DRF ---- JWT
目录
JWT
jwt认证的优点:
服务器不要存储token，token交给每一个客户端自己存储，服务器压力小
服务器存储的是 签发和校验token 两段算法，签发认证的效率高
算法完成各集群服务器同步成本低，路由项目完成集群部署（适应高并发）
1 . 工作原理
2）每一部分都是一个json字典加密形参的字符串
3）头部和载荷采用的是base64可逆加密（前台后台都可以解密）
4）签名采用hash256不可逆加密（后台校验采用碰撞校验）
5）各部分字典的内容：
头部：基础信息 - 公司信息、项目组信息、可逆加密采用的算法
载荷：有用但非私密的信息 - 用户可公开信息、过期时间
签名：头部+载荷+秘钥 不可逆加密后的结果
注：服务器jwt签名加密秘钥一定不能泄露
签发token：固定的头部信息加密.当前的登陆用户与过期时间加密.头部+载荷+秘钥生成不可逆加密
校验token：头部可校验也可以不校验，载荷校验出用户与过期时间，头部+载荷+秘钥完成碰撞检测校验token是否被篡改
2 . drf-jwt
下载
https://github.com/jpadilla/django-rest-framework-jwt
安装
pip install djangorestframework-jwt
使用
官方接口文档
https://jpadilla.github.io/django-rest-framework-jwt/
模块不需要注册 因为没有涉及到数据库的映射
提供了view.py 有 4 个类 分别为:
class JSONWebTokenAPIView(APIView):
class ObtainJSONWebToken(JSONWebTokenAPIView): # 获得token 基于权限六表的
class RefreshJSONWebToken(JSONWebTokenAPIView): # 刷新token
class VerifyJSONWebToken(JSONWebTokenAPIView): # 校验token
# 三个函数
obtain_jwt_token = ObtainJSONWebToken.as_view()
refresh_jwt_token = RefreshJSONWebToken.as_view()
verify_jwt_token = VerifyJSONWebToken.as_view()
# ObtainJSONWebToken 视图类就是通过 username 和 password 得到 user 对象然后签发 token
from rest_framework_jwt.views import ObtainJSONWebToken, obtain_jwt_token
urlpatterns = [
url(r'^jogin/$', ObtainJSONWebToken.as_view()), # 可替换成下面的 里面有post方法
url(r'^jogin/$', obtain_jwt_token),
]
认证 - 校验token：全局或局部配置drf-jwt的认证类 JSONWebTokenAuthentication
from rest_framework.views import APIView
from utils.response import APIResponse
# 必须登录后才能访问 - 通过了认证权限组件
from rest_framework.permissions import IsAuthenticated
from rest_framework_jwt.authentication import JSONWebTokenAuthentication
class UserDetail(APIView):
authentication_classes = [JSONWebTokenAuthentication] # jwt-token校验request.user
permission_classes = [IsAuthenticated] # 结合权限组件筛选掉游客
def get(self, request, *args, **kwargs):
return APIResponse(results={'username': request.user.username})
# 路由
url(r'^user/detail/$', views.UserDetail.as_view()),
# 接口：/api/user/detail/
# 认证信息：必须在请求头的 Authorization 中携带 "jwt 后台签发的token" 格式的认证字符串
3.签发token
核心源码rest_framework_jwt.serializer.JSONWebTokenSerializer的validate(self, attrs)方法
def validate(self, attrs):
# 账号密码字典
credentials = {
self.username_field: attrs.get(self.username_field),
'password': attrs.get('password')
}
if all(credentials.values()):
# 签发token第1步：用账号密码得到user对象
user = authenticate(**credentials)
if user:
if not user.is_active:
msg = _('User account is disabled.')
raise serializers.ValidationError(msg)
# 签发token第2步：通过user得到payload，payload包含着用户信息与过期时间
payload = jwt_payload_handler(user)
# 在视图类中，可以通过 序列化对象.object.get('user'或者'token') 拿到user和token
return {
# 签发token第3步：通过payload签发出token
'token': jwt_encode_handler(payload),
'user': user
}
else:
msg = _('Unable to log in with provided credentials.')
