Phalcon PHP validation Uniqueness but allow empty values

Question

I have the following validation:

use Phalcon\Validation;
use Phalcon\Validation\Validator\Uniqueness;

class Users extends BaseModel {
    public function validation() {
        $validator = new Validation();
        $validator->add('some_data', new Uniqueness([
                    'message' => 'this field must be unique or epmty'
        ]));
        // some other rules (...)
        return $this->validate($validator);
    }
}

The question is how to allow pass empty data. I'd like to save in database NULL if data is empty or unique value if it's passed.

Answer 1

You should just be able to do the following in your model class:

public function validation()
    {
        $validator = new Validation();
        $validator->add(
            'example',
            new Uniqueness(
                [
                    'message' => 'Example must be unique',
                    'allowEmpty' => true,
                ]
            )
        );
        return $this->validate($validator);
    }