抽象Django模型经理

Question

我这里缺乏Python元编程知识.假设我有以下内容:

class OwnCompanyManager(models.Manager):
    """Only companies of this user"""
    def get_queryset(self, user):
        if user.is_superuser:
            return super(OwnCompanyManager, self).get_queryset()
        return super(OwnCompanyManager, self).get_queryset().filter(
            companyuser__user=user)


class OwnPublisherManager(models.Manager):
    """Only publishers of this user's company"""
    def get_queryset(self, user):
        if user.is_superuser:
            return super(OwnPublisherManager, self).get_queryset()
        return super(OwnPublisherManager, self).get_queryset().filter(
            company__companyuser__user=user)

class Company(models.Model):
    name = models.CharField(max_length=45)

    objects = models.Manager()
    own = OwnCompanyManager()


class Publisher(models.Model):
    company = models.ForeignKey(Company)
    allow_latest_dev = models.BooleanField(default=False)
    domains_blocked = models.BooleanField(default=False)

    objects = models.Manager()
    own = OwnPublisherManager()

我还有很多.我不喜欢复制粘贴样板Own(Publisher|Company|Etcetra)Manager).正如您所见,唯一的变化是在过滤器中.

我怎样才能提取Own(InsertModelNameHere)Manager和使用它Company,Publisher和其他车型？我想在管理器定义中指定过滤器kwargs.

Answer 1

这里不需要元编程或任何特别聪明的东西.您只需要提取更改的位.在这种情况下,它只是以下参数filter:您可以使用参数传递的字典形式,并将过滤器作为字符串存储在类属性中.

class AbstractManager(models.Manager):
    def get_queryset(self, user):
        if user.is_superuser:
            return super(AbstractManager, self).get_queryset()
        return super(AbstractManager, self).get_queryset().filter(**{self.filter: user})

class OwnCompanyManager(AbstractManager):
    filter = "companyuser__user"

class OwnPublisherManager(AbstractManager):
    filter = "company__companyuser__user"