type Blob interface {
	Check() error
	Size() int64
	FetchedSize() int64
	ReadAt(p []byte, offset int64, opts ...Option) (int, error)
	Cache(offset int64, size int64, opts ...Option) error
	Refresh(ctx context.Context, host source.RegistryHosts, refspec reference.Spec, desc ocispec.Descriptor) error
	Close() error
}

type Fetcher interface {
	Fetch(ctx context.Context, off int64, size int64) (io.ReadCloser, error)
	Check() error
	GenID(off int64, size int64) string
}

type Handler interface {
	Handle(ctx context.Context, desc ocispec.Descriptor) (fetcher Fetcher, size int64, err error)
}

type Option func(*options)

type Resolver struct {
	// contains filtered or unexported fields
}