ManyToMany relationship with extra fields in symfony2 orm doctrine

Question

Hi i have that same question as here: Many-to-many self relation with extra fields? but i cant find an answer :/ I tried first ManyToOne and at the other site OneToMany ... but

Answer 1

I'm adding another answer since it has nothing to do with my original answer. Using the new info you posted, I'm calling the table/entity you posted "Follower". The original entity, "User".

What happens if you create the following associations:

namespace Acme\UserBundle\Entity;

use Doctrine\ORM\Mapping as ORM;

/**
 * Acme\UserBundle\Entity\User
 *
 * @ORM\Table()
 * @ORM\Entity
 */
class User
{
    /**
     * @var integer $id
     *
     * @ORM\Column(name="id", type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    private $id;

    /**
     * @ORM\OneToMany(targetEntity="Acme\FollowerBundle\Entity\Follower", mappedBy="followeduser")
     */
    protected $followers;

    /**
     * @ORM\OneToMany(targetEntity="Acme\FollowerBundle\Entity\Follower", mappedBy="followeeuser")
     */
    protected $followees;

    /**
     * Get id
     *
     * @return integer 
     */
    public function getId()
    {
        return $this->id;
    }
    public function __construct()
    {
        $this->followers = new \Doctrine\Common\Collections\ArrayCollection();
    $this->followees = new \Doctrine\Common\Collections\ArrayCollection();
    }

    /**
     * Add followers
     *
     * @param Acme\FollowerBundle\Entity\Follower $follower
     */
    public function addFollower(\Acme\FollowerBundle\Entity\Follower $follower)
    {
        $this->followers[] = $follower;
    }

    /**
     * Add followees
     *
     * @param Acme\FollowerBundle\Entity\Follower $followee
     */
    public function addFollowee(\Acme\FollowerBundle\Entity\Follower $followee)
    {
        $this->followees[] = $followee;
    }    

    /**
     * Get followers
     *
     * @return Doctrine\Common\Collections\Collection 
     */
    public function getFollowers()
    {
        return $this->followers;
    }

    /**
     * Get followees
     *
     * @return Doctrine\Common\Collections\Collection 
     */
    public function getFollowees()
    {
        return $this->followees;
    }
}

namespace Acme\FollowerBundle\Entity;

use Doctrine\ORM\Mapping as ORM;

/**
 * Acme\FollowerBundle\Entity\Follower
 *
 * @ORM\Table()
 * @ORM\Entity
 */
class Follower
{
    /**
     * @var integer $id
     *
     * @ORM\Column(name="id", type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    private $id;

    /**
     * @ORM\ManyToOne(targetEntity="Acme\UserBundle\Entity\User", inversedBy="followers")
     * @ORM\JoinColumn(name="user_id", referencedColumnName="id")
     */
    protected $followeduser;

    /**
     * @ORM\ManyToOne(targetEntity="Acme\UserBundle\Entity\User", inversedBy="followees")
     * @ORM\JoinColumn(name="followee_id", referencedColumnName="id")
     */
    protected $followeeuser;

    /**
     * Get id
     *
     * @return integer 
     */
    public function getId()
    {
        return $this->id;
    }

    /**
     * Set followeduser
     *
     * @param Acme\UserBundle\Entity\User $followeduser
     */
    public function setFolloweduser(\Acme\UserBundle\Entity\User $followeduser)
    {
        $this->followeduser = $followeduser;
    }

    /**
     * Get followeduser
     *
     * @return Acme\UserBundle\Entity\User 
     */
    public function getFolloweduser()
    {
        return $this->followeduser;
    }

    /**
     * Set followeeuser
     *
     * @param Acme\UserBundle\Entity\User $followeeuser
     */
    public function setFolloweeuser(\Acme\UserBundle\Entity\User $followeeuser)
    {
        $this->followeeuser = $followeeuser;
    }

    /**
     * Get followeeuser
     *
     * @return Acme\UserBundle\Entity\User 
     */
    public function getFolloweeuser()
    {
        return $this->followeeuser;
    }
}

I'm not sure if this would do the trick, I really don't have much time to test it, but if it doesn't, I thnk that it's on it's way. I'm using two relations, because you don't need a many to many. You need to reference that a user can have a lot of followers, and a follower can follow a lot of users, but since the "user" table is the same one, I did two relations, they have nothing to do with eachother, they just reference the same entity but for different things.

Try that and experiment what happens. You should be able to do things like:

$user->getFollowers();

$follower->getFollowedUser();

and you could then check if a user is being followed by a follower whose user_id equals $userThatIwantToCheck

and you could search in Followers for a Follower whose user = $user and followeduser=$possibleFriend

Answer 2

I was trying to have a many to many relationship with extra fields, and couldn't make it work either... The thing I read in a forum (can't remember where) was:

If you add data to a relationship, then it's not a relationship anymore. It's a new entity.

And it's the right thing to do. Create a new entity with the new fields, and if you need it, create a custom repository to add the methods you need.

A <--- Many to many with field ---> B

would become

A --One to many--> C (with new fields) <-- One to many--B

and of course, C has ManyToOne relationships with both A and B.

I searched everywhere on how to do this, but in the end, it's the right thing to do, if you add data, it's no longer a relationship.

You can also copy what contains usually do, or try to overwrite it in a custom repository, to do whatever you need it to do.

I hope this helps.