Symfony2 and ParamConverter(s) - symfony

Question

Accessing my route /message/new i'm going to show a form for sending a new message to one or more customers. Form model has (among others) a collection of Customer entities:
class MyFormModel
{
/**
* #var ArrayCollection
*/
public $customers;
}
I'd like to implement automatic customers selection using customers GET parameters, like this:
message/new?customers=2,55,543
This is working now by simply splitting on , and do a query for getting customers:
public function newAction(Request $request)
{
$formModel = new MyFormModel();
// GET "customers" parameter
$customersIds = explode($request->get('customers'), ',');
// If something was found in "customers" parameter then get entities
if(!empty($customersIds)) :
$repo = $this->getDoctrine()->getRepository('AcmeHelloBundle:Customer');
$found = $repo->findAllByIdsArray($customersIds);
// Assign found Customer entities
$formModel->customers = $found;
endif;
// Go on showing the form
}
How can i do the same using Symfony 2 converters? Like:
public function newAction(Request $request, $selectedCustomers)
{
}

Answer 1

Answer to my self: there is not such thing to make you life easy. I've coded a quick and dirty (and possibly buggy) solution i'd like to share, waiting for a best one.
EDIT WARNING: this is not going to work with two parameter converters with the same class.
Url example
/mesages/new?customers=2543,3321,445
Annotations:
/**
* #Route("/new")
* #Method("GET|POST")
* #ParamConverter("customers",
* class="Doctrine\Common\Collections\ArrayCollection", options={
* "finder" = "getFindAllWithMobileByUserQueryBuilder",
* "entity" = "Acme\HelloBundle\Entity\Customer",
* "field" = "id",
* "delimiter" = ",",
* }
* )
*/
public function newAction(Request $request, ArrayCollection $customers = null)
{
}
Option delimiter is used to split GET parameter while id is used for adding a WHERE id IN... clause. There are both optional.
Option class is only used as a "signature" to tell that converter should support it. entity has to be a FQCN of a Doctrine entity while finder is a repository method to be invoked and should return a query builder (default one provided).
Converter
class ArrayCollectionConverter implements ParamConverterInterface
{
/**
* #var \Symfony\Component\DependencyInjection\ContainerInterface
*/
protected $container;
public function __construct(ContainerInterface $container)
{
$this->container = $container;
}
function apply(Request $request, ConfigurationInterface $configuration)
{
$name = $configuration->getName();
$options = $this->getOptions($configuration);
// Se request attribute to an empty collection (as default)
$request->attributes->set($name, new ArrayCollection());
// If request parameter is missing or empty then return
if(is_null($val = $request->get($name)) || strlen(trim($val)) === 0)
return;
// If splitted values is an empty array then return
if(!($items = preg_split('/\s*'.$options['delimiter'].'\s*/', $val,
0, PREG_SPLIT_NO_EMPTY))) return;
// Get the repository and logged user
$repo = $this->getEntityManager()->getRepository($options['entity']);
$user = $this->getSecurityContext->getToken()->getUser();
if(!$finder = $options['finder']) :
// Create a new default query builder with WHERE user_id clause
$builder = $repo->createQueryBuilder('e');
$builder->andWhere($builder->expr()->eq("e.user", $user->getId()));
else :
// Call finder method on repository
$builder = $repo->$finder($user);
endif;
// Edit the builder and add WHERE IN $items clause
$alias = $builder->getRootAlias() . "." . $options['field'];
$wherein = $builder->expr()->in($alias, $items);
$result = $builder->andwhere($wherein)->getQuery()->getResult();
// Set request attribute and we're done
$request->attributes->set($name, new ArrayCollection($result));
}
public function supports(ConfigurationInterface $configuration)
{
$class = $configuration->getClass();
// Check if class is ArrayCollection from Doctrine
if('Doctrine\Common\Collections\ArrayCollection' !== $class)
return false;
$options = $this->getOptions($configuration);
$manager = $this->getEntityManager();
// Check if $options['entity'] is actually a Dcontrine one
try
{
$manager->getClassMetadata($options['entity']);
return true;
}
catch(\Doctrine\ORM\Mapping\MappingException $e)
{
return false;
}
}
protected function getOptions(ConfigurationInterface $configuration)
{
return array_replace(
array(
'entity' => null,
'finder' => null,
'field' => 'id',
'delimiter' => ','
),
$configuration->getOptions()
);
}
/**
* #return \Doctrine\ORM\EntityManager
*/
protected function getEntityManager()
{
return $this->container->get('doctrine.orm.default_entity_manager');
}
/**
* #return \Symfony\Component\Security\Core\SecurityContext
*/
protected function getSecurityContext()
{
return $this->container->get('security.context');
}
}
Service definition
arraycollection_converter:
class: Acme\HelloBundle\Request\ArrayCollectionConverter
arguments: ['#service_container']
tags:
- { name: request.param_converter}

Answer 2

It's late, but according to latest documentation about #ParamConverter, you can achieve it follow way:
* #ParamConverter("users", class="AcmeBlogBundle:User", options={
* "repository_method" = "findUsersByIds"
* })
you just need make sure that repository method can handle comma (,) separated values