A SOA Repository with Advanced Analysis Capabilities - Improving the Maintenance and Flexibility of Service-Oriented Applications

a service-oriented architecture (SOA), a change or shutdown of a particular service might have a significant impact on its consumers (e.g., IT systems). To effectively cope with such situations, the IT systems affected by a service change should be identified before actually applying the latter. For this purpose, a SOA repository with advanced analysis capabilities is needed. However, due to the numerous complex inter-dependencies between service providers and consumers, it is a challenging task to figure out which IT systems might be directly or indirectly affected by a service change and for which period of time this applies. The paper tackles this challenge and presents the design of an advanced SOA repository enriched with analysis capabilities. In particular, this repository enables automatic analyses to detect already existing problems (as-is analyses) as well as problems that might occur due to future service changes (what-if analyses). Respective analyses will foster the development of robust service-oriented applications

Erhöhung der System-Stabilität und -Flexibilität durch ein SOA-Repository mit Analysefähigkeiten

In einer Service-orientierten Architektur (SOA) werden bereitgestellte Services von Servicenutzern, etwa fremden IT-Systemen, konsumiert. Eine Serviceänderung bzw. -abschaltung kann solche Servicenutzer schwer beeinträchtigen. Deshalb müssen diese vor einem solchen Eingriff ermittelt werden, wozu das SOA-Repository genutzt werden kann. Allerdings ist bei umfangreichen SOA-Repositories schwer erkennbar, welche IT-Systeme (evtl. indirekt) in welchem Zeitraum betroffen sein werden. Da diese Problemstellung in der bisherigen SOA-Literatur nicht betrachtet wird, stellen wir ein Lösungskonzept vor. Es ermöglicht automatisierte Analysen, um in den Daten enthaltene Problemsituationen identifizieren zu können (Ist- Analysen), und auch um Auswirkungen zukünftig durchzuführender Serviceänderungen zu simulieren (Planspiele)

Scenario-based modifiability evaluation of service-based systems : tool support for lightweight scenario templates

In modern software development, modifiability has arguably become one of the most important software quality attributes. There has been extensive research on the topic of the evaluation of a system's or architecture's ability to be modified. Scenario-based methods such as ALMA or SAAM have been around for a long time, and have proven to be effective ways to evaluate software. However, these methods are usually quite expensive in terms of time and require a big part of a project's stakeholders to align. One thing there has been a notable lack of is the modifiability evaluation specifically of systems using a service-based architecture. Properties of this architectural style can be useful to make more efficient assessments of a software's modifiability. This work seeks to propose a method to evaluate modifiability of service-based systems using a scenario-based analysis approach. Special emphasis is placed on this method being lightweight, i.e. less time-consuming and more flexible than similar methods. To achieve this, existing works on the topics of scenario-based software evaluation and the evolution of service-based systems were studied. Based on the acquired knowledge, a model of software change and an approach to analyze a system’s modifiability utilizing this model was designed. A tool was created to support our proposed method. Testing and applying the tool leads to iterative adjustments to the method. To demonstrate the insights that can be won using this method as well as how it is used, we perform an example application of it. The result of this work is a method that exchanges some of the reliability and accuracy of other scenario-based methods for flexibility and brevity. While the method achieves its goal of being lightweight, real-world testing and validation may lead to improvements to it

Exploring and categorizing maintainability assurance research for service and microservice-based systems

