DNRoot::doDataTransfer PHP Method

    public function doDataTransfer($data, Form $form)
    {
        $this->setCurrentActionType(self::ACTION_SNAPSHOT);
        // Performs canView permission check by limiting visible projects
        $project = $this->getCurrentProject();
        if (!$project) {
            return $this->project404Response();
        }
        $dataArchive = null;
        // Validate direction.
        if ($data['Direction'] == 'get') {
            $validEnvs = $this->getCurrentProject()->DNEnvironmentList()->filterByCallback(function ($item) {
                return $item->canBackup();
            });
        } else {
            if ($data['Direction'] == 'push') {
                $validEnvs = $this->getCurrentProject()->DNEnvironmentList()->filterByCallback(function ($item) {
                    return $item->canRestore();
                });
            } else {
                throw new LogicException('Invalid direction');
            }
        }
        // Validate $data['EnvironmentID'] by checking against $validEnvs.
        $environment = $validEnvs->find('ID', $data['EnvironmentID']);
        if (!$environment) {
            throw new LogicException('Invalid environment');
        }
        $this->validateSnapshotMode($data['Mode']);
        // Only 'push' direction is allowed an association with an existing archive.
        if ($data['Direction'] == 'push' && isset($data['DataArchiveID']) && is_numeric($data['DataArchiveID'])) {
            $dataArchive = DNDataArchive::get()->byId($data['DataArchiveID']);
            if (!$dataArchive) {
                throw new LogicException('Invalid data archive');
            }
            if (!$dataArchive->canDownload()) {
                throw new SS_HTTPResponse_Exception('Not allowed to access archive', 403);
            }
        }
        $transfer = DNDataTransfer::create();
        $transfer->EnvironmentID = $environment->ID;
        $transfer->Direction = $data['Direction'];
        $transfer->Mode = $data['Mode'];
        $transfer->DataArchiveID = $dataArchive ? $dataArchive->ID : null;
        if ($data['Direction'] == 'push') {
            $transfer->setBackupBeforePush(!empty($data['BackupBeforePush']));
        }
        $transfer->write();
        $transfer->start();
        return $this->redirect($transfer->Link());
    }