Came here via Google. Just for other people. NiFi does support multipart with the InvokeHTTP since a few releases: https://palindromicity.blogspot.com/2020/04/sending-multipart-form-data-with.html ... View more

This is slightly confusing, but if you have a Mysql query to generate the difference, then Nifi can get the data from there and convert to XML if needed.    As generating the difference seems to be the main challenge here, perhaps start by finding a way to do this, and from here it should be trivial to design the Nifi flow around this.   ---- If this answers the question, consider marking this as the answer  ... View more