The reader will read the file and create an application message. Then to process the message it is routed vie the Routing Rules. So you need to setup one routing rule per message type.
Routing rules has a condition to identify the message. It also has one (or many) Routing Addresses (Destination Address) connected to it. Routing Address defines what you want to do with the message.
Below example is routed on reader and file name. You can also write ”PREFIX*.json” for example. Only one wildcard (*) is allowed.
Part 2 is that you want to update a STD entity. The only way I see is that you create a JSON file and then created the Routing Address towards a STD Rest API by having the transport connector Projection.
However doing inbound integrations nowadays mostly does not use files. Instead other systems or integration platforms calls IFS Rest API’s directly via https.
There are limitations on size and timeouts when you use IFS Connect so you can’t have extremely large messages.