Weaving aspects into web service orchestrations

Web Service orchestration engines need to be more open to enable the addition of new behaviours into service-based applications. In this paper, we illus- trate how, in a BPEL engine with aspect-weaving ca- pabilities, a process-driven application based on the Google Web Service can be dynamically adapted with new behaviours and hot-fixed to meet unforeseen post- deployment requirements. Business processes (the ap- plication skeletons) can be enriched with additional fea- tures such as debugging, execution monitoring, or an application-specific GUI. Dynamic aspects are also used on the processes themselves to tackle the problem of hot-fixes to long running processes. In this manner, composing a Web Service ’on-the-fly’ means weaving its choreography in- terface into the business process

Service Oriented Architecture Definition Using Composition of Business-Driven Fragments

International audienceServices Oriented Architecture are built through the compo- sition of services (e.g. Web Services) to define complex business process (e.g. Orchestrations). Well known methodologies focus on identifying ser- vices and orchestrations at design time. However the orchestration design phase is still a heavy burden, as it induces to deal with both technical and business domain concerns. This article proposes to use an evolution framework (Adore) to capitalize architects knowledge and best practices into “evolutions”. Architects can build business-driven orchestrations by composing reusable “evolutions” following a design–by–composition ap- proach. We apply this approach to build a legacy Soa called Seduite (validation platform for the French national research project Faros)

Contract Aware Components, 10 years after

The notion of contract aware components has been published roughly ten years ago and is now becoming mainstream in several fields where the usage of software components is seen as critical. The goal of this paper is to survey domains such as Embedded Systems or Service Oriented Architecture where the notion of contract aware components has been influential. For each of these domains we briefly describe what has been done with this idea and we discuss the remaining challenges.Comment: In Proceedings WCSI 2010, arXiv:1010.233

Aspects of Assembly and Cascaded Aspects of Assembly: Logical and Temporal Properties

Highly dynamic computing environments, like ubiquitous and pervasive computing environments, require frequent adaptation of applications. This has to be done in a timely fashion, and the adaptation process must be as fast as possible and mastered. Moreover the adaptation process has to ensure a consistent result when finished whereas adaptations to be implemented cannot be anticipated at design time. In this paper we present our mechanism for self-adaptation based on the aspect oriented programming paradigm called Aspect of Assembly (AAs). Using AAs: (1) the adaptations process is fast and its duration is mastered; (2) adaptations' entities are independent of each other thanks to the weaver logical merging mechanism; and (3) the high variability of the software infrastructure can be managed using a mono or multi-cycle weaving approach.Comment: 14 pages, published in International Journal of Computer Science, Volume 8, issue 4, Jul 2011, ISSN 1694-081

Introducing Security Access Control Policies into Legacy Business Processes

International audienceApplying separation of concerns approaches into business process context generally results in several initiatives oriented to automatic generation of aspect code, generation of specific code according to the kind of concern (code for mapping roles and permissions derived from RBAC model for example), or proposition of new mechanisms as dedicated aspectual languages. Most of these initiatives only consider functional behaviours of business process, omitting special behaviours derived from quality attributes such as security, which can be modelled as concerns that must be supported in the business process. In this paper we propose the integration of cross-cuttings standardized control access policies (based on RBAC model and Oasis XACML) into legacy business processes, using a separation of concerns approach

A Pattern-Based Approach to Manage Model References

Model references play an important role in model integration, especially when models belonging to different domains are to be integrated. They are also needed in various model transformation tasks. In some cases, they need to be instantiated systematically, following certain rules. This calls for an instantiation specification of model references. In this paper we propose a pattern-based approach for modeling, specifying, and finally applying model references. We represent model references as so-called collaboration patterns, modeled as UML collaborations. We further describe the instantiation rules of collaboration patterns. A tool has been implemented for establishing the model references according to the specification, allowing the designer to assist in the process of semi-automated model reference instantiation. We demonstrate the usefulness of the approach and tools by applying them in designing Web service orchestrations

