Using the result of a promise in Ember.RSVP.hash - ember.js

Question

I've been pulling out my hair with this for a few hours now so I thought I'd just ask :)
In the model hook of my route, I'm grabbing the account ID from the session store. I'm also returning an Ember hash of layouts using a (presently) hard-coded ID:
model: function() {
var accountId = this.get('session.currentUser').then(function(user) {
return user;
}).then(function(user) {
return user.get('account');
}).then(function(account) {
var accountId = parseInt(account.get('id'));
console.log(accountId); // outputs 2
return accountId;
});
return Ember.RSVP.hash({
layouts: this.store.query('layout', { account_id: 2 })
});
},
/* {{log layouts}} in the template returns the correct list of layouts */
However, when I try and use the value of the first promise in the hash, as follows:
return Ember.RSVP.hash({
layouts: this.store.query('layout', { account_id: accountId })
});
I get the following error:
You must pass a resolver function as the first argument to the promise constructor
TypeError: You must pass a resolver function as the first argument to the promise constructor
I can almost understand this, as perhaps the accountID promise isn't resolved before the hash function is called.
But then I tried:
var _this = this;
var accountId = this.get('session.currentUser').then(function(user) {
return user;
}).then(function(user) {
return user.get('account');
}).then(function(account) {
var accountId = parseInt(account.get('id'));
console.log(accountId); // outputs 2
return accountId;
}).then(function(accountId) {
console.log(accountId); // outputs 2
return Ember.RSVP.hash({
layouts: _this.store.query('layout', { account_id: accountId })
});
});
This does not give any errors, but {{log layouts}} in the template returns 'undefined'.
Can anyone help, please?

Answer 1

Instead of returning the hash at the end, structure your promise the other way around:
var _this = this;
return Ember.RSVP.hash({
layouts: this.get('session.currentUser').then(function(user) {
return user;
}).then(function(user) {
return user.get('account');
}).then(function(account) {
return parseInt(account.get('id'), 10);
}).then(function(accountId) {
return _this.store.query('layout', { account_id: accountId });
})
});