def post(self, request):
"""订单创建"""
user = request.user
# ① 获取参数并进行校验
req_data = json.loads(request.body)
address_id = req_data.get('address_id')
pay_method = req_data.get('pay_method')
if not all([address_id, pay_method]):
return JsonResponse({'code': 400,
'message': '缺少必传参数'})
# 地址是否存在
try:
address = Address.objects.get(id=address_id, user=user)
except Exception as e:
return JsonResponse({'code': 400,
'message': '地址信息有误'})
# 1：货到付款 2：支付宝
if pay_method not in (1, 2):
return JsonResponse({'code': 400,
'message': '支付方式有误'})
# ② 组织订单数据
# 生成订单id
order_id = timezone.now().strftime('%Y%m%d%H%M%S') + '%09d' % user.id
# total_count和total_amount
total_count = 0
total_amount = 0
# 订单状态
if pay_method == 1:
# 货到付款：待发货
status = 2
else:
# 支付宝：待支付
status = 1
# 运费(此处固定)
freight = Decimal(10.00)
with transaction.atomic():
# 设置数据库操作时，事务中的保存点
sid = transaction.savepoint()
# ③ 向 tb_order_info 数据表中添加一行记录
order = OrderInfo.objects.create(order_id=order_id,
user=user,
address=address,
total_count=total_count,
total_amount=total_amount,
freight=freight,
pay_method=pay_method,
status=status)
# ④ 遍历用户要购买的商品记录，循环向 tb_order_goods 表中添加记录
# 从 redis 中获取用户要购买的商品信息
cart_helper = CartHelper(request)
cart_dict = cart_helper.get_redis_selected_cart()
sku_ids = cart_dict.keys()
for sku_id in sku_ids:
for i in range(3):
sku = SKU.objects.get(id=sku_id)
count = cart_dict[sku_id]
# 记录原始库存和销量
origin_stock = sku.stock
origin_sales = sku.sales
# 打印下单提示信息
print('下单用户：%s 商品库存：%d 购买数量：%d 尝试第 %d 次' % (
user.username, sku.stock, count, i + 1))
# 判断库存是否充足
if count > sku.stock:
# 数据库操作时，撤销事务中指定保存点之后的操作
transaction.savepoint_rollback(sid)
return JsonResponse({'code': 400,
'message': '商品库存不足'})
# 进行休眠操作，让 CPU 调度其它进程或线程，模拟订单并发问题
# import time
# time.sleep(10)
# 更新商品库存和销量
new_stock = origin_stock - count
news_sales = origin_sales + count
# 注意：update 方法返回的是被更新的行数
# update tb_sku set stock=<new_stock>, sales=<news_sales>
# where id=<sku_id> and stock=<origin_stock>;
res = SKU.objects.filter(id=sku.id,
stock=origin_stock).update(stock=new_stock,
sales=news_sales)
if res == 0:
if i == 2:
# 尝试下单更新了 3 次，仍然失败，报下单失败错误
# 数据库操作时，撤销事务中指定保存点之后的操作
transaction.savepoint_rollback(sid)
return JsonResponse({'code': 400,
'message': '下单失败!'})
# 更新失败，重新进行尝试
continue
# 增加对应SPU商品的销量
sku.spu.sales += count
sku.spu.save()
# 保存订单商品信息
OrderGoods.objects.create(order=order,
sku=sku,
count=count,
price=sku.price, )
# 累加计算订单商品的总数量和总价格
total_count += count
total_amount += count * sku.price
# 更新成功，跳出循环
break
total_amount += freight
order.total_count = total_count
order.total_amount = total_amount
order.save()
# ⑤ 清除用户购物车中已购买的记录
cart_helper.clear_redis_selected_cart()
# ⑥ 返回响应
return JsonResponse({'code': 0,
'message': '下单成功',
'order_id': order_id})
def post(self, request):
req_data = json.loads(request.body)
address_id = req_data.get("address_id")
pay_method = req_data.get("pay_method")
if not all([address_id, pay_method]):
return JsonResponse({"code": 400,
"message": "缺少必传参数"})
try:
address = Address.objects.get(id=address_id)
except Exception as e:
return JsonResponse({"code": 400,
"message": "地址信息有误"})
if pay_method not in [1, 2]:
return JsonResponse({"code": 400,
"message": "支付方式有误"})
user = request.user
order_id = timezone.now().strftime("%Y%m%d%H%M%S") + "%09d" % user.id
total_count = 0
total_amount = 0
if pay_method == 1:
status = 2
else:
status = 1
freight = Decimal(10.00)
# 开启事务
with transaction.atomic():
# 设置数据库操作时, 事务中的保存点
sid = transaction.savepoint()
order = OrderInfo.objects.create(order_id=order_id,
user=user,
address=address,
total_count=total_count,
total_amount=total_amount,
freight=freight,
pay_method=pay_method,
status=status)
cart_helper = CartHelper(request)
cart_dict = cart_helper.get_redis_selected_cart()
sku_ids = cart_dict.keys()
for sku_id in sku_ids:
for i in range(3):
sku = SKU.objects.get(id=sku_id)
count = cart_dict[sku_id]
# 记录原始库存和销量
origin_stock = sku.stock
origin_sales = sku.sales
print('下单用户：%s 商品库存：%d 购买数量：%d 尝试第 %d 次' % (
user.username, sku.stock, count, i + 1))
if count > sku.stock:
# 数据库操作时，撤销事务中指定保存点之后的操作
transaction.savepoint_commit(sid)
return JsonResponse({"code": 400,
"message": "商品库存不足"})
import time
time.sleep(10)
# 更新商品库存和销量
new_stock = origin_stock - count
new_sales = origin_sales + count
# 注意：update 方法返回的是被更新的行数
# update tb_sku set stock=<new_stock>, sales=<news_sales>
# where id=<sku_id> and stock=<origin_stock>;
res = SKU.objects.filter(id=sku.id,
stock=origin_stock).update(stock=new_stock,
sales=new_sales)
if res == 0:
if i == 2:
# 尝试下单更新了 3 次，仍然失败，报下单失败错误
# 数据库操作时，撤销事务中指定保存点之后的操作
transaction.savepoint_commit(sid)
return JsonResponse({"code": 400,
"message": "下单失败!"})
continue
sku.spu.sales += count
sku.spu.save()
OrderGoods.objects.create(order=order,
sku=sku,
count=count,
price=sku.price)
total_count += count
total_amount += count * sku.price
break
total_amount += freight
order.total_count = total_count
order.total_amount = total_amount
order.save()
cart_helper.clear_redis_selected_cart()
return JsonResponse({"code": 0,
"message": "下单成功",
"order_id": order_id})