八、商品详情页功能

class GoodsListViewSet(mixins.ListModelMixin, mixins.RetrieveModelMixin,viewsets.GenericViewSet):

#轮播图
class GoodsImageSerializer(serializers.ModelSerializer):
    class Meta:
        model = GoodsImage
        fields = ("image",)

#商品列表页
class GoodsSerializer(serializers.ModelSerializer):
    #覆盖外键字段
    category = CategorySerializer()
    #images是数据库中设置的related_name="images"，把轮播图嵌套进来
    images = GoodsImageSerializer(many=True)
    class Meta:
        model = Goods
        fields = '__all__'

    class Meta:
        model = Goods
        fields = ['pricemin', 'pricemax','is_hot']

# user_operation/serializers.py

from rest_framework import serializers
from user_operation.models import UserFav
from rest_framework.validators import UniqueTogetherValidator

class UserFavSerializer(serializers.ModelSerializer):
    #获取当前登录的用户
    user = serializers.HiddenField(
        default=serializers.CurrentUserDefault()
    )
    class Meta:
        #validate实现唯一联合，一个商品只能收藏一次
        validators = [
            UniqueTogetherValidator(
                queryset=UserFav.objects.all(),
                fields=('user', 'goods'),
                #message的信息可以自定义
                message="已经收藏"
            )
        ]
        model = UserFav
        #收藏的时候需要返回商品的id，因为取消收藏的时候必须知道商品的id是多少
        fields = ("user", "goods",'id')

# user_operaton/views.py

from rest_framework import viewsets
from rest_framework import mixins
from .models import UserFav
from .serializers import UserFavSerializer

class UserFavViewset(viewsets.GenericViewSet, mixins.ListModelMixin, mixins.CreateModelMixin, mixins.DestroyModelMixin):
    '''
    用户收藏
    '''
    queryset = UserFav.objects.all()
    serializer_class = UserFavSerializer

# 配置用户收藏的url
router.register(r'userfavs', UserFavViewset, base_name="userfavs")

# utils/permissions.py

from rest_framework import permissions

class IsOwnerOrReadOnly(permissions.BasePermission):
    """
    Object-level permission to only allow owners of an object to edit it.
    Assumes the model instance has an `owner` attribute.
    """

    def has_object_permission(self, request, view, obj):
        # Read permissions are allowed to any request,
        # so we'll always allow GET, HEAD or OPTIONS requests.
        if request.method in permissions.SAFE_METHODS:
            return True

        # Instance must have an attribute named `owner`.
        #obj相当于数据库中的model，这里要把owner改为我们数据库中的user
        return obj.user == request.user

# user_operaton/views.py

from rest_framework import viewsets
from rest_framework import mixins
from .models import UserFav
from .serializers import UserFavSerializer
from rest_framework.permissions import IsAuthenticated
from utils.permissions import IsOwnerOrReadOnly
from rest_framework_jwt.authentication import JSONWebTokenAuthentication
from rest_framework.authentication import SessionAuthentication

class UserFavViewset(viewsets.GenericViewSet, mixins.ListModelMixin, mixins.CreateModelMixin, mixins.DestroyModelMixin):
    '''
    用户收藏
    '''
    serializer_class = UserFavSerializer
    #permission是用来做权限判断的
    # IsAuthenticated：必须登录用户；IsOwnerOrReadOnly：必须是当前登录的用户
    permission_classes = (IsAuthenticated,IsOwnerOrReadOnly)
    #auth使用来做用户认证的
    authentication_classes = (JSONWebTokenAuthentication,SessionAuthentication)
    #搜索的字段
    lookup_field = 'goods_id'

    def get_queryset(self):
        #只能查看当前登录用户的收藏，不会获取所有用户的收藏
        return UserFav.objects.filter(user=self.request.user)

//收藏
export const addFav = params => { return axios.post(`${local_host}/userfavs/`, params) }

//取消收藏
export const delFav = goodsId => { return axios.delete(`${local_host}/userfavs/`+goodsId+'/') }

export const getAllFavs = () => { return axios.get(`${local_host}/userfavs/`) }

//判断是否收藏
export const getFav = goodsId => { return axios.get(`${local_host}/userfavs/`+goodsId+'/') }