Django:默认情况下执行不区分大小写的查找

Question

我需要username在使用Django Auth框架时默认执行不区分大小写的查询.

我尝试通过编写自定义子类Queryset 并重写该_filter_or_exclude方法来修复该问题,然后在User模型的自定义管理器中使用该子类 -

from django.db.models import Manager
from django.db.models.query import QuerySet
from django.contrib.auth.models import UserManager

class MyQuerySet(QuerySet):
    def _filter_or_exclude(self, negate, *args, **kwargs):
        if 'username' in kwargs:
            kwargs['username__iexact'] = kwargs['username']
            del kwargs['username']
        return super(MyQuerySet, self)._filter_or_exclude(negate, *args, **kwargs)

class MyUserManager(UserManager):
    def get_query_set(self):
        return MyQuerySet(self.model)

User.objects = MyUserManager()

但是这种方法不起作用,我在尝试时遇到了一个奇怪的错误User.objects.get(username='Foo').

任何帮助,将不胜感激.

更新:我包含了我得到的确切错误.

/usr/lib/python2.5/site-packages/django/db/models/query.py in get(self, *args, **kwargs)
    295         keyword arguments.
    296         """
--> 297         clone = self.filter(*args, **kwargs)
    298         num = len(clone)
    299         if num == 1:

/usr/lib/python2.5/site-packages/django/db/models/query.py in filter(self, *args, **kwargs)
    481         set.
    482         """
--> 483         return self._filter_or_exclude(False, *args, **kwargs)
    484 
    485     def exclude(self, *args, **kwargs):

/home/ghoseb/src/git/ocricket.git/ocricket/user/models.py in _filter_or_exclude(self, negate, *args, **kwargs)
     38             kwargs['username__iexact'] = kwargs['username']
     39             del kwargs['username']
---> 40         return super(MyQuerySet, self)._filter_or_exclude(negate, *args, **kwargs)
     41 
     42 class MyUserManager(UserManager):

/usr/lib/python2.5/site-packages/django/db/models/query.py in _filter_or_exclude(self, negate, *args, **kwargs)
    499             clone.query.add_q(~Q(*args, **kwargs))
    500         else:
--> 501             clone.query.add_q(Q(*args, **kwargs))
    502         return clone
    503 

/usr/lib/python2.5/django/db/models/sql/query.py in add_q(self, q_object, used_aliases)

/usr/lib/python2.5/django/db/models/sql/query.py in add_filter(self, filter_expr, connector, negate, trim, can_reuse, process_extras)

/usr/lib/python2.5/django/db/models/sql/query.py in get_meta(self)

<type 'exceptions.AttributeError'>: 'NoneType' object has no attribute '_meta'

更新:顺便说一句,我只是想提一下,当我将我的_filter_or_exclude方法中的逻辑复制到实际的QuerySet类中时,它可以完美地工作.

Answer 1

你不想搞乱Django类的内部功能.这种方式将来会遇到每次升级的麻烦.

如果要更改人员身份验证的方式,请编写自定义身份验证后端.

这是两个食谱.

http://www.davidcramer.net/code/224/logging-in-with-email-addresses-in-django.html

http://www.djangosnippets.org/snippets/577/

这两个人都是电子邮件而不是用户名.使用不区分大小写的查询而不是电子邮件查询并不难.

Answer 2

不能通过简单的属性分配 ( User.objects = MyManager()) 将管理器添加到类中。查看 ModelBase 元类 (db/models/base.py)，了解当您对 Model 进行子类化时，幕后为您做了什么。

您应该能够使其与User.add_to_class('objects', MyManager()). 或者，您可以创建User 的代理子类并在其中添加管理器。