ABAP RESTful Application Programming Model (RAP) provides a framework for creating efficient, end-to-end solutions that are optimized for SAP HANA. It simplifies the development of OData services used in Fiori applications as well as Web APIs. This makes it easier for developers to build enterprise-ready and SAP HANA-optimized applications.
RAP is structured with three primary layers, each of these layers serves their own purpose. They consist of Data Modeling & Behaviour, Business Services Provisioning and lastly Service Consumption.
The first layer
The first layer Data Modeling & Behavior, forms the foundation of your application by defining its core business logic and data structure. It starts with Core Data Services (CDS), which are used to model the data and shape how it will be used within an application. Behaviour Definition (BDEF) is used to specify how the data should behave – for example, how will records be created, updated or deleted. In order to implement this behaviour we make use of ABAP and this enables us to turn these definitions into working logic. This layer also takes care of queries, by using CDS views to make data retrieval smooth and efficient.
The second layer
The second layer, the Business Services Provisioning layer, is where data and business logic are made available for use by other applications or services. It begins with Business Object Projection, which creates views that tailor the data to fit the needs of the consumer. CDS Projection Views then simplify and filter the data, ensuring that only the most relevant information is shared. BDEF (Behavior Projection) managed the behavior of these views, giving precise control over what actions can be performed and ensuring the right business rules are applied.
In order to make data and actions available as a service we make use of Service Definitions. Service Definitions sets restrictions on data by specifying which entities, fields or operations can be accessed by external systems or users. Service Binding is used to connect a Service Definition to a protocol for example OData v4 or OData v2.
The third layer
The third layer Service consumption is used to access the service that has been exposed in the underlying layers. This layer consists of two part, SAP Fiori Ui and Web API. Service from a RAP application can be consumed directly within a Fiori application. Services can also be accessed through Web APIs, which allows for integration with third party applications.
What makes RAP so powerful?
A Model-Driven approach is used by RAP, which simplifies the development of an application by making use of Core Data Services, Behaviour models and Service Generations. By making use of the backend of RAP and seamless integration with Fiori, applications can quickly be developer by developers.
RAP is considered to be highly flexible when it comes to deployment as it supports hybrid, cloud and on-premise environments. This allows businesses to take advantage of cloud scalability and still supporting their on-premise systems.
Another one of the standout features of RAP is that it allows you to extend and customize applications without changing the core of the SAP system. This complies with SAP’s Clean Core philosophy as developers can add custom logic, validations and business rules without touching the core SAP system.
RAP applications come with built-in security features that align with SAP’s best practices and compliance standards. By default, RAP ensures that your applications are secure, safeguarding sensitive data and helping businesses meet security and regulatory requirements without extra effort. This means you can trust that your applications are protected from the ground up, making security a seamless part of your development process.
Conclusion
SAP ABAP RAP is a powerful tool that simplifies the process of building applications. By organizing everything into three straightforward layers: Data Modeling & Behavior, Business Service Provisioning, and Service Consumption. This will help developers create scalable, efficient solutions without unnecessary complexity.
What makes RAP stand out is how easy it is to use and how flexible it is. Whether you’re building applications for the cloud, on-premise, or a mix of both, RAP has you covered.
