Section 15.9. What does the future hold for creating enterprise services?

15.9. What does the future hold for creating enterprise services?

Web services, although simple and standardized, are not by themselves enough for building a robust, reliable SOA that meets enterprise-level needs. The problem is exacerbated by the fact that the staff who administer enterprise applications and the developers maintaining the corporate web site and creating web services are typically in two different groups.

What is needed is a cohesive blueprint for an SOA that provides integration with enterprise applications and is adaptable to constantly changing market conditions. To be service oriented really means to be process oriented. That's what ESA is all about. It's an architectural blueprint for an SOA that is fully standards based and provides business value, with services modeled from key business processes.

This section briefly explores the future of creating enterprise services. We'll start by digging into the conceptual details of SAP's architectural vision for ESA, concepts that are foundational to creating your own ESA adoption roadmap.

15.9.1. What are business objects?

ESA is built on business objects, described in Chapter 5. Business objects are unique, identifiable business entities. Examples of business objects include a sales order, a purchase order, and a business partner. A business object is a logical building block, composed of numerous data elements, some of which are, in turn, based on the UN/CEFACT standard for global data types, ensuring wide interoperability with customers and partners.

15.9.2. What are the steps one takes to develop enterprise services?

Development of enterprise services can be broken down into two categories: modeling and implementation, as shown in Figure 15-22. The first part, modeling, is completely platform and language independent.

Modeling starts with a business process. During process modeling, in which you use a high-level tool based on ARIS, you identify the business objects and services you will use. You then go to the Enterprise Services Repository where you model the business objects and the services. Once modeling is complete, you create the UI. If the UI does not behave as desired, you can go back to the Enterprise Services Repository and make some changes. The next step is to create the implementation on the backend system.

How will the process change from what we have today? For one thing, modeling becomes a more visual task. Today modeling relates primarily to data types; in the near future, visual modeling tools will be integrated into SAP NetWeaver.

Figure 15-22. Typical enterprise services development steps

Modeling occurs in the Enterprise Services Repository, using the Enterprise Services Builder, which is an enhancement of SAP NetWeaver XI's Integration Builder that is slated for an upcoming release. All business objects must be modeled in the Enterprise Services Repository. The data types, data structures, and interfaces described in the Enterprise Services Repository are based on XML standards, including XSD and XML namespaces. (In fact, this adherence to XML standards is evident in the outside-in approach to development available today and described earlier in this chapter.)

The process of creating enterprise services continues to evolve with SAP making the development process both simpler and more robust, providing the infrastructure needed for a scalable implementation of ESA.

In this chapter, we examined how to create services today using SAP NetWeaver, both from the inside out and from the outside in. At various points in this process, you can glimpse the principles of ESA at work: we've seen abstraction that hides the arcane details of XML from the developer, reuse of data types, and modeling as a development methodology. These tools and technologies help us to make ESA a reality, starting today. Nothing that you do today working toward ESA will be wasted effort. However, the next generation of tools will bring ESA even more into focus, helping you to create a full-blown ESA that enhances the agility of your business.