Modeling Service Choreographies with Rule-enhanced Business Processes

The participation at EDOC 2010 was overwhelming in every positive sense, and I am very thankful to the committee for this award. Our presentation was received highly positive and triggered several questions. The questions were mainly about the relations of our work with the use of ontology and vocabulary representation languages, and our plans for developing executable models rather than generating code from models. In fact, this was already in line with our previous plans and research directions. Some of these discussions even continued during the following days. In particular, we had plans for two concrete collaborations. One is related to the development of a formal semantics of the rBPMN languages by using process algebra, that is, by using the mCRL2 language in particular. Moreover, we also created a common plan for integration of semi-structured English language for defining business rules and vocabularies. This will also allow us to have a more effective way to capture rules in rBPMN process models. Moreover, our presentation of the rBPMN editor, as an practical implementation tool for the work with the rBPMN language received a special attention, and several researchers have already approached us to establish research collaboration and/or to use our tool, which is now publically available. The overall experience was also extremely valuable. The program of the conference covered nearly all of the diverse topics in enterprise computing. That is, the selected papers cover engineering aspects in many phases of development life cycle of enterprise systems, especially those designed for distributed environments. I have also delivered a keynote at the VORTE 2010 workshop with the audience with was the largest of all workshop keynotes at the conference. The participants very positively received my insights. In a very interactive session, we discussed some of the main research challenges important for better integration of business rules and business process modeling languages.The research community has so far mainly focused on the problem of modeling of service orchestrations in the domain of service composition, while modeling of service choreographies has attracted less attention. The following challenges in choreography modeling are tackled in this paper: i) choreography models are not well-connected with the underlying business vocabulary models. ii) there is limited support for decoupling parts of business logic from complete choreography models. This reduces dynamic changes of choreographies; iii) choreography models contain redundant elements of shared business logic, which might lead to an inconsistent implementation and incompatible behavior. Our proposal – rBPMN – is an extension of a business process modeling language with rule and choreography modeling support. rBPMN is defined by weaving the metamodels of the Business Process Modeling Notation and REWERSE Rule Markup Language. To evaluate our proposal, we use service-interaction patterns and compare our approach with related solutions

A coordination protocol for user-customisable cloud policy monitoring

Cloud computing will see a increasing demand for end-user customisation and personalisation of multi-tenant cloud service offerings. Combined with an identified need to address QoS and governance aspects in cloud computing, a need to provide user-customised QoS and governance policy management and monitoring as part of an SLA management infrastructure for clouds arises. We propose a user-customisable policy definition solution that can be enforced in multi-tenant cloud offerings through an automated instrumentation and monitoring technique. We in particular allow service processes that are run by cloud and SaaS providers to be made policy-aware in a transparent way

Geospatial data integration with Semantic Web services: the eMerges approach

Geographic space still lacks the semantics allowing a unified view of spatial data. Indeed, as a unique but all encompassing domain, it presents specificities that geospatial applications are still unable to handle. Moreover, to be useful, new spatial applications need to match human cognitive abilities of spatial representation and reasoning. In this context, eMerges, an approach to geospatial data integration based on Semantic Web Services (SWS), allows the unified representation and manipulation of heterogeneous spatial data sources. eMerges provides this integration by mediating legacy spatial data sources to high-level spatial ontologies through SWS and by presenting for each object context dependent affordances. This generic approach is applied here in the context of an emergency management use case developed in collaboration with emergency planners of public agencies

Aspectual Session Types

International audienceMultiparty session types allow the definition of distributed processes with strong communication safety properties. A global type is a choreographic specification of the interactions between peers, which is then projected locally in each peer. Well-typed processes behave accordingly to the global protocol specification. Multiparty session types are however monolithic entities that are not amenable to modular extensions. Also, session types impose conservative requirements to prevent any race condition, which prohibit the uni- form application of extensions at different points in a protocol. In this paper, we describe a means to support modular extensions with aspectual session types, a static pointcut/advice mechanism at the session type level. To support the modular definition of crosscut- ting concerns, we augment the expressivity of session types to al- low harmless race conditions. We formally prove that well-formed aspectual session types entail communication safety. As a result, aspectual session types make multiparty session types more flexible, modular, and extensible