状态管理#

到目前为止,我们已经讨论了如何在多智能体应用中构建组件——包括智能体、团队和终止条件。在许多情况下,将这些组件的状态保存到磁盘并在之后重新加载会非常有用。这在Web应用中尤其重要,因为无状态的端点需要响应请求,并从持久化存储中加载应用状态。

本笔记本将探讨如何保存和加载智能体、团队以及终止条件的状态。

保存与加载智能体#

我们可以通过调用AssistantAgent上的save_state()方法来获取智能体的状态。

from autogen_agentchat.agents import AssistantAgent
from autogen_agentchat.conditions import MaxMessageTermination
from autogen_agentchat.messages import TextMessage
from autogen_agentchat.teams import RoundRobinGroupChat
from autogen_agentchat.ui import Console
from autogen_core import CancellationToken
from autogen_ext.models.openai import OpenAIChatCompletionClient

model_client = OpenAIChatCompletionClient(model="gpt-4o-2024-08-06")

assistant_agent = AssistantAgent(
    name="assistant_agent",
    system_message="You are a helpful assistant",
    model_client=model_client,
)

# 在脚本中运行时使用asyncio.run(...)。
response = await assistant_agent.on_messages(
    [TextMessage(content="Write a 3 line poem on lake tangayika", source="user")], CancellationToken()
)
print(response.chat_message)
await model_client.close()
In Tanganyika's embrace so wide and deep,  
Ancient waters cradle secrets they keep,  
Echoes of time where horizons sleep.  
agent_state = await assistant_agent.save_state()
print(agent_state)
{'type': 'AssistantAgentState', 'version': '1.0.0', 'llm_messages': [{'content': 'Write a 3 line poem on lake tangayika', 'source': 'user', 'type': 'UserMessage'}, {'content': "In Tanganyika's embrace so wide and deep,  \nAncient waters cradle secrets they keep,  \nEchoes of time where horizons sleep.  ", 'source': 'assistant_agent', 'type': 'AssistantMessage'}]}
model_client = OpenAIChatCompletionClient(model="gpt-4o-2024-08-06")

new_assistant_agent = AssistantAgent(
    name="assistant_agent",
    system_message="You are a helpful assistant",
    model_client=model_client,
)
await new_assistant_agent.load_state(agent_state)

# 在脚本中运行时使用asyncio.run(...)。
response = await new_assistant_agent.on_messages(
    [TextMessage(content="What was the last line of the previous poem you wrote", source="user")], CancellationToken()
)
print(response.chat_message)
await model_client.close()
The last line of the poem was: "Echoes of time where horizons sleep."

备注

对于AssistantAgent,其状态包含model_context。 如果您编写自定义智能体,建议重写save_state()load_state()方法来自定义行为。默认实现会保存和加载空状态。

保存与加载团队#

我们可以通过调用团队的save_state方法来获取团队状态,并通过调用团队的load_state方法重新加载。

当调用团队的save_state方法时,它会保存团队中所有智能体的状态。

我们将从创建一个简单的RoundRobinGroupChat团队开始,该团队包含单个智能体,并要求它写一首诗。

model_client = OpenAIChatCompletionClient(model="gpt-4o-2024-08-06")

# 定义一个团队。
assistant_agent = AssistantAgent(
    name="assistant_agent",
    system_message="You are a helpful assistant",
    model_client=model_client,
)
agent_team = RoundRobinGroupChat([assistant_agent], termination_condition=MaxMessageTermination(max_messages=2))

# 运行团队并将消息流式传输到控制台。
stream = agent_team.run_stream(task="Write a beautiful poem 3-line about lake tangayika")

# 在脚本中运行时使用 asyncio.run(...)。
await Console(stream)

# 保存智能体团队的状态。
team_state = await agent_team.save_state()
---------- user ----------
Write a beautiful poem 3-line about lake tangayika
---------- assistant_agent ----------
In Tanganyika's gleam, beneath the azure skies,  
Whispers of ancient waters, in tranquil guise,  
Nature's mirror, where dreams and serenity lie.
[Prompt tokens: 29, Completion tokens: 34]
---------- Summary ----------
Number of messages: 2
Finish reason: Maximum number of messages 2 reached, current message count: 2
Total prompt tokens: 29
Total completion tokens: 34
Duration: 0.71 seconds

如果我们重置团队(模拟团队的实例化),并提问你写的诗的最后一行是什么?,我们会发现团队无法完成此任务,因为没有对之前运行的引用。

await agent_team.reset()
stream = agent_team.run_stream(task="What was the last line of the poem you wrote?")
await Console(stream)
---------- user ----------
What was the last line of the poem you wrote?
---------- assistant_agent ----------
I'm sorry, but I am unable to recall or access previous interactions, including any specific poem I may have composed in our past conversations. If you like, I can write a new poem for you.
[Prompt tokens: 28, Completion tokens: 40]
---------- Summary ----------
Number of messages: 2
Finish reason: Maximum number of messages 2 reached, current message count: 2
Total prompt tokens: 28
Total completion tokens: 40
Duration: 0.70 seconds
TaskResult(messages=[TextMessage(source='user', models_usage=None, content='What was the last line of the poem you wrote?', type='TextMessage'), TextMessage(source='assistant_agent', models_usage=RequestUsage(prompt_tokens=28, completion_tokens=40), content="I'm sorry, but I am unable to recall or access previous interactions, including any specific poem I may have composed in our past conversations. If you like, I can write a new poem for you.", type='TextMessage')], stop_reason='Maximum number of messages 2 reached, current message count: 2')

