Sylius 覆盖CoreBundle/型号/产品

我正在努力覆盖这个产品，我不确定它是否是一个bug。 覆盖工作正常，但当我要在Sylius后端创建新产品时，会出现以下异常：

An exception occurred while executing 'INSERT INTO sylius_variant 
(is_master,     presentation, available_on, created_at, updated_at, deleted_at, 
 sku, price, on_hold, on_hand, available_on_demand, width, height, depth, weight,
 product_id) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)' 

with params [1, null, "2014-04-07 18:43:00", "2014-04-07 19:12:25", 
"2014-04-07 19:12:25", null, null, 10000, 0, 0, 1, null, null, null, null, null]:

SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'product_id' cannot be null

我的代码如下所示：

<?php


namespace Acme\ShopBundle\Entity;

use Doctrine\ORM\Mapping as ORM;
use Sylius\Bundle\CoreBundle\Model\Product as BaseProduct;
use Doctrine\Common\Collections\ArrayCollection;
use Sylius\Bundle\CoreBundle\Model\Variant;

/**
 * @ORM\Entity()
 * @ORM\Table(name="sylius_product")
 */
class Product extends BaseProduct
{

    public function __construct() {
        parent::__construct();
    }
}

有人知道我是否遗漏了什么吗

谢谢，

---

David

只需用以下代码替换产品模型的construct（）。之后，它将正常工作

use Doctrine\Common\Collections\ArrayCollection;

class Product extends BaseProduct
{

   public function __construct() {
      $this->availableOn = new \DateTime();
      $this->properties = new ArrayCollection();
      $this->createdAt = new \DateTime();

      $this->variants = new ArrayCollection();
      $this->options = new ArrayCollection();

      $this->setMasterVariant(new Variant());
      $this->taxons = new ArrayCollection();
      $this->variantSelectionMethod = self::VARIANT_SELECTION_CHOICE;
   }
}

use Doctrine\Common\Collections\ArrayCollection;

class Product extends BaseProduct
{

   public function __construct() {
      $this->availableOn = new \DateTime();
      $this->properties = new ArrayCollection();
      $this->createdAt = new \DateTime();

      $this->variants = new ArrayCollection();
      $this->options = new ArrayCollection();

      $this->setMasterVariant(new Variant());
      $this->taxons = new ArrayCollection();
      $this->variantSelectionMethod = self::VARIANT_SELECTION_CHOICE;
   }
}