Abstract base PolymorphicModels cause field name clashes

[julianwachholz]

In a scenario where your base PolymorphicModel is abstract (for example, when you don't need a "simple" Project, a ForeignKey on it will cause field name clashes:

class BaseProject(PolymorphicModel):
    owner = models.ForeignKey(User, related_name='projects')
    class Meta:
        abstract = True

class ArtProject(BaseProject):
    # add some fields
    pass

class ResearchProject(BaseProject):
    # add some fields
    pass

This will cause the following errors (when running ./manage.py validate):

app.artproject: Accessor for field 'owner' clashes with related field 'User.projects'. Add a related_name argument to the definition for 'owner'.
app.artproject: Reverse query name for field 'owner' clashes with related field 'User.projects'. Add a related_name argument to the definition for 'owner'.
app.artproject: Accessor for field 'owner' clashes with related field 'User.projects'. Add a related_name argument to the definition for 'owner'.
app.artproject: Reverse query name for field 'owner' clashes with related field 'User.projects'. Add a related_name argument to the definition for 'owner'.

Same output for ResearchProject, the error gets printed twice for every model.

Is this by design or is a fix possible?
Some kind of workaround at the moment is defining the base model as not abstract, obviously at the cost of SQL overhead/performance.

[benkonrath]

I ran into the same problem on a project that I'm working on. I think it's by design. If it is in fact, it would be nice to get an error message indicating problem directly rather than just guessing.

@chrisglass Any thoughts?

[iwaszko]

I'd say it's not related to django_polymorphic. For some suggestions have a look here: https://docs.djangoproject.com/en/dev/topics/db/models/#be-careful-with-related-name

[vdboor]

Indeed, this is more a Django thing then a polymorphic option.
You can address it using the '%(class)' trick.