Add option to download playlist

server/subsonic/helpers.go

@@ -269,6 +269,10 @@ func getEntityByID(ctx context.Context, ds model.DataStore, id string) (interfac
 	if err == nil {
 		return al, nil
 	}
+	pls, err := ds.Playlist(ctx).Get(id)
+	if err == nil {
+		return pls, nil
+	}
 	mf, err := ds.MediaFile(ctx).Get(id)
 	if err == nil {
 		return mf, nil

server/subsonic/stream.go

@@ -109,6 +109,9 @@ func (c *StreamController) Download(w http.ResponseWriter, r *http.Request) (*re
 	case *model.Artist:
 		setHeaders(v.Name)
 		err = c.archiver.ZipArtist(ctx, id, w)
+	case *model.Playlist:
+		setHeaders(v.Name)
+		err = c.archiver.ZipPlaylist(ctx, id, w)
 	default:
 		err = model.ErrNotFound
 	}