how to return json encoded form errors in symfony

Question

I want to create a webservice to which I submit a form, and in case of errors, returns a JSON encoded list that tells me which field is wrong.

currently I only get a

Answer 1

By reading other people's answers I ended up improving it to my needs. I use it in Symfony 3.4.

To be used in a controller like this:

$formErrors = FormUtils::getErrorMessages($form);

return new JsonResponse([
    'formErrors' => $formErrors,
]);

With this code in a separate Utils class

getName();
        $errors = [];

        /** @var FormError $formError */
        foreach ($form->getErrors(true, true) as $formError) {
            $name = '';
            $thisField = $formError->getOrigin()->getName();
            $origin = $formError->getOrigin();
            while ($origin = $origin->getParent()) {
                if ($formName !== $origin->getName()) {
                    $name = $origin->getName() . '_' . $name;
                }
            }
            $fieldName = $formName . '_' . $name . $thisField;
            /**
             * One field can have multiple errors
             */
            if (!in_array($fieldName, $errors)) {
                $errors[$fieldName] = [];
            }
            $errors[$fieldName][] = $formError->getMessage();
        }

        return $errors;
    }
}