提高创建对话的稳定性

apps/expertproducts/views.py

@@ -169,67 +169,77 @@ class NegotiationViewSet(viewsets.ModelViewSet):
     serializer_class = NegotiationSerializer
 
     def create(self, request, *args, **kwargs):
-        """创建谈判并返回包含初始消息的响应"""
-        serializer = self.get_serializer(data=request.data)
-        serializer.is_valid(raise_exception=True)
+        """创建谈判（事务保护版）"""
+        try:
+            # 开启事务：所有数据库操作要么全部成功，要么全部回滚
+            with transaction.atomic():
+                # 1. 验证请求数据
+                serializer = self.get_serializer(data=request.data)
+                serializer.is_valid(raise_exception=True)  # 自动返回400错误
 
-        # Extract creator and product from validated data
-        creator = serializer.validated_data['creator']
-        product = serializer.validated_data['product']
+                creator = serializer.validated_data['creator']
+                product = serializer.validated_data['product']
 
-        # 检查该用户是否存在
-        if not CreatorProfile.objects.filter(id=creator.id).exists():
-            return Response({
-                "code": 404,
-                "message": "未找到指定的达人",
-                "data": None
-            })
+                # 2. 检查达人是否存在
+                if not CreatorProfile.objects.filter(id=creator.id).exists():
+                    return Response(
+                        {"code": 404, "message": "未找到指定的达人", "data": None},
+                        status=status.HTTP_404_NOT_FOUND
+                    )
 
-        # Check if the product exists
-        if not Product.objects.filter(id=product.id).exists():
-            return Response({
-                "code": 404,
-                "message": "未找到指定的商品",
-                "data": None
-            })
+                # 3. 检查商品是否存在
+                if not Product.objects.filter(id=product.id).exists():
+                    return Response(
+                        {"code": 404, "message": "未找到指定的商品", "data": None},
+                        status=status.HTTP_404_NOT_FOUND
+                    )
 
-        # Check if a negotiation already exists for the same creator and product
-        existing_negotiation = Negotiation.objects.filter(creator=creator, product=product).first()
-        if existing_negotiation:
-            return Response({
-                "code": 400,
-                "message": "谈判已存在",
-                "data": {
-                    "negotiation_id": existing_negotiation.id
-                }
-            })
+                # 4. 检查是否已存在相同谈判
+                if Negotiation.objects.filter(creator=creator, product=product).exists():
+                    return Response(
+                        {
+                            "code": 400,
+                            "message": "谈判已存在",
+                            "data": {}
+                        },
+                        status=status.HTTP_400_BAD_REQUEST
+                    )
 
-        # 1. 创建谈判记录
-        negotiation = serializer.save()
+                # 5. 创建谈判记录
+                negotiation = serializer.save()
 
-        # 2. 生成并保存初始消息
-        initial_message = self._generate_welcome_message(negotiation)
-        message = Message.objects.create(
-            negotiation=negotiation,
-            role='assistant',
-            content=initial_message,
-            stage=negotiation.status
-        )
+                # 6. 生成初始消息
+                initial_message = self._generate_welcome_message(negotiation)
+                message = Message.objects.create(
+                    negotiation=negotiation,
+                    role='assistant',
+                    content=initial_message,
+                    stage=negotiation.status
+                )
 
-        # 4. 构建响应数据
-        response_data = {
-            "code": 200,
-            "message": "谈判已创建",
-            "data": {
-                "id": message.id,
-                **serializer.data,
-                "content": initial_message,
-                "created_at": message.created_at
-            }
-        }
+                # 7. 返回成功响应
+                return Response(
+                    {
+                        "code": 200,
+                        "message": "谈判已创建",
+                        "data": {
+                            "id": message.id,
+                            **serializer.data,
+                            "content": initial_message,
+                            "created_at": message.created_at
+                        }
+                    },
+                    status=status.HTTP_201_CREATED,
+                    headers=self.get_success_headers(serializer.data)
+                )
 
-        headers = self.get_success_headers(serializer.data)
-        return Response(response_data, status=status.HTTP_201_CREATED, headers=headers)
+        except Exception as e:
+            # 记录异常细节（实际生产环境应接入监控系统）
+            # logger.error(f"谈判创建失败: {str(e)}", exc_info=True)
+            return Response(
+                {"code": 500, "message": "服务器内部错误", "data": None},
+                status=status.HTTP_500_INTERNAL_SERVER_ERROR
+            )
 
     @action(detail=True, methods=['post'])
     def chat(self, request, pk=None):