The existing python services in ArcToolbox will work with a feature-service, but not a mapservice. If you are working in webappbuilder with a pair of point-based mapservices, each with millions of points, what would be a good approach to do a spatial-join between two such layers? Let's say it is something like households and utility access points - not quite one-to-one, but both huge. These are mapservice layers in a corporate portal, not feature-services. I don't mind doing a little Python or javascript programming, but I am not certain what would work best in a webappbuilder environment. Thoughts?