raise serializers.ValidationError(msg)
else:
msg = _('Must include "{username_field}" and "password".')
msg = msg.format(username_field=self.username_field)
raise serializers.ValidationError(msg)
jwt_payload_handler
jwt_encode_handler
1）通过username、password得到user对象
2）通过user对象生成payload：jwt_payload_handler(user) => payload
# from rest_framework_jwt.serializers import jwt_payload_handler
3）通过payload签发token：jwt_encode_handler(payload) => token
# from rest_framework_jwt.serializers import jwt_encode_handler
4.校验token
核心源码：rest_framework_jwt.authentication.BaseJSONWebTokenAuthentication的authenticate(self, request)方法
jwt_decode_handler
def authenticate(self, request):
# 带有反爬小规则的获取token：前台必须按 "jwt token字符串" 方式提交
# 校验user第1步：从请求头 HTTP_AUTHORIZATION 中拿token，并提取
jwt_value = self.get_jwt_value(request)
# 游客
if jwt_value is None:
return None
# 校验
try:
# 校验user第2步：token => payload
payload = jwt_decode_handler(jwt_value)
except jwt.ExpiredSignature:
msg = _('Signature has expired.')
raise exceptions.AuthenticationFailed(msg)
except jwt.DecodeError:
msg = _('Error decoding signature.')
raise exceptions.AuthenticationFailed(msg)
except jwt.InvalidTokenError:
raise exceptions.AuthenticationFailed()
# 校验user第3步：token => payload
user = self.authenticate_credentials(payload)
return (user, jwt_value)
5.案例：实现多方式登陆签发token
models.py
from django.db import models
from django.contrib.auth.models import AbstractUser
class User(AbstractUser):
mobile = models.CharField(max_length=11, unique=True)
class Meta:
db_table = 'api_user'
verbose_name = '用户表'
verbose_name_plural = verbose_name
def __str__(self):
return self.username
serializers.py
from rest_framework import serializers
from . import models
import re
# 拿到前台token的两个函数： user => payload => token
# from rest_framework_jwt.settings import api_settings
# jwt_payload_handler = api_settings.JWT_PAYLOAD_HANDLER
# jwt_encode_handler = api_settings.JWT_ENCODE_HANDLER
from rest_framework_jwt.serializers import jwt_payload_handler
from rest_framework_jwt.serializers import jwt_encode_handler
# 1) 前台提交多种登录信息都采用一个key，所以后台可以自定义反序列化字段进行对应
# 2) 序列化类要处理序列化与反序列化，要在fields中设置model绑定的Model类所有使用到的字段
# 3) 区分序列化字段与反序列化字段 read_only | write_only
# 4) 在自定义校验规则中（局部钩子、全局钩子）校验数据是否合法、确定登录的用户、根据用户签发token
# 5) 将登录的用户与签发的token保存在序列化类对象中
class UserModelSerializer(serializers.ModelSerializer):
# 自定义反序列字段：一定要设置write_only，只参与反序列化，不会与model类字段映射
usr = serializers.CharField(write_only=True)
pwd = serializers.CharField(write_only=True)
class Meta:
model = models.User
fields = ['usr', 'pwd', 'username', 'mobile', 'email']
# 系统校验规则
extra_kwargs = {
'username': {
'read_only': True
},
'mobile': {
'read_only': True
},
'email': {
'read_only': True
},
}
def validate(self, attrs):
usr = attrs.get('usr')
pwd = attrs.get('pwd')
# 多方式登录：各分支处理得到该方式下对应的用户
if re.match(r'.+@.+', usr):
user_query = models.User.objects.filter(email=usr)
elif re.match(r'1[3-9][0-9]{9}', usr):
user_query = models.User.objects.filter(mobile=usr)
else:
user_query = models.User.objects.filter(username=usr)
user_obj = user_query.first()
# 签发：得到登录用户，签发token并存储在实例化对象中
if user_obj and user_obj.check_password(pwd):
