Unique Form Element IDs

components.form-group.js

import Ember from 'ember';

const {
  get,
  computed
} = Ember;

export default Ember.Component.extend({
	id: null,
  
  inputId: computed('id', function() {
    // Fetch this component's ID, whether it be custom or Ember generated
    const containerId = get(this, 'id') || get(this, 'elementId');
    
  	return `${containerId}-input`;  
  })
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend();

templates.application.hbs

<h1>Unique Form Element IDs</h1>

{{#form-group as |inputId|}}
	{{input value=myValue id=inputId}}
{{/form-group}}

<p>The form input value is: {{if myValue myValue 'Empty'}}</p>

templates.components.form-group.hbs

<label for={{inputId}}>Label for <em>{{inputId}}</em>: </label>
{{yield inputId}}

twiddle.json

{
  "version": "0.10.6",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.9.0",
    "ember-data": "2.9.0",
    "ember-template-compiler": "2.9.0",
    "ember-testing": "2.9.0"
  },
  "addons": {}
}