drf中的jwt使用與手動簽發token、校驗用戶

jwt認證

1）session存儲token，需要數據庫參與，耗服務器資源、低效
2）緩存存token，需要緩存參與，高效，不易集群
3）客戶端存token，服務器存簽發與交易token的算法，高效，易集群

drf-jwt使用：

安裝：djangorestframework-jwt
視圖類簽發token - username,password => token
認證類校驗token - token => user

jwt格式：基本信息(頭base64).用戶信息過期時間(載荷base64).所有信息+秘鑰(簽名HS256)

簽發token

源碼入口

# 前提：給一個局部禁用了所有 認證與權限 的視圖類發送用戶信息得到token，其實就是登錄接口

# 1）rest_framework_jwt.views.ObtainJSONWebToken 的 父類 JSONWebTokenAPIView 的 post 方法
#        接受有username、password的post請求
# 2）post方法將請求數據交給 rest_framework_jwt.serializer.JSONWebTokenSerializer 處理
#        完成數據的校驗，會走序列化類的 全局鈎子校驗規則，校驗得到登錄用戶並簽發token存儲在序列化對象中

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

def validate(self, attrs):
    # 賬號密碼字典
    credentials = {
        self.username_field: attrs.get(self.username_field),
        'password': attrs.get('password')
    }
    if all(credentials.values()):
        # 簽發token第1步：用賬號密碼得到user對象
        user = authenticate(**credentials)
        if user:
            if not user.is_active:
                msg = _('User account is disabled.')
                raise serializers.ValidationError(msg)
            # 簽發token第2步：通過user得到payload，payload包含着用戶信息與過期時間
            payload = jwt_payload_handler(user)
            # 在視圖類中，可以通過 序列化對象.object.get('user'或者'token') 拿到user和token 
            return {
                # 簽發token第3步：通過payload簽發出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)

根據源碼內容我們可以簡要的推導出手動簽發token的邏輯

# 1）通過username、password得到user對象
# 2）通過user對象生成payload：jwt_payload_handler(user) => payload
#        from rest_framework_jwt.serializers import jwt_payload_handler
# 3）通過payload簽發token：jwt_encode_handler(payload) => token
#        from rest_framework_jwt.serializers import jwt_encode_handler

校驗token

源碼入口

# 前提：訪問一個配置了jwt認證規則的視圖類，就需要提交認證字符串token，在認證類中完成token的校驗

# 1）rest_framework_jwt.authentication.JSONWebTokenAuthentication 的 父類 BaseJSONWebTokenAuthentication 的 authenticate 方法
#        請求頭拿認證信息jwt-token => 通過反爬小規則確定有用的token => payload => user

核心源碼：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`.
    """
    # 帶有反爬小規則的獲取token：前台必須按 "jwt token字符串" 方式提交
    # 校驗user第1步：從請求頭 HTTP_AUTHORIZATION 中拿token，並提取
    jwt_value = self.get_jwt_value(request)
    # 游客
    if jwt_value is None:
        return None
    # 校驗
    try:
        # 校驗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()
    # 校驗user第3步：token => payload
    user = self.authenticate_credentials(payload)

    return (user, jwt_value)

手動校驗token邏輯

# 1）從請求頭中獲取token
# 2）根據token解析出payload：jwt_decode_handler(token) => payloay
#        from rest_framework_jwt.authentication import jwt_decode_handler
# 3）根據payload解析出user：self.authenticate_credentials(payload) => user
#        繼承drf-jwt的BaseJSONWebTokenAuthentication，拿到父級的authenticate_credentials方法

案例：實現多方式登陸簽發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 = '用戶表'
        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的兩個函數： 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) 前台提交多種登錄信息都采用一個key，所以后台可以自定義反序列化字段進行對應
# 2) 序列化類要處理序列化與反序列化，要在fields中設置model綁定的Model類所有使用到的字段
# 3) 區分序列化字段與反序列化字段 read_only | write_only
# 4) 在自定義校驗規則中（局部鈎子、全局鈎子）校驗數據是否合法、確定登錄的用戶、根據用戶簽發token
# 5) 將登錄的用戶與簽發的token保存在序列化類對象中
class UserModelSerializer(serializers.ModelSerializer):
    # 自定義反序列字段：一定要設置write_only，只參與反序列化，不會與model類字段映射
    usr = serializers.CharField(write_only=True)
    pwd = serializers.CharField(write_only=True)
    class Meta:
        model = models.User
        fields = ['usr', 'pwd', 'username', 'mobile', 'email']
        # 系統校驗規則
        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')

