源码分析:
class ModelBackend:
    """
    Authenticates against settings.AUTH_USER_MODEL.
    """
    def authenticate(self, request, username=None, password=None, **kwargs):
        if username is None:
            username = kwargs.get(UserModel.USERNAME_FIELD)
        try:
            user = UserModel._default_manager.get_by_natural_key(username)
        except UserModel.DoesNotExist:
            # Run the default password hasher once to reduce the timing
            # difference between an existing and a nonexistent user (#20760).
            UserModel().set_password(password)
        else:
            if user.check_password(password) and self.user_can_authenticate(user):
                return user
通过查看源码我们可以看到Django默认的认证后端是判断用户的username和password这两个字段是否通过校验,但实际上,我们可能会有更多的登录需求,比如说,既可以通过用户名,也可以通过手机号或邮箱等登录,这时候我们可以重写authenticate()方法实现
# 以前使用username进行用户验证,现在修改成email|phone进行验证 多形式登录
from user.models import User
class EmailAuthBackend:
    def authenticate(self, request, username=None, password=None):
        try:
            user = User.objects.get(username=username)
        except Exception as e:
            user = None
        if not user:
            try:
                user = User.objects.get(email=username)
            except Exception as e:
                user = None
        if not user:
            try:
                user = User.objects.get(phone=username)
            except Exception as e:
                user = None
        if user and user.check_password(password):
            return user
        else:
            return None
    def get_user(self, user_id):
        try:
            return User.objects.get(pk=user_id)
        except User.DoesNotExist:
            return None
from django.contrib.auth.backends import ModelBackend
from user import models
from django.db.models import Q
class MultiformAuthBackend(ModelBackend):
    def authenticate(self, request, username=None, password=None, **kwargs):
        try:
            user = User.objects.get(Q(username=username) | Q(phone=username) | Q(email=username))
            if user is not None and user.check_password(password):
                return user
        except Exception as e:
            print(e)
# 自定义验证后端 多形式登录
# AUTHENTICATION_BACKENDS = [‘user.utils.EmailAuthBackend‘]
AUTHENTICATION_BACKENDS = [‘user.utils.MultiformAuthBackend‘]
其他类似链接参考:
【Django】创建用户,继承AbstractUser自定义用户模型类
【Django】自定义存储后端返回完整图片的URL链接
原文:https://www.cnblogs.com/tjw-bk/p/13935859.html