Using MDA in Web Software Architectures

1
Using MDA in Web Software Architectures
Santiago Meliá Cristina Cachero Jaime
Gómez Universidad de Alicante Spain
2
Content

• Introduction
• Motivation
• Work Context Goals.
• WebSA Web Software Architecture.
• WebSA expressed with MDA. The view Model.
• Logical Architecture View in MDA.
• Generation strategy.
• Extension of the Architecture for MDA Models.
• Conclusions Future Work

3
1. Introduction

• The new challenges posed by Internet Market
  imply
• Development of more sophisticated Web
  Applications in a shorter period of time.
• Higher quality level to satisfy more demanding
  clients.
• The possibility to cover a vast diversity of web
  applications with different non functional
  requirements like number of clients, security,
  maintenance,etc.

4
1. Introduction

• Work context
• Up to now, Web methodologies (OO-H Cachero03,
  UWEKoch03, OOHDM, Schwabe99,etc) have paid
  little attention to non functional requirements
  for web applications.
• Web generation techniques are only used to obtain
  code for a predefined architecture of web
  applications.
• Objectives
• Integrate software architecture into Web
  Applications in order to cover the gap between
  web design and non functional requirements.
• Have the ability to generate code able to cover
  the vast diversity of web applications.

5
2. Web Software Architecture

• A new proposal called WebSA (Web Software
  Architecture) which is based on two main aspects
• The definition of specific software architecture
  models for Web (DSSA) to complement other UML
  proposals in the specification of Web
  Applications.
• The use of the MDA standard OMG 2001 to
  formalize and describe such models.

6
3. WebSA expressed with MDA

• OMG2001 MDA defines an architecture for models
  and provides a set of guidelines for structuring
  specifications expressed as models.
• It defines concepts as View, Refinement,
  Abstract.
• WebSA splits the web software architecture
  description in several concurrent views as other
  authors do with UML Krunchen95 Hofmeister et
  all. 1999.
• WebSA does this using also MDA and focusing on
  the web domain, which allows for a higher level
  of details in the specification process.

7
3.1 The WebSA view model

• This view model represents briefly the reference
  model of WebSA.

8
3.2 Logical architecture view in MDA

• The Logical Architecture defines the set of
  logical components (subsystems, modules and/or
  software components) and the relationships
  between them.
• The WebSA logical architecture is subdivided in
  three models
• Subsystem Model determines which are the
  subsystems that make up our application and the
  best distribution in layers of our system.
• Web Component Configuration Model provides an
  ontology of web abstract components and
  connectors that are particular to the web domain.
  
• Web Component Integration Model connects the
  functional and the architectural views under a
  common set of concrete components, modules and
  connectors.

9
3.2 Logical architecture view in MDA

• The three architectural models are Independent
  from the Platform.
• Integration Model is defined at a level of
  abstraction similar to that of the EDOC
  profileOMG 2002.
• WebSA is capable of automatically providing
  different mappings platforms such as EJB, CORBA
  or .NET.

10
3.2 Logical architecture view in MDA

• Possibility to classify the Web Integration Model
  as PIMs in the context of MDA.
• Integration Model is defined at a level of
  abstraction similar to that of the EDOC
  profileOMG 2002.

11
3.3. WebSA Generation Strategy
XML Interface
J2EE
.NET
CORBA...
Standard PSM
12
4. The Problem with Traditional MDA

• MDA, OMG 2001 when referring to quality
  attributes says it is desirable to support and
  integrate such features in the modeled
  applications. Such integration can only be
  achieved, as stated in Bass et al. 2000, by
  specifying the software architecture system.
• The subsystem model and the web component
  configuration model cannot be integrated in the
  traditional views of MDA because they are
  independent from the problem domain, and are
  exclusively influenced by the non functional
  requirements or quality attributes.

13
4. Extension of the architecture for MDA Models

• Extended architecture provides
• A more rigorous mapping between the analysis
  phase and the design phase.
• A better quality of the generated code, because
  it allows the definition of a generation
  mechanism where both the functional and the
  architectural parts are combined

14
Conclusions Future Works

• Conclusions
• We have presented a new proposal called WebSA for
  the development of web applications.
• Its aim is to extend the traditional MDA so as to
  capture the non functional requirements.
• We have proposed a code generation approach for
  mapping a WebSA specification to an
  implementation.
• Future Works
• We are in the process of defining the UML profile
  of WebSA.
• We are going to extend the VisualWADE CASE Tool
  to support this approach.
• We intend to generate an XML specification to
  feed template-code generators.

15
Thanks for your attention!!
Questions?