Difference between SAP CAP and SAP RAP

by Barry Allen | Jun 13, 2021 | ABAP RAP

Preface – This post is part of the SAP ABAP RAP series.

Table of Contents

Introduction

SAP has introduced various programming models helping the organizations via development of efficient applications that meets their business needs. Over time, with changing requirements and technologies, these programming models have evolved from DYNPRO and list programming models for SAP GUI based applications to WEB DYNPRO model for web-based applications and thereafter to SAP ABAP programming model for SAP Fiori.

While SAP ABAP programming model for SAP Fiori is a key advantage in terms of evolving landscape, flexibility and efficient modelling for SAP Fiori, SAP HANA; lacks certain criteria like simplicity and typed access to business entities which seems to be the basic need for application development. Here RAP, a new programming model by SAP, fills the gap.

SAP ABAP RAP provides the intrinsic approach to build SAP Fiori based applications that are optimized for S/4 HANA and can run over on-premise as well as on the cloud.

We have been writing codes in different languages (such as ABAP, CDS, UI5/FIori and OData) at different platform (SAP NetWeaver, SAP Editor, HANA Studio, and SAP Web IDE) to achieve CRUD operation on business data. These all have their own limitation such as source independent development, platform independent development, etc. To remove dependency on multiple platforms and to combine SAP and open-source tools at a single platform, SAP came with Cloud Application Programming Model.

What is SAP CAP?

SAP Cloud Application Programming Model, also known as SAP CAP is a frameworks of tools, languages and libraries (both open source and SAP tools and technologies) designed efficiently with SAP best practices to help developers to minimize coding efforts, develop reusable peace of codes in form of micro services and to focus on designing and implementing business/enterprise specific logics.

What is SAP ABAP RAP?

SAP ABAP RESTful Application Programming Model (RAP) was introduced by SAP Cloud Platform ABAP environment and is available with 1808 release and higher.

The RESTful Application Programming model is built on the top of the semantic data model (CDS) and the transactional services are exposed in behaviour definition and implementation in implementing behaviour class. It also allows adapting the existing applications to be modelled which is intended to be used over a long time. You can start from scratch (greenfield implementation) or you can reuse existing business logic (brownfield implementation).

One can develop the following end-to-end scenarios:

SAP Fiori service
Service consumption
Web APIs