// copyContent attempts to load and serve the provided blob. If req != nil and writer is an instance of http.ResponseWriter,
// response headers will be set and range requests honored.
func (pbs *pullthroughBlobStore) copyContent(store distribution.BlobStore, ctx context.Context, dgst digest.Digest, writer io.Writer, req *http.Request) (distribution.Descriptor, error) {
desc, err := store.Stat(ctx, dgst)
if err != nil {
return distribution.Descriptor{}, err
}
remoteReader, err := store.Open(ctx, dgst)
if err != nil {
return distribution.Descriptor{}, err
}
rw, ok := writer.(http.ResponseWriter)
if ok {
setResponseHeaders(rw, desc.Size, desc.MediaType, dgst)
// serve range requests
if req != nil {
http.ServeContent(rw, req, desc.Digest.String(), time.Time{}, remoteReader)
return desc, nil
}
}
if _, err = io.CopyN(writer, remoteReader, desc.Size); err != nil {
return distribution.Descriptor{}, err
}
return desc, nil
}
func pushLayer(ctx context.Context, address, imageDir string,
blobs distribution.BlobStore) (descriptor distribution.Descriptor, err error) {
fmt.Printf("push layer: %s", address)
layer, err := os.Open(filepath.Join(imageDir, address, "layer.tar"))
if err != nil {
log.Printf("Error reading embedded tar: %v", err)
return
}
defer layer.Close()
stat, err := layer.Stat()
digester := digest.Canonical.New()
bar := pb.New(int(stat.Size())).SetUnits(pb.U_BYTES)
bar.Start()
writer, err := blobs.Create(ctx)
if err != nil {
log.Printf("Error creating blob writer: %v", err)
return
}
_, err = io.Copy(io.MultiWriter(writer, bar, digester.Hash()), layer)
if err != nil {
log.Printf("Error copying to blob writer: %v", err)
return
}
descriptor, err = writer.Commit(ctx, distribution.Descriptor{
Digest: digester.Digest(),
})
if err != nil {
log.Printf("Error commiting blob writer: %v", err)
return
}
bar.Finish()
return
}