Add Initial Data Models for SysML v2

[danyeaw]

This is an initial implementation of what was discussed in #2584, to create our Python data models for SysML v2 by using the SysML Pilot Implementation EMF ecore meta models with pyecore.

I also filed Systems-Modeling/SysML-v2-Pilot-Implementation#496, since it appears that the SysML ecore doesn't actually depend on the KerML ecore, it redefines everything. To work around this, I did a lot of manual editing of the resulting pyecoregen models. We could work towards getting this fixed upstream and automating any other changes needed.

What does everyone think about this approach?

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PR Type

What kind of change does this PR introduce?

• Bug fix
• Feature
• Chore (refactoring, formatting, local variables, other cleanup)
• Documentation content changes

What is the current behavior?

Issue Number: #2584

What is the new behavior?

Does this PR introduce a breaking change?

• Yes
• No

Other information

[danyeaw]

I created pyecore/pyecore#135 to fix the Dependency Review failure.

[amolenaar]

For this to really work, the code should interact with our event system and emit the right events (attribute changes, association updates, etc.).

Does this imply we should also be able to load/save ecore files in Gaphor?

[danyeaw]

For this to really work, the code should interact with our event system and emit the right events (attribute changes, association updates, etc.).

The intention of this was an equivalent of our UML data model that we have today but for SysML. I think you are pointing out that since Gaphor assumes that the underlying model is UML, we may need to make significant updates to accomodate a new one. Is that what you mean?

Does this imply we should also be able to load/save ecore files in Gaphor?

Potentially, but I didn't have that use case in mind.

[amolenaar]

For this to really work, the code should interact with our event system and emit the right events (attribute changes, association updates, etc.).

The intention of this was an equivalent of our UML data model that we have today but for SysML. I think you are pointing out that since Gaphor assumes that the underlying model is UML, we may need to make significant updates to accomodate a new one. Is that what you mean?

I think it's fine that the model is not based on our UML model. It should be based on the Core model though, since Element contains the nitty gritty details on how changes are propagated from the model to the rest of the application.

[amolenaar]

@danyeaw Do you still want to try to make Gaphor work with ECore? Or can we close thos PR?