JWT自定义校验规则与生成、用户多种方式登陆、搜索过滤组件，排序组件，分页组件

# 自定义校验token规则
1.视图类

from .authentications import JWTAuthentication

class UserDetail1(APIView):
    permission_classes = [IsAuthenticated]  # 必须登录
    authentication_classes = [JWTAuthentication]  # jwt用户token自定义登陆认证规则

    def get(self, request, *args, **kwargs):
        return APIResponse(results={'username': request.user.username})

2.自定义token规则，在api生成一个authentications.py认证文件

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')

        # 自定义规则 ：auth token jwt，调用下面规则方法
        token = self.parse_jwt_token(jwt_token)

        # 如果没有值，无法校验
        if token is None:
            return None

        try:
            # token =>payload  反向解析出payload
            payload = jwt_decode_handler(token)
        except jwt.ExpiredSignature:  # 判断是否过期
            raise AuthenticationFailed('token已过期')
        except:
            raise AuthenticationFailed('非法用户')
        user = self.authenticate_credentials(payload) # 根据payload解析出user

        return (user, token)

    # 自定义校验规则：auth token jwt ,auth为前言，jwt为后缀
    def parse_jwt_token(self, jw_token):
        tokens = jw_token.split()
        if len(tokens) != 3 or tokens[0].lower() != 'auth' or tokens[2].lower() != 'jwt':
            return None
        # 把token核心内容返回进行校验
        return tokens[1]

# 自定义 drf-jwt 配置

import datetime
JWT_AUTH = {
    # user => payload
    'JWT_PAYLOAD_HANDLER':
        'rest_framework_jwt.utils.jwt_payload_handler',
    # payload => token
    'JWT_ENCODE_HANDLER':
        'rest_framework_jwt.utils.jwt_encode_handler',
    # token => payload
    'JWT_DECODE_HANDLER':
        'rest_framework_jwt.utils.jwt_decode_handler',
    # token过期时间
    'JWT_EXPIRATION_DELTA': datetime.timedelta(days=7),
    # token刷新的过期时间
    'JWT_REFRESH_EXPIRATION_DELTA': datetime.timedelta(days=7),
    # 反爬小措施前缀
    'JWT_AUTH_HEADER_PREFIX': 'JWT',
}

实现多种方式登录签发token:比如 -账号、手机号、邮箱等登录：
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.序列化校验得到登陆用户与token存放在序列化对象中
4.取出登陆用户与token返回给前台
"""

from .serializers import UserModelSerializer

# 1.视图类

class LoginAPIView(APIView):
    authentication_classes = []  # 禁用认证
    permission_classes = []  # 禁用权限

    def post(self, request, *args, **kwargs):
        user_ser = UserModelSerializer(data=request.data)  # 反序列化进行校验
        # 校验通过，如果没有报异常
        user_ser.is_valid(raise_exception=True)

        # 正常登陆，把生成的token返回给前端
        return APIResponse(token=user_ser.token, results=UserModelSerializer(user_ser.user).data)
  

#2. 序列化类，进行校验，生成token发送出去

from rest_framework import serializers
from . import models
import re

from rest_framework_jwt.serializers import jwt_payload_handler, jwt_encode_handler

class UserModelSerializer(serializers.ModelSerializer):
    # 自定义反序列化字段：一定要设置write_only,值参与反序列化，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 = {
            # 'usr': {
                # 'required': True,  # 必须校验
            #     'min_length': 3,
            #     'error_messages': {
            #         'required': '必须填写，你个铺盖',
            #         'min_length': '太短楼！',
            #     }
            # },
            'username': {
                'read_only': True
            },
            'mobile': {
                'read_only': True
            },
            'email': {
                'read_only': True
            }

        }

    # 全局钩子，attrs里面是通过校验的
    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()

        if user_obj and user_obj.check_password(pwd):
            # 签发生成token，将token存放到实例化对象的中
            payload = jwt_payload_handler(user_obj)  # 把头部，和载荷过期时间,user对象，生成payload
            token = jwt_encode_handler(payload)  # 把头部，载荷，和秘=秘钥经过加密生成token
            self.token = token  # 把token赋值到对象中
            self.user = user_obj
            print(token)
            return attrs
        raise serializers.ValidationError({'data': '数据提供有误'})

 
搜索过滤，排序，分页：

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

# 1.drf的SearchFilter - 搜索过滤
from rest_framework.filters import SearchFilter

# 2.drf的OrderingFilter - 排序过滤
from rest_framework.filters import OrderingFilter

# 3.drf的分页类 - 自定义
from . import pagenations

class CarListAPIView(ListAPIView):
    permission_classes = []  # 权限取消
    authentication_classes = []  # 认证取消

    queryset = models.Car.objects.all()
    serializer_class = CarModelSerializer

    # 局部配置 过滤类 们（全局配置用DEFAULT_FILTER_BACKENDS）
    filter_backends = [SearchFilter,OrderingFilter]

    # SearchFilter过滤类依赖的过滤条件 => 接口：/cars/?search=...
    search_fields = ['name', 'price']

    # OrderingFilter过滤类依赖的过滤条件 => 接口：/cars/?ordering=...,正是升序，-则是降序
    ordering_fields = ['pk', 'price']
    # eg：/cars/?ordering=-price,pk，先按price降序，如果出现price相同，再按pk升序

    pagination_class = pagenations.MyPageNumberPagination

 
 # 自定义分页类

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'

    max_page_size = 5