Meteor: iron-router => waitOn without subscribe

Question

i want a loading template to appear before the site has all data to be rendered.

And after the serverside Method gives me the Data(from an API [async]) via Meteor.ca

Answer 1

I know you've accepted the answer about getting this done via creating a psuedo-publication, but I think there's a more fitting solution.

The good folks at ars-nebula already did the work to make a Meteor method call wait-able using the https://github.com/arsnebula/reactive-promise/ library.

Get the promise via:

var $dep = new $.Deferred();
Meteor.call("myMethod", function(err, result) {
  if (err) { $dep.reject(err); }
  $dep.resolve(result);
});

var promise = $dep.promise();

Then wait on it via

Router.route('/route', {
  "loadingTemplate": loading,
  "waitOn": function() {
    return ReactivePromise.when("myTask", $def1.promise(), $def2.promise());
  },
  "action": function() {
    this.render("myTemplate");
  }
});

As a shortcut, the Meteor.promise library (https://atmospherejs.com/deanius/promise) can get you a Promise for a method call with merely

Meteor.promise("methodName", args);

Pubsub is flexible, but reactivity goes beyond that - give this a try and let me know!