Issue with CSVRecordSetWriter in ConvertRecord Processor

[José Maria Vieira]

Hi there fellow Nifi users:

Today I was developing a flow to convert some Json files to CSV.
I tried using the ConvertRecord processor, which seemed to be the best option. 
However I got java objects instead of the expected values.
I think the cause of the issue, is the json has nested objects.
I'm not sure if there is a bug in the CSVRecordSetWriter implementation or if I 
am doing something wrong.
What do you think?



Sample Json I used:

{
  "values": [
    [
      1558994400000,
      "Malformed virtual protocol"
    ],
    [
      1558994400000,
      "Advance Message Queuing Protocol"
    ],
    [
      1558994400000,
      "BitTorrent"
    ]
  ]
}


ConvertRecord Result:
values
"[[Ljava.lang.Object;@195d9bda, [Ljava.lang.Object;@248d0236, 
[Ljava.lang.Object;@192b2034]"

All the best,
José Vieira