How to stream a react agent with stream mode event?

[cris-m]

I was playing around with the react agent try to stream the result. If I use stream_mode as event, I don't get the response back but if I use message I get the response back.

The following is my call_model function I use in the graph:

async def call_model(
    state: State, config: RunnableConfig
) -> Dict[str, List[AIMessage]]:
    configuration = Configuration.from_runnable_config(config)

    configurable = config.get('configurable', {})
    user_info = configurable.get('user_info', {})
    current_time = datetime.now(tz=timezone.utc)

    prompt = ChatPromptTemplate.from_messages(
        [
            ("system", configuration.system_prompt),
            ("placeholder", "{messages}")

        ]
    ).partial(
        date=current_time.isoformat(),
        time=current_time.strftime("%H:%M:%S")
    )

    model = load_chat_model(configuration.model).bind_tools(TOOLS)
    message_value = await prompt.ainvoke(
        {
            "messages": state.messages,
            "user_info": user_info,
        },
        config,
    )

    response = cast(AIMessage, await model.ainvoke(message_value, config))
    if state.is_last_step and response.tool_calls:
        return {
            "messages": [
                AIMessage(
                    id=response.id,
                    content="Sorry, I could not find an answer to your question in the specified number of steps.",
                )
            ]
        }

    return {"messages": [response]}

Now I stream the response of the graph like this:

  async def stream_events():
        async for chunk in chatbot.astream({"messages": [("user", message.content)]}, config, stream_mode="events", version="v2"):
            print(chunk)
            if (
                chunk.event == "events" and
                chunk.data["event"] == "on_chat_model_stream" and
                len(chunk.data["data"]["chunk"]["content"]) > 0 and
                'text' in chunk.data["data"]["chunk"]["content"][0]
            ):
                yield f"data: {chunk.data['data']['chunk']['content'][0]['text']}\n\n"
            yield "event: close\ndata: [DONE]\n\n"

am I missing some this?

[vbarda]

@cris-m there is actually no stream_mode="events" in langgraph -- you need to use chatbot.astream_events({"messages": [("user", message.content)]}, config, version="v2"). hope this helps!