修复状态兼容性问题：让旧节点同时支持 dict 和 dataclass

backend/app/main_graph/nodes/finalize.py

@@ -13,12 +13,21 @@ from app.logger import info, error
 
 from langchain_core.runnables.config import RunnableConfig
 
-async def finalize_node(state: MessagesState, config: RunnableConfig) -> Dict[str, Any]:
+
+def _get_attr(state, attr_name, default=None):
+    """通用方法：兼容 dict 和 dataclass 两种状态格式"""
+    if isinstance(state, dict):
+        return state.get(attr_name, default)
+    else:
+        return getattr(state, attr_name, default)
+
+
+async def finalize_node(state, config: RunnableConfig) -> Dict[str, Any]:
     """
     完成事件节点 - 发送完成事件，包含token使用情况和耗时信息
     
     Args:
-        state: 当前对话状态
+        state: 当前对话状态（兼容 dict 和 dataclass）
         config: 运行时配置
     
     Returns:
@@ -33,8 +42,8 @@ async def finalize_node(state: MessagesState, config: RunnableConfig) -> Dict[st
             "type": "custom", 
             "data": {
                 "type": "done",
-                "token_usage": state.get("last_token_usage", {}),
+                "token_usage": _get_attr(state, "last_token_usage", {}),
-                "elapsed_time": state.get("last_elapsed_time", 0.0)
+                "elapsed_time": _get_attr(state, "last_elapsed_time", 0.0)
             }
         })
         info("🏁 [完成事件] 已发送完成事件，包含token使用情况和耗时信息")

backend/app/main_graph/nodes/memory_trigger.py

@@ -4,19 +4,30 @@ from app.main_graph.state import MessagesState
 from app.memory.mem0_client import Mem0Client
 from app.logger import info
 
+
+def _get_attr(state, attr_name, default=None):
+    """通用方法：兼容 dict 和 dataclass 两种状态格式"""
+    if isinstance(state, dict):
+        return state.get(attr_name, default)
+    else:
+        return getattr(state, attr_name, default)
+
+
 # 全局变量，在 GraphBuilder 中注入
 _mem0_client: Mem0Client = None
 
+
 def set_mem0_client(client: Mem0Client):
     global _mem0_client
     _mem0_client = client
 
-async def memory_trigger_node(state: MessagesState, config: RunnableConfig) -> Dict[str, Any]:
+
+async def memory_trigger_node(state, config: RunnableConfig) -> Dict[str, Any]:
     """检测用户消息中的记忆指令，若命中则主动调用 Mem0 存储"""
     if _mem0_client is None:
         return {}
 
-    messages = state.get("messages", [])
+    messages = _get_attr(state, "messages", [])
     if not messages:
         return {}
 

backend/app/main_graph/nodes/retrieve_memory.py

@@ -11,6 +11,15 @@ from app.memory.mem0_client import Mem0Client
 from app.utils.logging import log_state_change
 from app.logger import debug
 
+
+def _get_attr(state, attr_name, default=None):
+    """通用方法：兼容 dict 和 dataclass 两种状态格式"""
+    if isinstance(state, dict):
+        return state.get(attr_name, default)
+    else:
+        return getattr(state, attr_name, default)
+
+
 def create_retrieve_memory_node(mem0_client: Mem0Client):
     """
     工厂函数：创建记忆检索节点
@@ -24,12 +33,12 @@ def create_retrieve_memory_node(mem0_client: Mem0Client):
     
     from langchain_core.runnables.config import RunnableConfig
     
-    async def retrieve_memory(state: MessagesState, config: RunnableConfig) -> Dict[str, Any]:
+    async def retrieve_memory(state, config: RunnableConfig) -> Dict[str, Any]:
         """
         记忆检索节点 - 使用 Mem0
         
         Args:
-            state: 当前对话状态
+            state: 当前对话状态（兼容 dict 和 dataclass）
             config: 运行时配置
         
