https://xxxxxx/v4/live_engine_http_srv/set_room_metadata?
sdkappid=88888888&identifier=admin&usersig=xxx&random=99999999&contenttype=json

{
  "RoomId": "live-room",
  "Metadata": [ // The key count is limited to 10, with each key length restricted to 50 bytes or less. Individual values can be up to 2KB in size, while the aggregate size of all values should not surpass 16KB.
                {
                    "Key":"key1",  //If the key exists, it will be updated; otherwise, it will be added
                    "Value":"value1"
                },
                {
                    "Key":"key2",
                    "Value":"value2"
                }
            ]
}

{
  "ActionStatus": "OK",
  "ErrorInfo": "",
  "ErrorCode": 0,
  "RequestId": "Id-8c9858f01e954611ae2d4c1b1ed7d583-O-Seq-52720"
}