Django用户和外部源的身份验证

Question

我有一个Django应用程序,它完全从外部源(通过HTTP查询)获取数据.也就是说,我没有本地数据库的选项.会话数据存储在缓存中(在我的开发服务器上,我使用SQLite数据库,因此这不是错误源).我正在使用前沿的Django 1.1svn.

输入问题:我想为用户使用Django自己的身份验证系统.

编写我自己的身份验证后端似乎很简单,但总是在你有一个本地数据库保存用户的条件下.没有数据库我的主要问题是持久性.

我尝试了以下(假设这datasource.get()是一个返回某种dict的函数):

class ModelBackend (object):
    """Login backend."""

    def authenticate (self, username=None, password=None):
        """Check, if a given user/password combination is valid"""

        data = datasource.get ('login', username, password)
        if data and data['ok']:
            return MyUser (username=username)
        else:
            raise TypeError
            return None

    def get_user (self, username):
        """get data about a specific user"""

        try:
          data = datasource.get ('userdata', username)
          if data and data['ok']:
              return data.user
        except:
            pass
        return None


class MyUser (User):
    """Django user who isn't saved in DB"""

    def save (self):
        return None

但save()MyUser上故意丢失的方法似乎打破了登录的会话存储.

MyUser没有本地数据库应该怎么样？

Answer 1

好吧,它比我想象的要复杂得多.首先,从http://docs.djangoproject.com/en/dev/howto/auth-remote-user/开始,但您需要使用自己的后端和用户扩展它.

from django.contrib.auth.backends import RemoteUserBackend

class MyRemoteUserBackend (RemoteUserBackend):
    # Create a User object if not already in the database?
    create_unknown_user = False

    def get_user (self, user_id):
        user = somehow_create_an_instance_of (MyUser, user_id)
        return user

    def authenticate (self, **credentials):
        check_credentials ()
        user = somehow_create_an_instance_of (MyUser, credentials)
        return user

那么用户:

from django.contrib.auth.models import User

class MyUser (User):

    def save (self):
        """saving to DB disabled"""
        pass

    objects = None # we cannot really use this w/o local DB

    username = ""  # and all the other properties likewise.
                   # They're defined as model.CharField or similar,
                   # and we can't allow that

    def get_group_permissions (self):
        """If you don't make your own permissions module,
           the default also will use the DB. Throw it away"""
        return [] # likewise with the other permission defs

    def get_and_delete_messages (self):
        """Messages are stored in the DB. Darn!"""
        return []

唷!Django 真的不适合在没有数据库的情况下使用......

Answer 2

save您也可以断开调用该方法的信号，而不是覆盖该方法。这就是我在一些对用户数据库具有只读访问权限的应用程序中所做的事情。

# models.py (for instance)
from django.contrib.auth.models import update_last_login, user_logged_in
user_logged_in.disconnect(update_last_login)