JWT认证

时间 2019-11-10 标签 jwt 认证

　　服务器不要存储token，token交给每个客户端本身存储，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）git

格式github

　　jwt token采用三段式：头部.载荷.签名算法

　　每一部分都是一个json字典加密形参的字符串django

　　头部和载荷采用的是base64可逆加密（前台后台均可以解密）json

　　签名采用hash256不可逆加密（后台校验采用碰撞校验）api

　　各部分字典的内容：服务器

　　　　头部：基础信息 - 公司信息、项目组信息、可逆加密采用的算法并发

　　　　载荷：有用但非私密的信息 - 用户可公开信息、过时时间ide

　　　　签名：头部+载荷+秘钥不可逆加密后的结果高并发

　　　　注：服务器jwt签名加密秘钥必定不能泄露

签发token：固定的头部信息加密.当前的登录用户与过时时间加密.头部+载荷+秘钥生成不可逆加密

校验token：头部可校验也能够不校验，载荷校验出用户与过时时间，头部+载荷+秘钥完成碰撞检测校验token是否被篡改

drf-jwt插件：https://github.com/jpadilla/django-rest-framework-jwt

安装： pip3 install djangorestframework-jwt

api/urls.py

from django.conf.urls import url
from . import views
from rest_framework_jwt.views import ObtainJSONWebToken,obtain_jwt_token
urlpatterns = [
    # url(r'^jogin', ObtainJSONWebToken.as_view()),
    url(r'^jogin', obtain_jwt_token),
    url(r'^user/detail/$', views.UserDetail.as_view()),
]
# 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

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
# 必须登陆后，才能访问， 经过认证权限组件
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})

签发token

　　前提：给一个局部禁用了全部认证与权限的视图类发送用户信息获得token，其实就是登陆接口

　　rest_framework_jwt.views.ObtainJSONWebToken 的父类 JSONWebTokenAPIView 的 post 方法，接受有username、password的post请求

　　post方法将请求数据交给 rest_framework_jwt.serializer.JSONWebTokenSerializer 处理，完成数据的校验，会走序列化类的全局钩子校验规则，校验获得登陆用户并签发token存储在序列化对象

核心源码：rest_framework_jwt.serializer.JSONWebTokenSerializer的validate(self, attrs)方法

def validate(self, attrs):
    # 帐号密码字典
    credentials = {
        self.username_field: attrs.get(self.username_field),
        'password': attrs.get('password')
    }
    if all(credentials.values()):
        # 签发token第1步：用帐号密码获得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：经过user获得payload，payload包含着用户信息与过时时间
            payload = jwt_payload_handler(user)
            # 在视图类中，能够经过 序列化对象.object.get('user'或者'token') 拿到user和token 
            return {
                # 签发token第3步：经过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)

手动签发token逻辑
　　经过username、password获得user对象，经过user对象生成payload：jwt_payload_handler(user) => payload，　　from rest_framework_jwt.serializers import jwt_payload_handler 经过payload签发token：jwt_encode_handler(payload) => token from rest_framework_jwt.serializers import jwt_encode_handler

校验token

　　前提：访问一个配置了jwt认证规则的视图类，就须要提交认证字符串token，在认证类中完成token的校验， rest_framework_jwt.authentication.JSONWebTokenAuthentication 的父类 BaseJSONWebTokenAuthentication 的 authenticate 方法，请求头拿认证信息jwt-token => 经过反爬小规则肯定有用的token => payload => user 　　

核心源码：rest_framework_jwt.authentication.BaseJSONWebTokenAuthentication的authenticate(self, request)方法

def authenticate(self, request):
    """
    Returns a two-tuple of `User` and token if a valid signature has been
    supplied using JWT-based authentication.  Otherwise returns `None`.
    """
    # 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)

手动校验token逻辑

　　从请求头中获取token，根据token解析出payload：jwt_decode_handler(token) => payloay， from rest_framework_jwt.authentication import jwt_decode_handler，根据payload解析出user：self.authenticate_credentials(payload) => user，继承drf-jwt的BaseJSONWebTokenAuthentication，拿到父级的authenticate_credentials方法

实现多方式登录签发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
from rest_framework_jwt.serializers import jwt_payload_handler
from rest_framework_jwt.serializers import jwt_encode_handler

