Sebastian Wieczorek

Applying Model Checking to Generate Model-Based Integration Tests from Choreography Models

Choreography models describe the communication protocols between services. Testing of service choreographies is an important task for the quality assurance of service-based systems as used e.g. in the context of service-oriented architectures (SOA). The formal modeling of service choreographies enables a model-based integration testing (MBIT) approach. We present MBIT methods for our service choreography modeling approach called Message Choreography Models (MCM). For the model-based testing of service choreographies, MCMs are translated into Event-B models and used as input for our test generator which uses the model checker ProB.

Precise Steps for Choreography Modeling for SOA Validation and Verification

Service-oriented architecture (SOA) enables organizations to transform their existing IT infrastructure into a more flexible business process platform. In this architecture, decoupled components that provide standard services can be composed to form individually configured and highly flexible applications. When building such applications it is important to have a formal specification of the interaction protocols between the composed services not only because such a specification provides an accurate and unambiguous description of the interactions and their ordering but also to enable automated verification and validation. In this paper, we present a case study from the SAP context showing the interactions between two SAP service components and use that case study to derive a set of modeling requirements. This motivates a discussion about applicable techniques for service choreography modeling and whether existing choreography languages cover the identified needs.

MBT4Chor: A Model-Based Testing Approach for Service Choreographies

Service choreographies describe the global communication protocols between services and testing these choreographies is an important task in the context of service-oriented architectures (SOA). Formal modeling of service choreographies makes a model-based testing (MBT) approach feasible. In this paper we present an MBT approach for SOA integration testing based on SAP proprietary choreography models called Message Choreography Models (MCM). In our approach, MCMs are translated into executable UML models using Java as action language. These UML models are used by a UML model execution engine developed by IBM for test generation and model debugging. We describe the achievements and challenges of our approach based on first experimental evaluation conducted at SAP.

Test Data Provision for ERP Systems

Software development and testing of enterprise resource planning (ERP) systems demands dedicated methods to tackle its special features. As manual testing is not able to systematically test ERP systems due to the involved complexity, an effective testing approach should be automated, also requiring that the appropriate test data has to be provided alongside. In this paper we identify four main challenges regarding the provision of test data for automatic testing of ERP software: system test data supply, system test data stability, input test data constraints and test data correlation. Several possible solutions to these challenges are discussed. We conclude with an outlook to possible research activities.

Improving Testing of Enterprise Systems by Model-Based Testing on Graphical User Interfaces

Software development and testing of Enterprise Resource Planning (ERP) systems demands dedicated methods to tackle its special features. As manual testing is not able to systematically test ERP systems due to the involved complexity, an efficient testing approach should be automatic. Since the underlying business processes of enterprise systems are realized at the level of the user interface (UI), system level testing is the dominant testing approach. The recent architectural shift to service-based enterprise systems demands to apply blackbox testing techniques. Model-based testing is a method that enables a high degree of automation for black-box testing, but the current research and practice usually does not address the UI. In this paper we describe the state of the art and state of the practice in order to motivate further research activities in this area.

Viewpoints for modeling choreographies in service-oriented architectures

Component integration plays a decisive role in service-oriented architectures (SOAs). The technical implementation must faithfully reflect business and enterprise integration requirements. This implies a good understanding of the globally observable message choreography but also of how messages are handled by the involved components and by the SOA middleware. In this paper we present a solution to the problem of keeping global and local viewpoints in synchronization via a common message choreography metamodel. As main contribution we shape various interpretations of global choreographies, which were left unspecified in state-of-the-art choreography approaches. We have implemented a message choreography modeling (MCM) environment incorporating these contributions. MCM seamlessly complements existing models at SAP. We show how service integration experts, architects, and testers can benefit from our approach that enables model-based integration testing and model verification facilities.

Using the UML Testing Profile for Enterprise Service Choreographies

In this paper we present an approach of using model-driven technologies for testing of service component interactions. We report on an industrial experiment with a novel combination of existing UML standards, i.e., the UML Testing Profile (U2TP), in conjunction with proprietary domain specific languages (DSLs). Many model-based testing (MBT) approaches use the UML 2 standard, but very few of them use also U2TP. Moreover, in practice UML coexists with DSLs which makes the overall integration not easy. We present our experiences and challenges of a U2TP-enabled MBT approach for a DSL for enterprise service choreographies, which describe the communication protocols between service components. The proposed workflow directly translates choreographies into UML models augmented with U2TP stereotypes, which are further loaded into our FOKUS!MBT tool chain. The tool provides an implementation of the U2TP standalone meta-model along with test case and test data generators to describe a holistic test process within one dedicated meta-model for testing concerns.

Model-Driven Service Integration Testing - A Case Study

This paper presents a case study for the modeling and model-based testing (MBT) of enterprise service choreographies. Our proposed MBT approach uses proprietary models called Message Choreography Models (MCM) as test models. The case study illustrates how MCM-based service integration testing allows to formalize design decisions and enables full integration into an existing industrial test infrastructure by using the concepts of domain specific languages and model transformations. Further, the MBT tools integrated into the testing framework have been compared based on one concrete use case.

Message choreography modeling

Service-based applications are based on modern architectures that require careful design of interfaces and protocols to allow smooth integration of service components. These design artifacts are not only useful for implementation, but could also be used for the derivation of integration tests. In order to be applied in these different activities of the development process, they have to conform to existing requirements and other specifications at different architectural levels. In addition, their internal consistency has to be ensured. In this paper, we present an approach to service integration based on a domain-specific language for service choreographies. We first explain the motivation for our work by defining the industrial context that led to the definition of a domain-specific choreography language, called message choreography modeling (MCM). We then provide syntax and semantics for MCM, together with suitable methods for ensuring its consistency. Finally, we report on our experience in applying the described language in practice.

Service integration: A soft spot in the SOA testing stack

The concepts of Service Oriented Architectures (SOA) have manifested themselves as the next evolutionary step for software development and the industry is fast in adopting SOA. The gained freedom of combining loosely coupled services is countered by resulting challenges for testing. While current research is mainly focusing on the investigation of advanced SOA feature like semantic service retrieval and dynamic binding, industrial projects still face fundamental problems in assuring software quality of SOA applications. In this paper we describe the SOA testing stack and the different objectives of its layers. We further explain why traditional and currently discussed testing techniques alone are not sufficient to cover all relevant testing layers. The unique SOA challenges posed by message based communication are usually not considered in research and industry. Therefore we discuss them in more detail and give advice of how to address them in a holistic development process.