Recently we've been migrating our manual printing workflows to custom printing services at our ArcGIS Server instance. Everything was fun and games until we stumbled upon some Layouts with more than one Map Frame pointing to different Maps. After some googling I find out that the ExportWebMap specification doesn't cover Layouts with multiple Map Frames, forcing us to name the desired one as
WEBMAP_MAP_FRAME. We are currently considering writing a more robust Printing Service that will generate its own
Web_Map_as_JSON parameters internally resulting in multiple PNGs for each Map Frame and later on binding it all together in a final PDF down the pipeline but... it seems VERY janky!
TL;DR: Is it possible to create a custom printing service for ArcGIS Server to print a Layout with more than one Map Frame pointing to different Map Services?
We are using ArcGIS Pro 2.7.3 and our Enterprise instances are running 10.7.1 and 10.8.1.