Slicing-based debugging of web applications in rewriting logic

The pervasiveness of computing on the Internet has led to an explosive growth of Web applications that, together with their ever-increasing complexity, have turned their design and development in a major challenge. Unfortunately, the huge expansion of development and utilization of Web computation has not been paired by the development of methods, models and debugging tools to help the developer diagnose, quickly and easily, potential problems in a Web application. There is an urgent demand of analysis and verification facilities capable to prevent insecure software that could cause unavailability of systems or services, or provide access to private data or internal resources of a given organization. The main goal of this MSc thesis is to improve the debugging of Web applications by embedding novel analysis and verification techniques that rely on the program semantics. As a practical realization of the ideas, we use Web-TLR that is a verification engine for dynamic Web applications based on Rewrite Logic. We extend Web-TLR with a novel functionality that supports effective Web debugging for realistic Web applications involving complex execution traces. This functionality is based on a backward trace slicing technique that is based on dynamic labeling. In order to extend the class of programs covered by the debugging methodology we formalize a generalization of the slicer to Conditional Rewriting Logic theories, greatly simplifying the debugging task by providing a novel and sophisticated form of pattern matching.Frechina Navarro, F. (2011). Slicing-based debugging of web applications in rewriting logic. http://hdl.handle.net/10251/15637Archivo delegad

A Rewriting-based, Parameterized Exploration Scheme for the Dynamic Analysis of Complex Software Systems

Los sistemas software actuales son artefactos complejos cuyo comportamiento es a menudo extremadamente difícil de entender. Este hecho ha llevado al desarrollo de metodologías formales muy sofisticadas para el análisis, comprensión y depuración de programas. El análisis de trazas de ejecución consiste en la búsqueda dinámica de contenidos específicos dentro de las trazas de ejecución de un cierto programa. La búsqueda puede llevarse a cabo hacia adelante o hacia atrás. Si bien el análisis hacia adelante se traduce en una forma de análisis de impacto que identifica el alcance y las posibles consecuencias de los cambios en la entrada del programa, el análisis hacia atrás permite llevar a cabo un rastreo de la procedencia; es decir, muestra como (partes de) la salida del programa depende de (partes de) su entrada y ayuda a estimar qué dato de la entrada es necesario modificar para llevar a cabo un cambio en el resultado. En esta tesis se investiga una serie de metodologías de análisis de trazas que son especialmente adecuadas para el análisis de trazas de ejecución largas y complejas en la lógica de reescritura, que es un marco lógico y semántico especialmente adecuado para la formalización de sistemas altamente concurrentes. La primera parte de la tesis se centra en desarrollar una técnica de análisis de trazas hacia atrás que alcanza enormes reducciones en el tamaño de la traza. Esta metodología se basa en la fragmentación incremental y favorece un mejor análisis y depuración ya que la mayoría de las inspecciones, tediosas e irrelevantes, que se realizan rutinariamente en el diagnostico y la localización de errores se pueden eliminar de forma automática. Esta técnica se ilustra por medio de varios ejemplos que ejecutamos mediante el sistema iJulienne, una herramienta interactiva de fragmentación que hemos desarrollado y que implementa la técnica de análisis de trazas hacia atrás. En la segunda parte de la tesis se formaliza un sistema paramétrico, flexible y dinámico, para la exploración de computaciones en la lógica de reescritura. El esquema implementa un algoritmo de animación gen érico que permite la ejecución indeterminista de una teoría de reescritura condicional dada y que puede ser objeto de seguimiento mediante el uso de diferentes modalidades, incluyendo una ejecución gradual paso a paso y una fragmentación automática hacia adelante y/o hacia atrás, lo que reduce drásticamente el tamaño y la complejidad de las trazas bajo inspección y permite a los usuarios evaluar de forma aislada los efectos de una declaración o instrucción dada, el seguimiento de los efectos del cambio de la entrada, y obtener información sobre el comportamiento del programa (o mala conducta del mismo). Por otra parte, la fragmentación de la traza de ejecución puede identificar nuevas oportunidades de optimización del programa. Con esta metodología, un analista puede navegar, fragmentar, filtrar o buscar en la traza durante la ejecución del programa. El marco de análisis de trazas gen érico se ha implementado en el sistema Anima y describimos una profunda evaluación experimental de este que demuestra la utilidad del enfoque propuesto.Frechina Navarro, F. (2014). A Rewriting-based, Parameterized Exploration Scheme for the Dynamic Analysis of Complex Software Systems [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/44234TESI

