Guide

Validate Data on a Delete Operation

// src/App/Validator.php
namespace App\Validator;
use Symfony\Component\Validator\Constraint;
use Symfony\Component\Validator\ConstraintValidator;
#[\Attribute]
class AssertCanDelete extends Constraint
{
    public string $message = 'The string "{{ string }}" contains an illegal character: it can only contain letters or numbers.';
    public string $mode = 'strict';
}

// src/App/Validator.php
namespace App\Validator;
use Symfony\Component\Validator\Constraint;
use Symfony\Component\Validator\ConstraintValidator;
#[\Attribute]
class AssertCanDelete extends Constraint
{
    public string $message = 'The string "{{ string }}" contains an illegal character: it can only contain letters or numbers.';
    public string $mode = 'strict';
}

And a custom validator following Symfony's naming conventions.

// src/App/Validator.php
namespace App\Validator;
use Symfony\Component\Validator\ConstraintValidator;
use Symfony\Component\Validator\Constraint;
class AssertCanDeleteValidator extends ConstraintValidator
{
    public function validate(mixed $value, Constraint $constraint)
    {
        /* TODO: Implement validate() method. */
    }
}

// src/App/Validator.php
namespace App\Validator;
use Symfony\Component\Validator\ConstraintValidator;
use Symfony\Component\Validator\Constraint;
class AssertCanDeleteValidator extends ConstraintValidator
{
    public function validate(mixed $value, Constraint $constraint)
    {
        /* TODO: Implement validate() method. */
    }
}

By default, validation is not triggered during a DELETE operation and we need to trigger validation manually.

// src/App/ApiResource.php
namespace App\ApiResource;
use ApiPlatform\Metadata\Delete;
use App\State\BookRemoveProcessor;
use App\Validator\AssertCanDelete;
use Doctrine\ORM\Mapping as ORM;
#[ORM\Entity]
#[Delete(validationContext: ['groups' => ['deleteValidation']], processor: BookRemoveProcessor::class)]

// src/App/ApiResource.php
namespace App\ApiResource;
use ApiPlatform\Metadata\Delete;
use App\State\BookRemoveProcessor;
use App\Validator\AssertCanDelete;
use Doctrine\ORM\Mapping as ORM;
#[ORM\Entity]
#[Delete(validationContext: ['groups' => ['deleteValidation']], processor: BookRemoveProcessor::class)]

Here we use the previously created constraint on the class directly.

#[AssertCanDelete(groups: ['deleteValidation'])]
class Book
{
    #[ORM\Id, ORM\Column, ORM\GeneratedValue]
    private ?int $id = null;
    #[ORM\Column]
    public string $title = '';
}

#[AssertCanDelete(groups: ['deleteValidation'])]
class Book
{
    #[ORM\Id, ORM\Column, ORM\GeneratedValue]
    private ?int $id = null;
    #[ORM\Column]
    public string $title = '';
}

Then, we will trigger the validation within a processor. the removal into the Database.

// src/App/State.php
namespace App\State;
use ApiPlatform\Doctrine\Common\State\RemoveProcessor as DoctrineRemoveProcessor;
use ApiPlatform\Metadata\Operation;
use ApiPlatform\State\ProcessorInterface;
use ApiPlatform\Validator\ValidatorInterface;
use Symfony\Component\DependencyInjection\Attribute\Autowire;
class BookRemoveProcessor implements ProcessorInterface
{
    public function __construct(

// src/App/State.php
namespace App\State;
use ApiPlatform\Doctrine\Common\State\RemoveProcessor as DoctrineRemoveProcessor;
use ApiPlatform\Metadata\Operation;
use ApiPlatform\State\ProcessorInterface;
use ApiPlatform\Validator\ValidatorInterface;
use Symfony\Component\DependencyInjection\Attribute\Autowire;
class BookRemoveProcessor implements ProcessorInterface
{
    public function __construct(

We're decorating API Platform's Doctrine processor to persist the removal.

        #[Autowire(service: 'api_platform.doctrine.orm.state.remove_processor')]
        private DoctrineRemoveProcessor $doctrineProcessor,
        private ValidatorInterface $validator,
    ) {
    }
    public function process($data, Operation $operation, array $uriVariables = [], array $context = [])
    {

        #[Autowire(service: 'api_platform.doctrine.orm.state.remove_processor')]
        private DoctrineRemoveProcessor $doctrineProcessor,
        private ValidatorInterface $validator,
    ) {
    }
    public function process($data, Operation $operation, array $uriVariables = [], array $context = [])
    {

First step is to trigger Symfony's validation.

        $this->validator->validate($data, ['groups' => ['deleteValidation']]);

        $this->validator->validate($data, ['groups' => ['deleteValidation']]);

Then we persist the data.

        $this->doctrineProcessor->process($data, $operation, $uriVariables, $context);
    }
}

        $this->doctrineProcessor->process($data, $operation, $uriVariables, $context);
    }
}

TODO move this to reference somehow This operation uses a Callable as group so that you can vary the Validation according to your dataset new Get(validationContext: ['groups' =>])

Sequential Validation Groups

If you need to specify the order in which your validation groups must be tested against, you can use a group sequence.