Published: 22nd October 2012
DOI: 10.4204/EPTCS.98
ISSN: 2075-2180

EPTCS 98

Proceedings 8th International Workshop on
Automated Specification and Verification of Web Systems
Stockholm, Sweden, 16th July 2012

Edited by: Josep Silva and Francesco Tiezzi

Preface
Josep Silva and Francesco Tiezzi
A Language-based Approach to Autonomic Component Ensembles Programming
Rocco De Nicola
1
Reflective Web Services
José Luiz Fiadeiro
2
Automatic WSDL-guided Test Case Generation for PropEr Testing of Web Services
Leonidas Lampropoulos and Konstantinos Sagonas
3
Model Validation in Ontology Based Transformations
Jesús M. Almendros-Jiménez and Luis Iribarne
17
The Jasper Framework: Towards a Platform Independent, Formal Treatment of Web Programming
James Smith
31
Using the DOM Tree for Content Extraction
Sergio López, Josep Silva and David Insa
46
Adding Sessions to BPEL
Jonathan Michaux, Elie Najm and Alessandro Fantechi
60
Analyzing Consistency of Behavioral REST Web Service Interfaces
Irum Rauf, Ali Hanzala Khan and Ivan Porres
77

Preface

This volume contains the final and revised versions of the papers presented at the 8th International Workshop on Automated Specification and Verification of Web Systems (WWV 2012). The workshop was held in Stockholm, Sweden, on June 16, 2012, as part of DisCoTec 2012, the 7th International Federated Conference on Distributed Computing Techniques. Previous WWV workshops were held in Reykjavik (2011), Vienna (2010), Hagenberg (2009), Siena (2008), Venice (2007), Cyprus (2006), and Valencia (2005). Information about the workshop can be found at: http://users.dsic.upv.es/~jsilva/wwv2012/

WWV is a yearly workshop that aims at providing an interdisciplinary forum to facilitate the cross-fertilization and the advancement of hybrid methods that exploit concepts and tools drawn from Rule-based programming, Software engineering, Formal methods and Web-oriented research. WWV has a reputation for being a lively, friendly forum for presenting and discussing work in progress. The proceedings have been produced after the symposium to allow the authors to incorporate the feedback gathered during the event in the published papers.

All papers submitted to the workshop were reviewed by at least three Program Committee members or external referees. The Program Committee held an electronic discussion leading to the acceptance of all papers for presentation at the workshop. In addition to the presentation of the contributed papers, the scientific programme included the invited talks by two outstanding speakers: Rocco De Nicola (IMT - Institute for Advanced Studies Lucca, Italy) and Josè Luiz Fiadeiro (Royal Holloway, United Kingdom). We would like to thank them for having accepted our invitation.

We want to thank the Program Committee members, who worked diligently to produce high-quality reviews for the submitted papers, as well as all the external reviewers involved in the reviewing process. Many thanks to the authors of the submitted papers and to all workshop participants. Thanks also go to the steering committee members of WWV for their valuable advice. We are very grateful to the DisCoTec 2012 General Chair Jim Dowling (KTH, Sweden), the DisCoTec 2012 Workshops Chair Rui Oliveira (Universidade do Minho, Portugal), and the local organizers for the great job they did in preparing the event. We would also like to thank Andrei Voronkov for his excellent EasyChair system that automates many of the tasks involved in chairing a conference. Finally, we wish to thank the editorial board of the Electronic Proceedings in Theoretical Computer Science (EPTCS) for publishing these proceedings in their series.


Josep Silva and Francesco Tiezzi
WWV 2012 Program Chairs and Proceedings Editors
September 2012



WORKSHOP ORGANIZATION

Program Chairs

Josep Silva   (Universitat Politècnica de València, Spain)
Francesco Tiezzi   (IMT Advanced Studies Lucca, Italy)

Program Committee

Jesús Almendros   (Universidad de Almería, Spain)
Maria Alpuente   (Universitat Politècnica de València, Spain)
Demis Ballis   (University of Udine, Italy)
Daniela Da Cruz   (Universidade do Minho, Portugal)
Santiago Escobar   (Universitat Politècnica de València, Spain)
Moreno Falaschi   (University of Siena, Italy)
Temur Kutsia   (Johannes Kepler University Linz, Austria)
Massimo Marchiori   (University of Padova, Italy)
Elie Najm   (Telecom ParisTech, France)
Rosario Pugliese   (University of Florence, Italy)
Antònio Ravara   (Universidade Nova de Lisboa, Portugal)
Kostis Sagonas   (University of Uppsala, Sweden)
Emilio Tuosto   (University of Leicester, United Kingdom)

External Reviewers

Daniel Romero   (Universitat Politècnica de València, Spain)

A Language-based Approach to Autonomic Component Ensembles Programming

Rocco De Nicola (IMT Advanced Studies Lucca, Italy)

SCEL is a new language for modelling autonomic service components and their ensembles that we are designing within the EU-FET project ASCENS. It brings together various programming abstractions that permit directly representing aggregations, behaviours, knowledge and policies. Moreover SCEL permits naturally programming interaction, self-awareness, context-awareness and adaptation. It relies on solid semantics grounds that lay the basis for developing logics, tools and methodologies for formal reasoning both on individual components and on ensembles. In the talk we presented design principles, syntax and operational semantics of the language, then showed how a dialect can be defined by appropriately instantiating the features of the language we left open to deal with different application domains.


Reflective Web Services

José Luiz Fiadeiro (Royal Holloway, University of London, UK)

At the heart of service-oriented computing is the logical separation between the service need and the need-fulfillment mechanism, i.e., the provision of the service. On the one hand, the binding between the requester and the provider is deferred to run time and established at the instance level, i.e., each time the need for the service arises. On the other hand, the discovery, selection, and binding of a service are performed by the middleware and, therefore, do not need to be programmed. This raises important challenges in the way we model computation in global computers like the internet: computation in the context of service-oriented architectures transforms not only the states of the components that implement applications but also the configurations of those applications.

In this talk, we present a formal model for the process of dynamic reconfiguration of the applications that execute over service-oriented architectures. The model is reflective in the sense that sub-configurations (representing business activities) are typed with formal interfaces that identify the properties that are required of external services that the activity may need to procure, the state conditions that trigger the discovery of those services, and the quality-of-service constraints through which external services will be ranked and selected.