ember-changeset-validations

controllers.application\.js

import Controller from '@ember/controller';
import { action } from '@ember/object';
import {
  validatePresence,
  validateLength,
} from 'ember-changeset-validations/validators';
import lookupValidator from 'ember-changeset-validations';
import Changeset from 'ember-changeset';

const Validations = {
  name: [
    validatePresence(true),
    validateLength({ min: 4 })
  ]
};

export default class ApplicationController extends Controller {
  appName = 'Ember Twiddle';
  model = { name: 'a' };

  @action validate() {
    this.changeset.validate();
  }

  constructor() {
    super();
                 
    this.changeset = new Changeset({ name: 'a' }, lookupValidator(Validations), Validations);
  }
}

templates.application\.hbs

<input
  value={{changeset.name}}
  {{on "input" (action (mut changeset.name) value="target.value")}}
/>
<button {{on "click" this.validate}}>validate</button>
Is valid? {{changeset.isValid}}

twiddle\.json

{
  "version": "0.17.0",
  "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/3.3.1/jquery.js",
    "ember": "3.17.0",
    "ember-template-compiler": "3.17.0",
    "ember-testing": "3.17.0"
  },
  "addons": {
    "@glimmer/component": "1.0.0",
    "ember-changeset-validations": "3.3.1"
  }
}