Question

I want to ensure no duplicate username’s when validating my entity

/**
 * @var string $name
 *
 * @ORM\Column(name="name", type="string", length=32)
 * @Assert\NotBlank();
 * @Assert\Callback(methods={"isUniqueUsername"})
 */
private $name;

I suppose I need to use the Validator Callback. Then I will have to query database for users with that username, so I require entity manager? How do I access it? And access it “correctly”? Do I use a validator class instead? It seems quite troublesome to create a class just to validate 1 field?

Answer 1

In symfony2, there is a Unique validator you can use to ensure that a username, email address or any other field is unique. When using annotations, it works like this:

use Symfony\Bridge\Doctrine\Validator\Constraints as Unique;

/**
 * @ORM\Entity
 * @ORM\Table
 * @Unique\UniqueEntity(fields={"email"},message="Your email is already registered")
 */
class User{
  // ...
}

When trying to add a user through a form, you should get the message stated in the Unique annotation.