How to use foreignkey with different models in DJango

Question

I'm stack with this problem, and looking for some solution before asking this question here. Lets say I have a one Model that shares same field in different Models how can I achieve this that when I get the objects of those Models I can include that Model foreign key, I did try to achieve this using Generic Relation in DJango yet it didn't solve my issue.

here is the sample what I'm trying to achieve using Generic Relation:

Model1(models.Model):
 .. objects_on_this_model ..

Model2(models.Model):
 .. objects_on_this_model ...

# Now this is where the model I could save different models with same field shared
SameObjectModel(models.Model):
 content_type = models.ForeignKey(ContentType, on_delete=models.CASCADE)
 object_id = models.PositiveIntengerField()
 content_object = GenericForeignKey('content_type', 'object_id')
 .. objects_on_this_model .. # which is the field that has same field to use in different models

So when I try to get the objects from Model(n) how can I achieve or get the SameObjectModel?

I have this on my mind that I could do this:

Model(n).objects.prefetch_related('fk').all() 

Seems it is not a good idea, since I do not know where I should put the related_name since the foreign key is the content_type which is the model and there is the object_id represent the field primary_key.

Answer 1

On your Model(n)'s you can add a GenericRelation to SameObjectModel:

from django.contrib.contenttypes.fields import GenericRelation


class Model1(models.Model):
    sameobject = GenericRelation(SameObjectModel)

With this, it should be possible to use prefetch_related:

Model1.objects.prefetch_related('sameobject').all()