NiFi - CaptureChangeMySQL convert json to ["col_name": "col_value"] format - apache-nifi

Question

prolog
MySQL table name: ar_tmp has two columns id int and name int
to do
I execute sql
insert into ar_tmp (id, name) values (1, 4);
and CaptureChangeMySQL captures this CDC and flow-content like this
{
"type":"insert",
"timestamp":1550221517000,
"binlog_filename":"mysql-bin.013920",
"binlog_position":241518646,
"database":"platform_data",
"table_name":"ar_tmp",
"table_id":2899035,
"columns":[
{
"id":1,
"name":"id",
"column_type":4,
"value":1
},
{
"id":2,
"name":"name",
"column_type":4,
"value":4
},
{
"id":3,
"value":4
}
]
}
But I want the result in this format
{
"type":"insert",
"timestamp":1550221517000,
"binlog_filename":"mysql-bin.013920",
"binlog_position":241518646,
"database":"platform_data",
"table_name":"ar_tmp",
"table_id":2899035,
"columns":[
{
"id":1,
"name":4
}
]
}
or
{
"id":1,
"name":4
}
solution
It can be done by hard coding using jsonPath function
But maybe to 'hard' to do this because each column using the same code which making the processor redundance(say 50 columns). Worsely, it's danger when the column name changed.
Any ideas?

Answer 1

JoltTransformJSON can help you here.
Try it out here
Jolt Spec for your demo input json:
[
{
"operation": "shift",
"spec": {
"columns": {
"*": {
"value": "columns.#(1,name)"
}
},
"*": "&"
}
}
]
The result is:
{
"type" : "insert",
"timestamp" : 1550221517000,
"binlog_filename" : "mysql-bin.013920",
"binlog_position" : 241518646,
"database" : "platform_data",
"table_name" : "ar_tmp",
"table_id" : 2899035,
"columns" : {
"id" : 1,
"name" : 4
}
}