POST request on many-to-many association - symfony

Question

I have two entities with a many-to-many association:
class User extends BaseUser
and
class Calendar
{
/**
* #var integer
*
* #ORM\Column(name="id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #var string
*
* #ORM\Column(name="name", type="text")
*/
private $name;
/**
* #var string
*
* #ORM\Column(name="view", type="text")
* #Assert\Choice(choices = {"work week", "week", "month", "year"}, message = "Choose a valid view.")
*/
private $view;
/**
* #ManyToMany(targetEntity="AppBundle\Entity\User")
* #JoinTable(name="calendars_publishers",
* joinColumns={#JoinColumn(name="calendar_id", referencedColumnName="id")},
* inverseJoinColumns={#JoinColumn(name="publisher_id", referencedColumnName="id", unique=true)}
* )
*/
private $publishers;
public function __construct()
{
$this->publishers = new \Doctrine\Common\Collections\ArrayCollection();
}
/**
* Add publishers
*
* #param \AppBundle\Entity\User $publishers
* #return Calendar
*/
public function addPublisher(\AppBundle\Entity\User $publishers)
{
$this->publishers[] = $publishers;
return $this;
}
/**
* Remove publishers
*
* #param \AppBundle\Entity\User $publishers
*/
public function removePublisher(\AppBundle\Entity\User $publishers)
{
$this->publishers->removeElement($publishers);
}
}
And when I do a POST request on my REST API (http://localhost:8000/calendars) with the body:
{
"name": "My calendar",
"view": "week",
"publishers": [
"/users/1",
"/users/2"
]
}
I have the response:
{
"#context": "/contexts/Calendar",
"#id": "/calendars/3",
"#type": "Calendar",
"name": "My calendar",
"view": "week",
"publishers": []
}
So, as you see, my object is recorded well, but I cannot put some users in publishers. Do you have an idea?
I use the bundles:
DunglasApiBundle
NelmioApiDocBundle
NelmioCorsBundle
FOSHttpCacheBundle
FOSUserBundle
LexikJWTAuthenticationBundle
with api-platform.

Answer 1

You should add addPublisher(User $publisher) and removePublisher(User $publisher) methods.
API Platform internally uses the Symfony PropertyAccess component, and this component requires such methods to be able to access to the private property.

Answer 2

It sounds like you should specify fetch="EAGER" in the relationship so that it always gets the related objects.
see http://doctrine-orm.readthedocs.org/projects/doctrine-orm/en/latest/reference/annotations-reference.html#manytoone
(and also the next paragraph)
and some good info here: http://www.uvd.co.uk/blog/some-doctrine-2-best-practices/