func()

in lib/dockerregistry/transfer/rw_transferer.go [129:174]

• 44 lines of code
• 8 McCabe index (conditional complexity)

func (t *ReadWriteTransferer) downloadFromOrigin(ctx context.Context, namespace string, d core.Digest) (store.FileReader, error) {
	ctx, span := t.tracer.Start(ctx, "registry.download_from_origin",
		trace.WithAttributes(
			attribute.String("namespace", namespace),
			attribute.String("blob.digest", d.Hex()),
		),
	)
	defer span.End()

	tmp := fmt.Sprintf("%s.%s", d.Hex(), uuid.Generate().String())
	if err := t.cas.CreateUploadFile(tmp, 0); err != nil {
		span.RecordError(err)
		span.SetStatus(codes.Error, "failed to create upload file")
		return nil, fmt.Errorf("create upload file: %s", err)
	}
	w, err := t.cas.GetUploadFileReadWriter(tmp)
	if err != nil {
		span.RecordError(err)
		span.SetStatus(codes.Error, "failed to get upload writer")
		return nil, fmt.Errorf("get upload writer: %s", err)
	}
	defer closers.Close(w)
	if err := t.originCluster.DownloadBlob(ctx, namespace, d, w); err != nil {
		if err == blobclient.ErrBlobNotFound {
			span.SetStatus(codes.Error, "blob not found")
			return nil, ErrBlobNotFound
		}
		span.RecordError(err)
		span.SetStatus(codes.Error, "origin download failed")
		return nil, fmt.Errorf("origin: %s", err)
	}
	if err := t.cas.MoveUploadFileToCache(tmp, d.Hex()); err != nil && !os.IsExist(err) {
		span.RecordError(err)
		span.SetStatus(codes.Error, "failed to move to cache")
		return nil, fmt.Errorf("move upload file to cache: %s", err)
	}
	blob, err := t.cas.GetCacheFileReader(d.Hex())
	if err != nil {
		span.RecordError(err)
		span.SetStatus(codes.Error, "failed to read cached blob")
		return nil, fmt.Errorf("get cache file: %s", err)
	}

	span.SetStatus(codes.Ok, "download completed")
	return blob, nil
}