Added InitVideo() function to initialize Format.Video.Chunklist

format.go

@@ -34,6 +34,28 @@ type Format struct {
 	Subtitles   []*Subtitle
 }
 
+// InitVideo initializes the Format.Video completely.
+// The Format.Video.Chunklist pointer is, by default, nil because an additional
+// request must be made to receive its content. The request is not made when
+// initializing a Format struct because it would probably cause an intense overhead
+// since Format.Video.Chunklist is only used sometimes
+func (f *Format) InitVideo() error {
+	if f.Video.Chunklist == nil {
+		resp, err := f.crunchy.Client.Get(f.Video.URI)
+		if err != nil {
+			return err
+		}
+		defer resp.Body.Close()
+
+		playlist, _, err := m3u8.DecodeFrom(resp.Body, true)
+		if err != nil {
+			return err
+		}
+		f.Video.Chunklist = playlist.(*m3u8.MediaPlaylist)
+	}
+	return nil
+}
+
 func (f *Format) Download(downloader Downloader) error {
 	if _, err := os.Stat(downloader.Filename); err == nil && !downloader.IgnoreExisting {
 		return fmt.Errorf("file %s already exists", downloader.Filename)