Class Yiisoft\Validator\Rule\Composite

Allows to group multiple rules for validation. It's helpful when skipOnEmpty, skipOnError or when options are the same for every rule in the set.

For example, with the same when closure, without using composite it's specified explicitly for every rule:

$when = static function ($value, ValidationContext $context): bool {
    return $context->getDataSet()->getPropertyValue('country') === Country::USA;
};
$rules = [
    new Required(when: $when),
    new Length(min: 1, max: 50, skipOnEmpty: true, when: $when),
];

When using composite, specifying it only once will be enough:

$rule = new Composite([
    new Required(),
    new Length(min: 1, max: 50, skipOnEmpty: true),
    when: static function ($value, ValidationContext $context): bool {
        return $context->getDataSet()->getPropertyValue('country') === Country::USA;
    },
]);

Another use case is reusing this rule group across different places. It's possible by creating own extended class and setting the properties in the constructor:

class MyComposite extends Composite
{
    public function __construct()
    {
        $this->rules = [
            new Required(),
            new Length(min: 1, max: 50, skipOnEmpty: true),
        ];
        $this->when = static function ($value, ValidationContext $context): bool {
            return $context->getDataSet()->getPropertyValue('country') === Country::USA;
        };
    }
};

See also Yiisoft\Validator\Rule\CompositeHandler Corresponding handler performing the actual validation.