Can Django automatically create a related one-to-one model?

django django-models models
vagabond picture vagabond · Oct 30, 2009 · Viewed 25.1k times · Source

I have two models in different apps: modelA and modelB. They have a one-to-one relationship. Is there a way django can automatically create and save ModelB when modelA is saved?

class ModelA(models.Model):
    name = models.CharField(max_length=30)

class ModelB(models.Model):
    thing = models.OneToOneField(ModelA, primary_key=True)
    num_widgets = IntegerField(default=0)

When I save a new ModelA I want a entry for it to be saved automatically in ModelB. How can I do this? Is there a way to specify that in ModelA? Or is this not possible, and I would just need to create and save ModelB in the view?

Edited to say the models are in different apps.

Answer

John Paulett picture John Paulett · Oct 30, 2009

Take a look at the AutoOneToOneField in django-annoying. From the docs:

from annoying.fields import AutoOneToOneField

class MyProfile(models.Model):
    user = AutoOneToOneField(User, primary_key=True)
    home_page = models.URLField(max_length=255)
    icq = models.CharField(max_length=255)

(django-annoying is a great little library that includes gems like the render_to decorator and the get_object_or_None and get_config functions)

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