I did set-up a successful RestAPI data source to retrieve data to a PowerBI Desktop dashboard but not an expert on PowerBI (learn it as I go mostly) and work on it when I have spare time which is rare, so progress is extremely slow. I can tell you, however, that it is possible! The conversion from XML/JSON (latter is certainly easier) is a bit PIA but it can be done. It’s not officially documented anywhere but here is a snippet of how I got it to work (you can see the data-source definition with the session relevance query) and then the data transformation steps afterwards. A quick tip about the data source - standard “Get Data” -> Web but then had to edit the default connection in Power Query Editor and fix the actual code of the connection/calls it was making to get it in JSON format back via URI-parameter and get it to work how I want it (the default wizards in PowerBI tend to add a lot of “fluff” that makes it more complex than it needs to imho but again, it may be me being not very good at it).
