How to use JMSSerializer with symfony 4.2 - symfony

Question

i am building an Api with symfony 4.2 and want to use jms-serializer to serialize my data in Json format, after installing it with
composer require jms/serializer-bundle
and when i try to use it this way :
``` demands = $demandRepo->findAll();
return $this->container->get('serializer')->serialize($demands,'json');```
it gives me this errur :
Service "serializer" not found, the container inside "App\Controller\DemandController" is a smaller service locator that only knows about the "doctrine", "http_kernel", "parameter_bag", "request_stack", "router" and "session" services. Try using dependency injection instead.

Answer 1

Finally i found the answer using the Symfony serializer
it's very easy:
first : istall symfony serialzer using the command:
composer require symfony/serializer
second : using the serializerInterface:
.....//
use Symfony\Component\Serializer\SerializerInterface;
use Symfony\Component\HttpFoundation\JsonResponse;
// .....
.... //
/**
* #Route("/demand", name="demand")
*/
public function index(SerializerInterface $serializer)
{
$demands = $this->getDoctrine()
->getRepository(Demand::class)
->findAll();
if($demands){
return new JsonResponse(
$serializer->serialize($demands, 'json'),
200,
[],
true
);
}else{
return '["message":"ooooops"]';
}
}
//......
and with it, i don't find any problems with dependencies or DateTime or other problems ;)

Answer 2

As I said in my comment, you could use the default serializer of Symfony and use it injecting it by the constructor.
//...
use Symfony\Component\Serializer\SerializerInterface;
//...
class whatever
{
private $serializer;
public function __constructor(SerializerInterface $serialzer)
{
$this->serializer = $serializer;
}
public function exampleFunction()
{
//...
$data = $this->serializer->serialize($demands, "json");
//...
}
}

Answer 3

Let's say that you have an entity called Foo.php that has id, name and description
And you would like to return only id, and name when consuming a particular API such as foo/summary/ in another situation need to return description as well foo/details
here's serializer is really helpful.
use JMS\Serializer\Annotation as Serializer;
/*
* #Serializer\ExclusionPolicy("all")
*/
class Foo {
/**
* #Serializer\Groups({"summary", "details"})
* #Serializer\Expose()
*/
private $id;
/**
* #Serializer\Groups({"summary"})
* #Serializer\Expose()
*/
private $title;
/**
* #Serializer\Groups({"details"})
* #Serializer\Expose()
*/
private $description;
}
let's use serializer to get data depends on the group
class FooController {
public function summary(Foo $foo, SerializerInterface $serialzer)
{
$context = SerializationContext::create()->setGroups('summary');
$data = $serialzer->serialize($foo, json, $context);
return new JsonResponse($data);
}
public function details(Foo $foo, SerializerInterface $serialzer)
{
$context = SerializationContext::create()->setGroups('details');
$data = $serialzer->serialize($foo, json, $context);
return new JsonResponse($data);
}
}