如何在Django中设置删除模型对象的时间限制？

Question

I want to set a time limit for object deletion in Django.

For example, the user can delete the object they submitted within 3 days; once the 3-days window is past, they can no longer delete the object. After that, only the superuser can delete it.

How can I achieve that? I tried lots of methods but none can do this...could someone help with the solutions?

Answer 1

1. store the "object creation" date in the instance to be processed. use DateTimeField with auto_now_add to set the field to now when the object is first created..
2. before deleting compare how many days have passed since the creation, use django signals pre-delete to trigger a check before executing the delete() and timedelta to calculate the age of the instance.
3. raise the correspondent error & catch when necessary

pro-tip: if you write a Model method obj.can_delete(self, user) you can write logic for 2 and 3 here instead having it across different parts of the app, then you can ask can_delete(user) first in order to present warnings or deactivate buttons, the user instance works for the conditional statement to allow only superusers to delete ignoring the age contitioning.

Answer 2

One solution would be to override the delete() method of the models and add a check there, maybe something like this:

from datetime import timedelta
from django.utils import timezone as tz

def delete(self, *args, **kwargs):
    user = kwargs['user']     # this may raise KeyError
    start_date = ...          # this probably would be a model field

    if user.is_superuser or (tz.now() < start_date + timedelta(days=3)):
        super().delete(*args, **kwargs)
    else:
        raise some error