Towards Model-driven Web Services development

1. Towards Model-driven Web Services development MihirDaptardar Software Engineering 577b Center for Systems and Software Engineering (CSSE) Viterbi School of Engineering

2. Motivation • Developed applications incorporating web services before (class projects and commercial prototype) • More emphasis on getting work done rather than methodology • Desire to learn a more systematic rather generic way to go about implementation • Software Engineering class is a great platform

3. Have I seen this before in the course? • Covered in different lectures • General Idea covered in Model Based Software Engineering (MBSE) • Web Services covered in as a part of the RESTfulArchitectures • Also highlighted by one of the guest speakers, Mark Goldin, CTO, Cornerstone onDemand

4. What is a Web Service? • A web service is a collection of open protocols and standards used for exchanging data between applications or systems. • Software applications written in various programming languages and running on various platforms can use web services to exchange data over computer networks like the Internet in a manner similar to inter-process communication on a single computer. Ref: http://www.tutorialspoint.com/webservices/what_are_web_services.htm

5. What is model-driven engineering? • Model-driven engineering (MDE) is a software development methodology which focuses on creating and exploiting domain models (that is, abstract representations of the knowledge and activities that govern a particular application domain), rather than on the computing (or algorithmic) concepts. Ref: http://en.wikipedia.org/wiki/Model-driven_engineering

6. Model-driven Web services • High advancement in the field of mobile computing • Web services need to be consumed by platform specific clients • There is no general static requirements • MDE is on the rise in the research world with lots of advancement in platforms and tools

7. Model-driven Engineering • Types: • Platform Independent Model (PIM) • Abstract representation • No Implementation details • Platform Specific Model (PSM) • Specific representation • Detailed implementation documentation

8. Focus • “The importance of the proposed framework lies in the high degree of automation achieved, which improves the efficiency of the development process, since is allows developers to generate code for various platforms with limited effort” • Summarizing: • Focus on maximum automation rather than the semantics of transformer • Application of the proposed solution across diverse platforms

9. Pros Cons • More time modeling and less time coding (if you enjoy coding). • Usability of generated code. • Independence of a specific programming language • Achieve high complexity • Encourages good OO • Can communicate effectively with stakeholders by providing a model. • Create a roadmap for developers to follow. • Track the history of every decision. Ref: http://greenbay.usc.edu/csci577/spring2013/uploads/readings/ec/EC04-MBSE.ppt

10. Related work • Dunkel and Brunspropose a model-driven approach that allows the client's GUIs and the service workflow using graphical models, which are then transformed into XML-based descriptions (i.e., XForms code). • Kapitsakipresent an approach which proposes complete separation of the Web application functionality from the context adaptation. The approach tackles and automates the development of context-aware Web applications, intended mainly for mobile users, which are formulated by third-party WSs.

11. Proposed Framework

12. Proposed Framework • Presentation Modeling Language (PML) and Web Service Design Language (WSDL) models designed at model time and are input for code generators • Focus is mainly on PML. Modeling GUI’s in form of screen layout • GUI’s comprise of standard elements like textbox, labels, buttons etc

13. Overview: PML

14. Mapping: Brief Idea

15. Transformation • Focus is mainly on Presentation layer. • Targeted platforms: • Java • Android • Windows Mobile • Windows Desktop

16. Code Generation Process • openArchitectureWare (oAW) enables the development of code generators by defining model to text transformation rules • Components: • Xpand – Template language • Workflow Execution Engine • Check – Supplementary Language

17. Example: Android

18. Example: Windows Mobile

19. Use Case: Book Store • Outline: • Bookstore WS provides means for searching and purchasing books • Input = Name of the book (Title) • Output = All details of the book

20. Top Level Elements

21. Container: Example

22. GUI Code Generated

23. View on phone

24. Statistics

25. Summarizing • MDE automates development of Web Service oriented applications is presented in the study and also advised for multiple interfaces • Code Generators proposed have been implemented using openArchitectureWare and demonstrated using a Bookstore Use case

26. REUSE, REDUCE, RECYCLE • This not just applies to environment but also applies to programming 

27. GOOD LUCK EVERYONE! • Questions?

28. References • A Model-Driven Framework for Developing Web Service Oriented Applications - AchilleasAchilleos, Georgia M. Kapitsaki and George A. Papadopoulos • Model-driven Web Services Development -Roy Grønmo, David Skogan, Ida Solheim, Jon Oldevik