接下来,我们加载团队的状态并询问相同的问题。可以看到团队能够准确返回它写的诗的最后一行。

print(team_state)

# 加载团队状态。
await agent_team.load_state(team_state)
stream = agent_team.run_stream(task="What was the last line of the poem you wrote?")
await Console(stream)
{'type': 'TeamState', 'version': '1.0.0', 'agent_states': {'group_chat_manager/a55364ad-86fd-46ab-9449-dcb5260b1e06': {'type': 'RoundRobinManagerState', 'version': '1.0.0', 'message_thread': [{'source': 'user', 'models_usage': None, 'content': 'Write a beautiful poem 3-line about lake tangayika', 'type': 'TextMessage'}, {'source': 'assistant_agent', 'models_usage': {'prompt_tokens': 29, 'completion_tokens': 34}, 'content': "In Tanganyika's gleam, beneath the azure skies,  \nWhispers of ancient waters, in tranquil guise,  \nNature's mirror, where dreams and serenity lie.", 'type': 'TextMessage'}], 'current_turn': 0, 'next_speaker_index': 0}, 'collect_output_messages/a55364ad-86fd-46ab-9449-dcb5260b1e06': {}, 'assistant_agent/a55364ad-86fd-46ab-9449-dcb5260b1e06': {'type': 'ChatAgentContainerState', 'version': '1.0.0', 'agent_state': {'type': 'AssistantAgentState', 'version': '1.0.0', 'llm_messages': [{'content': 'Write a beautiful poem 3-line about lake tangayika', 'source': 'user', 'type': 'UserMessage'}, {'content': "In Tanganyika's gleam, beneath the azure skies,  \nWhispers of ancient waters, in tranquil guise,  \nNature's mirror, where dreams and serenity lie.", 'source': 'assistant_agent', 'type': 'AssistantMessage'}]}, 'message_buffer': []}}, 'team_id': 'a55364ad-86fd-46ab-9449-dcb5260b1e06'}
---------- user ----------
What was the last line of the poem you wrote?
---------- assistant_agent ----------
The last line of the poem I wrote is:  
"Nature's mirror, where dreams and serenity lie."
[Prompt tokens: 86, Completion tokens: 22]
---------- Summary ----------
Number of messages: 2
Finish reason: Maximum number of messages 2 reached, current message count: 2
Total prompt tokens: 86
Total completion tokens: 22
Duration: 0.96 seconds
TaskResult(messages=[TextMessage(source='user', models_usage=None, content='What was the last line of the poem you wrote?', type='TextMessage'), TextMessage(source='assistant_agent', models_usage=RequestUsage(prompt_tokens=86, completion_tokens=22), content='The last line of the poem I wrote is:  \n"Nature\'s mirror, where dreams and serenity lie."', type='TextMessage')], stop_reason='Maximum number of messages 2 reached, current message count: 2')

持久化状态(文件或数据库)#

在许多情况下,我们可能希望将团队的状态持久化到磁盘(或数据库)中,并在之后重新加载。状态是一个可以序列化到文件或写入数据库的字典。

import json

# # 将状态保存到磁盘

with open("coding/team_state.json", "w") as f:
    json.dump(team_state, f)

# # 从磁盘加载状态
with open("coding/team_state.json", "r") as f:
    team_state = json.load(f)

new_agent_team = RoundRobinGroupChat([assistant_agent], termination_condition=MaxMessageTermination(max_messages=2))
await new_agent_team.load_state(team_state)
stream = new_agent_team.run_stream(task="What was the last line of the poem you wrote?")
await Console(stream)
await model_client.close()
---------- user ----------
What was the last line of the poem you wrote?
---------- assistant_agent ----------
The last line of the poem I wrote is:  
"Nature's mirror, where dreams and serenity lie."
[Prompt tokens: 86, Completion tokens: 22]
---------- Summary ----------
Number of messages: 2
Finish reason: Maximum number of messages 2 reached, current message count: 2
Total prompt tokens: 86
Total completion tokens: 22
Duration: 0.72 seconds
TaskResult(messages=[TextMessage(source='user', models_usage=None, content='What was the last line of the poem you wrote?', type='TextMessage'), TextMessage(source='assistant_agent', models_usage=RequestUsage(prompt_tokens=86, completion_tokens=22), content='The last line of the poem I wrote is:  \n"Nature\'s mirror, where dreams and serenity lie."', type='TextMessage')], stop_reason='Maximum number of messages 2 reached, current message count: 2')