Combining Runtime Checking and Slicing to Improve Maude Error Diagnosis

The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-319-23165-5_3This paper introduces the idea of using assertion checking for enhancing the dynamic slicing of Maude computation traces. Since trace slicing can greatly simplify the size and complexity of the analyzed traces, our methodology can be useful for improving the diagnosis of erroneous Maude programs. The proposed methodology is based on (i) a logical notation for specifying two types of user-defined assertions that are imposed on execution runs: functional assertions and system assertions; (ii) a runtime checking technique that dynamically tests the assertions and is provably safe in the sense that all errors flagged are definite violations of the specifications; and (iii) a mechanism based on equational least general generalization that automatically derives accurate criteria for slicing from falsified assertions.This work has been partially supported by the EU (FEDER) and the Spanish MINECO project ref. TIN2013-45732-C4-01 (DAMAS), and by Generalitat Valenciana ref. PROMETEOII/2015/013 (SmartLogic). F. Frechina was supported by FPU-ME grant AP2010-5681, and J. Sapiña was supported by FPI-UPV grant SP2013-0083.Alpuente Frasnedo, M.; Ballis, D.; Frechina Navarro, F.; Sapiña Sanchis, J. (2015). Combining Runtime Checking and Slicing to Improve Maude Error Diagnosis. En Logic, Rewriting, and Concurrency. Essays Dedicated to José Meseguer on the Occasion of His 65th Birthday. 72-96. https://doi.org/10.1007/978-3-319-23165-5_3S7296Alpuente, M., Ballis, D., Espert, J., Romero, D.: Backward trace slicing for rewriting logic theories. In: Bjørner, N., Sofronie-Stokkermans, V. (eds.) CADE 2011. LNCS, vol. 6803, pp. 34–48. Springer, Heidelberg (2011)Alpuente, M., Ballis, D., Frechina, F., Romero, D.: Backward trace slicing for conditional rewrite theories. In: Bjørner, N., Voronkov, A. (eds.) LPAR-18 2012. LNCS, vol. 7180, pp. 62–76. Springer, Heidelberg (2012)Alpuente, M., Ballis, D., Frechina, F., Romero, D.: Julienne: a trace slicer for conditional rewrite theories. In: Giannakopoulou, D., Méry, D. (eds.) FM 2012. LNCS, vol. 7436, pp. 28–32. Springer, Heidelberg (2012)Alpuente, M., Ballis, D., Frechina, F., Romero, D.: Using conditional trace slicing for improving Maude programs. Sci. Comput. Program. 80, Part B:385–415 (2014)Alpuente, M., Ballis, D., Frechina, F., Sapiña, J.: Slicing-based trace analysis of rewriting logic specifications with $$I$$ Julienne. In: Felleisen, M., Gardner, P. (eds.) ESOP 2013. LNCS, vol. 7792, pp. 121–124. Springer, Heidelberg (2013)Alpuente, M., Ballis, D., Frechina, F., Sapiña, J.: Inspecting rewriting logic computations (in a Parametric and Stepwise Way). In: Iida, S., Meseguer, J., Ogata, K. (eds.) Specification, Algebra, and Software. LNCS, vol. 8373, pp. 229–255. Springer, Heidelberg (2014)Alpuente, M., Ballis, D., Frechina, F., Sapiña, J.: Debugging Maude programs via runtime assertion checking and trace slicing. Technical report, Department of Computer Systems and Computation, Universitat Politècnica de València (2015). http://safe-tools.dsic.upv.es/abets/abets-tr.pdfAlpuente, M., Ballis, D., Frechina, F., Sapiña, J.: Exploring conditional rewriting logic computations. J. Symbolic Comput. 