[Symfony 2.8] Form data transformers always occurred before validators

[zacharyzh]

why cannot customize about this.

[xabbuh]

What is your use case for validating anything else than your model data?

[zacharyzh]

I want validate all 'categories' before transform them to 'Category' objects (Product entity has a property named 'categories').

// each value is a category id
$builder->add('categories', CollectionType::class, array(
    'allow_add' => true,
    'entry_type' => TextType::class,
    'constraints' => array(
        ...
        new CategoriesConstraints(),
    ),
));

$builder->get('categories')->addModelTransformer(new ProductCategoriesTransformer());

[xabbuh]

That does not answer my question. Why do you need to do that before the data is transformed?

[HeahDude]

You should use your Category model to validate the values by cascade when validating the owner.

[HeahDude]

This works:

class Product
{
    // ...
    /**
     * @Assert\Valid
     */
    private $categories;
// ...

[zacharyzh]

@HeahDude

But I don't know how many category ids were entered (5 ids were entered and only 1 was valid).

[zacharyzh]

@xabbuh

I want to know how many ids were entered and how many of them were invalid. it's must be done before the data transformation

[HeahDude]

You can already put that kind of logic in a POST_SUBMIT event. You can then loop through forms and use $form->addError(new FormError(...)) on the field you want to map the error to.

[HeahDude]

If you want to it before the transformation use SUBMIT event.

[zacharyzh]

I just found this on stack overflow. it's resolved my problem. but I still think it's better to be done by validators.

http://stackoverflow.com/questions/19754436/how-to-customize-datatransformer-error-message-in-symfony

[zacharyzh]

@HeahDude

thanks :)
But form event is hard to maintains.