[Fixed]-Django ORM and pre_init signal

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1👍

✅

The problem is that pre_init signal doesn’t take instance parameter, so you are editing actual class (sender). Try using post_init signal which takes instance parameter, so you can change it:

def init_my_parent(sender, instance, *args, **kwargs):
    if not hasattr(instance,'child1'): 
        instance.child1 = MyChild1()
        instance.child1.save()
    if not hasattr(instance,'child2'): 
        instance.child2 = MyChild2()
        instance.child2.save()

signals.post_init.connect(init_my_parent, sender=MyParent)
👤Domen Blenkuš

0👍

class MyChild1(models.Model):
    attr1 = models.CharField(default='default value', max_length=100)

class MyChild2(models.Model):
    pass

class MyParent(models.Model):
    child1 = models.ForeignKey(MyChild1)
    child2 = models.ForeignKey(MyChild2

using class instead of def, then it is going to be fine.

👤Lawes

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