生鲜超市项目(三)

from rest_framework import viewsets
from rest_framework import mixins
from .models import UserFav
from .serializers import UserFavSerializer,UserFavDetailSerializer
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):
    ‘‘‘
    list：
        用户收藏列表
    create：
        收藏
    destroy:
        取消收藏
    ‘‘‘
    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‘

    # 动态选择serializer
    def get_serializer_class(self):
        if self.action == "list":
            return UserFavDetailSerializer
        elif self.action == "create":
            return UserFavSerializer
        return UserFavSerializer

    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)

from rest_framework import viewsets
from rest_framework.permissions import IsAuthenticated
from utils.permissions import IsOwnerOrReadOnly
from rest_framework_jwt.authentication import JSONWebTokenAuthentication
from rest_framework.authentication import SessionAuthentication
from .serializers import ShopCartSerializer, ShopCartDetailSerializer
from .models import ShoppingCart

class ShoppingCartViewset(viewsets.ModelViewSet):
    """
    购物车功能
    list:
        获取购物车详情
    create：
        加入购物车
    delete：
        删除购物记录
    """
    permission_classes = (IsAuthenticated, IsOwnerOrReadOnly)
    authentication_classes = (JSONWebTokenAuthentication, SessionAuthentication)

    serializer_class = ShopCartSerializer

    lookup_field = "goods_id"

    def get_queryset(self):
        return ShoppingCart.objects.filter(user=self.request.user)

    def get_serializer_class(self):
        if self.action == ‘list‘:
            return ShopCartDetailSerializer

from goods.serializers import GoodsSerializer
from .models import ShoppingCart, OrderGoods, OrderInfo
from rest_framework import serializers
from goods.models import Goods

import time

class ShopCartSerializer(serializers.Serializer):
    # 获取当前登录的用户
    user = serializers.HiddenField(
        default=serializers.CurrentUserDefault()
    )
    nums = serializers.IntegerField(required=True, label="数量", min_value=1,
                                    error_messages={
                                        "min_value": "商品数量不能小于一",
                                        "required": "请选择购买数量"
                                    })
    # 这里是继承Serializer，必须指定queryset对象，如果继承ModelSerializer则不需要指定
    # goods是一个外键，可以通过这方法获取goods object中所有的值
    goods = serializers.PrimaryKeyRelatedField(required=True, queryset=Goods.objects.all())

    # 继承的Serializer没有save功能，必须写一个create方法
    def create(self, validated_data):
        # validated_data是已经处理过的数据
        # 获取当前用户
        # view中:self.request.user；serizlizer中:self.context["request"].user
        user = self.context["request"].user
        nums = validated_data["nums"]
        goods = validated_data["goods"]

        existed = ShoppingCart.objects.filter(user=user, goods=goods)
        # 如果购物车中有记录，数量+1
        # 如果购物车车没有记录，就创建
        if existed:
            existed = existed[0]
            existed.nums += nums
            existed.save()
        else:
            # 添加到购物车
            existed = ShoppingCart.objects.create(**validated_data)

        return existed

    def update(self, instance, validated_data):
        # 修改商品数量
        instance.nums = validated_data["nums"]
        instance.save()
        return instance


class ShopCartDetailSerializer(serializers.ModelSerializer):
    ‘‘‘
    购物车商品详情信息
    ‘‘‘
    # 一个购物车对应一个商品
    goods = GoodsSerializer(many=False, read_only=True)
    class Meta:
        model = ShoppingCart
        fields = ("goods", "nums")