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

Development of information system for digital dialogue in teaching using RESTful service

This study was supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia, and these results are parts of the Grant No. 451-03-68/2022-14/200132 with University of Kragujevac – Faculty of Technical Sciences Čačak.Digital dialogue in teaching, as an asymmetric, multi-user communication system, represents an indirect connection between teachers and students in real time. For this type of communication, it is necessary to ensure the fastest response of clients and to ensure parallel processing as well. The features of RESTful web service, such as: possibility of caching, uniform interface and explicit use of HTTP methods, recommends it as a key component in the information system for digital dialogue in teaching. This paper presents a project for development of such information system using RESTful web service and a description of its advantages compared to other solutions.Publishe

Measuring the understandability of WSDL specifications, web service understanding degree approach and system

Web Services (WS) are fundamental software artifacts for building service oriented applications and they are usually reused by others. Therefore they must be analyzed and comprehended for maintenance tasks: identification of critical parts, bug fixing, adaptation and improvement. In this article, WSDLUD a method aimed at measuring a priori the understanding degree (UD) of WSDL (Web Service Description Language) descriptions is presented. In order to compute UD several criteria useful to measure the understanding’s complexity of WSDL descriptions must be defined. These criteria are used by LSP (Logic Scoring of Preference), a multicriteria evaluation method, for producing a Global Preference value that indicates the satisfaction level of the WSDL description regarding the evaluation focus, in this case, the understanding degree. All the criteria information required by LSP is extracted from WSDL descriptions by using static analysis techniques and processed by specific algorithms which allow gathering semantic information. This process allows to obtain a priori information about the comprehension difficulty which proves our research hypotheses that states that it is possible to compute the understanding degree of a WSDL description.info:eu-repo/semantics/publishedVersio

DESIGNING A FRAMEWORK FOR RESTFUL MULTI-AGENT SYSTEMS

Nowadays there are many systems that require some degree of automation. To attain this automation, agent technology has generally been found to be a promising approach. An agent is a piece of software that does activities on behalf of a user or another program. However, designing and deploying an agent infrastructure that achieves scalability is still a major challenge. In this thesis, a pattern for designing agents following RESTful principles is proposed in an effort to address the aforementioned challenges. In addition, the pattern will follow the FIPA Abstract Architecture; which is aimed at developing intelligent agents and supporting interoperability among agents and agent-based systems. Furthermore, an evaluation is done to investigate the scalability of the deployment of a RESTful multi-agent system

Do RESTful API Design Rules Have an Impact on the Understandability of Web APIs? A Web-Based Experiment with API Descriptions

Context: Web APIs are one of the most used ways to expose application functionality on the Web, and their understandability is important for efficiently using the provided resources. While many API design rules exist, empirical evidence for the effectiveness of most rules is lacking. Objective: We therefore wanted to study 1) the impact of RESTful API design rules on understandability, 2) if rule violations are also perceived as more difficult to understand, and 3) if demographic attributes like REST-related experience have an influence on this. Method: We conducted a controlled Web-based experiment with 105 participants, from both industry and academia and with different levels of experience. Based on a hybrid between a crossover and a between-subjects design, we studied 12 design rules using API snippets in two complementary versions: one that adhered to a "rule" and one that was a "violation" of this rule. Participants answered comprehension questions and rated the perceived difficulty. Results: For 11 of the 12 rules, we found that "violation" performed significantly worse than "rule" for the comprehension tasks. Regarding the subjective ratings, we found significant differences for 9 of the 12 rules, meaning that most violations were subjectively rated as more difficult to understand. Demographics played no role in the comprehension performance for "violation". Conclusions: Our results provide first empirical evidence for the importance of following design rules to improve the understandability of Web APIs, which is important for researchers, practitioners, and educators.Comment: Currently under review at Empirical Software Engineering (EMSE

