Need an Expert on REST-API - Running application and database locally

  1. UI is screwy for me - can never see the results of a data test so I have embedded the notepad error.

  2. My database is behind a corporate firewall and will never be exposed to the internet. My development environment is on the same vlan as the database. Using a swagger tool, I can confirm the connections are working. I can access my swagger tool on my iPhone when it is also connected to the same vlan.

How do I preview my iPhone McGyver application with data behind a fireware? Should it be possible?

The SAP Build Apps Composer is on the public internet.
Thus you will need to create a public internet facing API proxy towards your on-premise database and your on-premise API.

One of such tools is the SAP API Management as it would allow to create an API proxy with your swagger definition over an API Provider towards your on premise world.