A lot has been written about exchanging data with REST APIs as it seems most modern APIs prefer to accept JSON as the preferred format. Nevertheless often developers are at the mercy of the API they are communicating with as was the case for a recent project I did for the River of Time Museum in Fountain Hills, Arizona.
This blog post is kind of specific but for anyone who needs assistance connecting their e-commerce application to QuickBooks Legacy QBMS Payments API where JSON is not supported, I hope it helps.