code: func NewImageService(config ImageServiceConfig) *ImageService {
  	logrus.Debugf("Max Concurrent Downloads: %d", config.MaxConcurrentDownloads)
  	logrus.Debugf("Max Concurrent Uploads: %d", config.MaxConcurrentUploads)
  	return &ImageService{
  		containers:                config.ContainerStore,
  		distributionMetadataStore: config.DistributionMetadataStore,
  		downloadManager:           xfer.NewLayerDownloadManager(config.LayerStores, config.MaxConcurrentDownloads),
  		eventsService:             config.EventsService,
  		imageStore:                config.ImageStore,
  		layerStores:               config.LayerStores,
  		referenceStore:            config.ReferenceStore,
  		registryService:           config.RegistryService,
  		uploadManager:             xfer.NewLayerUploadManager(config.MaxConcurrentUploads),
  	}
  }
docs: // NewImageService returns a new ImageService from a configuration