Symfony3 Edit Entity : Error Missing value for primary key - doctrine

Question

I try to create a tree structure for a catalog of products.
A catalog can have multiple levels and levels can contain multiple products.
I manage to save my structure in database but when I want to edit it, I have this error :
Error : Missing value for primary key catalogCode on AppBundle\Entity\CatalogLevel
at OutOfBoundsException ::missingPrimaryKeyValue ('AppBundle\Entity\CatalogLevel', 'catalogCode')
in vendor\doctrine\common\lib\Doctrine\Common\Proxy\AbstractProxyFactory.php at line 125
when I do this in my CatalogController :
$form = $this->createForm(CatalogTreeType::class, $catalog);
But, just before that line, I verify if I get my levels correctly and it's looking like that's the case :
// Create an ArrayCollection of the current levels
$originalLevels = new ArrayCollection();
foreach ($catalog->getLevels() as $level) {
var_dump($level->getCatalogCode());
$originalLevels->add($level);
}
// returns
AppBundle\Controller\CatalogController.php:337:string 'TT-FTEST' (length=8)
AppBundle\Controller\CatalogController.php:337:string 'TT-FTEST' (length=8)
CatalogLevel entity has a composite key : levelId + catalogCode.
Considering the primary key catalogCode isn't empty, I don't understand this error...
Catalog Entity
/**
* #ORM\Table(name="catalogue")
* #ORM\Entity(repositoryClass="AppBundle\Entity\CatalogRepository")
* #UniqueEntity(fields="code", message="Catalog code already exists")
*/
class Catalog
{
/**
* #ORM\Column(name="Catalogue_Code", type="string", length=15)
* #ORM\Id
* #Assert\NotBlank()
* #Assert\Length(max=15, maxMessage="The code is too long ({{ limit }} characters max)")
*/
private $code;
/**
* #ORM\OneToMany(targetEntity="CatalogLevel", mappedBy="catalog", cascade={"persist", "remove"})
* #Assert\Valid
*/
private $levels;
/**
* Constructor
*/
public function __construct()
{
$this->levels = new ArrayCollection();
}
/**
* Get levels
*
* #return ArrayCollection
*/
public function getLevels()
{
return $this->levels;
}
/**
* Add level
*
* #param \AppBundle\Entity\CatalogLevel $level
*
* #return Catalog
*/
public function addLevel(\AppBundle\Entity\CatalogLevel $level)
{
$level->setCatalogCode($this->getCode());
$level->setCatalog($this);
if (!$this->getLevels()->contains($level)) {
$this->levels->add($level);
}
return $this;
}
/**
* Remove level
*
* #param \AppBundle\Entity\CatalogLevel $level
*/
public function removeLevel(\AppBundle\Entity\CatalogLevel $level)
{
$this->levels->removeElement($level);
}
}
CatalogLevel Entity
/**
* #ORM\Table(name="catalogue_niveau")
* #ORM\Entity(repositoryClass="AppBundle\Entity\CatalogLevelRepository")
*/
class CatalogLevel
{
/**
* #ORM\Column(name="Niveau_ID", type="string", length=15)
* #ORM\Id
*/
private $id;
/**
* #ORM\Column(name="Catalogue_Code", type="string", length=15)
* #ORM\Id
*/
private $catalogCode;
/**
* #ORM\ManyToOne(targetEntity="Catalog", inversedBy="levels")
* #ORM\JoinColumn(name="Catalogue_Code", referencedColumnName="Catalogue_Code")
*/
private $catalog;
/**
* Set id
*
* #param string $id
*
* #return CatalogLevel
*/
public function setId($id)
{
$this->id = $id;
return $this;
}
/**
* Get id
*
* #return string
*/
public function getId()
{
return $this->id;
}
/**
* Set catalogCode
*
* #param string $catalogCode
*
* #return CatalogLevel
*/
public function setCatalogCode($catalogCode)
{
$this->catalogCode = $catalogCode;
return $this;
}
/**
* Get catalogCode
*
* #return string
*/
public function getCatalogCode()
{
return $this->catalogCode;
}
}
I would like to remind you that this error occured on the editAction (it works very well on the addAction) when I display the pre-filled form.
Thanks for your help !

Answer 1

I think that is because you haven't autoincrement id in entity CatalogLevel. Try add to id this code:
#ORM\GeneratedValue(strategy="AUTO")

Answer 2

You have some problems in the way you've created you Entities. You should use auto generate strategy. Also the "#ORM\Id" annotation is the unique identifier.
Also, your "JoinColumn" is incorrect. You need to refer back to the "Catalog" Entity, and it's id (identifier). There is no need for 2 "#ORM\Id" entries in the class CatalogLevel.
So make these changes:
/**
* #ORM\Table(name="catalog")
* #ORM\Entity(repositoryClass="AppBundle\Entity\CatalogRepository")
*/
class Catalog
{
/**
* #ORM\Column(name="cat_id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $cat_id;
/**
* #ORM\OneToMany(targetEntity="CatalogLevel", mappedBy="catalog", cascade={"persist", "remove"})
* #Assert\Valid
*/
private $levels;
...
/**
* #ORM\Table(name="catalog_level")
* #ORM\Entity(repositoryClass="AppBundle\Entity\CatalogLevelRepository")
*/
class CatalogLevel
{
/**
* #ORM\Column(name="cat_level_id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $cat_level_id;
/**
* #ORM\ManyToOne(targetEntity="Catalog", inversedBy="levels")
* #ORM\JoinColumn(name="local_cat_id", referencedColumnName="cat_id")
*/
private $catalog;
...