JMS\Discriminator Example.

AbstractUser.php

<?php

namespace Entity;

use JMS\Serializer\Annotation as JMS;

/**
 * @JMS\Discriminator(field = "type", map = {
 *    "user": "Entity\User",
 *    "mod": "Entity\Moderator"
 * })
 */
abstract class AbstractUser
{
  /**
   * @JMS\Type("integer")
   */
  public $id;

  /**
   * @JMS\Type("string")
   */
  public $name;

  /**
   * @JMS\Type("string")
   */
  public $type;
}

Moderator.php

<?php

namespace Entity;

use JMS\Serializer\Annotation as JMS;

class Moderator extends AbstractUser
{
  /**
   * @JMS\Type("string")
   */
  public $foo;
}

/*
Serialized output:
*
{
    id: 1,
    name: "a Moderator name",
    type: "mod",
    foo: "..."
}
*/

User.php

<?php

namespace Entity;

use JMS\Serializer\Annotation as JMS;

class User extends AbstractUser
{
  /**
   * @JMS\Type("string")
   */
  public $bar;
}

/*
Serialized output:
*
{
    id: 1,
    name: "a User name",
    type: "user",
    bar: "..."
}
*/