69, 3–39 (2015)Alpuente, M., Escobar, S., Espert, J., Meseguer, J.: A modular order-sorted equational generalization algorithm. Inf. Comput. 235, 98–136 (2014)Baader, F., Snyder, W.: Unification Theory. In: Robinson, J.A., Voronkov, A. (eds.) Handbook of Automated Reasoning, vol. I, pp. 447–533. Elsevier Science (2001)Bruni, R., Meseguer, J.: Semantic foundations for generalized rewrite theories. Theor. Comput. Sci. 360(1–3), 386–414 (2006)Clarke, L.A., Rosenblum, D.S.: A historical perspective on runtime assertion checking in software development. ACM SIGSOFT Softw. Eng. Notes 31(3), 25–37 (2006)Clavel, M., Durán, F., Eker, S., Lincoln, P., Martí-Oliet, N., Meseguer, J., Talcott, C.: All About Maude - A High-Performance Logical Framework. LNCS. Springer, Heidelberg (2007)Clavel, M., Durán, F., Eker, S., Lincoln, P., Martí-Oliet, N., Meseguer, J., Talcott, C.: Maude Manual (Version 2.6). Technical report, SRI International Computer Science Laboratory (2011). http://maude.cs.uiuc.edu/maude2-manual/Durán, F., Meseguer, J.: A Maude coherence checker tool for conditional order-sorted rewrite theories. In: Ölveczky, P.C. (ed.) WRLA 2010. LNCS, vol. 6381, pp. 86–103. Springer, Heidelberg (2010)Durán, F., Roldán, M., Vallecillo, A.: Invariant-driven strategies for Maude. Electron. Notes Theor. Comput. Sci. 124(2), 17–28 (2005)Goguen, J.A., Meseguer, J.: Equality, types, modules, and (why not?) generics for logic programming. J. Logic Program. 1(2), 179–210 (1984)Goguen, J.A., Meseguer, J.: Unifying functional, object-oriented and relational programming with logical semantics. In: Agha, G., Wegner, P., Yonezawa, A. (eds.), Research Directions in Object-Oriented Programming, pp. 417–478. The MIT Press (1987)Klop, J.W.: Term rewriting systems. In: Abramsky, S., Gabbay, D., Maibaum, T. (eds.), Handbook of Logic in Computer Science, vol. I, pp. 1–112. Oxford University Press (1992)Korel, B., Laski, J.: Dynamic program slicing. Inf. Process. Lett. 29(3), 155–163 (1988)Lassez, J.L., Maher, M.J., Marriott, K.: Unification Revisited. In: Minker, J. (ed.) Foundations of Deductive Databases and Logic Programming, pp. 587–625. Morgan Kaufmann, Los Altos, California (1988)Leavens, G.T., Cheon, Y.: Design by Contract with JML (2005). http://www.eecs.ucf.edu/ leavens/JML/jmldbc.pdfMartí-Oliet, N., Palomino, M., Verdejo, A.: Rewriting logic bibliography by topic: 1990–2011. J. Logic Algebraic Program. 81(7–8), 782–815 (2012)Meseguer, J.: Conditional rewriting logic as a unified model of concurrency. Theoret. Comput. Sci. 96(1), 73–155 (1992)Meseguer, J.: Multiparadigm logic programming. In: Kirchner, H., Levi, G. (eds.) ALP 1992. LNCS, vol. 632, pp. 158–200. Springer, Heidelberg (1992)Rocha, C., Meseguer, J., Muñoz, C.: Rewriting modulo SMT and open system analysis. In: Escobar, S. (ed.) WRLA 2014. LNCS, vol. 8663, pp. 247–262. Springer, Heidelberg (2014)Roşu, G.: From Rewriting Logic, to Programming Language Semantics, to Program Verification. In: Martí-Oliet, N., Ölveczky, P.C., Talcott, C., (eds.) Logic, Rewriting, and Concurrency. LNCS, vol. 9200, pp. 598–616. Springer, Heidelberg (2015)Roldán, M., Durán, F., Vallecillo, A.: Invariant-driven specifications in Maude. Sci. Comput. Program. 74(10), 812–835 (2009)TeReSe. Term Rewriting Systems. Cambridge University Press (2003

