{
  "manageEntity": {
    "action": "Create",
    "entityId": "1464837538",
    "entityType": "Track",
    "metadata": "{\"cid\":\"\",\"data\":{\"duration\":288,\"genre\":\"Electronic\",\"is_unlisted\":true,\"orig_file_cid\":\"baeaaaiqsebvdpeyhqsodn4ojvyh6oamwgghitirwngdqa73fttqhbvs3rly42\",\"owner_id\":319129,\"title\":\"A\",\"track_cid\":\"baeaaaiqseaptretm4kthwdozzzjze6x5k4eapr2srhhs5lqpzwtjgfh7eyeuo\"}}",
    "nonce": "1775806502986936383",
    "signature": "0x47499a7d6cfb000845042db8558028dfd77a4b3cff8158258a638fd54c23d9e05d9f97c3fa382e4e79cff19125c031d389621d87a1de87de5f8b7cca5f0b6c5b1b",
    "signer": "0x43e766989e99A80eCF18BF165011e01fbFC3A676",
    "userId": "319129"
  }
}