Model-Driven Web Engineering Research Articles

A Survey of Requirements Specification in Model-Driven Development of Web Applications

Model-driven development has become more and more important in the last few years. In the context of web application development, many web Engineering methods that propose model-driven development processes have appeared. However, earlier stages of these processes are seldom considered and few of these methods rigorously face the problems of specifying web application requirements and translating them into the proper conceptual model. However, it is widely recognized that requirements engineering activities are essential to obtain quality software products. This article surveys Model-driven web engineering methods in a comparative study and analyzes the techniques proposed for specifying functional, data and navigational requirements as well as the mechanisms provided for automatically translating these requirements into conceptual models. Our main goal is to provide a critical view of the support that is provided by these methods for handling web application requirements in order to show their current limitations and strengths.

Guest Editorial to the Theme Section on Model-Driven Web Engineering

Model-Driven Engineering (MDE) is becoming a widely accepted paradigm for the design and development of complex distributed applications.MDEadvocates the use ofmodels and model transformations as key artefacts in all phases of the software process, from system specification and analysis, to design, development and testing. Each model usually addresses one concern, independently from the rest of the issues involved in the construction of the system. Thus, the basic functionality of the system can be separated from its final implementation, and the business logic can be separated from the underlying platform technology, etc. Transformations between models enable the automated implementation of a system from the different models defined for it. The Web Engineering (WE) community soon discovered that the key aspects of MDE (abstraction through modeling; separation of concerns by multi-viewpoint specification, and software development by model transformation) perfectly matched the principles and practices promoted by WE, and allowed Web application designers to address some of their

Using weaving models to automate model-driven web engineering proposals

Model-Driven Web Engineering is a new approach for Web Information Systems development whose basic assumption is the consideration of models as first-class entities. Basically, each step of the process consists of a model transformation that generates one or more target models from one or more source models. However, the special nature of the behavioural models implied at the early stages of a Model-Driven Web Engineering process complicates the specification of a model transformation that works for any input model. In such situations, it is not feasible to automate the whole development process since some design decisions have to be considered before executing each transformation. This work shows how we solve this problem in SOD-M, a model-driven approach for the development of Service-Oriented Web applications. The technique proposed is based on the use of weaving models as annotation models and it can be easily generalised to other domains and contexts.

Model-driven component adaptation in the context of Web Engineering

Currently, Web-based applications are no longer monolithic and isolated systems but, rather, distributed applications that need to interoperate with third-party systems, such as external Web services, LDAP repositories or legacy applications. When one component provides a service that the Web application requires, it is often not possible to bind the two systems together if they were not programmed to have compatible collaboration specifications. Modeling the adaptation between a Web application and external assets becomes therefore an essential issue in any realistic model-driven development scenario. However, most of the existing Web Engineering proposals do not take this issue into account, or they simply address it at the implementation level (in a platform-specific way). In this work, we discuss the problems involved in dealing with component adaptation within the context of Model-Driven Web Engineering and show how design patterns can help addressing it. We first identify the major interoperability problems that can happen when integrating third-party application or legacy systems into our Web systems, and then propose the mechanisms that need to be put in place at the design level to generate the appropriate specification of adapters that compensate for the possible mismatches and differences. We base our proposal on well-known design patterns as they are established solutions to recurring problems, and the generation of code from them is normally straightforward.

Bridging WebML to model-driven engineering: from document type definitions to meta object facility

Meta-models are a prerequisite for model-driven engineering (MDE) in general and consequently for model-driven web engineering in particular. Various web modelling languages, however, are not based on meta-models and standards, like object management group's prominent meta object facility (MOF). Instead they define proprietary languages rather focused on notational aspects. Thus, MDE techniques and tools cannot be deployed for such languages preventing to exploit the full potential of MDE in terms of standardised storage, exchange and transformation of models. The WebML web modelling language is one example that does not yet rely on an explicit meta-model in the sense of MDE. Instead, it is defined in terms of a document type definition (DTD), and implicitly within the accompanying tool. Code generation then has to rely on model-to-code transformations based of extensible stylesheet language transformations (XSLT). We propose a meta-model for WebML to bridge WebML to MDE. To establish such a meta-model, instead of remodelling WebML's meta-model from scratch, a semi-automatic approach is provided that allows generating MOF-based meta-models on the basis of DTDs. The meta-model for WebML accomplishes the following aims: first, it represents an initial step towards a transition to employ MDE techniques within the WebML design methodology. Second, the provision of a MOF-based meta-model ensures interoperability with other MDE tools. Third, it represents an important step towards a common meta-model for Web modelling in future.