{
  "manageEntity": {
    "action": "Save",
    "entityId": "664712593",
    "entityType": "Track",
    "nonce": "0xa159c3d851ca94bcf5c6596399e143ccb2cc8ed7d2ed3e0100ea1e4e7739762d",
    "signature": "0x75374d50bd2f2d6797ffbaeb08014169596fc293b23682d1bc07c76c45331a9d5bf3c404a98cfef16c3d43db23dd003122819d3f8757f4866b5f90f22a260bb01c",
    "signer": "0xD24271e3B8CCFB603860EA392E94eD5AE2538703",
    "userId": "456716469"
  }
}