I am in a situation where we have a Feature Service that is not publicly available. Of course, this means that it is not possible to access it directly from JavaScript (and it is not desirable as well as it has some sensitive information).
Therefore, what I was thinking is that instead of our Web App connecting directly to the ArcGIS services, it would connect to our 'proxy / middleware / man in the middle' system, and this would in turn authenticate and query ArcGIS. This would also allow us to restrict any access to sensitive data while enriching the data through our data that lives somewhere else.
I have a gut feeling that this is completely wrong..and the way to do it is to create some publicly available space and do the enriching on ArcGIS itself. From a business case, this is the least desirable route.
Thanks!