Frontend\Modules\Mailmotor\Validator\Constraints\EmailUnsubscriptionValidator::validate PHP Method

    public function validate($value, Constraint $constraint)
    {
        try {
            // The email doesn't exists in the mailing list
            if (!$this->subscriber->exists($value)) {
                $this->context->buildViolation($constraint->notExistsMessage)->addViolation();
            } elseif ($this->subscriber->isUnsubscribed($value)) {
                $this->context->buildViolation($constraint->alreadyUnsubscribedMessage)->addViolation();
            }
            // fallback for when no mail-engine is chosen in the Backend
        } catch (NotImplementedException $e) {
            // do nothing
        }
    }