Using Subscribing Handler Interface when Serialize te modify parameters in symfony - symfony

Question

I have a REST API and have an Entity Userwith field called Avatar, in DB I save name XXXX.jpg but when I return I want to add a url in this field Avatar, for example www.mylink.com/XXXX.jpg.
I'm trying with a service implements SubscribingHandlerInterfacebut I don't know how I can use it.
I have this method in this service:
class UrlManager implements SubscribingHandlerInterface
{
public static function getSubscribingMethods()
{
return array(
array(
'direction' => GraphNavigator::DIRECTION_SERIALIZATION,
'format' => 'json',
'type' => 'AppBundle/Entity/User',
'method' => 'serializeUrlAvatar',
),
);
}
public function serializeUrlAvatar(User $user)
{
$url = 'www.mylink.com';
return array(
"avatar" => $url . $user->getAvatar()
);
}
}
but how can I call this service to modify url when I serialize.
Now I do this:
$_format = 'json';
$json = $this->get('jms_serializer')->serialize($user, $_format);
return new Response($json, 200, ['Content-Type' => 'application/' . $_format]);
In service.yml:
app.url_converter_service:
class: AppBundle\Service\UrlManager
tags:
- { name: jms_serializer.subscribing_handler }
Update
In my controller I call this function like this:
$result = $this->get('app.url_converter_service')->serializeUrlAvatar($user);
$json = $this->get('jms_serializer')->serialize($result, $_format);
return new Response($json, 200, ['Content-Type' => 'application/' . $_format]);
So my question is, exists a way to remove the first line and serialize correctly (add the url) when I serialize?

Answer 1

Have you registered your service like this?
# app/config/services.yml
avatar_url_handler:
class: YourBundle\Serializer\Handler\AvatarUrlHandler
tags:
- { name: jms_serializer.subscribing_handler }

Answer 2

I found a solution. I create a service which implements EventSubscriberInterface like this:
class UserSerializeHandler implements EventSubscriberInterface
{
private $user_uploads;
public function __construct($user_uploads){
$this->user_uploads = $user_uploads;
}
public static function getSubscribedEvents()
{
return array(
array(
'event' => 'serializer.pre_serialize',
'class' => User::class,
'method' => 'onPreSerializeUser'
));
}
public function onPreSerializeUser(PreSerializeEvent $event)
{
/** #var User $user */
$user = $event->getObject();
$avatar = $user->getAvatar();
$user->setAvatar($this->user_uploads . "/" . $avatar);
}
}
In service.yml:
app.serializer_user_service:
class: AppBundle\Service\UserSerializeHandler
arguments: ['%user_uploads%']
tags:
- { name: jms_serializer.event_subscriber }
I have user_uploads in parameters.yml like this:
user_uploads: 'https://myUrl.com'
And in any Controller that I serialize a User, I add the url in the Avatar paramter.
$json = $this->get('jms_serializer')->serialize($user, $_format);
return new Response($json, 200, ['Content-Type' => 'application/' . $_format]);