day99-redis入门&增删改查购物车&购物车数据结构

进入到redis解压目录
命令行运行redis-server.exe redis.windows.conf

# redis 连接池
POOL = redis.ConnectionPool(host='127.0.0.1',
                            port=6379,
                            decode_responses=True)

REDIS_CONN = redis.Redis(connection_pool=POOL)

class ShoppingCarView(APIView):
    authentication_classes = [authentication.MyAuthentication, ]

    @staticmethod
    def post(request):
        my_res = BaseResponse()
        # {"course_id": 1, "price_policy_id": 1}
        try:
            """1.判断课程是否合法"""
            course_id = request.data.get('course_id', '')
            course_obj = models.Course.objects.filter(id=course_id).first()
            if not course_obj:
                raise MyException(101, '课程非法或不存在！')

            """2.判断价格策略是否合法"""
            price_policy_id = request.data.get('price_policy_id', '')
            all_price_policy_query_set = course_obj.price_policy.all()
            if not all_price_policy_query_set.filter(id=price_policy_id).first():
                raise MyException(102, '价格策略不合法')

            """3.拿到课程信息"""
            course_info = {
                'title': course_obj.title,
                'course_img': str(course_obj.course_img),
                'category': course_obj.category.title,
                'course_type': course_obj.get_course_type_display(),
                'brief': course_obj.brief,
                'level': course_obj.get_level_display(),
            }

            """4.拿到所有的价格策略"""
            price_policy_dict = {}
            for price_policy_obj in all_price_policy_query_set.order_by('price'):
                price_policy_dict[price_policy_obj.id] = {
                    'valid_period': price_policy_obj.get_valid_period_display(),
                    'price': price_policy_obj.price
                }

            """5.组建购物车"""
            shopping_car_key = SHOPPING_CAR.format(request.user.pk, course_id)
            course_info['price_policy_dict'] = price_policy_dict
            course_info['default_price_policy_id'] = price_policy_id

            """6.将组建好的购物车写进 Redis"""
            course_info = json.dumps(course_info)
            REDIS_CONN.set(shopping_car_key, course_info)
            my_res.code = 100
            my_res.msg = '加入购物车成功！'

        except MyException as e:
            my_res.code = e.code
            my_res.msg = e.msg
        except Exception as e:
            my_res.code = -100
            my_res.msg = str(e)

        return Response(my_res.dict)

    @staticmethod
    def get(request):
        my_res = BaseResponse()
        try:
            user_id = request.user.pk
            shopping_car_key = SHOPPING_CAR.format(user_id, '*')
            """找到所有的keys"""
            all_shopping_car_keys = REDIS_CONN.scan_iter(shopping_car_key)
            if not all_shopping_car_keys:
                raise MyException(201, '购物车不存在')
            shopping_car = {}
            for key in all_shopping_car_keys:
                shopping_car[key] = json.loads(
                    REDIS_CONN.get(key)
                )
            my_res.code = 200
            my_res.msg = 'SUCCESS'
            my_res.data = shopping_car

        except MyException as e:
            my_res.code = e.code
            my_res.msg = e.msg

        except Exception as e:
            my_res.code = -200
            my_res.msg = str(e)

        return Response(my_res.dict)

    @staticmethod
    def put(request):
        my_res = BaseResponse()
        # {"course_id": 1, "price_policy_id": 1}
        try:
            """1.检查课程id是否存在于redis中"""
            course_id = request.data.get('course_id', '')
            shopping_car_key = SHOPPING_CAR.format(request.user.pk, course_id)
            if not REDIS_CONN.exists(shopping_car_key):
                raise MyException(301, '购物车不存在此课程')

            """2.判断价格策略是否合法"""
            price_policy_id = request.data.get('price_policy_id', '')
            price_policy_query_set = models.Course.objects.filter(id=course_id).first().price_policy.all()
            if not price_policy_query_set.filter(id=price_policy_id):
                raise MyException(402, '价格策略不合法')

            """3.从Redis里面找到该用户的购物车，修改后重新写进 Redis"""
            shopping_car = json.loads(REDIS_CONN.get(shopping_car_key))
            shopping_car['default_price_policy_id'] = price_policy_id
            REDIS_CONN.set(shopping_car_key, json.dumps(shopping_car, ensure_ascii=True))
            my_res.code = 400
            my_res.msg = 'SUCCESS'
            my_res.data = shopping_car

        except MyException as e:
            my_res.code = e.code
            my_res.msg = e.msg
        except Exception as e:
            my_res.code = -400
            my_res.msg = str(e)
        return Response(my_res.dict)

    @staticmethod
    def delete(request):
        # 版本优化批量删除
        my_res = BaseResponse()
        try:
            """获取课程id，判断是否在Redis中"""
            course_id = request.data.get('course_id', '')
            shopping_car_key = SHOPPING_CAR.format(request.user.pk, course_id)
            if not REDIS_CONN.exists(shopping_car_key):
                raise MyException(501, '购物车不存在此课程')
            REDIS_CONN.delete(shopping_car_key)
            my_res.code = 500
            my_res.msg = '删除成功！'
        except MyException as e:
            my_res.code = e.code
            my_res.msg = e.msg
        except Exception as e:
            my_res.code = -500
            my_res.code = str(e)
        return Response(my_res.dict)

shopping_car = {
        # 购物车数据结构
        "shopping_car_ {}_ {}": {
            "id": "XXX",
            "title": "XXX",
            "course_img": "XXX",
            "price_policy_dict": {
                "valid_period": "XXX",
                "price": "XXX"
            },
            "default_price_policy_id": "XXX"
        },
}