find-by-model

controllers.application.js

import Ember from 'ember';
const { inject: {service} } = Ember;

export default Ember.Controller.extend({
  store: service(),
  appName: 'Ember Twiddle',
  init() {
    this._super(...arguments);
    
    let store = this.get('store');
    store.pushPayload(  {
    "data": [
      {
        "attributes": {
          "label": "Thingy 1"
        },
        "id": "1",
        "relationships": {
          "whatsits": {
            "data": [
              {
                "id": "2",
                "type": "whatsits"
              }
            ]
          }
        },
        "type": "thingys"
      }
    ],
    "included": [
      {
        "attributes": {
          "label": "Whatsit 2"
        },
        "id": "2",
        "relationships": {
          "thingy": {
            "data": {
              "id": "1",
              "type": "thingys"
            }
          }
        },
        "type": "whatsits"
      }
    ]
  });
    this.set('thingys', store.peekAll('thingy'));
    this.set('whatsits', store.peekAll('whatsit'));
    
    this.set('whatsit', this.get('thingys').findBy('whatsit.id', this.get('whatsits')[0].get('id')));
  }
});

models.thingy.js

import Ember from "ember";
import Model from "ember-data/model";
import attr from "ember-data/attr";
import { belongsTo, hasMany } from "ember-data/relationships";

export default Model.extend({
  whatsit: belongsTo('whatsit'),
  whatsit_id: Ember.computed.alias('whatsit.id'),
  label: attr('string')
});

models.whatsit.js

import Model from "ember-data/model";
import attr from "ember-data/attr";
import { belongsTo, hasMany } from "ember-data/relationships";

export default Model.extend({
  label: attr('string'),
  thingy: belongsTo('thingy')
});

templates.application.hbs

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

{{#each thingys as |thingy|}}
	{{thingy.label}} {{thingy.whatsit_id}}<br>
{{/each}}
<br>
{{#each whatsits as |whatsit|}}
	{{whatsit.label}}<br>
	{{#with (find-by 'whatsit' whatsit thingys) as |found|}}
  	Found by entity: {{found.label}}<br>
  {{/with}}
	{{#with (find-by 'whatsit.id' whatsit.id thingys) as |found|}}
  	Found by ID: {{found.label}}<br>
  {{/with}}
	{{#with (find-by 'whatsit_id' whatsit.id thingys) as |found|}}
  	Found by aliased ID: {{found.label}}<br>
  {{/with}}
{{/each}}
{{whatsit.label}}

<br>
{{outlet}}
<br>
<br>

twiddle.json

{
  "version": "0.13.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.16.2",
    "ember-template-compiler": "2.16.2",
    "ember-testing": "2.16.2"
  },
  "addons": {
    "ember-data": "2.16.3",
    "ember-composable-helpers": "2.1.0"
  }
}