how to map violation to Symfony form manually? - symfony

Question

OrderType
$builder
->add('items', FormTypes\CollectionType::class, [
'entry_type' => OrderItemType::class,
'allow_add' => true,
'allow_delete' => true,
'by_reference' => false,
'label' => 'acme.form.order.items',
])
->add('channel', ChannelSelectType::class, [
'required' => true,
'label' => 'acme.form.order.channel',
])
OrderItemType
$builder
->add('service', ServiceSelectType::class, [
'label' => 'acme.form.order_item.service',
])
->add('product', ProductSelectType::class, [
'label' => 'acme.form.order_item.product',
])
->add('quantity', FormTypes\IntegerType::class, [
'label' => 'acme.form.order_item.quantity',
]);
How to map the error to OrderItemType product field?
the order item is valid when a product is applied to a specific channel. however we have no way to get the submited channel in OrderItemType,
because child form type is submmited before its parent. so $event->getForm()->getParent()->getData()->getChannel() is empty. the only way I have
is to validate order item in OrderType, or create a validator which is added to Order class. the problem is how can I map the error to OrderItemType product field.
$orderItems = $order->getItems();
$channel = $order->getChannel();
foreach($orderItems as $index => $orderItem) {
$product = $orderItem->getProduct();
if (!$this->isProductAvailableForChannel($channel, $product)) {
$message = sprintf('product %ss is not available for channel "%s"', $product->getName(), $channel->getName());
}
if (null !== $message) {
$this->context
->buildViolation($this->constraint->message)
->setParameter($message)
->atPath("items.children[$index].product") // this doesn't work, the error will be added to root form.
->addViolation()
;
}
}

Answer 1

You are able to get the channel on the pre submit event (Symfony\Component\Form\FormEvents::PRE_SUBMIT)
And there you can add your channel based validation for the order item
$addItems = function (FormEvent $event) {
$data = $event->getData();
$form = $event->getForm();
$options = [];
if (is_array($data) && array_key_exists('channel', $data)) {
$options['constraints'] = [
new OrderItemConstraint(['channel' => $data['channel']])
];
}
$form->add('items', FormTypes\CollectionType::class, [
'entry_type' => OrderItemType::class,
'entry_options' => $options,
'allow_add' => true,
'allow_delete' => true,
'by_reference' => false,
'label' => 'acme.form.order.items',
]);
};
$builder->addEventListener(FormEvents::PRE_SET_DATA, $addItems);
$builder->addEventListener(FormEvents::PRE_SUBMIT, $addItems);