Submit array of tag names and convert to entities - forms

Question

I want to do such a trick: submit tag names as an array and then convert them to entities. Submitted data:
{"title":"Title","description":"Desc", "tags": ["first", "second"]}
Form:
class ImageType extends AbstractType
{
/**
* {#inheritdoc}
*/
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder
->add('title')
->add('description')
->add('imageFile')
->add('tags', CollectionType::class, [
'entry_type' => ImageTagType::class,
'allow_add' => true,
'allow_delete' => true,
'by_reference' => false,
]);
}
/**
* {#inheritdoc}
*/
public function configureOptions(OptionsResolver $resolver)
{
$resolver->setDefaults([
'data_class' => Image::class,
'csrf_protection' => false,
]);
}
/**
* {#inheritdoc}
*/
public function getBlockPrefix()
{
return 'appbundle_image';
}
}
Form for image tag:
class ImageTagType extends AbstractType
{
/**
* {#inheritdoc}
*/
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder->add('name');
}
/**
* {#inheritdoc}
*/
public function configureOptions(OptionsResolver $resolver)
{
$resolver->setDefaults(array(
'data_class' => 'AppBundle\Entity\ImageTag'
));
}
/**
* {#inheritdoc}
*/
public function getBlockPrefix()
{
return 'appbundle_imagetag';
}
}
The entities are connected with many-to-many. One image can have many tags and one tag can have many images. I am building an API and want to simplify tags submission. What should I do?

Answer 1

Use DataTransformer. Example:
....
$builder->get('YOUR_FILED')
->addModelTransformer(new CallbackTransformer(
function ($array) {
// your implementation here
},
function ($array) {
if (!$array) {
return;
}
return new ArrayCollection(array_map(function ($data) {
return $this->someRepository->findOneBy(['FIELD' => $data]);
}, $array));
}
));
....