DRF学习之首页商品类别显示的实现（二十二）

一、首页商品类别显示
1.增加首页商品类别广告的model

2.xadmin显示

3.注册到xadmin中

4.views的实现

class IndexCategoryViewset(mixins.ListModelMixin, viewsets.GenericViewSet):
    """
    首页商品分类数据
    """
    queryset = GoodsCategory.objects.filter(is_tab=True, name__in=["生鲜食品", "酒水饮料"])
    serializer_class = IndexCategorySerializer

在xadmin后台手动增加brannds的图片数据
serializer进行嵌套时不会自动返回域名，需要进行配置，在嵌套的Serializer中添加一个参数。

如下：

二、商品点击数，收藏数的修改
1.进行方法的重载retrieve的重载来实现点击数的修改

class GoodsListViewSet(CacheResponseMixin, mixins.ListModelMixin, mixins.RetrieveModelMixin, viewsets.GenericViewSet):
    """
    商品列表页, 分页， 搜索， 过滤， 排序
    """
    # throttle_classes = (UserRateThrottle, )
    queryset = Goods.objects.all()
    serializer_class = GoodsSerializer
    pagination_class = GoodsPagination
    # authentication_classes = (TokenAuthentication, )
    filter_backends = (DjangoFilterBackend, filters.SearchFilter, filters.OrderingFilter)
    filter_class = GoodsFilter
    search_fields = ('name', 'goods_brief', 'goods_desc')
    ordering_fields = ('sold_num', 'shop_price')

    def retrieve(self, request, *args, **kwargs):
        instance = self.get_object()
        instance.click_num += 1
        instance.save()
        serializer = self.get_serializer(instance)
        return Response(serializer.data)

2.进行方法的重写perform_create来实现，收藏数的修改（也可以使用信号量进行修改）

class UserFavViewset(mixins.CreateModelMixin, mixins.ListModelMixin, mixins.RetrieveModelMixin,
                     mixins.DestroyModelMixin, viewsets.GenericViewSet):
    """
    list:
        获取用户收藏列表
    retrieve:
        判断某个商品是否已经收藏
    create:
        收藏商品
    """
    permission_classes = (IsAuthenticated, IsOwnerOrReadOnly)#验证必须要登录
    authentication_classes = (JSONWebTokenAuthentication, SessionAuthentication)#token验证
    lookup_field = "goods_id"#根据goods_id来寻找

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

    def perform_create(self, serializer):
        instance = serializer.save()
        goods = instance.goods
        goods.fav_num += 1
        goods.save()


    def get_serializer_class(self):
        if self.action == "list":
            return UserFavDetailSerializer
        elif self.action == "create":
            return UserFavSerializer

        return UserFavSerializer

3.库存和销量的修改，主要是进行方法的重写

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 perform_create(self, serializer):
        shop_cart = serializer.save()
        goods = shop_cart.goods
        goods.goods_num -= shop_cart.nums
        goods.save()

    def perform_destroy(self, instance):
        goods = instance.goods
        goods.goods_num += instance.nums
        goods.save()
        instance.delete()

    def perform_update(self, serializer):
        existed_record = ShoppingCart.objects.get(id=serializer.instance.id)
        existed_nums = existed_record.nums
        saved_record = serializer.save()
        nums = saved_record.nums-existed_nums
        goods = saved_record.goods
        goods.goods_num -= nums
        goods.save()

    def get_serializer_class(self):
        if self.action == 'list':
            return ShopCartDetailSerializer
        else:
            return ShopCartSerializer

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

4.商品销量修改

class AliPayView(APIView):
    def get(self, request):
        # 与post类似

    def post(self, request):
        """
        处理支付宝notify_url异步通知
        :param request:
        :return:
        """
        processed_dict = {}
        for key, value in request.POST.items():
            processed_dict[key] = value

        print('request.POST的值：', processed_dict)
        sign = processed_dict.pop('sign', None)  # 直接就是字符串了

        server_ip = get_server_ip()
        alipay = AliPay(
            app_id=app_id,  # 自己支付宝沙箱 APP ID
            notify_url="http://{}:8000/alipay/return/".format(server_ip),
            app_private_key_path=app_private_key_path,  # 可以使用相对路径那个
            alipay_public_key_path=alipay_public_key_path,  # 支付宝的公钥，验证支付宝回传消息使用，不是你自己的公钥,
            debug=alipay_debug,  # 默认False,
            return_url="http://{}:8000/alipay/return/".format(server_ip)
        )

        verify_result = alipay.verify(processed_dict, sign)  # 验证签名，如果成功返回True
        if verify_result:
            order_sn = processed_dict.get('out_trade_no')  # 原支付请求的商户订单号
            trade_no = processed_dict.get('trade_no')  # 支付宝交易凭证号
            trade_status = processed_dict.get('trade_status')  # 交易目前所处的状态

            # 更新数据库订单状态
            """
            OrderInfo.objects.filter(order_sn=order_sn).update(
                trade_no=trade_no,  # 更改交易号
                pay_status=trade_status,  # 更改支付状态
                pay_time=timezone.now()  # 更改支付时间
            )
            """
            orderinfos = OrderInfo.objects.filter(order_sn=order_sn)
            for orderinfo in orderinfos:
                orderinfo.trade_no = trade_no,  # 更改交易号
                orderinfo.pay_status = trade_status,  # 更改支付状态
                orderinfo.pay_time = timezone.now()  # 更改支付时间
                # 更改商品的销量
                order_goods = orderinfo.order_goods.all()
                for item in order_goods:
                    # 获取订单中商品和商品数量，然后将商品的销量进行增加
                    goods = item.goods
                    goods.sold_num += item.goods_nums
                    goods.save()

                orderinfo.save()

            # 给支付宝返回一个消息，证明已收到异步通知
            # 当商户收到服务器异步通知并打印出 success 时，服务器异步通知参数 notify_id 才会失效。
            # 也就是说在支付宝发送同一条异步通知时（包含商户并未成功打印出 success 导致支付宝重发数次通知），服务器异步通知参数 notify_id 是不变的。
            return Response('success')