open Nftables

let nftables = [
  Flush FlushRuleset;
  Add (AddRule {
      family = Inet;
      table = "filter";
      chain = "forward";
      expr =
        [
          Log { prefix = Some "test"; group = None };
          Match {
            left = Payload (Udp UdpSport);
            right = Set [Number 53];
            op = NotEq };
          Verdict Accept
        ]
    })
]

let json = json_of_nftables nftables

let () =
  print_string (Yojson.Basic.to_string json);
  print_newline ()