database - Django 用户和来自外部源的身份验证

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。 session 数据存储在缓存中(在我的开发服务器上，我使用 SQLite 数据库，所以这不是错误源)。我正在使用最新的 Django 1.1svn。

输入问题:我想使用Django自带的用户认证系统。

编写我自己的身份验证后端似乎很简单，但总是前提是你有一个本地数据库来保存用户。没有数据库，我的主要问题是持久性。

我尝试了以下方法(假设 datasource.get() 是一个返回某种字典的函数):

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

但是 MyUser 上故意缺少的 save() 方法似乎破坏了登录的 session 存储。

如果没有本地数据库，MyUser 应该是什么样子？

Answer 1

好吧，这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对其进行扩展。

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

然后用户:

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 []

呸! Django 真的不是为没有数据库的使用而设计的......