--- date: 2020-11-12 id: 4e20e5e5-06b6-4280-9cd0-7b08585a762b title: Symfony JSON Constraint --- # Syntax ``` php // src/Entity/Book.php namespace App\Entity; use Symfony\Component\Validator\Constraints as Assert; class Book { /** * @Assert\Json(message = "This is not valid JSON") */ protected $chapters; } ```