sample-validated-input

components.validated-input.js

import Ember from 'ember';

const { computed, isPresent } = Ember;

export default Ember.Component.extend({
  errors: null,
  label: null,
  value: computed('errors', {
    get() { return null; },
    set(_,v) {
      let { label, errors } = this.getProperties('errors', 'label');
      if (v === 'invalid' && errors) {
        console.log('failed');
        errors.add(label, 'is invalid');
        return v;
      } else if (errors) {
        errors.remove(label);
        return v;
      }
    }
  }),
});

controllers.application.js

import Ember from 'ember';
import DS from 'ember-data';

const { Errors } = DS;

export default Ember.Controller.extend({
  appName: 'Validated input',
  name: '',
  init() {
    this._super(...arguments);
    this.set('errors', Errors.create());
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
{{validated-input value=name label='name' errors=errors}}
<br>
<br>

templates.components.validated-input.hbs

{{input value=value}}
{{#each errors as |error|}}
  <span>{{error.message}}</span>
{{/each}}

twiddle.json

{
  "version": "0.10.4",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.7.0",
    "ember-data": "2.7.0",
    "ember-template-compiler": "2.7.0"
  },
  "addons": {}
}