Define Constraints as Attributes

Syntax

// src/Entity/Author.php
namespace App\Entity;

// …
use Symfony\Component\Validator\Constraints as Assert;

class Author
{
/**
* @Assert\Choice(
* choices = { “fiction”, “non-fiction” },
* message = “Choose a valid genre.”
* )
*/
private $genre;

// ...

}

// src/Entity/Author.php
namespace App\Entity;

// …
use Symfony\Component\Validator\Constraints as Assert;

class Author
{
#[Assert\Choice(
choices: [‘fiction’, ‘non-fiction’],
message: ‘Choose a valid genre.’,
)]
private $genre;

// ...

}

The following composite constraints can’t be used with attributes:

All
[AtLeastOneOf Constraint](AtLeastOneOf Constraint)
Collection
[Compound Constraint](Compound Constraint) (abstract)
- Existance (abstract)
  - Required
  - Optional
[Sequentially Constraint](Sequentially Constraint)

The reason is that they would require nested attributes and PHP doesn’t support that feature yet