func (br *backupService) UploadBackup(bucket, backupName string, metadata, backup, log io.Reader) error {
        // Uploading the log file is best-effort; if it fails, we log the error but it doesn't impact the
        // backup's status.
        logKey := getBackupLogKey(backupName, backupName)
        if err := br.seekAndPutObject(bucket, logKey, log); err != nil {
                br.logger.WithError(err).WithFields(logrus.Fields{
                        "bucket": bucket,
                        "key":    logKey,
                }).Error("Error uploading log file")
        }
        br.logger.Info("Completed log file upload")

        if metadata == nil {
                // If we don't have metadata, something failed, and there's no point in continuing. An object
                // storage bucket that is missing the metadata file can't be restored, nor can its logs be
                // viewed.
                br.logger.Debug("Metadata was nil, returning early")
                return nil
        }

        // upload metadata file
        metadataKey := getMetadataKey(backupName)
        if err := br.seekAndPutObject(bucket, metadataKey, metadata); err != nil {
                // failure to upload metadata file is a hard-stop
                br.logger.Info("Failed to upload metadata file")
                return err
        }
        br.logger.Info("Completed metadata upload")

        if backup != nil {
                // upload tar file
                if err := br.seekAndPutObject(bucket, getBackupContentsKey(backupName, backupName), backup); err != nil {
                        // try to delete the metadata file since the data upload failed
                        deleteErr := br.objectStore.DeleteObject(bucket, metadataKey)
                        br.logger.Info("Failed to upload backup")
                        return kerrors.NewAggregate([]error{err, deleteErr})
                }
                br.logger.Info("Completed backup upload")
        }

        return nil
}