Debugging of Web Applications with Web-TLR

Web-TLR is a Web verification engine that is based on the well-established Rewriting Logic--Maude/LTLR tandem for Web system specification and model-checking. In Web-TLR, Web applications are expressed as rewrite theories that can be formally verified by using the Maude built-in LTLR model-checker. Whenever a property is refuted, a counterexample trace is delivered that reveals an undesired, erroneous navigation sequence. Unfortunately, the analysis (or even the simple inspection) of such counterexamples may be unfeasible because of the size and complexity of the traces under examination. In this paper, we endow Web-TLR with a new Web debugging facility that supports the efficient manipulation of counterexample traces. This facility is based on a backward trace-slicing technique for rewriting logic theories that allows the pieces of information that we are interested to be traced back through inverse rewrite sequences. The slicing process drastically simplifies the computation trace by dropping useless data that do not influence the final result. By using this facility, the Web engineer can focus on the relevant fragments of the failing application, which greatly reduces the manual debugging effort and also decreases the number of iterative verifications.Comment: In Proceedings WWV 2011, arXiv:1108.208

Rewriting-based repairing strategies for XML repositories

[EN] Keeping XML data in a consistent state w.r.t. both structure and content is a burdensome task. To maintain the consistency of ever-larger, complex XML repositories, suitable mechanisms that are able to x every possible inconsistency are needed. In this article, we present a methodology for semi-automatically repairing faulty XML repositories that can be integrated on top of an existing rewriting-based veri cation engine. As a formal basis for representing consistency criteria, we use a rule-based description formalism that is realized in the language Maude. Then, starting from a categorization of the kinds of errors that can be found during the veri cation process, we formulate a stepwise transformation procedure that achieves correctness and completeness of the XML repository w.r.t. its Maude formal speci cation while strictly observing the structure of the XML documents. With the aim of increasing the level of automation of our repair methodology, we also de ne two correction strategies and two completion strategies that reduce either the amount of information to be changed or the number of repair actions to be executed in order to deliver an XML repository that is both correct and complete. Finally, we describe a prototype implementation of the repairing tool, which we use for an experimental evaluation of our method with good results. ©2013 Elsevier Inc.All rights reserved.This work has been partially supported by the EU (FEDER) and the Spanish MEC project ref. TIN2010-21062-C02-02, and by Generalitat Valenciana ref. PROMETEO2011/052. This work was carried out during the tenure of D. Ballis’ ERCIM “Alain Bensoussan” Postdoctoral Fellowship. The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007–2013) under grant agreement n. 246016. F. Frechina was supported by FPU-ME grant AP2010-5681 and D. Romero by FPI-MEC grant BES-2008-004860 We would like to thank the anonymous reviewers for their helpful comments.Alpuente Frasnedo, M.; Ballis, D.; Falaschi, M.; Frechina, F.; Romero, D. (2013). Rewriting-based repairing strategies for XML repositories. The Journal of Logic and Algebraic Programming. 82(8):326-352. https://doi.org/10.1016/j.jlap.2013.05.002S32635282

Using conditional trace slicing for improving Maude programs

[EN] Understanding the behavior of software is important for the existing software to be improved. In this paper, we present a trace slicing technique that is suitable for analyzing complex, textually-large computations in rewriting logic, which is a general framework efficiently implemented in the Maude language that seamlessly unifies a wide variety of logics and models of concurrency. Given a Maude execution trace T and a slicing criterion for the trace (i.e., a piece of information that we want to observe in the final computation state), we traverse T from back to front and the backward dependence of the observed information is incrementally computed at each execution step. At the end of the traversal, a simplified trace slice is obtained by filtering out all the irrelevant data that do not impact on the data of interest. By narrowing the size of the trace, the slicing technique favors better inspection and debugging activities since most tedious and irrelevant inspections that are routinely performed during diagnosis and bug localization can be eliminated automatically. Moreover, cutting down the execution trace can expose opportunities for further improvement, which we illustrate by means of several examples that we execute by using iJulienne, a trace slicer that implements our conditional slicing technique and is endowed with a trace querying mechanism that increases flexibility and reduction power.This work has been partially supported by the EU (FEDER) and the Spanish MEC project ref. TIN2010-21062-C02-02, and by Generalitat Valenciana ref. PROMETEO2011/052. This work was carried out during the tenure of D. Ballis' ERCIM "Alain Bensoussan" Postdoctoral Fellowship. The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement No. 246016. F. Frechina was supported by FPU-ME grant AP2010-5681 and D. Romero by FPI-MEC grant BES-2008-004860.Alpuente Frasnedo, M.; Ballis, D.; Frechina, F.; Romero, DO. (2014). Using conditional trace slicing for improving Maude programs. Science of Computer Programming. 80:385-415. https://doi.org/10.1016/j.scico.2013.09.018S3854158

La innovación tecnológica en el marketing : publicidad dinámica

Frechina Navarro, F. (2008). La innovación tecnológica en el marketing : publicidad dinámica. http://hdl.handle.net/10251/8870.Archivo delegad

Red social geolocalizada sobre la tecnología de Google Maps : la innovación de la web asíncrona

Frechina Navarro, F. (2010). Red social geolocalizada sobre la tecnología de Google Maps : la innovación de la web asíncrona. http://hdl.handle.net/10251/8662Archivo delegad