attribute-decorator

components.my-component.js

import Ember from 'ember';
import { alias } from '@ember-decorators/object/computed';
import { attribute } from '@ember-decorators/component';

export default class extends Ember.Component {
  @attribute('data-value')
  @alias('value')
	valueAttr;
  
}

controllers.application.js

import Ember from 'ember';

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

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{my-component value="1234"}}
<br>
<br>

templates.components.my-component.hbs

<p>Value is {{@value}}</p>

twiddle.json

{
  "version": "0.15.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "3.2.0",
    "ember-template-compiler": "3.2.2",
    "ember-testing": "3.2.2"
  },
  "addons": {
    "ember-data": "3.1.1",
    "ember-decorators": "2.0.0"
  }
}