django - 如果我创建 MyFile 对象，将自动创建 Document 对象

Question

如何创建这样的东西：

如果我创建MyFile对象，Document对象将自动创建。（rootfile应该ForeignKey是MyFile）

class MyFile(models.Model):
    user = models.ForeignKey(User)
    path = models.FileField(upload_to="files")

class Document(models.Model):
    rootfile = models.ForeignKey(MyFile)
    user = models.ForeignKey(User,related_name='doc_owner')
    title = models.CharField(max_length=255)
    description = models.TextField()
    content = models.TextField()

Answer 1

使用post_save()信号MyFile，如果它是新的，也创建Document对象。

@receiver(post_save, sender=MyFile)
def my_handler(sender, **kwargs):
    if kwargs['created']:
        #create document object appropriately.
        document = Document()
        document.rootfile = kwargs['instance']
        document.save()