ChatKit

agent-framework-chatkit 将 OpenAI ChatKit 线程项转换为代理框架消息,并将流式处理代理更新转换回 ChatKit 事件。 当想要将 ChatKit 前端与 Agent Framework Python后端配合使用时使用。

集成提供:

  • ThreadItemConverter 用于转换 ChatKit 线程项和附件。
  • stream_agent_response() 用于将流式代理更新转换为 ChatKit 事件。
  • simple_to_agent_input() 用于默认消息转换路径。

先决条件

  • Python 3.10 或更高版本。
  • 后端 Web 框架,如 FastAPI。
  • Node.js ChatKit 前端。
  • 生产前端域的 ChatKit 域密钥。

安装软件包

pip install agent-framework-chatkit --pre

创建 ChatKit 服务器

子类 ChatKitServer,创建 Agent Framework 代理,并为线程项和附件配置转换器。

class WeatherChatKitServer(ChatKitServer[dict[str, Any]]):
    """ChatKit server implementation using Agent Framework.

    This server integrates Agent Framework agents with ChatKit's server protocol,
    providing weather information with interactive widgets and time queries through Azure OpenAI.
    """

    def __init__(self, data_store: SQLiteStore, attachment_store: FileBasedAttachmentStore):
        super().__init__(data_store, attachment_store)

        logger.info("Initializing WeatherChatKitServer")

        # Create Agent Framework agent with Azure OpenAI
        # For authentication, run `az login` command in terminal
        try:
            self.weather_agent = Agent(
                client=FoundryChatClient(credential=AzureCliCredential()),
                instructions=(
                    "You are a helpful weather assistant with image analysis capabilities. "
                    "You can provide weather information for any location, tell the current time, "
                    "and analyze images that users upload. Be friendly and informative in your responses.\n\n"
                    "If a user asks to see a list of cities or wants to choose from available cities, "
                    "use the show_city_selector tool to display an interactive city selector.\n\n"
                    "When users upload images, you will automatically receive them and can analyze their content. "
                    "Describe what you see in detail and be helpful in answering questions about the images."
                ),
                tools=[get_weather, get_time, show_city_selector],
            )
            logger.info("Weather agent initialized successfully with Azure OpenAI")
        except Exception as e:
            logger.error(f"Failed to initialize weather agent: {e}")
            raise

        # Create ThreadItemConverter with attachment data fetcher
        self.converter = ThreadItemConverter(
            attachment_data_fetcher=self._fetch_attachment_data,
        )

转换和流式处理响应

加载线程历史记录,将其转换为代理框架消息,在流式处理模式下运行代理,并生成 ChatKit 事件。

async def respond(
    self,
    thread: ThreadMetadata,
    input_user_message: UserMessageItem | None,
    context: dict[str, Any],
) -> AsyncIterator[ThreadStreamEvent]:
    """Handle incoming user messages and generate responses.

    This method converts ChatKit messages to Agent Framework format using ThreadItemConverter,
    runs the agent, converts the response back to ChatKit events using stream_agent_response,
    and creates interactive weather widgets when weather data is queried.
    """
    from agent_framework import FunctionResultContent

    if input_user_message is None:
        logger.debug("Received None user message, skipping")
        return

    logger.info(f"Processing message for thread: {thread.id}")

    try:
        # Track weather data and city selector flag for this request
        weather_data: WeatherData | None = None
        show_city_selector = False

        # Load full thread history from the store
        thread_items_page = await self.store.load_thread_items(
            thread_id=thread.id,
            after=None,
            limit=1000,
            order="asc",
            context=context,
        )
        thread_items = thread_items_page.data

        # Convert ALL thread items to Agent Framework ChatMessages using ThreadItemConverter
        # This ensures the agent has the full conversation context
        agent_messages = await self.converter.to_agent_input(thread_items)

        if not agent_messages:
            logger.warning("No messages after conversion")
            return

        logger.info(f"Running agent with {len(agent_messages)} message(s)")

        # Run the Agent Framework agent with streaming
        agent_stream = self.weather_agent.run(agent_messages, stream=True)

        # Create an intercepting stream that extracts function results while passing through updates
        async def intercept_stream() -> AsyncIterator[AgentResponseUpdate]:
            nonlocal weather_data, show_city_selector
            async for update in agent_stream:
                # Check for function results in the update
                if update.contents:
                    for content in update.contents:
                        if isinstance(content, FunctionResultContent):
                            result = content.result

                            # Check if it's a WeatherResponse (string subclass with weather_data attribute)
                            if isinstance(result, str) and hasattr(result, "weather_data"):
                                extracted_data = getattr(result, "weather_data", None)
                                if isinstance(extracted_data, WeatherData):
                                    weather_data = extracted_data
                                    logger.info(f"Weather data extracted: {weather_data.location}")
                            # Check if it's the city selector marker
                            elif isinstance(result, str) and result == "__SHOW_CITY_SELECTOR__":
                                show_city_selector = True
                                logger.info("City selector flag detected")
                yield update

        # Stream updates as ChatKit events with interception
        async for event in stream_agent_response(
            intercept_stream(),
            thread_id=thread.id,
        ):
            yield event

完整示例还演示了 SQLite 支持的线程、文件上传、附件存储、操作和交互式小组件。

Warning

ChatKit 前端从 OpenAI 的 CDN 加载,并向 OpenAI 域发出出站请求。 它目前不能自承载,不适合空气夹住的环境。

后续步骤