FormErrorResponse for handling AJAX submitted forms

gistfile1.php

<?php

    protected function getFormErrors(Form $form) {
        $errors = array();

        $children = $form->all();
        if (count($children)) {
            foreach ($children as $child) {
                if (!$child->isValid()) {
                    $errors[$child->getName()] = $this->getFormErrors($child);
                }
            }
        } else {
            foreach ($form->getErrors() as $key => $error) {
                $errors[] = $error->getMessage();
            }
        }

        return $errors;
    }