code: func (i IndexFile) Add(md *chart.Metadata, filename, baseURL, digest string) {
  	u := filename
  	if baseURL != "" {
  		var err error
  		_, file := filepath.Split(filename)
  		u, err = urlutil.URLJoin(baseURL, file)
  		if err != nil {
  			u = path.Join(baseURL, file)
  		}
  	}
  	cr := &ChartVersion{
  		URLs:     []string{u},
  		Metadata: md,
  		Digest:   digest,
  		Created:  time.Now(),
  	}
  	if ee, ok := i.Entries[md.Name]; !ok {
  		i.Entries[md.Name] = ChartVersions{cr}
  	} else {
  		i.Entries[md.Name] = append(ee, cr)
  	}
  }
docs: // Add adds a file to the index
  // This can leave the index in an unsorted state