feat: 移除 Async的Checkpointer，并默认配置了 InMemorySaver

Author: xerrors

src/agents/chatbot/graph.py

@@ -1,11 +1,9 @@
-import os
 import uuid
 from pathlib import Path
 from typing import Any, cast
 
 from langchain_core.messages import AIMessage, ToolMessage
 from langgraph.checkpoint.memory import InMemorySaver
-from langgraph.checkpoint.sqlite.aio import AsyncSqliteSaver, aiosqlite
 from langgraph.graph import END, START, StateGraph
 from langgraph.prebuilt import ToolNode, tools_condition
 from langgraph.runtime import Runtime
@@ -28,6 +26,7 @@ class ChatbotAgent(BaseAgent):
     def __init__(self, **kwargs):
         super().__init__(**kwargs)
         self.graph = None
+        self.checkpointer = InMemorySaver()
         self.context_schema = Context
         self.workdir = Path(sys_config.save_dir) / "agents" / self.module_name
         self.workdir.mkdir(parents=True, exist_ok=True)
@@ -90,8 +89,8 @@ async def dynamic_tools_node(self, state: State, runtime: Runtime[Context]) -> d
 
     async def get_graph(self, **kwargs):
         """构建图"""
-        # if self.graph:
-        #     return self.graph
+        if self.graph:
+            return self.graph
 
         builder = StateGraph(State, context_schema=self.context_schema)
         builder.add_node("chatbot", self.llm_call)
@@ -104,27 +103,9 @@ async def get_graph(self, **kwargs):
         builder.add_edge("tools", "chatbot")
         builder.add_edge("chatbot", END)
 
-        # 创建数据库连接并确保设置 checkpointer
-        try:
-            sqlite_checkpointer = AsyncSqliteSaver(await self.get_async_conn())
-            graph = builder.compile(checkpointer=sqlite_checkpointer, name=self.name)
-            self.graph = graph
-            return graph
-        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")
-            # 即使出错也返回一个可用的图实例，只是无法保存历史
-            checkpointer = InMemorySaver()
-            graph = builder.compile(checkpointer=checkpointer, name=self.name)
-            self.graph = graph
-            return graph
-
-    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())
+        graph = builder.compile(checkpointer=self.checkpointer, name=self.name)
+        self.graph = graph
+        return graph
 
 
 def main():

src/agents/common/base.py

@@ -3,6 +3,7 @@
 from abc import abstractmethod
 
 from langgraph.graph.state import CompiledStateGraph
+from langgraph.checkpoint.memory import InMemorySaver
 
 from src.agents.common.context import BaseContext
 from src.utils import logger
@@ -18,6 +19,7 @@ class BaseAgent:
 
     def __init__(self, **kwargs):
         self.graph = None  # will be covered by get_graph
+        self.checkpointer = InMemorySaver()
         self.context_schema = BaseContext
 
     @property
@@ -52,7 +54,7 @@ async def stream_messages(self, messages: list[str], input_context=None, **kwarg
         graph = await self.get_graph()
         context = self.context_schema.from_file(module_name=self.module_name, input_context=input_context)
         logger.debug(f"stream_messages: {context}")
-        # TODO 的 Checkpointer 似乎还没有适配最新的 Context API
+        # TODO Checkpointer 似乎还没有适配最新的 1.0 Context API
         input_config = {"configurable": input_context, "recursion_limit": 100}
         async for msg, metadata in graph.astream(
             {"messages": messages}, stream_mode="messages", context=context, config=input_config

src/agents/react/graph.py

@@ -1,7 +1,6 @@
 from pathlib import Path
 
 from langchain_core.messages import AnyMessage, SystemMessage
-from langgraph.checkpoint.sqlite.aio import AsyncSqliteSaver, aiosqlite
 from langgraph.prebuilt import create_react_agent
 from langgraph.runtime import get_runtime
 
@@ -37,8 +36,7 @@ async def get_graph(self, **kwargs):
 
         available_tools = get_buildin_tools()
 
-        sqlite_checkpointer = AsyncSqliteSaver(await aiosqlite.connect(self.workdir / "react_history.db"))
-        graph = create_react_agent(model, tools=available_tools, checkpointer=sqlite_checkpointer, prompt=prompt)
+        graph = create_react_agent(model, tools=available_tools, prompt=prompt, checkpointer=self.checkpointer)
         self.graph = graph
-        logger.info("ReActAgent使用SQLite checkpointer构建成功")
+        logger.info("ReActAgent 使用内存 checkpointer 构建成功")
         return graph