Files
agent-craft/05_langchain_advanced/06_streaming.py
T
2025-10-30 18:52:51 +08:00

79 lines
2.4 KiB
Python

import os
from dotenv import load_dotenv
load_dotenv()
api_key = os.getenv("OPENAI_API_KEY")
from langchain_openai import ChatOpenAI
from langchain.agents import AgentExecutor, create_tool_calling_agent
from langchain_core.prompts import ChatPromptTemplate, MessagesPlaceholder
from langchain_core.tools import tool # 导入 @tool
from langchain_community.chat_message_histories import ChatMessageHistory
from langchain_core.runnables import RunnableWithMessageHistory
from langchain.callbacks.streaming_stdout import StreamingStdOutCallbackHandler
# 配置llm
llm = ChatOpenAI(
model="deepseek-chat",
api_key=api_key,
base_url="https://api.deepseek.com",
streaming=True,
callbacks=[StreamingStdOutCallbackHandler()]
)
# 配置prompt(新增俩占位符 一个为对话历史记录,一个为agent的思考过程)
prompt = ChatPromptTemplate.from_messages([
('system','你是小智,一个帮助他人的智能助手。当你无法解答当前问题时,会调用工具来解决问题。'),
MessagesPlaceholder(variable_name="history"),
('human','{input}'),
MessagesPlaceholder(variable_name="agent_scratchpad")
])
# 配置tool
@tool
def get_weather(location):
"""模拟获得天气信息"""
return f"{location}当前天气:23℃,晴,风力2级"
tools = [get_weather]
# 配置agent
agent = create_tool_calling_agent(llm=llm,prompt=prompt,tools=tools)
# 配置AgentExecutor
agent_executor = AgentExecutor(agent=agent,tools=tools) # 这里没加verbose=True,想打印日志看思考链的可以自行打印
# 记忆存储--包装agent_executor
store = {}
def get_session_history(session_id:str):
if session_id not in store:
store[session_id] = ChatMessageHistory()
return store[session_id]
agent_with_memory = RunnableWithMessageHistory(
runnable=agent_executor,
get_session_history=get_session_history,
input_messages_key="input",
history_messages_key="history"
)
# 打印测试
session_id = 'user123'
if __name__ == '__main__':
while 1:
user_input = input('\n你:')
if user_input == 'quit':
print('拜拜~')
break
# 用于标记"AI:"这个内容
# flush=True保证"AI:"立即输出,而不是等缓存区存满再输出
print("AI: ", end="", flush=True)
response = agent_with_memory.invoke(
{'input': user_input},
config={'configurable': {'session_id': session_id}}
)
print()