如何设置字段值的过期时间

Question

我有这样的型号User：

class User(AbstractBaseUser, PermissionsMixin):
    myfield_choices = (('foo', 'First value'), ('bar', 'Second value')
    myfield = CharField(choices=choices)
    
    objects = BaseUserManager()

我在字段myfield中设置了值foo。在我想在字段myfield中设置值bar 1天后，并且在该期限到期后，该值再次自动变为foo
如何设置过期时间？有本地django乐器吗？

Answer 1

我认为您对Django有点陌生，所以我建议您使用一种不基于任务队列的解决方案(如celery或dramatiq(。

为了清楚起见，让我们假设我们正在实现ban_user和unban_user机制。首先，我们必须更新User模型：

class User(AbstractBaseUser, PermissionsMixin):
    class BanStatus(models.TextChoices):
        ACTIVE = "ACTIVE", "ACTIVE"
        BANNED_FOR_DAY = "BANNED_FOR_DAY", "BANNED_FOR_DAY"
    ban_status = models.TextField("Ban status", choices=BanStatus.choices)
    banned_for_day_at = models.DateTimeField("Banned for day at", null=True)

然后我们必须实现精确的机制。我更喜欢在一些your-app-name/logic/ban_user.py文件中进行：

from django.utils import timezone
# And also an import of User.

def ban_user_for_day(user: User):
    user.ban_status = User.BanStatus.BANNED_FOR_DAY
    user.banned_for_day_at = timezone.now()
    user.save()

def revoke_ban_user_for_day(user: User):
    user.ban_status = User.BanStatus.ACTIVE
    user.banned_for_day_at = None
    user.save()

因此，我们可以从视图中调用ban_user_for_day。对于revoke_ban_user_for_day，组织调用它的最简单方法是Command，它可以定期调用，例如cron。您可以将其放置在your-app-name/management/commands/revoke_ban_user_for_day.py

from django.core.management import BaseCommand
from django.utils import timezone
# And also imports of User and revoke_ban_user_for_day.

class Command(BaseCommand):
    def handle(self, *args, **options):
        user_list_for_revoke = User.objects.filter(
            ban_status=User.BanStatus.ACTIVE,
            banned_for_day_at__lte=timezone.now() - timezone.timedelta(days=1)
        ).all()
        for user in user_list_for_revoke:
            revoke_ban_user_for_day(user)

仅此而已。如果您将此Command设置为每分钟运行一次，则User应取消联机和实际取消联机之间的延迟将不大于1分钟。