Im Laufe des Softwarelebenszyklus eines Programms innerhalb einer sich ständig wechselnden Softwareumgebung ist es wahrscheinlich, dass dieses Programm regelmäßig gewartet werden muss. Wartungen kosten Geld und somit ist es wichtig, dass ebensolche Wartungen effizient und effektiv durchgeführt werden können. Im Laufe der Geschichte der Softwareentwicklung traten unter anderem zwei Architekturmuster hervor: Serviceorientierte Architektur und Microservices. Da diese Architekturmuster ein hohes Maß an Wartbarkeit versprechen, wurden viele Altsysteme hin zu diesen modernen Architekturen migriert. Es kann fatale Folgen für Unternehmen haben, wenn Änderungen an einem System nicht schnell, risikofrei und fehlerfrei umgesetzt werden können. Es wurden bereits viele Forschungsarbeiten bezogen auf die Wartbarkeit von serviceorientierter Architektur publiziert. Systeme basierend auf Microservices fanden jedoch, bezogen auf Wartbarkeitssicherung, nicht viel Beachtung. Sämtliche Forschungsarbeiten befinden sich verteilt auf viele Literaturdatenbanken, wodurch ein umfassender Überblick erschwert wird. Um einen solchen Überblick bereitzustellen, führten wir im Rahmen dieser Bachelorarbeit eine systematische Literaturstudie durch, die sich mit der Wartbarkeitssicherung von serviceorienter Architektur und Systemen basierend auf Microservices beschäftigt. Zur Durchführung dieser systematischen Literaturstudie entwickelten wir eine Reihe von relevanten Forschungsfragen sowie ein striktes Forschungsprotokoll. Aufbauend auf diesem Protokoll sammelten wir insgesamt 223 Forschungsarbeiten von verschiedenen Herausgebern. Diese Arbeiten wurden bezüglich ihres Inhalts zuerst in drei Gruppen von Kategorien unterteilt (architektonisch, thematisch und methodisch). Danach wurden die jeweils relevantesten Forschungsrichtungen aus jeder thematischen Kategorie herausgearbeitet und vorgestellt. Zum Abschluss wurden deutliche Unterschiede der in den Forschungsarbeiten präsentierten Inhalte in Bezug auf serviceorientierte Architektur und Microservice-basierte Systeme herausgearbeitet und dargestellt. Unsere Ergebnisse zeigten eine deutliche Unterrepräsentation von Forschungsarbeiten zur Wartbarkeitssicherung für Microservice-basierte Systeme. Während der Untersuchung der Kategorien konnten wir diverse Forschungsrichtungen innerhalb dieser feststellen. Ein Beispiel hierfür ist die Forschungsrichtung "change impact in business processes" in der Kategorie "Change Impact and Scenarios". Abschließend konnten wir einige Unterschiede bezogen auf die gesammelten Forschungsarbeiten zwischen Systemen basierend auf einer serviceorientierten Architektur und Systemen basierend auf Microservices feststellen. Ein solcher Unterschied kann zum Beispiel in der Kategorie "Antipatterns and Bad Smells" gefunden werden. Im Vergleich zu Forschungsarbeiten, welche sich auf serviceorientierte Architektur beziehen, beinhalten Forschungsarbeiten im Zusammenhang mit Systemen auf Basis von Microservices nur grundlegende Informationen zu Antipatterns, jedoch keine Herangehensweisen, um diese zu erkennen. Aufgrund unserer Ergebnisse schlagen wir einen stärkeren Fokus auf Forschung zur Wartbarkeitssicherung in Microservice-basierten Systemen vor. Mögliche zukünftige Forschungsarbeiten könnten überprüfen, ob Herangehensweisen zur Wartbarkeitssicherung von serviceorientierter Architektur auch bei Microservices anwendbar sind. Darüber hinaus schlagen wir die Durchführung von systematischen Literaturstudien vor, welche Themen wie "runtime adaptation", "testing" und "legacy migration" untersuchen, da diese Themen in unserer Literaturstudie ausgeschlossen wurden.It is very likely that software running in an everchanging environment needs to evolve at multiple points during its lifecycle. Because maintenance costs money, it is important for such tasks to be as effective and efficient as possible. During the history of software development service- and microservice-based architectures have emerged among other architectures. Since these architectures promise to provide a high maintainability, many legacy systems are or were migrated towards a service- or microservice-based architecture. In order to keep such systems running, maintenance is inevitable. While a lot of research has been published regarding maintainability assurance for service-based systems, microservice-based systems have not gotten a lot of attention. All published research is spread across several scientific databases which makes it difficult to get an extensive overview of existing work. In order to provide such overview of maintainability assurance regarding service- and microservice-based systems, we conducted a systematic literature review. To support our literature review, we developed a set of meaningful research questions and a rigid research protocol. Based on our protocol we collected a set of 223 different papers. These papers were first categorized into a threefold set of categories (architectural, thematical and methodical). After that, the most relevant research directions from each thematical category were extracted and presented. Lastly, we extracted and presented notable differences between approaches relating to service-oriented architecture or microservice-based systems. Our findings show a clear underrepresentation of maintainability assurance approaches suitable for microservice-based systems. We further discovered that regarding our formed categories, we could find several research directions such as change impact in business processes in "Change Impact and Scenarios". In the end, we could identify some differences between service- and microservice-based systems concerning approaches we retrieved in this thesis. A difference, for example was that in comparison with papers related to service-oriented architecture in "Antipatterns and Bad Smells", microservices related papers only contained basic information on antipatterns, but no approaches to detect them. Due to our findings we suggest a higher participation in research regarding maintainability assurance for microservice-based systems. Possible future work in this area could include further research on the applicability of service-oriented maintainability assurance approaches or techniques in microservice-based systems. Furthermore, future researchers could conduct follow-up literature reviews and investigate topics such as runtime adaptation, testing and legacy migration, since we excluded such topics from this thesis

Impact analysis of enterprise resource planning post-implementation modifications

Enterprise Resource Planning (ERP) as business system integration evolves in the post-implementation phase due to the change in business requirements caused by competitive environments. Uncontrolled or poorly managed changes may lead to low quality, chaotic systems and data that are difficult to use and maintain. Constructivist approaches to effectively manage post-implementation change in ERP systems from the design-related standpoint are currently lacking. Research in this field mostly focuses on CSF (Critical Success Factors) of the post-implementation phase rather than providing a well-structured approach for managing the changes. Thus, this thesis is designed to close this gap by devising methods and tools for controlled ERP post-implementation change management to support stakeholders, such as business analysts and developers, in assessing the impact of the modification. Our methodology draws a parallel approach between ERP post-implementation change management and traditional engineering change management in product design and proposes a framework for impact analysis of ERP post-implementation modifications. The framework defines a meta-model of the dependencies among ERP entities such as business processes, functions, and data. Based on the identified dependencies, the framework allows to automatically analyse the impact of a proposed change through a set of impact analysis mechanisms. Then, evaluate the scope and depth of a proposed change through a set of impact assessment metrics. As part of the evaluation process, our framework has been embedded in a software tool i.e. decision support system to demonstrate the feasibility of our approach. Then, provides an empirical study to validate the research method and the tool through a panel of ERP experts and end users. The result confirms that our framework provides scientifically grounded method to manage ERP post-implementation modification in a controlled manner. The application of our approach improved change impact analysis and reduced the risk associated with post-implementation change management in future

Change impact analysis for service based business processes

Change management is critical and challenging in the development and maintenance of service-based applications and information systems due to the distributed and dynamic nature of services. This paper proposes an approach for facilitating the change impact analysis in a service oriented environment. This research focuses on a typical scenario that multiple services are supported by a single business process. The change impact is analyzed based on the study of the dependency between services and business processes. Types of changes and change impact patterns are identified on the foundation of a service oriented business process model. These change types and the impact patterns can be used to enable the analysis of change propagation of the business process and associated services. Algorithms for computing impact scopes of changes are provided.8 page(s