# 前台提交多种登陆信息都采用一个key,因此后台能够自定义反序列化字段进行对应
# 序列化要处理序列化与反序列化，要在fields中绑定的Model类全部使用到的字段
# 区分序列化字段与反序列化字段 read_only | write_only
# 在自定义校验规则中，校验数据是否合法，肯定登陆用户，根据用户签发token
# 将登陆的用户与签发的token保存在序列化对象中

class UserModelSerializer(serializers.ModelSerializer):
    # 自定义反序列字段：必定要设置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')

        # 多方式登陆：各分支处理获得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：获得登陆用户，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

from rest_framework.views import APIView

from utils.response import APIResponse
# 必须登陆后，才能访问， 经过认证权限组件
from rest_framework.permissions import IsAuthenticated
from rest_framework_jwt.authentication import JSONWebTokenAuthentication
from .authentications import JWTAuthentication
class UserDetail(APIView):
    # authentication_classes = [JSONWebTokenAuthentication]
    authentication_classes = [JWTAuthentication]
    permission_classes = [IsAuthenticated]
    def get(self, request, *args, **kwargs):
        return APIResponse(results={'username': request.user.username})

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:
            payload = jwt_decode_handler(token)
        except jwt.ExpiredSignature:
            raise AuthenticationFailed('token 已过时')
        except:
            raise AuthenticationFailed('非法用户')
        user = self.authenticate_credentials(payload)
        return (user, token)
    # 自定义校验检测：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 utils.response import APIResponse
# 必须登陆后，才能访问， 经过认证权限组件
from rest_framework.permissions import IsAuthenticated
from rest_framework_jwt.authentication import JSONWebTokenAuthentication
from .authentications import JWTAuthentication
class UserDetail(APIView):
    # authentication_classes = [JSONWebTokenAuthentication]
    authentication_classes = [JWTAuthentication]
    permission_classes = [IsAuthenticated]
    def get(self, request, *args, **kwargs):
        return APIResponse(results={'username': request.user.username})

admin使用自定义User表：新增用户密码密文

from . import models
from django.contrib.auth.admin import UserAdmin
class MyUserAdmin(UserAdmin):
    add_fieldsets = (
        (
            None, {
                'classes': ('wide',),
                'fields': ('username', 'password1', 'password2', 'mobile', 'email'),
            })
    )
admin.site.register(models.User, MyUserAdmin)

群查接口各类筛选组件

urls.py

url(r'^cars/$', views.CarListAPIView.as_view()),

models.py

class Car(models.Model):
    name = models.CharField(max_length=16, unique=True, verbose_name='车名')
    price = models.DecimalField(max_digits=10, decimal_places=2, verbose_name='价格')
    brand = models.CharField(max_length=16, verbose_name='品牌')

    class Meta:
        db_table = 'api_car'
        verbose_name = '汽车表'
        verbose_name_plural = verbose_name

    def __str__(self):
        return self.name

admin.py

admin.site.register(models.Car)

serializers.py

class CarModelSerializer(serializers.ModelSerializer):
    class Meta:
        model = models.Car
        fields = ['name', 'price', 'brand']

views.py

from rest_framework.generics import ListAPIView

class CarListAPIView(ListAPIView):
    queryset = models.Car.objects.all()
    serializer_class = serializers.CarModelSerializer

drf搜索过滤组件

 from rest_framework.generics import ListAPIView

# 第一步：drf的SearchFilter - 搜索过滤
from rest_framework.filters import SearchFilter

class CarListAPIView(ListAPIView):
    queryset = models.Car.objects.all()
    serializer_class = serializers.CarModelSerializer

    # 第二步：局部配置 过滤类 们（全局配置用DEFAULT_FILTER_BACKENDS）
    filter_backends = [SearchFilter]

    # 第三步：SearchFilter过滤类依赖的过滤条件 => 接口：/cars/?search=...
    search_fields = ['name', 'price']
    # eg：/cars/?search=1，name和price中包含1的数据都会被查询出

drf排序过滤组件

from rest_framework.generics import ListAPIView

# 第一步：drf的OrderingFilter - 排序过滤
from rest_framework.filters import OrderingFilter

class CarListAPIView(ListAPIView):
    queryset = models.Car.objects.all()
    serializer_class = serializers.CarModelSerializer

