validation.md

Validation

API Platform Core uses the Symfony Validator component to validate entities.

Without specific configuration, it uses the default validation group, but this behavior is customizable.

Using Validation Groups

Built-in actions are able to leverage Symfony's validation groups.

You can customize them by editing the resource configuration and add the groups you want to use when the validation occurs:

<?php
// src/AppBundle/Entity/Book.php

use ApiPlatform\Core\Annotation\ApiResource;
use Symfony\Component\Validator\Constraints as Assert;

/**
 * @ApiResource(attributes={"validation_groups"={"a", "b"}})
 */
class Book
{
    /**
     * @Assert\NotBlank(groups={"a"})
     */
    private $name;

    /**
     * @Assert\NotNull(groups={"b"})
     */
    private $author;

    // ...
}

With the previous configuration, the validations groups a and b will be used when validation is performed.

Like for serialization groups, you can specify validation groups globally or on a per operation basis.

Of course, you can use XML or YAML configuration format instead of annotations if you prefer.

You may also pass in a group sequence in place of the array of group names.

Dynamic Validation Groups

If you need to dynamically determine which validation groups to use for an entity in different scenarios, just pass in a callable. The callback will receive the entity object as its first argument, and should return an array of group names or a group sequence.

In the following example, we use a static method to return the validation groups:

<?php
// src/AppBundle/Entity/Book.php

use ApiPlatform\Core\Annotation\ApiResource;
use Symfony\Component\Validator\Constraints as Assert;

/**
 * @ApiResource(
 *     attributes={"validation_groups"={Book::class, "validationGroups"}}
 * )
 */
class Book
{
    /**
     * Return dynamic validation groups.
     *
     * @param self $book Contains the instance of Book to validate.
     *
     * @return string[]
     */
    public static function validationGroups(self $book)
    {
        return ['a'];
    }

    /**
     * @Assert\NotBlank(groups={"a"})
     */
    private $name;

    /**
     * @Assert\NotNull(groups={"b"})
     */
    private $author;

    // ...
}

Alternatively, you can use a service to retrieve the groups to use:

<?php
// src/AppBundle/Validator/AdminGroupsGenerator.php

namespace AppBundle\Validator;

use AppBundle\Entity\Book;
use Symfony\Component\Security\Core\Authorization\AuthorizationCheckerInterface;

final class AdminGroupsGenerator
{
    private $authorizationChecker;

    public function __construct(AuthorizationCheckerInterface $authorizationChecker)
    {
        $this->authorizationChecker = $authorizationChecker;
    }

    public function __invoke(Book $book): array
    {
        return $this->authorizationChecker->isGranted('ROLE_ADMIN', $book) ? ['a', 'b'] : ['a'];
    }
}

This class selects the groups to apply regarding the role of the current user: if the current user has the ROLE_ADMIN role, groups a and b are returned. In other cases, just a is returned.

This class is automatically registered as a service thanks to the autowiring feature of the Symfony Dependency Injection Component. Just note that this service must be public.

Then, configure the entity class to use this service to retrieve validation groups:

<?php
// src/AppBundle/Entity/Book.php

namespace AppBundle\Entity;

use ApiPlatform\Core\Annotation\ApiResource;
use AppBundle\Validator\AdminGroupsGenerator;
use Symfony\Component\Validator\Constraints as Assert;

/**
 * @ApiResource(attributes={"validation_groups"=AdminGroupsGenerator::class})
 */
class Book
{
    /**
     * @Assert\NotBlank(groups={"a"})
     */
    private $name;

    /**
     * @Assert\NotNull(groups={"b"})
     */
    private $author;

    // ...
}