help with Jolt tarnsformation

[#1]

Hi All, 

Looking for some help with JOLT transformatio, which i am completely new.

my input JSON looks like this 

{
	"type": "delete",
	"timestamp": 1681484884000,
	"binlog_filename": "bin.000003",
	"binlog_position": 6378700,
	"database": "db1",
	"table_name": "records",
	"table_id": 108,
	"columns": [{
		"id": 1,
		"name": "id",
		"column_type": 4,
		"value": 259
	}, {
		"id": 2,
		"name": "index_id",
		"column_type": 4,
		"value": 1
	}, {
		"id": 3,
		"name": "state_id",
		"column_type": 4,
		"value": 1
	}]
}

This is from mysql binlogs.

I want to transform it to have a single field..

[{
	"id": 259
}]

from one of the tutorials here in cloudera comminity, i saw this JOLT transformation.

[
  {
    "operation": "shift",
    "spec": {
      "columns": {
        "*": {
          "@(value)": "[#1].@(1,name)"
        }
      }
    }
  }
]

But it gives all fileds.. but I just need one filed which is the ID. I need to drop rest all fields.. 

Can someone please help in this regards.

[#2 · Accepted solution]

Hi,

If you are looking to set the id value for the first element in the columns array you can use the following spec:

[
  {
    "operation": "shift",
    "spec": {
      "columns": {
        "0": {
          "value": "[].@(1,name)"
        }
      }
    }
  }
]

If that helps please accept solution.

[#3]

@SAMSAL Kudos to you.. it worked.. /\