    # 第二步：局部配置 过滤类 们（全局配置用DEFAULT_FILTER_BACKENDS）
    filter_backends = [OrderingFilter]

    # 第三步：OrderingFilter过滤类依赖的过滤条件 => 接口：/cars/?ordering=...
    ordering_fields = ['pk', 'price']
    # eg：/cars/?ordering=-price,pk，先按price降序，若是出现price相同，再按pk升序

drf基础分页组件

pahenations.py

from rest_framework.pagination import PageNumberPagination

class MyPageNumberPagination(PageNumberPagination):
    # ?page=页码
    page_query_param = 'page'
    # ?page=页面 下默认一页显示的条数
    page_size = 3
    # ?page=页面&page_size=条数 用户自定义一页显示的条数
    page_size_query_param = 'page_size'
    # 用户自定义一页显示的条数最大限制：数值超过5也只显示5条
    max_page_size = 5

views.py

from rest_framework.generics import ListAPIView
from . import pahenations

class CarListAPIView(ListAPIView):
    # 若是queryset没有过滤条件，就必须 .all()，否则分页会出问题
    queryset = models.Car.objects.all()
    serializer_class = serializers.CarModelSerializer
    
    # 分页组件 - 给视图类配置分页类便可 - 分页类须要自定义，继承drf提供的分页类便可
    pagination_class = pagenations.MyPageNumberPagination

drf偏移分页组件

pahenations.py

from rest_framework.pagination import LimitOffsetPagination
class MyLimitOffsetPagination(LimitOffsetPagination):
    # ?offset=从头偏移的条数&limit=要显示的条数
    limit_query_param = 'limit'
    offset_query_param = 'offset'
    # ?不传offset和limit默认显示前3条，只设置offset就是从偏移位日后再显示3条
    default_limit = 3
    # ?limit能够自定义一页显示的最大条数
    max_limit = 5

views.py

from rest_framework.generics import ListAPIView

class CarListAPIView(ListAPIView):
    # 若是queryset没有过滤条件，就必须 .all()，否则分页会出问题
    queryset = models.Car.objects.all()
    serializer_class = serializers.CarModelSerializer
    
    # 分页组件 - 给视图类配置分页类便可 - 分页类须要自定义，继承drf提供的分页类便可
    pagination_class = pagenations.MyLimitOffsetPagination

drf游标分页组件

pahenations.py

# 1）若是接口配置了OrderingFilter过滤器，那么url中必须传ordering
# 1）若是接口没有配置OrderingFilter过滤器，必定要在分页类中声明ordering按某个字段进行默认排序
from rest_framework.pagination import CursorPagination
class MyCursorPagination(CursorPagination):
    cursor_query_param = 'cursor'
    page_size = 3
    page_size_query_param = 'page_size'
    max_page_size = 5
    ordering = '-pk'

views.py

from rest_framework.generics import ListAPIView

class CarListAPIView(ListAPIView):
    # 若是queryset没有过滤条件，就必须 .all()，否则分页会出问题
    queryset = models.Car.objects.all()
    serializer_class = serializers.CarModelSerializer
    
    # 分页组件 - 给视图类配置分页类便可 - 分页类须要自定义，继承drf提供的分页类便可
    pagination_class = pagenations.MyCursorPagination

自定义过滤器

filters.py

# 自定义过滤器，接口：?limit=显示的条数
class LimitFilter:
    def filter_queryset(self, request, queryset, view):
        # 前台固定用 ?limit=... 传递过滤参数
        limit = request.query_params.get('limit')
        if limit:
            limit = int(limit)
            return queryset[:limit]
        return queryset

views.py

from rest_framework.generics import ListAPIView

class CarListAPIView(ListAPIView):
    # 若是queryset没有过滤条件，就必须 .all()，否则分页会出问题
    queryset = models.Car.objects.all()
    serializer_class = serializers.CarModelSerializer
    
    # 局部配置 过滤类 们（全局配置用DEFAULT_FILTER_BACKENDS）
    filter_backends = [LimitFilter]

过滤器插件：django-filter

安装　　pip3 install django-filter

filters.py

from django_filters.rest_framework.filterset import FilterSet
from . import models

# 自定义过滤字段
from django_filters import filters
class CarFilterSet(FilterSet):
    min_price = filters.NumberFilter(field_name='price', lookup_expr='gte')
    max_price = filters.NumberFilter(field_name='price', lookup_expr='lte')
    class Meta:
        model = models.Car
        fields = ['brand', 'min_price', 'max_price']
        # brand是model中存在的字段，通常都是能够用于分组的字段
        # min_price、max_price是自定义字段，须要本身自定义过滤条件

views.py

from django_filters.rest_framework import DjangoFilterBackend
from .filters import CarFilterSet

class CarListAPIView(ListAPIView):
    queryset = models.Car.objects.all()
    serializer_class = serializers.CarModelSerializer　　# django-filter过滤器插件使用　　filter_backends = [DjangoFilterBackend]