# 签发token，将token存放到 实例化类对象的token 名字中
payload = jwt_payload_handler(user_obj)
token = jwt_encode_handler(payload)
# 将当前用户与签发的token都保存在序列化对象中
self.user = user_obj
self.token = token
return attrs
raise serializers.ValidationError({'data': '数据有误'})
views.py
#实现多方式登陆签发token：账号、手机号、邮箱等登陆
# 1) 禁用认证与权限组件
# 2) 拿到前台登录信息，交给序列化类
# 3) 序列化类校验得到登录用户与token存放在序列化对象中
# 4) 取出登录用户与token返回给前台
import re
from . import serializers, models
from utils.response import APIResponse
from rest_framework_jwt.serializers import jwt_payload_handler
from rest_framework_jwt.serializers import jwt_encode_handler
class LoginAPIView(APIView):
# 1) 禁用认证与权限组件
authentication_classes = []
permission_classes = []
def post(self, request, *args, **kwargs):
# 2) 拿到前台登录信息，交给序列化类，规则：账号用usr传，密码用pwd传
user_ser = serializers.UserModelSerializer(data=request.data)
# 3) 序列化类校验得到登录用户与token存放在序列化对象中
user_ser.is_valid(raise_exception=True)
# 4) 取出登录用户与token返回给前台
return APIResponse(token=user_ser.token, results=serializers.UserModelSerializer(user_ser.user).data)
# "一根筋" 思考方式：所有逻辑都在视图类中处理
def my_post(self, request, *args, **kwargs):
usr = request.data.get('usr')
pwd = request.data.get('pwd')
if re.match(r'.+@.+', usr):
user_query = models.User.objects.filter(email=usr)
elif re.match(r'1[3-9][0-9]{9}', usr):
user_query = models.User.objects.filter(mobile=usr)
else:
user_query = models.User.objects.filter(username=usr)
user_obj = user_query.first()
if user_obj and user_obj.check_password(pwd):
payload = jwt_payload_handler(user_obj)
token = jwt_encode_handler(payload)
return APIResponse(results={'username': user_obj.username}, token=token)
return APIResponse(data_msg='不可控错误')
6.案例：自定义认证反爬规则的认证类
authentications.py
import jwt
from rest_framework_jwt.authentication import BaseJSONWebTokenAuthentication
from rest_framework_jwt.authentication import jwt_decode_handler
from rest_framework.exceptions import AuthenticationFailed
class JWTAuthentication(BaseJSONWebTokenAuthentication):
def authenticate(self, request):
jwt_token = request.META.get('HTTP_AUTHORIZATION')
# 自定义校验规则：auth token jwt
token = self.parse_jwt_token(jwt_token)
if token is None:
return None
try:
# token => payload
payload = jwt_decode_handler(token)
except jwt.ExpiredSignature:
raise AuthenticationFailed('token已过期')
except:
raise AuthenticationFailed('非法用户')
# payload => user
user = self.authenticate_credentials(payload)
return (user, token)
# 自定义校验规则：auth token jwt，auth为前盐，jwt为后盐
def parse_jwt_token(self, jwt_token):
tokens = jwt_token.split()
if len(tokens) != 3 or tokens[0].lower() != 'auth' or tokens[2].lower() != 'jwt':
return None
return tokens[1]
views.py
from rest_framework.views import APIView
from utils.response import APIResponse
# 必须登录后才能访问 - 通过了认证权限组件
from rest_framework.permissions import IsAuthenticated
# 自定义jwt校验规则
from .authentications import JWTAuthentication
class UserDetail(APIView):
authentication_classes = [JWTAuthentication]
permission_classes = [IsAuthenticated]
def get(self, request, *args, **kwargs):
return APIResponse(results={'username': request.user.username})
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