通过OneToOneField自定义删除模型和关联模型

Question

我正在重写Django的delete_selected管理员操作。我有一个通过OneToOneField与另一个模型（Party）关联的模型（Person），并且delete_selected仅删除原始模型，而不删除相关模型中的数据，从而在我的数据库中留下“虚影行”。看起来像这本身可能表明我的代码存在问题，因为我的假设是delete()函数会级联删除相关模型。

无论如何，麻烦的是，我的自定义delete()函数首先删除Party，然后Person的OneToOneField为空并引发错误。想法？

这里是我的模型：

class Party(models.Model): 
    name = models.CharField(max_length=100) 
    ... 

class Person(models.Model): 
    party = models.OneToOneField(Party, editable=False) 
    firstName=models.CharField(max_length=60) 
    lastName=models.CharField(max_length=60) 

    def delete(self): 
     self.party.delete() 
     self.delete() 

我的管理员：

class PersonAdmin(admin.ModelAdmin): 
    actions=['really_delete_selected'] 

    def get_actions(self, request): 
     actions = super(PersonAdmin, self).get_actions(request) 
     del actions['delete_selected'] 
     return actions 

    def really_delete_selected(self, request, queryset): 
     for obj in queryset: 
      obj.delete() 

     if queryset.count() == 1: 
      message_bit = "1 person was" 
     else: 
      message_bit = "%s people were" % queryset.count() 
     self.message_user(request, "%s successfully deleted." % message_bit) 
    really_delete_selected.short_description = "Delete selected entries" 
    ... 

错误：

AssertionError at /admin/common/person/ 
Party object can't be deleted because its id attribute is set to None. 

Answer 1

我不知道为什么这样的作品，但它确实...

我改变了我的模型delete()功能：

def delete(self): 
    d = self.party.id 
    Party.objects.get(id__exact=d).delete() 

我想这基本上是做什么@Furb eenator建议，通过删除Party中正确的行，该级联删除了Person中的正确行。在黑暗中随意拍摄三张欢呼声，有时会起作用，呃？

Answer 2

Python使用缩进它的语义分析。您的def delete(self):没有正确缩进，因此它不覆盖原生的delete（）方法。它应该在班级Person的缩进级别下。就像这样：

class Party(models.Model): 
    name = models.CharField(max_length=100) 
    ... 

class Person(models.Model): 
    party = models.OneToOneField(Party, editable=False) 
    firstName=models.CharField(max_length=60) 
    lastName=models.CharField(max_length=60) 

    def delete(self): 
     self.party.delete() 
     self.delete() 

同样是你的管理部分的真实的，它应缩进这样：

class PersonAdmin(admin.ModelAdmin): 
    actions=['really_delete_selected'] 

    def get_actions(self, request): 
     actions = super(PersonAdmin, self).get_actions(request) 
     del actions['delete_selected'] 
     return actions 

    def really_delete_selected(self, request, queryset): 
     for obj in queryset: 
      obj.delete() 

     if queryset.count() == 1: 
      message_bit = "1 person was" 
     else: 
      message_bit = "%s people were" % queryset.count() 

     self.message_user(request, "%s successfully deleted." % message_bit) 
     really_delete_selected.short_description = "Delete selected entries" 
     ...