fetch

controllers.application\.js

import Controller from '@ember/controller';
import { get, set } from "@ember/object"

export default Controller.extend({
// 	url: 'https://604630b1f0c6dc00177b180b.mockapi.io/api/v1/posts',
  
//   async init() {
// 		this._super(...arguments);
  
//   	const posts = await this.fetchPosts(this.url);
//     set(this, 'posts', posts);
// 	},
  
// 	async fetchPosts(url) {
//   	try {
//   		const response = await fetch(url);
//   		return await response.json();
//     } catch (e) {
//      console.log(e); 
//     }
//   }

});

routes.application\.js

import Route from '@ember/routing/route';

export default Route.extend({
  url: 'https://604630b1f0c6dc00177b180b.mockapi.io/api/v1/post',
 
  async model() {
    return await this.fetchPosts(this.url);
  },
  
	async fetchPosts(url) {
  	try {
  		const response = await fetch(url);
      if (response.status !== 'ok') {
      	throw new Error(response);
      }
  		const json  = await response.json();
       return json.posts;
    } catch (e) {
     console.log(`ERROR:`, e); 
    }
  }
});

templates.application\.hbs

<h1>Posts</h1>

{{#each model as |post|}}
	<div>
  	{{post.title}}
  </div>
{{/each}}

{{outlet}}

twiddle\.json

{
  "version": "0.17.1",
  "EmberENV": {
    "FEATURES": {},
    "_TEMPLATE_ONLY_GLIMMER_COMPONENTS": false,
    "_APPLICATION_TEMPLATE_WRAPPER": true,
    "_JQUERY_INTEGRATION": true
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.js",
    "ember": "2.18.2",
    "ember-template-compiler": "2.18.2",
    "ember-testing": "2.18.2"
  },
  "addons": {
    "@glimmer/component": "1.0.0",
    "ember-data": "2.18.5"
  }
}