MeidyaCom-Policy

MeidyaCoM-Policy is an extension of MeidyaCoM project. MeidyaCoM project supports the modeling of correct by design Publish/Subscribe architectural style and the basic reconfiguration operations for the adaptation of software architecture. MeidyaCoM-Policy is an approach which proposes a way of applying these operations with respect to architectural style by the means of repair policies.

The MeidyaCoM-Policy approach is based principally on three steps:

• In the first step, we propose a UML-based approach for modeling repair policies. We introduce a new UML profile, using extended UML 2.0 notations. The profile guides and assists design activities for describing repair policies using a visual notation. A software environment supporting the different features of this approach has been implemented and integrated as a plug-in in the open source Eclipse framework.
• In the second step, we implement a rule-based generator which automatically translates the repair policy model specified using our UML profile into Z specifications. From MeidyaCoM project, we obtain the architectural style described with Z specifications. In our work, we improved this architectural style with QoS properties.
• In the third step, we use the theorem proving Z/Eves to prove the soundness (i.e. every execution of the policy will place the system in a correct state w.r.t. the original style) and the consistency (i.e. absence of any contradiction between architectural invariants) of the generated repair policies.

Tools Support

MeidyaCoM-Policy is enhanced by an Eclipse plug-in. It is a graphical modeling tool that ensures an easy and efficient modeling way for users. This plug-in allows us to create a graphical editor which implements our UML profile.

The repair policy diagram editor is a tool where diagrams as well as graphical elements can be created to model policies. Graphical elements can be picked up from a Tool palette and created in the Diagram editor pane in a “drag-and-drop” way.

The graphical editor generates an XML file (Download the PolicyFollowMe.xml). The plug-in transforms this XML file, according to transformation rules expressed with the XSLT language (eXtensible Styles Language Transformation), (Download the PolicyTransformation.xsl) into Z specifications saved in a LATEX (.tex) file. This LATEX file will then be imported under the Z/Eves theorem prover to visualize Z schemas, to validate their syntax and to verify the theorems (Download the ProofSteps.pdf).

Demonstration

Case Studies

We applied MeidyaCom-Policy on two case studies. As an example, we present:

• Modelling phase: The Screenshot of the models
• Validation phase: The generated XML file
• Verification phase: The generated Z file

• Emergency Operation System (EOS) [link]

• Follow Me (FM) [link]

Download

MeidyaCom-Policy Plug-in Description : A plug-in based on a UML profile. The repair policy diagram editor is a tool where diagrams as well as graphical elements can be created to model policies. Graphical elements can be picked up from a tool palette and created in the diagram editor pane in a “drag-and-drop” way.

Setup : The MeidyaCom-Policy plug-in should be added under the plugins directory of the Eclipse framework.

• Download the MeidyaCom-Policy Plug-in

• Download the PolicyTransformation.xsl

Contributors

• Msc. Imen Tounsi [Email]
• Dr. Mohamed Hadj Kacem [Email]
• Dr. Imen Loulou [Email]
• Pr. Ahmed Hadj Kacem [Email]

Research Group

ReDCAD Research Unit (Tunisia)

National School of Engineers of Sfax
Route de la Soukra km 3.5 B.P., 1173, 3038 Sfax - Tunisia

Related papers

• S. Kallel, M. Hadj Kacem, and M. Jmaiel. Modeling and enforcing invariants of dynamic software architectures. Software and Systems Modeling, 11:127–149, 2012.

• I. Loulou, M. Jmaiel, K. Drira, and A. Hadj Kacem. P/S-CoM: Building correct by design publish/subscribe architectural styles with safe reconfiguration. Journal of Systems and Software, 83(3):412–428, March 2010.

• I. Loulou, I. Tounsi, M. Hadj-Kacem, A. Hadj-Kacem, and M. Jmaiel. A formal architecture-centric approach for safe self-repair. In In Second International Conference on Web and Information Technologies (ICWIT'09), Kerkennah Island, Sfax, Tunisia, June 2009

• I. Loulou, I. Tounsi, M. Hadj-Kacem, A. Hadj-Kacem, and M. Jmaiel. Making sound policies for self-healing systems. In 9ème Conférence Internationale sur les Nouvelles Technologies de lREpartition (NOTERE'09), pages 178-185, Montreal - Canada, July 2009.

• Imen Tounsi. Une approche pour la modélisation et la vérification des politiques d'adaptation pour le style P/S. Master's thesis, Faculté des Sciences Économiques et de Gestion de Sfax, 2010.