Enhancing SOA Integration through Enterprise Services

Venky Shankararaman and Lum Eng Kit

School of Information Systems, Singapore Management University

Singapore, Republic of Singapore

Abstract. Service enabling packaged applications can provide greater

flexibility and agility to business processes and thus can enhance SOA

integration. In this paper we demonstrate using SAP tools a process driven

composite application namely, Web Sales Process that leverages “enterprise

services” from within the SAP ERP.

1 Introduction

A recent trend among packaged application vendors such as SAP and Oracle is the

“service enablement” of their applications through enterprise services. As a result of

this “service enablement”, a new trend in solution development has emerged namely

“Composite Applications”. Composition is an emerging approach to delivering

enterprise solutions by assembling functionality from prebuilt components. This is

analogous to getting a prefabricated house assembled rather than having it custom-

built. With the emergence of the composite application paradigm the emphasis is on

using model driven and pattern based tools to design and execute the composite

application through a graphical interface rather than writing code [1], [2].

In this paper we demonstrate using SAP tools, the use of enterprise services to

enable a process driven composite application. In Section 2, we define an enterprise

service. Section 3, describes the Web Sales Process. In Section 4 we then present the

composite application architecture for this process along with implementation details.

Section 5 presents some concluding remarks and future trends in this area.

2 Enterprise Services

An enterprise service is technically a standards based web service that has been

purposefully designed for reusability and relates to a business object within the

context of a business process. For example, “Create Purchase Order” is an enterprise

service that relates to the business object “Purchase Order” in the context of the

“Procurement Process” within an ERP. Therefore, an enterprise service typically

contains the “best practice” business logic for executing standard business functions.

This was traditionally available only through proprietary APIs such as BAPI

(Business Application Programming Interface). A BAPI is a proprietary API method

of SAP business object. In contrast to a BAPI, an enterprise service uses a web

Shankararaman V. and Eng Kit L..

Enhancing SOA Integration through Enterprise Services.

DOI: 10.5220/0003554600370040

In Proceedings of the International Joint Workshop on Information Value Management, Future Trends of Model-Driven Development, Recent Trends in

SOA Based Information Systems and Modelling and Simulation, Veriﬁcation and Validation (RTSOABIS-2011), pages 37-40

ISBN: 978-989-8425-60-7

 2011 SCITEPRESS (Science and Technology Publications, Lda.)

service based standard interface to access business objects such as “Purchase Order”,

“Sales Order”, etc. In the current project, we therefore leverage the enterprise services.

3 Web Sales Process

We describe the Web Sales Process for an automotive spare parts manufacturer.

Following is a description of this business process. Fig 1 shows the Web Sales

Process, also referred to as the process model using the BPMN standard notations [3].

Fig. 1. Web Sales Process.

The customer submits the order by filling an online form. The next activity in the

process is to verify the customer credit status.

This is achieved through the Credit Verification System (CVS). The CVS is a Java

application that exposes a web service. This web service takes in the Customer ID as

input and returns whether additional approval is required. The CVS uses some

business logic such as customer loyalty, customer account balance, etc. to determine

the credit worthiness.

If approval is required the process waits for the Sales Manager to approve the sales.

If no approval is required, availability of the product is checked by invoking the

‘Check Inventory” enterprise service in the ERP.

If sufficient quantity is available, the sales order is created by invoking the “Create

Sales Order” enterprise service in the ERP. If sufficient quantity is not available,

appropriate business rules are triggered to define re-order quantity. A purchase order is

then created by invoking the enterprise service “Create Purchase Order”. Depending on

the process sequence appropriate notifications are sent to the customer.

4 Web Sales Composite Application Layered Architecture

The Web Sales Process is implemented as a composite application using SAP

Netweaver Composition Environment 7.2. The composite application is divided into

five layers namely Portal, Process, User Interface (UI), Business Logic and Back End

Connectivity (see Fig 2). Table 1 summarizes the different layers along with the SAP

tools that were used for the implementation of each layer. For a detailed overview of

the different layers one can refer to [4].

Fig. 2. Web Sales Composite Application: Layers.

5 Concluding Remarks

Composite applications enable the creation, delivery and execution of enterprise

applications by leveraging existing functionality through service calls that are loosely

coupled to backend systems such as ERP through service-oriented interfaces. In a

process-based composite application, an individual step within a business process uses

the service call to invoke a specific functionality within a backend system. In future,

enterprise applications will be more modularized with functionality being exposed as

enterprise services. This will lead to more flexible and agile business processes that

will extend beyond one organization and thus paving the way for business network

transformation [5].

Customer Sales Manager

UI for Customer to

enter order

UI for Sales Manager to

approve/decline order

Check Inventory Create SO

Packaged Application (SAP ERP)

Web Sales Process

Portal Layer

Process Layer

UI Layer

Business Logic

Layer

Back End

Connectivity Layer

Re-Order Business Rules

UI for Customer to

view Notification

Business Rules to control

process flow

Create PO Verify Credit

CVS

Service Registry

Table 1. Layers and Tools for Web Sales Composite Application.

Layer Description SAP Tools

Portal This layer provides an interface for the roles to interact

with the process activities. This is achieved through the

portal interface that can provide a single point of access

for managing tasks for a role.

Universal

Work

List-SAP

Portal

Process In this layer, we define the following: Process activities

and the sequence in which they are executed, Roles that

perform the activities and Business Documents (Data)

that is used or generated by the process

Process

Composer

User Interface In this layer, we define the user interface for each

activity that has to be performed as part of the business

process. The user interface models developed are

compiled into General Modeling Language (GML) code

and then deployed. At runtime, the GML code of the

deployed models is interpreted by a runtime engine.

Visual

Composer

Business Logic This layer includes business logic defined through

business rules. In addition, this layer also supports the

definition of the rules to manage the flow of the process.

Rules

Composer

Service

Registry

This layer provides information about the enterprise

service which includes reference to the services’ relevant

WSDL metadata and the location of the callable service

endpoint.

Service

Registry

Back End

Connectivity

This layer provides the ability to make the back end

systems transparent to the composite application. Web

Services are the recommended technology for

connecting composite applications to back-end systems.

Enterprise

Services

References

1. M. Huvar, T. Falter, T.Fielder and A.Zubev. Developing Applications with Enterprise

SOA. SAP Press. 2009, pp.33-49.

2. J.Rauscher and V.Stiehl. The Developer’s Guide to SAP Netweaver Composition

Environment.SAP Press.2008.

3. Derek Miers and Stephen A.White. BPMN Modeling and Reference Guide. Future

Strategies Inc., Lighthouse Pt, FL. 2008.

4. Eng Kit Lum and Venky Shankararaman.Create a Process Driven Composite Application

with CE7.2-Introduction. SAP Community Network. 2010, http://www.sdn.sap.com.

5. Business Network Transformation: Strategies to Reconfigure Your Business Relationships

for Competitive Advantage edited by J.Word, Wiley, 2009.