         Returns:
@@ -41,11 +50,15 @@ def create_retrieve_memory_node(mem0_client: Mem0Client):
         user_id = config.get("metadata", {}).get("user_id", "default_user")
         
         # 兼容 dict 和对象两种消息格式
-        last_msg = state["messages"][-1]
+        messages = _get_attr(state, "messages", [])
-        if isinstance(last_msg, dict):
+        last_msg = messages[-1] if messages else None
-            query = str(last_msg.get("content", ""))
+        if last_msg:
+            if isinstance(last_msg, dict):
+                query = str(last_msg.get("content", ""))
+            else:
+                query = str(last_msg.content)
         else:
-            query = str(last_msg.content)
+            query = ""
         memory_text_parts = []
 
         # 确保 Mem0 已初始化（懒加载）
@@ -70,7 +83,7 @@ def create_retrieve_memory_node(mem0_client: Mem0Client):
 
         memory_context = "\n\n".join(memory_text_parts) if memory_text_parts else "暂无用户信息"
         result = {"memory_context": memory_context}
-        log_state_change("retrieve_memory", {**state, **result}, "离开")
+        log_state_change("retrieve_memory", {**state, **result} if isinstance(state, dict) else state, "离开")
         return result
     
     return retrieve_memory

backend/app/main_graph/nodes/summarize.py

@@ -11,6 +11,15 @@ from app.memory.mem0_client import Mem0Client
 from app.utils.logging import log_state_change
 from app.logger import debug, info, error, warning
 
+
+def _get_attr(state, attr_name, default=None):
+    """通用方法：兼容 dict 和 dataclass 两种状态格式"""
+    if isinstance(state, dict):
+        return state.get(attr_name, default)
+    else:
+        return getattr(state, attr_name, default)
+
+
 def create_summarize_node(mem0_client: Mem0Client):
     """
     工厂函数：创建记忆存储节点
@@ -24,12 +33,12 @@ def create_summarize_node(mem0_client: Mem0Client):
     
     from langchain_core.runnables.config import RunnableConfig
     
-    async def summarize_conversation(state: MessagesState, config: RunnableConfig) -> Dict[str, Any]:
+    async def summarize_conversation(state, config: RunnableConfig) -> Dict[str, Any]:
         """
         记忆存储节点 - 使用 Mem0
         
         Args:
-            state: 当前对话状态
+            state: 当前对话状态（兼容 dict 和 dataclass）
             config: 运行时配置
         
         Returns:
@@ -37,7 +46,7 @@ def create_summarize_node(mem0_client: Mem0Client):
         """
         log_state_change("summarize", state, "进入")
 
-        messages = state["messages"]
+        messages = _get_attr(state, "messages", [])
         if len(messages) < 4:
             debug("📝 [记忆添加] 对话过短，跳过")
             return {"turns_since_last_summary": 0}

backend/app/utils/logging.py

@@ -7,18 +7,26 @@ from app.config import ENABLE_GRAPH_TRACE
 from app.logger import debug, info
 
 
-def log_state_change(node_name: str, state: dict, prefix: str = "进入"):
+def _get_attr(state, attr_name, default=None):
+    """通用方法：兼容 dict 和 dataclass 两种状态格式"""
+    if isinstance(state, dict):
+        return state.get(attr_name, default)
+    else:
+        return getattr(state, attr_name, default)
+
+
+def log_state_change(node_name: str, state, prefix: str = "进入"):
     """
     记录状态变化日志
     
     Args:
         node_name: 节点名称
-        state: 当前状态
+        state: 当前状态（兼容 dict 和 dataclass）
         prefix: 日志前缀（"进入" 或 "离开"）
     """
     from app.logger import info
     
-    messages = state.get("messages", [])
+    messages = _get_attr(state, "messages", [])
     msg_count = len(messages)
     last_msg = messages[-1] if messages else None
     last_info = ""