Temporarily disable auto_now / auto_now_add

Question

I have a model like this:

class FooBar(models.Model):     createtime = models.DateTimeField(auto_now_add=True)     lastupdatetime = models.DateTimeField(auto_now=True) 

I want to overwrite the two date fields for some model instances (used when migrating data). The current solution looks like this:

for field in new_entry._meta.local_fields:     if field.name == "lastupdatetime":         field.auto_now = False     elif field.name == "createtime":         field.auto_now_add = False  new_entry.createtime = date new_entry.lastupdatetime = date new_entry.save()  for field in new_entry._meta.local_fields:     if field.name == "lastupdatetime":         field.auto_now = True     elif field.name == "createtime":         field.auto_now_add = True 

Is there a better solution?

Answer 1

I've recently faced this situation while testing my application. I needed to "force" an expired timestamp. In my case I did the trick by using a queryset update. Like this:

# my model class FooBar(models.Model):     title = models.CharField(max_length=255)     updated_at = models.DateTimeField(auto_now=True, auto_now_add=True)    # my tests foo = FooBar.objects.get(pk=1)  # force a timestamp lastweek = datetime.datetime.now() - datetime.timedelta(days=7) FooBar.objects.filter(pk=foo.pk).update(updated_at=lastweek)  # do the testing.