RESTful Web Services Development with a Model-Driven Engineering Approach

A RESTful web service implementation requires following the constrains inherent to Representational State Transfer (REST) architectural style, which, being a non-trivial task, often leads to solutions that do not fulfill those requirements properly. Model-driven techniques have been proposed to improve the development of complex applications. In model-driven software development, software is not implemented manually based on informal descriptions, but partial or completely generated from formal models derived from metamodels. A model driven approach, materialized in a domain specific language that integrates the OpenAPI specification, an emerging standard for describing REST services, allows developers to use a design first approach in the web service development process, focusing in the definition of resources and their relationships, leaving the repetitive code production process to the automation provided by model-driven engineering techniques. This also allows to shift the creative coding process to the resolution of the complex business rules, instead of the tiresome and error-prone create, read, update, and delete operations. The code generation process covers the web service flow, from the establishment and exposure of the endpoints to the definition of database tables.A implementação de serviços web RESTful requer que as restrições inerentes ao estilo arquitetónico “Representational State Transfer” (REST) sejam cumpridas, o que, sendo usualmente uma tarefa não trivial, geralmente leva a soluções que não atendem a esses requisitos adequadamente. Técnicas orientadas a modelos têm sido propostas para melhorar o desenvolvimento de aplicações complexas. No desenvolvimento de software orientado a modelos, o software não é implementado manualmente com base em descrições informais, mas parcial ou completamente gerado a partir de modelos formais derivados de meta-modelos. Uma abordagem orientada a modelos, materializada através de uma linguagem específica do domínio que integra a especificação OpenAPI, um padrão emergente para descrever serviços REST, permite aos desenvolvedores usar uma primeira abordagem de design no processo de desenvolvimento de serviços da Web, concentrando-se na definição dos recursos e das suas relações, deixando o processo de produção de código repetitivo para a automação fornecida por técnicas de engenharia orientadas a modelos. Isso também permite focar o processo de codificação criativo na resolução e implementação das regras de negócios mais complexas, em vez de nas operações mais repetitivas e propensas a erros: criação, leitura, atualização e remoção de dados. O processo de geração de código abrange o fluxo do serviço web desde o estabelecimento e exposição dos caminhos para os serviços disponíveis até à definição de tabelas de base de dados

A comprehensive evaluation framework for system modernization : a case study using data services

Modernization is a solution to migrate cumbersome existing systems to a new architecture for improved longevity of business processes. Three modernization approaches exist. White-box and black-box modernization are distinct from one another. Grey-box modernization is a hybrid of the white-box and black-box approaches. Modernization can be utilised to create data services for a Service Oriented Architecture. Since it is unclear which modernization approach is more suitable for the development of data services, a comprehensive evaluation framework is proposed to evaluate which of the white- or black-box approaches is more suitable. The comprehensive framework consists of three evaluation components. Firstly, developer effort to modernize existing code is measured by acknowledged software metrics. Secondly, the quality of the data services is measured against identified Quality of Service criteria for data services in particular. Thirdly, the effectiveness of the modernized data services is measured through usability evaluations. By inspection of the combination of application of each of the evaluation components, a recommended approach is identified for the modernization of data services. The comprehensive framework was successfully employed to compare the white-box and black-box modernization approaches applied to a case study. Results indicated that had only a single evaluation component been used, inconclusive results of the more suitable approach may have been obtained. The findings of this research contribute a comprehensive evaluation framework which can be applied to compare modernization approaches and measure modernization success

A comprehensive evaluation framework for system modernization : a case study using data services

Modernization is a solution to migrate cumbersome existing systems to a new architecture for improved longevity of business processes. Three modernization approaches exist. White-box and black-box modernization are distinct from one another. Grey-box modernization is a hybrid of the white-box and black-box approaches. Modernization can be utilised to create data services for a Service Oriented Architecture. Since it is unclear which modernization approach is more suitable for the development of data services, a comprehensive evaluation framework is proposed to evaluate which of the white- or black-box approaches is more suitable. The comprehensive framework consists of three evaluation components. Firstly, developer effort to modernize existing code is measured by acknowledged software metrics. Secondly, the quality of the data services is measured against identified Quality of Service criteria for data services in particular. Thirdly, the effectiveness of the modernized data services is measured through usability evaluations. By inspection of the combination of application of each of the evaluation components, a recommended approach is identified for the modernization of data services. The comprehensive framework was successfully employed to compare the white-box and black-box modernization approaches applied to a case study. Results indicated that had only a single evaluation component been used, inconclusive results of the more suitable approach may have been obtained. The findings of this research contribute a comprehensive evaluation framework which can be applied to compare modernization approaches and measure modernization success