采用向量数据库实现长期记忆

app/nodes/tool_call.py

@@ -0,0 +1,90 @@
+"""
+工具执行节点模块
+负责执行 AI 调用的工具函数
+"""
+
+import asyncio
+from typing import Any, Dict
+from langchain_core.messages import AIMessage, ToolMessage
+from langgraph.runtime import Runtime
+
+# 本地模块
+from app.state import MessagesState, GraphContext
+from app.utils.logging import log_state_change
+from app.logger import debug, info
+
+
+def create_tool_call_node(tools_by_name: Dict[str, Any]):
+    """
+    工厂函数：创建工具执行节点
+    
+    Args:
+        tools_by_name: 名称到工具函数的映射字典
+        
+    Returns:
+        异步节点函数
+    """
+    
+    async def call_tools(state: MessagesState, runtime: Runtime[GraphContext]) -> Dict[str, Any]:
+        """
+        工具执行节点（异步方法）
+        
+        Args:
+            state: 当前对话状态
+            runtime: LangGraph 运行时上下文
+            
+        Returns:
+            包含 ToolMessage 的状态更新
+        """
+        log_state_change("tool_node", state, "进入")
+        
+        last_message = state['messages'][-1]
+        if not isinstance(last_message, AIMessage) or not last_message.tool_calls:
+            log_state_change("tool_node", state, "离开（无工具调用）")
+            return {"messages": []}
+
+        results = []
+        loop = asyncio.get_event_loop()
+        
+        info(f"🛠️  [工具调用] 准备执行 {len(last_message.tool_calls)} 个工具")
+        
+        for tool_call in last_message.tool_calls:
+            tool_name = tool_call["name"]
+            tool_args = tool_call["args"]
+            tool_id = tool_call["id"]
+            tool_func = tools_by_name.get(tool_name)
+
+            debug(f"   ├─ 调用工具: {tool_name} 参数: {tool_args}")
+
+            if tool_func is None:
+                err_msg = f"Tool {tool_name} not found"
+                debug(f"   └─ ❌ {err_msg}")
+                results.append(ToolMessage(content=err_msg, tool_call_id=tool_id))
+                continue
+
+            try:
+                # 修复闭包问题：将变量作为默认参数传入 lambda
+                # 如果工具支持异步 (ainvoke)，优先使用异步调用
+                if hasattr(tool_func, 'ainvoke'):
+                    observation = await tool_func.ainvoke(tool_args)
+                else:
+                    observation = await loop.run_in_executor(
+                        None,
+                        lambda args=tool_args: tool_func.invoke(args)  # 默认参数捕获当前值
+                    )
+                
+                # 字符打印
+                result_preview = str(observation).replace("\n", " ")
+                debug(f"   └─ ✅ 结果: {result_preview}")
+                results.append(ToolMessage(content=str(observation), tool_call_id=tool_id))
+            except Exception as e:
+                debug(f"   └─ ❌ 异常: {e}")
+                results.append(ToolMessage(content=f"Error: {e}", tool_call_id=tool_id))
+
+        info(f"🛠️  [工具调用] 执行完成，返回 {len(results)} 条 ToolMessage")
+        
+        result = {"messages": results}
+        log_state_change("tool_node", {**state, **result}, "离开")
+        return result
+    
+    return call_tools