Migrating Integration from SOAP to REST : Can the Advantages of Migration Justify the Project?

This thesis investigates the functional and conceptual differences between SOAP-based and RESTful web services and their implications in the context of a real-world migration project. The primary research questions addressed are: • What are the key functional and conceptual differences between SOAP-based and RESTful web services? • How can SOAP-based and RESTful service clients be implemented into a general client? • Can developing a client to work with REST and SOAP be justified based on differences in performance and maintainability? The thesis begins with a literature review of the core principles and features of SOAP and REST, highlighting their strengths, weaknesses, and suitability for different use cases. A detailed comparison table is provided to summarize the key differences between the two web services. The thesis presents a case study of a migration project from Lemonsoft's web team, which involved adapting an existing integration to support SOAP-based and RESTful services. The project utilized design patterns and a general client implementation to achieve a unified solution compatible with both protocols. In terms of performance, the evaluation showed that the general client led to faster execution times and reduced memory usage, enhancing the overall system efficiency. Additionally, improvements in maintainability were achieved by simplifying the codebase, using design patterns and object factories, adopting an interface-driven design, and promoting collaborative code reviews. These enhancements have not only resulted in a better user experience but also minimized future resource demands and maintenance costs. In conclusion, this thesis provides valuable insights into the functional and conceptual differences between SOAP-based and RESTful web services, the challenges and best practices for implementing a general client, and the justification for resource usage in such a solution based on performance and maintainability improvements

WSMO-Lite and hRESTS: lightweight semantic annotations for Web services and RESTful APIs

Service-oriented computing has brought special attention to service description, especially in connection with semantic technologies. The expected proliferation of publicly accessible services can benefit greatly from tool support and automation, both of which are the focus of Semantic Web Service (SWS) frameworks that especially address service discovery, composition and execution. As the first SWS standard, in 2007 the World Wide Web Consortium produced a lightweight bottom-up specification called SAWSDL for adding semantic annotations to WSDL service descriptions. Building on SAWSDL, this article presents WSMO-Lite, a lightweight ontology of Web service semantics that distinguishes four semantic aspects of services: function, behavior, information model, and nonfunctional properties, which together form a basis for semantic automation. With the WSMO-Lite ontology, SAWSDL descriptions enable semantic automation beyond simple input/output matchmaking that is supported by SAWSDL itself. Further, to broaden the reach of WSMO-Lite and SAWSDL tools to the increasingly common RESTful services, the article adds hRESTS and MicroWSMO, two HTML microformats that mirror WSDL and SAWSDL in the documentation of RESTful services, enabling combining RESTful services with WSDL-based ones in a single semantic framework. To demonstrate the feasibility and versatility of this approach, the article presents common algorithms for Web service discovery and composition adapted to WSMO-Lite

Toward the Next Wave of Services: Linked Services for the Web of Data

It has often been argued that Web services would have a tremendous impact on the Web, as a core enabling technology supporting a highly efficient service-based economy at a global scale. However, despite the outstanding progress in the area we are still to witness the application of Web services in any significant numbers on the Web. In this paper, we analyse the state of the art highlighting the main reasons we believe have hampered their uptake. Based on this analysis, we further discuss about current trends and development within other fields such as the Semantic Web and Web 2.0 and argue that the recent evolution provides the missing ingredients that will lead to a new wave of services - Linked Services - that will ultimately witness a significant uptake on a Web scale. Throughout the presentation of this vision we outline the main principles that shall be underpinning the development of Linked Services and we illustrate how they can be implemented using a number of technologies and tools we have developed and are in the process of extending

iServe: a linked services publishing platform

Despite the potential of service-orientation and the efforts devoted so far, we are still to witness a significant uptake of service technologies outside of enterprise environments. A core reason for this limited uptake is the lack of appropriate publishing platforms able to deal with the existing heterogeneity in the service technologies landscape and able to provide expressive yet simple and ecient discovery mechanisms. In this paper we describe iServe, a novel and open platform for publishing services which aims to better support their discovery and use. It exposes service descriptions as linked data expressed in terms of a simple vocabulary for describing services of different kinds with annotations in diverse formalisms. In addition to describing iServe, this paper also highlights the set of principles behind iServe, which we believe are essential for other generic repositories of semantic information notably ontology repositories

