CP based QP

application.controller.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName:'Ember Twiddle'
});

application.template.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
<br>
<br>

index.controller.js

import Ember from 'ember';

const today = new Date().toLocaleDateString().split('/').join('-');

export default Ember.Controller.extend({
  today,
  queryParams: ['date'],
  
  // date can be used in query-params helper
  date: today,
  
  // dateParam is the middle transform layer, 
  // typically you don't need use it directly,
  // but if you want to change `date` in code,
  // you should set `dateParam` instead of `date` like `setDate()` action did
  dateParam: Ember.computed('model.date', {
    get(k) {
      let v = this.get('model.date');
      this.set('date', v ? v.split('/').join('-') : null);
      return v;
    },
    set(k, v) {
      this.set('date', v ? v.split('/').join('-') : null);
      return v;
    }
  }),
  
  actions: {
    setDate(date) {
      this.set('dateParam', date);
    }
  }
});

index.route.js

import Ember from 'ember';

export default Ember.Route.extend({
  queryParams: {
    date: { refreshModel: true }
  },
  
  model(params) {
    const date = params.date ? params.date.split('-').join('/') : null;
    
    /**
     * you can enable this to simulate the default value from API
     *
    const date = params.date ? params.date.split('-').join('/') : '2015/11/30';
     */
    return { date }
  }
});

index.template.hbs

{{link-to "Today" "index" (query-params date=today)}}

<hr>

{{link-to "Another Day" "index" (query-params date="2015/01/01")}}

<hr>

<strong>Date: {{date}}</strong>

<hr>

<strong>DateParam: {{dateParam}}</strong>

<hr>

<strong>model.date: {{model.date}}</strong>

<hr>

<button type="button" {{action 'setDate' '2012/12/31'}}>Set Date</button>

twiddle.json

{
  "version": "0.4.16",
  "EmberENV": {
    "FEATURES": {}
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.2.0/ember.debug.js",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/2.2.0/ember-data.js",
    "ember-template-compiler": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.2.0/ember-template-compiler.js"
  }
}