https://community.cloudera.com/t5/Support-Questions/Nifi-How-to-add-key-value-to-json/m-p/200912#M162927 <P>True, if you are just inserting a single new field at the top-level of a flat JSON doc, this should work fine. However you may want an optional newline between the array and the first object if the JSON is pretty printed. Also, would this work if you had a nested array of objects further down in the file? I guess you could put in a start-of-line into the regex, but if the JSON has weird whitespacing you may run into the same problem. I recommend JOLT in general because it handles that kind of thing, but if you know what your input JSON looks like, this solution is simple and works well. </P> Fri, 09 Jun 2017 02:45:32 GMT mburgess 2017-06-09T02:45:32Z