OneToOne relationship in Doctrine2 ORM and Symfony - php

Question

I have two entity called PictureTag and Tag, here's the relationship:
/**
* #ORM\Entity
* #ORM\Table(name="picture_tag")
* #ORM\HasLifecycleCallbacks()
*/
class PictureTag
{
/**
* #var integer $id
*
* #ORM\Column(name="id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
*
* #ORM\OneToOne(targetEntity="App\MainBundle\Entity\Tag", inversedBy="id")
* #ORM\JoinColumn(name="tag_id", referencedColumnName="id", nullable=false)
*/
private $tag;
}
/**
* #ORM\Entity
* #ORM\Table(name="tag")
* #ORM\HasLifecycleCallbacks()
*/
class Tag
{
/**
* #var integer $id
*
* #ORM\Column(name="id", type="integer")
* #ORM\ManyToOne(targetEntity="App\MainBundle\Entity\PictureTag", inversedBy="tag")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #var string
* #ORM\Column(name="tag", type="string", nullable=true)
*/
private $tag;
}
Basically I wanted the tag table to contain all the unique tags, so there are no duplicate in the tag. And i wanted picturetag to have a joincolumn that points to the id of the tag. So here's my code in the controller:
foreach ($image->tags as $tag) {
$existingTag = $em->getRepository('AppMainBundle:InstagramTag')->findOneByTag($tag);
$instaPictureTag = new PictureTag();
if ($existingTag) {
$instaPictureTag->setTag($existingTag);
} else {
$instagramTag = new Tag();
$instagramTag->setTag($tag);
$em->persist($instagramTag);
$instaPictureTag->setTag($instagramTag);
}
$instaPictureTag->setPicture($instaShopPicture);
$em->persist($instaPictureTag);
}
So the relationship is basically:
One picture is going to have many tags. And one tag will belong to many pictures.
Picture tag here is the intermediary table.
Basically I am doing a check if the tag already exists in the tag table, if it is then I set the picturetag to be associated with this tag, if not then create one. However doing so generates the following error:
Fatal error: Call to a member function setValue() on a non-object in /Users/MyName/Sites/App/vendor/doctrine/orm/lib/Doctrine/ORM/UnitOfWork.php on line 2625
Any idea why this is?

Answer 1

As I understand, you want implement OneToMany bidirectional relation between PictureTag and Tag.
Please try:
/**
* #ORM\Entity
* #ORM\Table(name="picture_tag")
* #ORM\HasLifecycleCallbacks()
*/
class PictureTag
{
/**
* #ORM\Column(name="id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #ORM\ManyToOne(targetEntity="DynamicSolutions\Bundle\ProsAndConsBundle\Entity\Tag", inversedBy="pictureTags")
* #ORM\JoinColumn(name="tag_id", referencedColumnName="id", nullable=false)
*/
private $tag;
}
/**
* #ORM\Entity
* #ORM\Table(name="tag")
* #ORM\HasLifecycleCallbacks()
*/
class Tag
{
/**
* #ORM\Column(name="id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #ORM\OneToMany(targetEntity="PictureTag", mappedBy="tag")
*/
private $pictureTags;
/**
* #var string
* #ORM\Column(name="tag", type="string", nullable=true)
*/
private $tag;
}