Files
ailine/app/nodes/tool_call.py

101 lines
3.8 KiB
Python

"""
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.config import get_stream_writer
# 本地模块
from app.graph.state import MessagesState
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
"""
from langchain_core.runnables.config import RunnableConfig
async def call_tools(state: MessagesState, config: RunnableConfig) -> Dict[str, Any]:
"""
工具执行节点(异步方法)
Args:
state: 当前对话状态
config: 运行时配置
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
# 获取流式写入器并发送工具调用开始事件
writer = get_stream_writer()
writer({"type": "custom", "data": {"type": "tool_start", "tool": tool_name}})
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))
# 发送工具调用完成事件
writer({"type": "custom", "data": {"type": "tool_end", "tool": tool_name, "success": True}})
except Exception as e:
debug(f" └─ ❌ 异常: {e}")
results.append(ToolMessage(content=f"Error: {e}", tool_call_id=tool_id))
# 发送工具调用失败事件
writer({"type": "custom", "data": {"type": "tool_end", "tool": tool_name, "success": False, "error": str(e)}})
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