Allowing NULL value in json with API-Platform - php

Question

I have currently this entity and I want to show my property firedDate in my JSON even is the value is null.
/**
* #ApiResource(normalizationContext={"groups"={"employee"}})
* #ApiFilter(DateFilter::class, properties={"dateProperty": DateFilter::INCLUDE_NULL_BEFORE_AND_AFTER})
* #ORM\Table(name="employee")
*/
class Employee
{
// ...
/**
* #ORM\Column(type="datetime", nullable=true)
* #Groups({"employee"})
*/
private $firedDate;
public function getFiredDate(): ?\DateTimeInterface
{
return $this->firedDate;
}
// ...
}
Currently, when the value is null, it's not shown in the response.

Answer 1

I think I found the right solution to this problem.
Set skip_null_values in false in your normalizationContext:
* #ApiResource(
* itemOperations={
* "get" = {
* //...
* }
* "put" = {
* //...
* },
* "patch" = {
* //...
* }
* },
* collectionOperations={
* "get",
* "post" = {
* //...
* }
* },
* normalizationContext={
* "skip_null_values" = false,
* "groups" = {"object:read"}
* },
* denormalizationContext={"groups" = {"object:write"}}
* )

Answer 2

Are you under PHP 7.0 or above?
In PHP 7.1 you can have nullable return types for functions, so your
public function getFiredDate(): ?\DateTime
{
return $this->firedDate;
}
With the ? before \DateTime, the function will return null as well.

Answer 3

On ApiPlatform 3 the default has changed from skip_null_values=false to skip_null_values=true.
If you don't want having to set this on each resource, and would like to have the default as it as on ApiPlatform < 3, you can simply set it on the global config:
api_platform:
defaults:
normalization_context:
skip_null_values: false
Or if you use PHP based configuration:
return static function (Symfony\Config\ApiPlatformConfig $apiConfig): void {
$apiConfig
->defaults()
->normalizationContext(['skip_null_values' => false]);
}

Answer 4

Maybe your entity is missing a getter like this one?
public function getFiredDate(): \DateTime
{
return $this->firedDate;
}

Answer 5

Just get the solution from a friend on github, here is it:
* #ApiResource(
* itemOperations={"get"},
* )
BEFORE:
{
"#context": "/contexts/Employee",
"#id": "/employees/1",
"#type": "Employee",
"id": 1,
"name": "Oliver",
"hired": "2019-10-10T00:00:00+00:00",
"experience": 0,
"salary": "1200.00",
"job": {
"#id": "/employee_jobs/1",
"#type": "EmployeeJob",
"id": 1,
"name": "Mécanicien"
}
}
AFTER:
{
"#context": "/contexts/Employee",
"#id": "/employees/1",
"#type": "Employee",
"id": 1,
"name": "Oliver",
"hired": "2019-10-10T00:00:00+00:00",
"experience": 0,
"salary": "1200.00",
"firedDate": null,
"job": {
"#id": "/employee_jobs/1",
"#type": "EmployeeJob",
"id": 1,
"name": "Mécanicien"
}
}