        # 多方式登錄：各分支處理得到該方式下對應的用戶
        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()

        # 簽發：得到登錄用戶，簽發token並存儲在實例化對象中
        if user_obj and user_obj.check_password(pwd):
            # 簽發token，將token存放到 實例化類對象的token 名字中
            payload = jwt_payload_handler(user_obj)
            token = jwt_encode_handler(payload)
            # 將當前用戶與簽發的token都保存在序列化對象中
            self.user = user_obj
            self.token = token
            return attrs

        raise serializers.ValidationError({'data': '數據有誤'})

views.py

#實現多方式登陸簽發token：賬號、手機號、郵箱等登陸
# 1) 禁用認證與權限組件
# 2) 拿到前台登錄信息，交給序列化類
# 3) 序列化類校驗得到登錄用戶與token存放在序列化對象中
# 4) 取出登錄用戶與token返回給前台
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) 禁用認證與權限組件
    authentication_classes = []
    permission_classes = []
    def post(self, request, *args, **kwargs):
        # 2) 拿到前台登錄信息，交給序列化類，規則：賬號用usr傳，密碼用pwd傳
        user_ser = serializers.UserModelSerializer(data=request.data)
        # 3) 序列化類校驗得到登錄用戶與token存放在序列化對象中
        user_ser.is_valid(raise_exception=True)
        # 4) 取出登錄用戶與token返回給前台
        return APIResponse(token=user_ser.token, results=serializers.UserModelSerializer(user_ser.user).data)

    # "一根筋" 思考方式：所有邏輯都在視圖類中處理
    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='不可控錯誤')

案例：自定義認證反爬規則的認證類

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')

        # 自定義校驗規則：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已過期')
        except:
            raise AuthenticationFailed('非法用戶')
        # payload => user
        user = self.authenticate_credentials(payload)

        return (user, token)

    # 自定義校驗規則：auth token jwt，auth為前鹽，jwt為后鹽
    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
# 必須登錄后才能訪問 - 通過了認證權限組件
from rest_framework.permissions import IsAuthenticated
# 自定義jwt校驗規則
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})

admin使用自定義User表：新增用戶密碼密文

from django.contrib import admin
from . import models

# 自定義User表，admin后台管理，采用密文密碼
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)

群查接口各種篩選組件數據准備

models.py

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

    class Meta:
        db_table = 'api_car'
        verbose_name = '汽車表'
        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

# Car的群查接口
from rest_framework.generics import ListAPIView

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

urls.py

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

drf搜索過濾組件

views.py

from rest_framework.generics import ListAPIView

# 第一步：drf的SearchFilter - 搜索過濾
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 過濾類 們（全局配置用DEFAULT_FILTER_BACKENDS）
    filter_backends = [SearchFilter]

    # 第三步：SearchFilter過濾類依賴的過濾條件 => 接口：/cars/?search=...
    search_fields = ['name', 'price']
    # eg：/cars/?search=1，name和price中包含1的數據都會被查詢出

drf排序過濾組件

views.py

from rest_framework.generics import ListAPIView

# 第一步：drf的OrderingFilter - 排序過濾
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 過濾類 們（全局配置用DEFAULT_FILTER_BACKENDS）
    filter_backends = [OrderingFilter]

    # 第三步：OrderingFilter過濾類依賴的過濾條件 => 接口：/cars/?ordering=...
    ordering_fields = ['pk', 'price']
    # eg：/cars/?ordering=-price,pk，先按price降序，如果出現price相同，再按pk升序

drf基礎分頁組件

pahenations.py

from rest_framework.pagination import PageNumberPagination

class MyPageNumberPagination(PageNumberPagination):
    # ?page=頁碼
    page_query_param = 'page'
    # ?page=頁面 下默認一頁顯示的條數
    page_size = 3
    # ?page=頁面&page_size=條數 用戶自定義一頁顯示的條數
    page_size_query_param = 'page_size'
    # 用戶自定義一頁顯示的條數最大限制：數值超過5也只顯示5條
    max_page_size = 5

views.py

from rest_framework.generics import ListAPIView

class CarListAPIView(ListAPIView):
    # 如果queryset沒有過濾條件，就必須 .all()，不然分頁會出問題
    queryset = models.Car.objects.all()
    serializer_class = serializers.CarModelSerializer
    
    # 分頁組件 - 給視圖類配置分頁類即可 - 分頁類需要自定義，繼承drf提供的分頁類即可
    pagination_class = pagenations.MyPageNumberPagination