fix: 修复部分场景下历史记录保存异常的问题。回退到使用 AsyncSaver的双线备份消息模式

server/routers/chat_router.py

@@ -166,7 +166,7 @@ async def chat_agent(
             existing_count = len(existing_messages)
 
             # 只保存新增的消息
-            new_messages = messages
+            new_messages = messages[existing_count :]
 
             for msg in new_messages:
                 msg_dict = msg.model_dump() if hasattr(msg, "model_dump") else {}

src/agents/chatbot/graph.py

@@ -26,10 +26,8 @@ class ChatbotAgent(BaseAgent):
     def __init__(self, **kwargs):
         super().__init__(**kwargs)
         self.graph = None
-        self.checkpointer = InMemorySaver()
+        self.checkpointer = None
         self.context_schema = Context
-        self.workdir = Path(sys_config.save_dir) / "agents" / self.module_name
-        self.workdir.mkdir(parents=True, exist_ok=True)
         self.agent_tools = None
 
     def get_tools(self):
@@ -103,21 +101,14 @@ class ChatbotAgent(BaseAgent):
         builder.add_edge("tools", "chatbot")
         builder.add_edge("chatbot", END)
 
+        self.checkpointer = await self._get_checkpointer()
         graph = builder.compile(checkpointer=self.checkpointer, name=self.name)
         self.graph = graph
         return graph
 
 
 def main():
-    agent = ChatbotAgent(Context)
+    pass
-
-    thread_id = str(uuid.uuid4())
-    config = {"configurable": {"thread_id": thread_id}}
-
-    from src.agents.utils import agent_cli
-
-    agent_cli(agent, config)
-
 
 if __name__ == "__main__":
     main()

src/agents/common/base.py

@@ -1,10 +1,14 @@
 from __future__ import annotations
 
+import os
+from pathlib import Path
 from abc import abstractmethod
 
 from langgraph.graph.state import CompiledStateGraph
 from langgraph.checkpoint.memory import InMemorySaver
+from langgraph.checkpoint.sqlite.aio import AsyncSqliteSaver, aiosqlite
 
+from src import config as sys_config
 from src.agents.common.context import BaseContext
 from src.utils import logger
 
@@ -19,8 +23,10 @@ class BaseAgent:
 
     def __init__(self, **kwargs):
         self.graph = None  # will be covered by get_graph
-        self.checkpointer = InMemorySaver()
+        self.checkpointer = None
         self.context_schema = BaseContext
+        self.workdir = Path(sys_config.save_dir) / "agents" / self.module_name
+        self.workdir.mkdir(parents=True, exist_ok=True)
 
     @property
     def module_name(self) -> str:
@@ -103,3 +109,26 @@ class BaseAgent:
         例如: graph = workflow.compile(checkpointer=sqlite_checkpointer)
         """
         pass
+
+    async def _get_checkpointer(self):
+        # 创建数据库连接并确保设置 checkpointer
+        checkpointer = None
+
+        try:
+            checkpointer = AsyncSqliteSaver(await self.get_async_conn())
+
+        except Exception as e:
+            logger.error(f"构建 Graph 设置 checkpointer 时出错: {e}, 尝试使用内存存储")
+            checkpointer = InMemorySaver()
+
+        return checkpointer
+
+
+    async def get_async_conn(self) -> aiosqlite.Connection:
+        """获取异步数据库连接"""
+        return await aiosqlite.connect(os.path.join(self.workdir, "aio_history.db"))
+
+    async def get_aio_memory(self) -> AsyncSqliteSaver:
+        """获取异步存储实例"""
+        return AsyncSqliteSaver(await self.get_async_conn())
+

src/agents/react/graph.py

@@ -35,7 +35,9 @@ class ReActAgent(BaseAgent):
             return self.graph
 
         available_tools = get_buildin_tools()
+        self.checkpointer = await self._get_checkpointer()
 
+         # 创建 ReActAgent
         graph = create_react_agent(model, tools=available_tools, prompt=prompt, checkpointer=self.checkpointer)
         self.graph = graph
         logger.info("ReActAgent 使用内存 checkpointer 构建成功")

src/storage/db/models.py

@@ -83,6 +83,12 @@ class Message(Base):
             "tool_calls": [tc.to_dict() for tc in self.tool_calls] if self.tool_calls else [],
         }
 
+    def to_simple_dict(self):
+        return {
+            "role": self.role,
+            "content": self.content,
+        }
+
 
 class ToolCall(Base):
     """ToolCall table - stores tool invocations"""