extensions.md

Extensions

The validator's architecture allows to replenish its missing functionality via extensions. A few already exist and are available for usage. Note that they are not official in terms of not being part of Yiisoft packages.

Scenarios

Yii2 has a scenarios feature out of the box. Those of you that used it might be wondering why it's no longer the case with this package. Well, we think that from an architectural point of view, it's a design flaw. What seems to be more concise at first, tends to grow and became harder to read and maintain with a bigger amount of attributes/scenarios/business logic, while rewriting cost can be quite high. This was proved in practice, so this approach is discouraged and the recommended way with this package is using separate DTO for each scenario. Sure, this will lead to some code duplication, but it's acceptable and will pay off in the future. Anyway, we decided to make it available through an extension, but use it with caution.

Yii Validator Scenarios (vjik/yii-validator-scenarios) package from a core team member Sergei Predvoditelev adds special On rule which allows to wrap other rules by declaring specific scenarios.

An example of the class using scenarios:

use Vjik\Yii\ValidatorScenarios\On;
use Yiisoft\Validator\Rule\Email;
use Yiisoft\Validator\Rule\Length;
use Yiisoft\Validator\Rule\Required;

final class UserDto
{
    public function __construct(
        #[On(
            'signup',
            [new Required(), new Length(min: 7, max: 10)]
        )]
        public string $name,

        #[Required]
        #[Email]
        public string $email,

        #[On(
            ['login', 'signup'],
            [new Required(), new Length(min: 8)],
        )]
        public string $password,
    ) {
    }
}

An active scenario for current validation is determined by a dedicated validation context parameter:

use Yiisoft\Validator\ValidationContext;
use Yiisoft\Validator\Validator;

$context = new ValidationContext([On::SCENARIO_PARAMETER => 'signup']);
$result = (new Validator())->validate($userDto, context: $context));

Wrapper for Symfony rules

Yii Validator Symfony Rule (vjik/yii-validator-symfony-rule) package from a core team member Sergei Predvoditelev adapts constraints from Symfony framework to be used as rules in Yii Validator.

Using it is straightforward, all you have to do is wrap a Symfony constraint (or a list of them) with SymfonyRule rule provided by this extension.

use Symfony\Component\Validator\Constraints\{CssColor, NotEqualTo, Positive};
use Vjik\Yii\ValidatorSymfonyRule\SymfonyRule;
use Yiisoft\Validator\Rule\Length;
use Yiisoft\Validator\Rule\Required;

final class Car
{
    #[Required]
    #[Length(min: 3, skipOnError: true)]
    public string $name = '';

    #[Required]
    // A single constraint.
    #[SymfonyRule(
        new CssColor(CssColor::RGB),
        skipOnError: true,
    )]
    public string $cssColor = '#1123';

    // Multiple constraints.
    #[SymfonyRule([
        new Positive(),
        new NotEqualTo(13),
    ])]
    public int $number = 13;
}