emberjs - sorting data retrieved from Firebase - sorting

Question

I've spent the last three days trying to figure this out and i hope someone from here could help.
Note regarding setup: I'm working off Ember-Cli therefore my Ember version 1.13.7 and Ember-Data 1.13.8
To learn more about how emberJS works i decided to create a simple blog system that i will use on my own website. The data is loaded from a Firebase database using the Emberfire plugin.
Help: I cannot sort the data i retrieve into a descending order. For example, if i have 5 posts created on Monday, Tues, Wednesday, Thursday and Friday. Each with a unique timestamp in numerical order.
When i retrieve data it shows in this order:
1st ever post (oldest)
2nd ever post
3rd ever post
4th ever post
5th ever post (newest)
i want to reverse the order so my latest blog post appears on top.
I am retrieving data with the following code:
return this.store.find('post');
I can't work out how to use: sortBy which is from Ember itself or the orderBy() which is from firebase/emberfire?
I understand it needs to be inside a controller which will modify the data from the model before presenting it in the view. But can anyone help?
heres some more code:
Attempt at a controller - it doesn't work:
import Ember from 'ember';
export default Ember.ArrayController.extend({
sortedModel : function(){
return this.get('model').sortBy();
}.property('#each')
});
View Template:
{{#each sortedModel as |post|}}
{{#blog-post post=post}}{{/blog-post}}
{{/each}}
{{outlet}}

Answer 1

You need a property to order your posts by. Luckily, Firebase automatically provides such a property. Every item saved to Firebase is automatically given a timestamp at that moment.
In your post model, add a timestamp property like this:
//models/post
export default DS.Model.extend({
//
timestamp: DS.attr('number')
//
});
Now in your controller you can sort by it. You don't need the #each helper because sortBy already works on arrays.
//controllers/posts
import Ember from 'ember';
export default Ember.ArrayController.extend({
sortedModel : function(){
return this.get('model').sortBy('timestamps').reverse();
}
});
I think that should work, but let me know in the comments if you have any trouble!

Answer 2

Since you said your post array is already ordered but the wrong way.
You could use Array.prototype.reverse();
export default Ember.ArrayController.extend // Array and object c are deprecated.
export default Ember.Controller.extend({
sortedModel : function() {
return this.get('model').reverse();
}).property('model')
NB: If this does not work for you (your problem is bigger, but not explained here). I think you should handle the pagination logics in backend.
Instead of
this.store.find('post');
you should be using
this.store.find('post', { page: variable });