Post create instance code call in django models

Question

Hi folks,

Sorry for some crazy subj.

I'd like to override django models save method and call some additional code if the model instance is newly created. Sure I can use signals or check if the model have empty pk field and if yes, create temporary variable and later call a code:

Class EmailModel(models.Model):
    email = models.EmailField()

    def save(self, *args, **kwargs)
        is_new = self.pk is None
        super(EmailModel, self).save(*args, **kwargs)
        # Create necessary objects
        if is_new:
            self.post_create()

    def post_create(self):
          # do job, send mails
          pass

But I like to have some beautiful code and avoid using temporary variable in save method. So the question is: is it possible to find if the instance of model is newly created object just after super save_base parent method call?

I've checked django sources can't find how to do that in right way.

Thanks

We have related post

Answer 1

For real - signals are best approch in this case.

You could use post_save() signal and in the listener just check if the credit_set exist for current model instance and if not - create one. That would be my choice - there is no need to overdo such a simple task.

Of course if you really need to know exactly when the model was initiated (I doubt it) use post_init() signal. You don't need to override save() method just to set some additional variables. Just catch post_init() signal, or pre_save(), and just change/add what you want. IMHO there is no sense to override save() method and check if this is new instance or not - that's why the signals are there.