Batch registering multiple classes in blender 2.8


Actually Jacques having ‘auto_load.ignore’ - for ignoring some .py files, or folders would be cool. I will try to implement it.


Not sure if it’s an error in the auto_load script or in my addon:

All my custom nodes are inheriting only from my base node, not from bpy.types.Node:

class LuxCoreNodeMaterial(bpy.types.Node):

class LuxCoreNodeMatGlass(LuxCoreNodeMaterial):

Since the auto_load script only checks the direct base classes, it does not register these nodes.
Should auto_load recursively check all base classes of base classes, or should I change my addon like this:

class LuxCoreNodeMaterial:

class LuxCoreNodeMatGlass(LuxCoreNodeMaterial, bpy.types.Node):


I think I tried using the class LuxCoreNodeMatGlass(LuxCoreNodeMaterial): in the past and it did not work for me. So I also use the class LuxCoreNodeMatGlass(LuxCoreNodeMaterial, bpy.types.Node): approach in Animation Nodes.

However I just tested it again and found that it works now. So I’d say the bug is in auto_load.

Could you test if it works when you change line 98 from if any(base in base_types for base in cls.__bases__): to if any(issubclass(cls, base) for base in base_types):?

Ah, just remembered that then the problem is that it will try to register LuxCoreNodeMaterial as well, but it has no bl_idname, so it will fail… Maybe that was the reason I used the other approach…


This works.

No, this is fine, the old register_module did the same and it worked.
It’s a bit ugly to have base classes registered that are never actually instanced, but I can live with that.

I only noticed problems with the first approach once with node trees, so I wondered if it is discouraged in Blender?


What problems did you notice?

Just looked at Blenders code and seems like it uses the second approach, I have not found any example where it uses the first approach yet. (e.g. see here

Personally, I think the first approach should be discouraged. Being a bit more explicit about what is a node/operator/panel/… can’t hurt.

Also that probably makes the automatic class discovery faster. Not sure by how much though, maybe it is not noticeable.


Unfortunately I don’t remember the details, but I think it was about a BoolProperty in the base class. With the first approach the subclasses could not access the BoolProperty, or something like that.

Thanks, I will switch to the second approach. Thank you for investigating.