Instance Model Ad Hoc Meeting Minutes

Time

May 4, 2017, 17:00–18:00 CET

Attendees

Franck Chauvel (SINTEF), Derek Palma (Vnomic), Chris Lauwers, Priya TG (Netcracker).

Minute takers

Franck Chauvel (SINTEF)

Summary

1. Franck and Derek reviewed the new class diagrams that Franck had made. While he initially used EMF, he switched to Modelio (see http://modelio.org), which allows him to draw multiple diagrams of a single model.

2. What data types are needed? Franck propose to include TOSCA specific types such as Range or Version, as well as collections such as List and Map. Derek suggested to reuse the datatypes from ECore, to reuse as much as possible of what already exist. Additional types can be later added, either at the M3 or M2 level as needed.

3. Shall the model instance model be reflexive? Franck asked whether the model being reflexive, because, ideally, instance models should be self-contained. A reflexive model entails the definition of the notion of Class and Object. Derek suggested that we could directly reuse M3 level concepts (say ECore concepts for instance) to get this feature for free.

4. Do we need to model TOSCA types? Chris proposed to include TOSCA types in the instance model so that instance could directly refer to a "type" object. This implies to duplicate the class structure that describes instances and to link each instance-level concept to the corresponding type-level concept. Having such types could help check consistency for instance. Derek argued that this may lead to an oversized instance model and that promoting concepts from the M3 level could be sufficient. No decision was taken at this point.

5. Chris observed that the mix of meta-levels on the same illustration is very confusing. Derek suggested to use colours to visually identify which class comes from which metalevel. This shall be fixed in the next version.

Actions

· Franck to revise the UML class diagrams to better distinguish between the M3 and M2 concepts.

· Franck to invite to the next call on May 18, 2017, from 17:00 – 18:00 CET.

Instance Model Ad Hoc Meeting Minutes