A Web Specific Language for Content Management Systems

1
A Web Specific Language for Content Management
Systems

• Viðar Svansson, Roberto E. Lopez-Herrejon
• Computing Laboratory
• University of Oxford

2
Motivation

• Web application development is increasingly
  complex
• Several ways to cope with this complexity
• Web frameworks
• Basic infrastructure for web development
• Examples RubyOnRails, Zope
• Problems hard to master, e.g. API and coding
  conventions, multiple implementation technologies
• Content Management System (CMS)
• Sophisticated systems for authoring and
  controlling web applications sometimes built on
  top of a web framework
• General purpose but customizable for the
  organization profile
• Problems many custom requirements, still hard to
  master

3
Big Picture

• Our goal
• Facilitate the building of custom CMS by
  non-experts
• Our approach
• Develop a Domain Specific Language (DSL)
• Hide programming complexity
• Utilize Model-Driven Development technologies
• openArchitectureWare
• Generate a software product line infrastructure
• reuseable components and configuration profiles

4
Designing DSL Insights

• Websites are hierarchical
• Directories, index.html
• Webpages are hierarchical
• HTML, XML
• Content workflow can be modeled with state charts
• CMS systems can be built in terms of their
  required functionality

5
Web Specific Language (WSL) Fragment

• Application 'application' nameID ''
• (entitiesEntity)
• ''
• Abstract Entity Metadata Domain Feature
• Domain 'domain' nameID '' (entitiesEntity)
  ''
• Abstract Feature Content Workflow Permission
  
• Abstract Metadata
• Description Title Author
• Version URL Email Licence
• Abstract Content
• Base Folder Document File
• Event Image Link
• Base 'content' nameID ''
• (conceptsConcept)
• ''

• Abstract Stereotype Required Searchable
  Ordered
• Abstract Containment Contains Container
• Contains 'contains' (containmentID) ''
• Container 'container' (containmentID) ''
• Abstract Concept
• Metadata Field Containment
• Field
• (stereotypesStereotype)
• typeType nameID ''
• (attributesFieldAttribute)
• ''
• Abstract FieldAttribute
• Widget Title Description Default
  Stereotype

6
Akademia Case Study

• application Akademia
• domain Research
• title "Research Content"
• description "Concepts "
• folder ResearchProject
• title "Research Project"
• contains Publication
• reference groups
• title "Associated Groups"
• type ResearchGroup
• reference projects
• title "Related projects"
• type ResearchProject, Link
• required text aims

• Simple academic web sites
• An Akademia web site has
• Research projects
• Research groups
• Publications
• Other details

7
WSL Architecture
WSL
xText
WSLecore
WSLeditor
wsl2emf
Akademiawsl
Akademiaemf
emf2interfaces
emf2archetypes
emf2config
emf2profile
8
Product Line Infrastructure

• Profiles finer degree or variability
• System properties, i.e. string values in XML
  files
• Examples content-types, comments, versioning
• Tool GenericSetup to select and deploy components
• Define permissions and workflows
• CMS instance composed of multiple profiles

9
Output Examples
10
Lessons Learned

• Web apps (CMSs) are complex beasts
• Require detailed knowledge of the target to
  automate generation effectively
• Limitations found
• Missing association references in xText
  translation
• Template support for whitespace handling,
  important when targeting Python code
• Textual DSL was adequate
• Easier to learn, traditional versioning and
  editing support

11
Related Work

• Inspired by ArchGenXML (AGX)
• Transforms UML diagrams annotated with
  stereotypes of a Plone UML profile
• WebDSL Visser 07
• Proposes DSL for web applications with concepts
  similar to those available in a CMS
• Academic web site case study
• Models presentation in DSL
• Feature Oriented Model Driven Development (FOMDD)
  Trujillo et. al 07
• Combines Feature Oriented Programming (FOP) and
  MDD
• Algebraic representation of composition and
  synthesis

12
Future Work

• Application to a larger case study
• Assessment with actual web developers
• Extend DSL to accommodate other CMS functionality
• Portlets, composite content-types
• Algebraic properties of fields for computed
  fields
• Model algebraically as in FOMDD
• How the model obtained compares with other case
  studies?
• Integrate with a feature modeling tool