INTPYTHON-487 Polymorphic Collection Support #269
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| def __iter__(self, *args, **kwargs): | ||
| for obj in super().__iter__(*args, **kwargs): | ||
| model_class = apps.get_model(obj._meta.app_label, obj._t) | ||
| yield model_class.objects.get(pk=obj.pk) |
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🤔 what is the flow here? is it doing N+1 queries to get the data?
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Jib mentioned that it's a temporary hack.
| if issubclass(_base, MultiModel): | ||
| MultiModel._subclasses.setdefault(_base, []).append(cls) | ||
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| # Get all the subclasses for my model |
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my model? our model. (don't know if it is good to post a meme here)
| node = stack.pop() | ||
| stack.extend(cls._subclasses.get(node, [])) | ||
| acc.add(node) | ||
| return [obj.__name__ for obj in acc] |
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Maybe adding obj.__module__ and then __name__ could potentially fix a collision. two modules could have the same name in two different files.
Lets say:
file1.py:
from base import A
class B(A):
passfile2.py
from base import A
class B(A):
passbase.py
class A:
passmain.py
from file1 import B
from file2 import B as B2
print(B.__name__, B2.__name__) # it prints-> B, B
print(B.__module__, B2.__module__). # it prints -> file2 file3
| # Save the classname as the _t before saving | ||
| def save(self, *args, **kwargs): | ||
| if not self._t: | ||
| self._t = self.__class__.__name__ |
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If the above comment is ok, we should also modify this one.
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It's an interesting implementation, but without support for formsets and admin, this seems of limited value. You'd have to edit all the child models separately since the add/edit forms for the parent model don't include child fields. Also, the fact that migrations only manage the parent model creates problems with adding/removing/renaming/changing fields on the child models (and of course, indexes, as you already mentioned). I think it would be better to target this idea for post-GA (e.g. Django 6.0) when we can have an implementation that relies on patches to Django that would make this work more smoothly. |
First draft multiple models in a collection: