Expose JupyterCad 3d view and APIs in notebook

[trungleduc]

API example:

from jupytercad.notebook import CadDocument
a = CadDocument('examples/cut.FCStd')
box = a.get_object('Box')
box.parameters.Height = 1
box.update_object()

jcadapi.mp4

Done

• Add mime renderer for jcad and fcstd content
• Add APIs to interact with JupyterCad objects.

Todo

• Make the Caddocument constructor waits for the content coming from the frontend. -> No solution yet

[github-actions]

👈 Launch a Binder on branch trungleduc/jupytercad/notebook

[trungleduc]

@hbcarlos I'm still having issues with file saving with the latest commit.

[martinRenou]

I'm wondering if this should be called automatically whenever the underlying parameters changed.

Instead of:

box.parameters.Height = 1
box.update_object()

You would just do:

box.parameters.Height = 1

This would be closer to the ipywidgets vision, if that is a goal we'd like to follow.

In ipywidgets, you can also hold changes so that we do not crowd the comm channel with too many messages:

with widget.hold_sync():
    widget.value1 = 1
    widget.value2 = 2
    widget.value3 = 3

We could maybe think of having something equivalent here.

[trungleduc]

I would love to do so, but pydantic does not have the field observation (I think @davidbrochart is working on it).
I use this approach in JupyterCad but we definitely should have something as you describe in the standalone version of ypywidgets frontend.

[davidbrochart]

See https://github.com/davidbrochart/ypywidgets/issues/6.

[martinRenou]

Why is this code here? I don't really understand what it has to do with the rest of the _handle_comm_open method.

[trungleduc]

Basically, this snippet is done by WebSocketProvider, in the case of opening a new widget without providing the file path, we don't initialize the WebSocketProvider but jcadModels (and then the 3D viewer) still expects that its awareness has the user information.

[martinRenou]

This code may be too complex? It's more or less the same as:

Suggested change

	class SingletonMeta(type):
	_instances = {}
	def __call__(cls, *args, **kwargs):
	if cls not in cls._instances:
	instance = super().__call__(*args, **kwargs)
	cls._instances[cls] = instance
	return cls._instances[cls]
	class ObjectFactoryManager(metaclass=SingletonMeta):
	def __init__(self):
	self._factories: Dict[str, type[BaseModel]] = {}
	def register_factory(self, shape_type: str, cls: type[BaseModel]) -> None:
	if shape_type not in self._factories:
	self._factories[shape_type] = cls
	def create_object(
	self, data: Dict, parent: Optional[CadDocument] = None
	) -> Optional[PythonJcadObject]:
	object_type = data.get('shape', None)
	name: str = data.get('name', None)
	if object_type and object_type in self._factories:
	Model = self._factories[object_type]
	args = {}
	params = data['parameters']
	for field in Model.__fields__:
	args[field] = params.get(field, None)
	obj_params = Model(**args)
	return PythonJcadObject(
	parent=parent,
	name=name,
	shape=object_type,
	parameters=obj_params,
	)
	return None
	OBJECT_FACTORY = ObjectFactoryManager()
	OBJECT_FACTORY.register_factory(Parts.Part__Box.value, IBox)
	OBJECT_FACTORY.register_factory(Parts.Part__Cone.value, ICone)
	OBJECT_FACTORY.register_factory(Parts.Part__Cut.value, ICut)
	OBJECT_FACTORY.register_factory(Parts.Part__Cylinder.value, ICylinder)
	OBJECT_FACTORY.register_factory(Parts.Part__Extrusion.value, IExtrusion)
	OBJECT_FACTORY.register_factory(Parts.Part__MultiCommon.value, IIntersection)
	OBJECT_FACTORY.register_factory(Parts.Part__MultiFuse.value, IFuse)
	OBJECT_FACTORY.register_factory(Parts.Part__Sphere.value, ISphere)
	OBJECT_FACTORY.register_factory(Parts.Part__Torus.value, ITorus)
	CLASSES = {
	Parts.Part__Box.value: IBox,
	Parts.Part__Cone.value: ICone,
	Parts.Part__Cut.value: ICut,
	Parts.Part__Cylinder.value: ICylinder,
	Parts.Part__Extrusion.value: IExtrusion,
	Parts.Part__MultiCommon.value: IIntersection,
	Parts.Part__MultiFuse.value: IFuse,
	Parts.Part__Sphere.value: ISphere,
	Parts.Part__Torus.value: ITorus,
	}
	def create_object(
	data: Dict, parent: Optional[CadDocument] = None
	) -> Optional[PythonJcadObject]:
	object_type = data.get('shape', None)
	name: str = data.get('name', None)
	if object_type and object_type in CLASSES:
	Model = CLASSES[object_type]
	args = {}
	params = data['parameters']
	for field in Model.__fields__:
	args[field] = params.get(field, None)
	obj_params = Model(**args)
	return PythonJcadObject(
	parent=parent,
	name=name,
	shape=object_type,
	parameters=obj_params,
	)
	return None

[trungleduc]

I want to use a factory pattern to register the shapes at the same place as their definition, the register_factory method should be called in the appropriate shape classes. But then shape classes are generated automatically and I didn't find a way to add this register_factory call to the generated files, so we ended up with this implementation.

Another advantage of the registering method is that we can prevent removing or overwriting existing factories.

[martinRenou]

Thanks!