I have JSON messages in the flowfiles, and I'm putting a subset of the JSON elements into attributes using EvaluateJSONPath.   The issue is that when I use AttributesToJSON, all the elements get wrapped in quotes, so the JSON fields that are/were arrays now are just strings that happen to have square brackets in them, and quotes around the strings in the array are escaped.   How do I preserve the "non-stringiness" of my JSON through these operations?

Input JSON:

{"customer_id": 1234567, "vckey_list": ["test value"]}

I pull both of those fields into attributes using EvaluateJSONPath, and then user AttributesToJSON with content-flowfile and this is the output.   Obviously the strings within the array are escaped because the array itself is quoted, as is the thing that was a number.

Output JSON after 2 operations:

{"customer_id": "1234567", "vckey_list": "[\"test value\"]"}

My desired output would be identical to the original.  

{"customer_id": 1234567, "vckey_list": ["test value"]}

I'm sure I've missed something simple to make these operations commute.