Marco Crasso

Easy web service discovery: A query-by-example approach

Web services have acquired enormous popularity among software developers. This popularity has motivated developers to publish a large number of Web service descriptions in UDDI registries. Although these registries provide search facilities, they are still rather difficult to use and often require service consumers to spend too much time manually browsing and selecting service descriptions. This paper presents a novel search method for Web services called WSQBE that aims at both easing query specification and assisting discoverers by returning a short and accurate list of candidate services. In contrast with previous approaches, WSQBE discovery process is based on an automatic search space reduction mechanism that makes this approach more efficient. Empirical evaluations of WSQBE search space reduction mechanism, retrieval performance, processing time and memory usage, using a registry with 391 service descriptions, are presented.

A Survey of Approaches to Web Service Discovery in Service-Oriented Architectures

Discovering services acquires importance as Service-Oriented Computing SOC becomes an adopted paradigm. SOCs most popular materializations, namely Web Services technologies, have different challenges related to service discovery and, in turn, many approaches have been proposed. As these approaches are different, one solution may be better than another according to certain requirements. In consequence, choosing a service discovery system is a hard task. To alleviate this task, this paper proposes eight criteria, based on the requirements for discovering services within common service-oriented environments, allowing the characterization of discovery systems. These criteria cover functional and non-functional aspects of approaches to service discovery. The results of the characterization of 22 contemporary approaches and potential research directions for the area are also shown.

Improving Web Service descriptions for effective service discovery

Service-Oriented Computing (SOC) is a new paradigm that replaces the traditional way to develop distributed software with a combination of discovery, engagement and reuse of third-party services. Web Service technologies are currently the most adopted alternative for implementing the SOC paradigm. However, Web Service discovery presents many challenges that, in the end, hinder service reuse. This paper reports frequent practices present in a body of public services that attempt to prevent the discovery of any service. In addition, we have studied how to solve the discoverability problems that these bad practices cause. Accordingly, this paper presents a novel catalog of eight Web Service discoverability anti-patterns. We conducted a comparative analysis of the retrieval effectiveness of three discovery systems by using the original body of Web Services versus their corrected version. This experiment shows that the removal of the identified anti-patterns eases the discovery process by allowing the employed discovery systems to rank more relevant services before non-relevant ones, with the same queries. Moreover, we conducted a survey to collect the opinions from 26 individuals about whether the improved descriptions are more intelligible than the original ones. This experiment provides more evidence of the importance of correcting the observed problems.

Automatically Detecting Opportunities for Web Service Descriptions Improvement

Mostly e-business and e-applications rely on the Service Oriented Computing paradigm and its most popular implementation, namely Web Services. When properly implemented and described, Web Services can be dynamically discovered and reused using Internet technologies, pushing interoperability to unprecedented levels. However, poorly described Web Services are rather difficult to be discovered, understood, and reused. This paper presents heuristics for automatically detecting common pitfalls that should be avoided when creating Web Service descriptions. Experimental results with ca. 400 real-world Web Services, empirically show the feasibility of the proposed heuristics.

Best practices for describing, consuming, and discovering web services: a comprehensive toolset

The service‐oriented computing (SOC) paradigm has recently gained a lot of attention in the software industry because SOC represents a novel and a fresh way of architecting distributed applications. SOC is usually materialized via web services, which allows developers to structure applications exposing a clear, public interface to their capabilities. Although conceptually and technologically mature, SOC still lacks adequate development support from a methodological point of view. In this paper, we present the EasySOC project, a set of guidelines to simplify the development of service‐oriented applications and services. EasySOC is a synthesized catalog of best SOC development practices that arise as a result of several years of research in fundamental Services Computing topics, that is, Web Service Description Language‐based technical specification, Web Service discovery, and Web Service outsourcing. In addition, we describe a materialization of the guidelines for the Java language, which has been implemented as a plug‐in for the Eclipse IDE. We believe that both the practical nature of the guidelines and the availability of this software that enforces them may help software practitioners to rapidly exploit our ideas for building real SOC applications. Copyright

EasySOC: Making web service outsourcing easier

Service-oriented computing has been widely recognized as a revolutionary paradigm for software development. Despite the important benefits this paradigm provides, current approaches for service-enabling applications still lead to high costs for outsourcing services with regard to two phases of the software life cycle. During the implementation phase, developers have to invest much effort into manually discovering services and then providing code to invoke them. Mostly, the outcome of the second task is software containing service-aware code, therefore it is more difficult to modify and to test during the maintenance phase. This paper describes EasySOC, an approach that aims to decrease the costs of creating and maintaining service-oriented applications. EasySOC combines text mining, machine learning, and best practices from component-based software development to allow developers to quickly discover and non-invasively invoke services. We evaluated the performance of the EasySOC discovery mechanism using 391 services. In addition, through a case study, we conducted a comparative analysis of the software technical quality achieved by employing EasySOC versus not using it.

Bottom-up and top-down COBOL system migration to Web Services: An experience report

Moving from mainframe systems to a service-oriented architecture (SOA) using Web services is an attractive but daunting task. The bottom-up or direct-migration approach enables the effective modernization of legacy systems to Web services. Conversely, bringing migration into fruition with the top-down or indirect-migration approach is more difficult, but it achieves better migration results. Employing both approaches on the same large enterprise system is uncommon, which leaves no room for comparison. This article describes the migration processes, costs, and outcomes of applying both approaches on a real Cobol system.

Query by example for web services

Web services have acquired enormous popularity among software developers and researchers due to the increasing levels of flexibility required by current distributed applications. However, service search facilities are still rather difficult to use. This paper presents WSQBE, a search method that aims at assisting service discoverers by generating a short list of candidate services and easing query specification. In contrast with previous approaches, WSQBE discovery process is based on a novel search space reduction mechanism. Experimental evaluations of our approach are also reported.

Best Practices for Describing, Consuming, and Discovering Web Services: A Comprehensive Toolset [Thomson ISI, IF JCR2012=1.008]

The service‐oriented computing (SOC) paradigm has recently gained a lot of attention in the software industry because SOC represents a novel and a fresh way of architecting distributed applications. SOC is usually materialized via web services, which allows developers to structure applications exposing a clear, public interface to their capabilities. Although conceptually and technologically mature, SOC still lacks adequate development support from a methodological point of view. In this paper, we present the EasySOC project, a set of guidelines to simplify the development of service‐oriented applications and services. EasySOC is a synthesized catalog of best SOC development practices that arise as a result of several years of research in fundamental Services Computing topics, that is, Web Service Description Language‐based technical specification, Web Service discovery, and Web Service outsourcing. In addition, we describe a materialization of the guidelines for the Java language, which has been implemented as a plug‐in for the Eclipse IDE. We believe that both the practical nature of the guidelines and the availability of this software that enforces them may help software practitioners to rapidly exploit our ideas for building real SOC applications. Copyright

Bottom-Up and Top-Down Cobol System Migration to Web Services

Moving from mainframe systems to a service-oriented architecture (SOA) using Web services is an attractive but daunting task. The bottom-up or direct-migration approach enables the effective modernization of legacy systems to Web services. Conversely, bringing migration into fruition with the top-down or indirect-migration approach is more difficult, but it achieves better migration results. Employing both approaches on the same large enterprise system is uncommon, which leaves no room for comparison. This article describes the migration processes, costs, and outcomes of applying both approaches on a real Cobol system.