code: func (si *shareImporter) serveProgress(w http.ResponseWriter, r *http.Request) {
  	si.mu.RLock()
  	defer si.mu.RUnlock()
  	httputil.ReturnJSON(w, camtypes.ShareImportProgress{
  		FilesSeen:   si.seen,
  		FilesCopied: si.copied,
  		Running:     si.running,
  		Assembled:   si.assembled,
  		BlobRef:     si.br,
  	})
  }
docs: // serveProgress serves the state of the currently running importing process