Document Services as Restful service - SAP Cloud Platform

Hello Experts,

We are considering SAP Cloud Platform Document Services for Document Management.

Documents will be uploaded by different means such as - user will login to SAPUI5 application (on SAP Cloud Platform Portal) and upload the documents. And an SAP PI system from on-premise uploads documents to SAP Cloud Platform Document Service (as shown below in picture).

We need to develop API (or restful services in SAP Cloud Platform) and provide them to other parties to be used. Now the question is how do we develop restful services in SAP Cloud Platform and publish it? Should we also need to consider API management for service hosting?