如何等待Meteor.user（）在Template onRendered中定义

Question

I am working on a Meteor project and I need to access some information stored in a user's profile to make a map on the page. However, when I try to access Meteor.user(), I receive undefined because when the function is called, Meteor.user() has not been loaded.

Template.body.onRendered () ->
    console.log Meteor.user()
    address = Meteor.user()['profile']['address']

    GoogleMaps.ready 'studyMap', (map) ->
        # maps code that relies on address

Because Meteor.user() is not defined, I am not able to get the map to work. How can I wait for Meteor.user() to be defined?

Answer 1

I think your going to need an asynchronous callback to load the map only when address = Meteor.user()['profile']['address'] loads. As far as how to implement this, I'm not really sure.

Answer 2

One of my apps has to do something similar to wait on a subscription. I defined the waitOn() handler in my router.

Router.map(function(){
  this.route('Brocator', {
    path: '/',
    template: 'brocator',
    waitOn: function() {
      return (Meteor.subscribe('people', this.params._gridId)
        && Meteor.subscribe('gridlog', this.params._gridId) );
    },
    data: function() {
      var gridId = this.params._gridId;
      return (People.find({gridId: gridId})
        && GridLog.find({gridId: gridId}));
    },
    fastRender: true
  }),
  ... other routes deleted for clarity
})

You may decide to use something along the lines of

return Meteor.user() != 'undefined';

in your waitOn() handler.

Answer 3

Posted an answer for meteor/react here however the same can be done with blaze. I am not familiar with blaze but within your Template.body.onRendered function you can listen to make sure that the login services are configured before rendering anything.

Tracker.autorun(() => {
  if (Accounts.loginServicesConfigured()) {
    // accounts is ready go ahead and render
  } else {
    // still waiting show loading spinner
  }
});

I would recommend extracting this logic out to a higher level so that you don't keep repeating the same code.