python - 暂时禁用 auto_now/auto_now_add

Question

我有这样一个模型:

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

我想覆盖某些模型实例的两个日期字段(在迁移数据时使用)。当前的解决方案如下所示:

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

有没有更好的解决方案？

Answer 1

我最近在测试我的应用程序时遇到了这种情况。我需要“强制”过期的时间戳。就我而言，我通过使用查询集更新来解决问题。像这样:

# 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.