From Cross-Organizational Business Process to Public Services

Service-oriented architectures promise flexible process integration in heterogeneous environments, particularly in cross organizational contexts. Therefore, a systematic approach for deriving service definitions from cross-organizational business processes is required. The paper at hand presents a structured, model driven approach that allows for cross-organizational integration with service-oriented concepts and technologies based on a cross-organizational business process. The resulting method is specified by means of a metamodel and a procedure model. Taking into account existing approaches in the research field, the paper focuses on the activities for the service design specification and the subsequent implementation of the public services. Feasibility of the method is shown by applying it in a Business-to-Government (B2G) real-world scenario, namely the collaboration between a consigning company and customs authorities according to the new European harmonized customs procedures

Resource Oriented Architecture and REST

In light of the emerging discussion on Resource Oriented Architectures (ROA) and REST technology platform as solutions for Spatial Data distributed Infrastructures, the aim of this document is capture Resource Oriented Architectures principles and assess the feasibility as well as the advantages of using such approach compared with Service Oriented Architectures (SOA). Although most of the comments are domain independent we will use the INSPIRE (and the OGC services) infrastructure that is currently based on a SOA as domain for the comparative analysis.JRC.H.6-Spatial data infrastructure

iSemServ : a framework for engineering intelligent semantic services

The need for modern enterprises and Web users to simply and rapidly develop and deliver platform-independent services to be accessed over the Web by the global community is growing. This is self-evident, when one considers the omnipresence of electronic services (e-services) on the Web. Accordingly, the Service-Oriented Architecture (SOA) is commonly considered as one of the de facto standards for the provisioning of heterogeneous business functionalities on the Web. As the basis for SOA, Web Services (WS) are commonly preferred, particularly because of their ability to facilitate the integration of heterogeneous systems. However, WS only focus on syntactic descriptions when describing the functional and behavioural aspects of services. This makes it a challenge for services to be automatically discovered, selected, composed, invoked, and executed – without any human intervention. Consequently, Semantic Web Services (SWS) are emerging to deal with such a challenge. SWS represent the convergence of Semantic Web (SW) and WS concepts, in order to enable Web services that can be automatically processed and understood by machines operating with limited or no user intervention. At present, research efforts within the SWS domain are mainly concentrated on semantic services automation aspects, such as discovery, matching, selection, composition, invocation, and execution. Moreover, extensive research has been conducted on the conceptual models and formal languages used in constructing semantic services. However, in terms of the engineering of semantic services, a number of challenges are still prevalent, as demonstrated by the lack of development and use of semantic services in real-world settings. The lack of development and use could be attributed to a number of challenges, such as complex semantic services enabling technologies, leading to a steep learning curve for service developers; lack of unified service platforms for guiding and supporting simple and rapid engineering of semantic services, and the limited integration of semantic technologies with mature service-oriented technologies. vi In addition, a combination of isolated software tools is normally used to engineer semantic services. This could, however, lead to undesirable consequences, such as prolonged service development times, high service development costs, lack of services re-use, and the lack of semantics interoperability, reliability, and re-usability. Furthermore, available software platforms do not support the creation of semantic services that are intelligent beyond the application of semantic descriptions, as envisaged for the next generation of services, where the connection of knowledge is of core importance. In addressing some of the challenges highlighted, this research study adopted a qualitative research approach with the main focus on conceptual modelling. The main contribution of this study is thus a framework called iSemServ to simplify and accelerate the process of engineering intelligent semantic services. The framework has been modelled and developed, based on the principles of simplicity, rapidity, and intelligence. The key contributions of the proposed framework are: (1) An end-to-end and unified approach of engineering intelligent semantic services, thereby enabling service engineers to use one platform to realize all the modules comprising such services; (2) proposal of a model-driven approach that enables the average and expert service engineers to focus on developing intelligent semantic services in a structured, extensible, and platform-independent manner. Thereby increasing developers’ productivity and minimizing development and maintenance costs; (3) complexity hiding through the exploitation of template and rule-based automatic code generators, supporting different service architectural styles and semantic models; and (4) intelligence wrapping of services at message and knowledge levels, for the purposes of automatically processing semantic service requests, responses and reasoning over domain ontologies and semantic descriptions by keeping user intervention at a minimum. The framework was designed by following a model-driven approach and implemented using the Eclipse platform. It was evaluated using practical use case scenarios, comparative analysis, and performance and scalability experiments. In conclusion, the iSemServ framework is considered appropriate for dealing with the complexities and restrictions involved in engineering intelligent semantic services, especially because the amount of time required to generate intelligent semantic vii services using the proposed framework is smaller compared with the time that the service engineer would need to manually generate all the different artefacts comprising an intelligent semantic service. Keywords: Intelligent semantic services, Web services, Ontologies, Intelligent agents, Service engineering, Model-driven techniques, iSemServ framework.ComputingD. Phil. (Computer science