Symfony - How to deserialize with default values? - symfony

Question

I'm starting to learn Symfony 4.
I want to deserialize datas from json data. (I'm using JMSSerializer)
This is my context :
I have a Customer entity in src/App/Entity
class Customer {
/**
*
* #ORM\Id
* #ORM\Column(type="integer")
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #ORM\Column(type="string", length=250)
* #Assert\NotBlank()
*/
private $name;
/**
* #ORM\Column(type="string", length=250)
* #Assert\NotNull
*/
private $comment;
public function __construct() {
$this->comment = "";
}
}
I have a CustomerController controller in src/App/Controller
class CustomerController extends Controller
{
/**
* #Route("/customers", name="customer_create")
* #Method({"POST"})
*/
public function createAction(Request $request)
{
$data = $request->getContent();
//Il faudrait valider les données avant de les mettre en base de données
$customer = $this->get('jms_serializer')->deserialize($data, 'App\Entity\Customer', 'json');
$em = $this->getDoctrine()->getManager();
$em->persist($customer);
$em->flush();
return new Response('', Response::HTTP_CREATED);
}
}
I post a request for creating a customer with the following JSON data:
{"name":"Customer Lambda"}
but I have the following error
NotNullConstraintViolationException
An exception occurred while executing 'INSERT INTO customers (id, name, comment) VALUES (?, ?, ?, ?)' with params [Resource id #99, "Customer Lambda", null]:
SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'comment'
cannot be null
Is it possible to set a default value (empty string) for the comment field after deserialize? I was thinking that setting it in the Customer constructor will fix the issue but it is not the case.

Answer 1

1º Why are you trying to set empty string if you have defined comment as not nullable.
2º
This:
/**
* #ORM\Column(type="string", length=250)
* #Assert\NotNull
*/
private $comment = "";
public function __construct() {
}
Instead this:
/**
* #ORM\Column(type="string", length=250)
* #Assert\NotNull
*/
private $comment;
public function __construct() {
$this->comment = "";
}