Model And Transformation Management

*Generative Model Transformer*
First off lets make it easy on ourselves and NOT worry (yet) about distributed tool use (we can have this as an eventual goal, along with a "visual aspect). Web based or not I venture to say that whatever mechanisim we choose, once we introduce "distributed" use then the same problems will have to be addressed. --Jeff

Sure the distributed can come later, although once we have a web-based interface, the "only" ;-) other thing we need is a good central repository that can store models, see below. We could either use an SQL database or use an object database. What such a repository should allow you to do, is to open up a model for editing to a (small) group of people. --Jorn

:) I like your smile near "only". As soon as we have model repository there is no big difference how you access it. I think discussion on Web-based or not is not very much related to ModelAndTransformationManagement topic. What do you think? -- MarkKofman

Ultimately what I think you need is:

  • a BA may sit together with a customer, capturing model information, while a designer is watching the model evolve in a different location, who may then modify bits and pieces.
  • Similarly two designers/developers may collaboratively work on a shared model even though they're in different locations.
  • Locking: As long as the models are accessible from multiple locations and updated in a repository as changes occur, it may be sufficient for one person to have a lock and others being able to watch the changes (live!). This works if the editing lock on a package (model part) can be passed around in a small virtual team like a token. (Like using a walkie tackie, you aquire the lock by pressing a button that signals your request to the current owner of the lock). The most important thing though is very simple: a locking mechanism at a "package" level, that gives access to a manageable model part to one person. Basically it amounts to shared workspaces for collaboration. If models get large, several separate workspaces can be used by different groups of people, with each workspace dealing with a separate package (model part). But to start, we can keep it very simple: One person locks a package and works on it and then check it back in. The "repository" can consist of XMI files and versioning is CVS (or "Subversion". Have you seen that yet? It's apparently "next generation" CVS). --Jorn
  • Model comparisson and merge possibility -- MarkKofman
  • Decomposition of the model -- MarkKofman

Web based or not its about generation of a specification tool for use with a specific meta-model. Having said that, a web based interface seems to work well with the idea of "Dynamic" (re)generation of a specification medium.

  1. It works on almost all platforms and is (nearly) identical in appearence.
  2. We have access to a good cross platform servlet reference implementation that is open-source (used by eGen, so we know it works).
  3. We know it can work, even if we can't vouch for the distributed part. However, as I said earlier this is an issue that would have to be address regardless of the specification medium choosen.

Yes, exactly. --Jorn

Perhaps the alternatives would come with additional issues, who knows? --Jeff

  1. OK, its good, but it doesn't help anyhow in solving needs described above.
  2. I am not sure what do you mean here. Do you want to say that Tomcat is good enough?

I would also like to mention some negative points of Web-based tools. Those points in my opinion are quite important considering the fact that we are talking about development tools

  • They are slow comparing to fat clients
  • They are usualy inconvinient to use.
  • They are harder to develop well
  • There is a lot to reuse in Eclipse platform

To conclude I would say that still I don't see any big additional value comparing to Eclipse based solutions. If we are going to postpone model management problems, then we should also postpone solution ideas for now.

-- MarkKofman

Yes. That's why I suggest: let's see how far we get with EMF for version 0.1. Should hopefully allow us to bootstrap, and then focus on a single user, web-based interface for generated specification tools. --Jorn

-- JornBettin - 13 Jun 2004