Symfony2 Entity form type with a specific query_buider - symfony-2.1

Question

Context
In my case, I've some orders with "discount vouchers" (discount). A discount can be use on under different conditions. For instance, discounts have an expired date, can be used by a limited number of customers, can be dedicated to a user, ...
Each discount can be attached to several order.
In my backoffice, I want to add to order create form a field "Discount" with a list of discount available but only right discounts.
What I made
An entity "order" with a field manyToMany
/**
* #ORM\ManyToMany(targetEntity="PATH\MyBundle\Entity\Discount", inversedBy="orders")
* #ORM\JoinTable(name="shop_discounts_orders",
* joinColumns={#ORM\JoinColumn(name="order_id", referencedColumnName="id")},
* inverseJoinColumns={#ORM\JoinColumn(name="discount_id", referencedColumnName="id")}
* )
*/
private $discounts;
An entity "discounts" with a field manyToMany
/**
* #ORM\ManyToMany(targetEntity="PATH\MyBundle\Entity\Order", mappedBy="discounts")
*/
private $orders;
A form OrderType with a field discounts
$builder->add('discounts', 'entity',
array( 'label' => 'Discount vouchers',
'required' => false,
'expanded' => true,
'class' => 'PATH\MyBundle\Entity\Discount',
'property' => 'title',
'multiple' => true,
'query_builder' => function(EntityRepository $er) use ($params) {
return $er->getQuerySelectType($params);
},
));
With this solution, I can return specific discount defined by my request in my entity repository. It's good for expired date condition for instance.
What I would like
I'd like to filter results in the checkbox list. In fact, I want limit usage of the discount to a dedicated user, limit to a list of products, or limit the number of usage... And these condition cannot be done by a simple sql request.
I try to create special Type. My idea is to have an array of entities Discount and load a choice list... After that, I create a dataTransformer but It doesn't work !
Thank's for your ideas !

Answer 1

You could use the $options from public function buildForm(FormBuilderInterface $builder, array $options) to pass your user and product for instance. With those 2 informations you could refine your list of discount (in your query)
if you do so you need to add them in the setDefaultValue
public function setDefaultOptions(OptionsResolverInterface $resolver)
{
$resolver->setDefaults(array(
'user_discount' => null,
'product_discount' => null,
));
}
and in your controller:
$form = $this->formFactory->create(new YourFormType(), $entity, array(
'user_discount' => $this->getUser(),
'product_discount' => $product,
));

Answer 2

I found a solution and explain it if someone have the same issue as me.
Create a custom Type
My custom type is inspired by Symfony\Bridge\Doctrine\Form\Type\DoctrineType
class DiscountOrderType extends AbstractType
{
// overide choiceList callback
public function setDefaultOptions(OptionsResolverInterface $resolver)
{
$choiceListCache =& $this->choiceListCache;
$type = $this;
$choiceList = function (Options $options) use (&$choiceListCache, &$time, $container) {
[[ Copy paste same as Doctrine type ]]
// Create your own choiceList class (EntityChoiceList)
if (!isset($choiceListCache[$hash])) {
$choiceListCache[$hash] = new DiscountChoiceList(
$options['em'],
$options['class'],
$options['property'],
$options['loader'],
$options['choices'],
$options['group_by']
);
// If you want add container
$choiceListCache[$hash]->setContainer($container);
}
return $choiceListCache[$hash];
};
$resolver->setDefaults(array(
'choice_list' => $choiceList,
));
}
Create a custom EntityChoiceList
My custom type is inspired by Symfony\Bridge\Doctrine\Form\ChoiceList\EntityChoiceList
class EntityChoiceList extends ObjectChoiceList
{
protected function load()
{
if ($this->entityLoader) {
$entities = $this->entityLoader->getEntities();
} else {
$entities = $this->em->getRepository($this->class)->findAll();
}
// You have access to the entities in the choice list
// Add your custom code here to manipulate the choice list
// you can do some check not properly possible with sql request (http requests on each result, ...) before add it in choice list
// you can add some custom cache rules, ...
// if you use gedmon and want apply a "join" with translate table, you can add $query->setHint(\Doctrine\ORM\Query::HINT_CUSTOM_OUTPUT_WALKER, 'Gedmo\\Translatable\\Query\\TreeWalker\\TranslationWalker'); before playing request...
// Possibilities are infinite
// FOR INSTANCE : you already want unset first entity of the result
if (isset($entities[0])) {
unset($entities[0]);
}
// END OF CUSTOM CODE
try {
// The second parameter $labels is ignored by ObjectChoiceList
// The third parameter $preferredChoices is currently not supported
parent::initialize($entities, array(), array());
} catch (StringCastException $e) {
throw new StringCastException(str_replace('argument $labelPath', 'option "property"', $e->getMessage()), null, $e);
}
$this->loaded = true;
}
Of course you can try to extend symfony class for beautyfull code ;).
Thank's to #maxwell2022 for your help !