{
  "manageEntity": {
    "action": "Create",
    "entityId": "1452422838",
    "entityType": "Track",
    "metadata": "{\"cid\":\"\",\"access_authorities\":[\"0x8C5ba66083D1ef52d5Caa8b250E7b66f4C21E272\"],\"data\":{\"title\":\"test audio file\",\"genre\":\"Electronic\",\"track_cid\":\"baeaaaiqseafkjbjc3lrshhdxvyikrpho7bjymlxr3nsrsdcboerse3rus5rcg\",\"access_authorities\":[\"0x8C5ba66083D1ef52d5Caa8b250E7b66f4C21E272\"],\"duration\":28,\"orig_file_cid\":\"baeaaaiqsed5ggot4kgd2jx57e4gmbssv2vlm6exj6bzz5tag4m4kqcpujpk2i\",\"orig_filename\":\"test_audio_file.mp3\",\"owner_id\":748327774}}",
    "nonce": "0x076cbf994fdd946bc160419cbeefac8dd5ae382758d6458b5bdead2c88ed9286",
    "signature": "0x3da6ef0ea724d9cab423d845ed0de683baa74639950571e2cd4cae19accba71e74a99c797f8c2e86fa52627b86236e7cc4c650e61571594991ae2d31ecea18901b",
    "signer": "0x8C5ba66083D1ef52d5Caa8b250E7b66f4C21E272",
    "userId": "748327774"
  }
}