Adopting SAP Application Extension Methodology

This lesson introduces the SAP Application Extension Methodology and describes the different phases of the methodology. From the evaluation of the extension use case to the evaluation of the extension technology to the definition of the target extension solution, a structured approach to the development and implementation of extensions is presented.

This lesson provides an overview of the SAP Application Extension Methodology, which offers a structured approach to extending applications.

The SAP Application Extension Methodology provides customers and partners with a structured, technology-agnostic approach to defining a company-specific extension strategy.

If you are faced with complex challenges such as:

• Clean Core
• Cloud readiness
• Future-Proof Concepts

It is essential to develop an extension strategy for your company. The SAP Application Extension Methodology can support and guide you in this process.

Applying this methodology ensures that all project participants use the same terminology and quickly reach a common understanding of the use case and the solution to be developed. You will gain an overview of possible technical extension blocks and will be able to make an informed decision about the future extension architecture of your organization. You can define an extension framework that serves as a guide for internal architects and developers.

The SAP Application Extension Methodology is a three-phase cycle that is open to SAP and third party technologies.

You can either apply the methodology to a specific use case (start with phase 1) or use it to define your extension strategy and governance (start with phase 2).

Create a basic architecture assessment of all relevant systems and components within the scope of the extension project and use case.

Assess Extension Technology, the methodology introduces specific terms and concepts. This allows you to speak the same language and improve the common understanding of a possible solution.

In phase 2, you decided which extension task is best suited to fulfill your business requirements. Now, in phase 3, you make an informed decision about which technical extension building blocks are suitable for each extension task to solve your business use case.

In this phase, the specific use case for the extension is assessed to define the requirements and objectives.

In this phase, you lay the foundation for any use case of an extension application based on the business context and the requirements in a defined area. For example, a business function, or a domain. Consider the system context of the respective area.

The personas involved here are:

• Enterprise Architect
• Solution Architect
• Business User

1 Define System Context

Basic architecture assessment of the relevant systems and components as part of the extension project.

2. Define Business Context & Requirements

A brief description of the general business requirement and its scope for your use cases.

3. Define application Extension Use Case

Define a target scenario for solving your business requirement by creating a detailed description of the use cases.

ACME Corporation needs support in validating new business partners. Therefore, it purchases and uses a service offering from iCredible. John is an employee of iCredible. Every time a new business partner is added to ACME Corporation's SAP S/4HANA system, John wants to receive a notification. John could then check the details of the business partner.

John would check the registered office of the business partner and perform some background checks. As a next step, John would update the verification details. Once the details are verified, the business partner is activated in ACME Corporation's SAP S/4HANA system.

SAP Application Extension Methodology Phase 1

Concrete examples show how use cases can be assessed and documented to create a solid basis for the extension.

• Extensions must follow the clean core concept.
• Simple maintenance and use of standard software/services are preferred.
• Only internal employees of ACME Corporation are allowed to access the SAP S/4HANA system.

The following is the example use case in individual scenes. The more detailed and extensive the scenes are modeled, the better the subsequent steps and the understanding of the parties involved.

The following is the scene description as an activity diagram to better visualize the use case. The color coding of the components corresponds to the scenes.

This phase focuses on the selection of suitable technologies and tools to be used for the extension.

Understand extension styles, extension tasks and get an overview of possible technical extension building blocks. These help you to translate business requirements into technical requirements.

1. Find Extension Styles

Framework of the overall technology for the creation of extensions and structural extension tasks. Extension styles can be categorized in the three-tier architecture model:

• Presentation layer
• Application layer
• Data layer

2. Define Extension Tasks

Describe a technology-agnostic extension task to solve a specific part of your extension use case description. Extension tasks can be categorized into extension styles.

3. Map the Extension Tasks to Technology

The extension technology mapping outlines the relationship between extension tasks and technical extension building blocks. Extension tasks can be implemented by using one or more technical extension building blocks. Technical extension building blocks can be categorized into extension domains such as core solution extension domain and side-by-side extension domain.

SAP Application Extension Methodology Phase 2

Examples and best practices for assessing and selecting the right technologies.

the following image is a technology mapping of the extension tasks. For a better overview in an Activity diagram.

The colors of the components reflect the scenes. The colors of the extension tasks, the layers, are:

• Green: Presentation Tier
• Yellow: Application Tier
• Blue: Data Tier

First, let's look at the ACME (SAP S/4HANA) side. All the following extension tasks can be implemented with key user extensibility in an SAP S/4HANA. You only need to add an additional flag (custom field) to the standard API and also display this in the maintenance overview of the Business Partner API.

• D01 is executed automatically when a custom field is added.
• A08 is executed by configuration through the Event Framework of SAP S/4HANA on-Premise.

The effort on the part of ACME - SAP S/4HANA on-premise is low.

A full stack CAP implementation is selected for the realization of the validation logic. The front end is realized within the CAP app with SAP Fiori Elements. The persistence is realized with SAP HANA database on SAP BTP.

Event management on the SAP BTP is mapped through the event mesh. The forwarding of an e-mail to iCredible is realized through Cloud Integration (SAP Integration Suite).

The implementation effort on SAP BTP is optimized by using SAP BTP services.

In this phase, the final solution is designed and described in detail to ensure that all requirements are met.

1. Extension technology per extension task

For each extension task (from the previous phase), analyze and decide which technical extension building blocks are suitable.

2. Decision guidance assets

Use the decision guidance assets such as extensibility guides, SAP Discovery Center missions, use case patterns and reference architectures to select your technical extension building blocks.

3. Extension target solution

Develop a target solution for the extension, for example, in the form of a diagram. This is the preparation for your implementation.

A solution diagram is created after the technology mapping. Existing reference architectures that can be found in the Discovery Center can help with this.

• SAP Application Extension Methodology Phase 3
• SAP BTP Reference Architectures

Examples show how a target extension solution can be effectively defined and implemented.

The following is the solution diagram for the sample.

This lesson offers an overview of existing sources of reference architectures. These can be used as a guideline for designing and implementing extensions to existing architectures.