A very basic Drupal 8 AJAX repsonse

ajax_response.md

router.yml :

simple_twitter.ajax_controller_get_tweets:
  path: '_simple_twitter/tweets/{name}/{number}'
  defaults:
    _controller: '\Drupal\simple_twitter\Controller\AjaxController::getTweetsForUserAction'
    _title: 'getTweetsForUser'
  requirements:
    _permission: 'access content'

AjaxController.php :

  public function getTweetsForUserAction($name, $number = 2){
  // some service stuff that fills $results..
    $results = $this->requestTwitterAndCache($params, $url, $cid);
    return new JsonResponse($results);
    }