How to convert a nested json to string?

[abcfy2]

Here is my rubydebug output:

{
    "@timestamp" => 2016-04-01T06:17:16.494Z,
          "host" => "shifudao",
          "type" => "rtds",
      "loglevel" => "WARN",
     "classname" => "hawkeyes.rtds.gate.protocol.frametype.SamplerReportData",
     "logdetail" => {
        "message" => "设备00004650数据上报帧里的sid为空，可能未发过心跳，丢弃！",
         "action" => "fireEquipmentDataArrived(String writeHandlerID, String sid, Vertx vertx, List result)",
            "sid" => nil,
         "params" => {
            "writeHandlerID" => "b6728301-653e-488c-91b8-fc2aa52c1312",
                       "sid" => nil,
                    "result" => [
                [0] {
                      "eId" => "00004650",
                     "date" => 963328184494,
                    "items" => [
                        [0] [
                            [0] 1,
                            [1] [
                                [0] 74,
                                [1] 0,
                                [2] 0,
                                [3] 0
                            ]
                        ],
                        [1] [
                            [0] 2,
                            [1] [
                                [0] -119,
                                [1] 0,
                                [2] 0,
                                [3] 0
                            ]
                        ],
                        [2] [
                            [0] 3,
                            [1] [
                                [0] 12,
                                [1] 0,
                                [2] 0,
                                [3] 0
                            ]
                        ],
                        [3] [
                            [0] 4,
                            [1] [
                                [0] 12,
                                [1] 0,
                                [2] 0,
                                [3] 0
                            ]
                        ],
                        [4] [
                            [0] 5,
                            [1] [
                                [0] 110,
                                [1] 5,
                                [2] 0,
                                [3] 0
                            ]
                        ],
                        [5] [
                            [0] 6,
                            [1] [
                                [0] 61,
                                [1] 5,
                                [2] 0,
                                [3] 0
                            ]
                        ],
                        [6] [
                            [0] 7,
                            [1] [
                                [0] -18,
                                [1] 5,
                                [2] 0,
                                [3] 0
                            ]
                        ],
                        [7] [
                            [0] 8,
                            [1] [
                                [0] 3,
                                [1] 8,
                                [2] 0,
                                [3] 0
                            ]
                        ],
                        [8] [
                            [0] 9,
                            [1] [
                                [0] 0,
                                [1] 0,
                                [2] 0,
                                [3] 0
                            ]
                        ]
                    ]
                }
            ]
        }
    },
      "@version" => "1"
}

I want to convert logdetail.params to a string.

But it seems not support by mutate now. How could I do ? And would this feature be add in the future?

[ph]

You need custom ruby code for that, you might to check the https://www.elastic.co/guide/en/logstash/current/plugins-filters-ruby.html

[abcfy2]

Thanks. Would you please give me an example? I'm not good at ruby, thanks.

[abcfy2]

I've already fix.

[slan77]

Could you share the way? I have the same issue now. Thanks!

[guangwong]

+1

[shenshouer]

+1 @abcfy2

[shenshouer]

I got it just like:

  ruby {
    code => 'event.set("body", event.get("rbody").to_s)'
  }