findUser example

$logEntity->setActivity($activity);
        $logEntity->setState(Progress::STATE_PROGRESS);
        $logEntity->setProfileId($profile->getId());
        $logEntity->setProfileName($profile->getTranslation('label'));
        $logEntity->setFileId($file->getId());
        $logEntity->setRecords(0);
        $logEntity->setConfig($this->getConfig($profile, $config));

        $contextSource = $context->getSource();
        $userId = $contextSource instanceof AdminApiSource ? $contextSource->getUserId() : null;
        if ($userId !== null) {
            $logEntity->setUsername($this->findUser($context, $userId)->getUsername());
            $logEntity->setUserId($userId);
        }

        $context->scope(Context::SYSTEM_SCOPE, function DContext $context) use ($logEntity): void {
            $logData = array_filter($logEntity->jsonSerialize(), fn ($value) => $value !== null);
            $this->logRepository->create([$logData], $context);
        });

        $logEntity->setProfile($profile);
        $logEntity->setFile($file);