profile.name ) {
      this.redirect('/');
    } else {
      this.render();
    }
  }
});

Even though this works, it prints out 2 errors to the console. One of them being "Cannot read property 'profile' of undefined" and the lack of this.next(). Any way to fix these problems.

Answer 1

Your route functions and most hooks are run in a reactive computation. This means they will rerun automatically if a reactive data source changes. For example, if you call Meteor.user() inside of your route function, your route function will rerun each time the value of Meteor.user() changes. (Iron.Router Guide: Reactivity)

Hook functions and all functions that get run when dispatching to a route are run in a reactive computation: they will rerun if any reactive data sources invalidate the computation. In the above example, if Meteor.user() changes the entire set of route functions will be run again. (Iron.Router Guide: Using Hooks)

The first time the function is run, Meteor.user() is undefined. Then its value change to an object. As it is a reactive variable, the function is run again, without error this time.

You should check if Meteor.user() is defined before using its properties. Here is a very (maybe too much) exhaustive way of doing so:

if (Meteor.user() !== undefined) {
  // the user is ready
  if (Meteor.user()) {
    // the user is logged in
    if (Meteor.user() && Meteor.user().profile.name) {
      // the name is already set
      this.redirect('/');
    } else {
      this.render();
  } else {
    // the user is not logged in
} else {
  // waiting for the user to be ready
}