fix track tagging

src/metadata-writer/flacmetata.ts

@@ -29,6 +29,7 @@ export const writeMetadataFlac = (
     flac.setTag('LYRICS=' + track.LYRICS.LYRICS_TEXT);
   }
 
+  if (track.SNG_CONTRIBUTORS) {
     if (track.SNG_CONTRIBUTORS.composer) {
       flac.setTag('COMPOSER=' + track.SNG_CONTRIBUTORS.composer.join(', '));
     }
@@ -50,6 +51,7 @@ export const writeMetadataFlac = (
     if (track.SNG_CONTRIBUTORS.mixer) {
       flac.setTag('MIXER=' + track.SNG_CONTRIBUTORS.mixer.join(', '));
     }
+  }
 
   if (cover) {
     flac.importPicture(cover, dimension, 'image/jpeg');

src/metadata-writer/id3.ts

@@ -42,13 +42,13 @@ export const writeMetadataMp3 = (buffer: Buffer, track: trackType, cover?: Buffe
     value: track.DURATION,
   });
 
+  if (track.SNG_CONTRIBUTORS) {
     if (track.SNG_CONTRIBUTORS.composer) {
       writer.setFrame('TXXX', {
         description: 'COMPOSER',
         value: track.SNG_CONTRIBUTORS.composer.join(', '),
       });
     }
-
     if (track.SNG_CONTRIBUTORS.writer) {
       writer.setFrame('TXXX', {
         description: 'LYRICIST',
@@ -67,6 +67,7 @@ export const writeMetadataMp3 = (buffer: Buffer, track: trackType, cover?: Buffe
         value: track.SNG_CONTRIBUTORS.producer.concat(track.SNG_CONTRIBUTORS.engineer).join(', '),
       });
     }
+  }
 
   if (track.LYRICS) {
     writer.setFrame('USLT', {

src/types/tracks.ts

@@ -44,7 +44,7 @@ interface songType {
   SMARTRADIO: string; // 0
   SNG_ID: string; // '3135556'
   SNG_TITLE: string; // 'Harder, Better, Faster, Stronger'
-  SNG_CONTRIBUTORS: {
+  SNG_CONTRIBUTORS?: {
     main_artist: string[]; //['Daft Punk']
     author?: string[]; // ['Edwin Birdsong', 'Guy-Manuel de Homem-Christo', 'Thomas Bangalter']
     composer?: string[];