AiDA_Python/app/service/fashion_agent/service.py

import json
import logging
import sys
from pathlib import Path
from langgraph.stream import ProtocolEvent, StreamChannel, StreamTransformer
from app.service.fashion_agent.main_agent import build_main_graph
from langgraph.prebuilt import ToolCallTransformer
from typing import AsyncGenerator, TypedDict
from langchain_core.messages import HumanMessage
from app.schemas.fashion_agent import FashionAgentRequest

logger = logging.getLogger()


class CustomTransformer(StreamTransformer):
    required_stream_modes = ("custom",)

    def __init__(self, scope: tuple[str, ...] = ()) -> None:
        super().__init__(scope)
        self.log = StreamChannel()

    def init(self) -> dict:
        return {"custom": self.log}

    def process(self, event: ProtocolEvent) -> bool:
        if event["method"] == "custom":
            self.log.push(event["params"]["data"])
        return True


class FashionAgentService:

    async def run_stream(self, request: FashionAgentRequest) -> AsyncGenerator[str, None]:
        """流式运行 agent - 使用 v3 projections"""

        config = {"configurable": {"user_id": request.user_id}}

        agent = build_main_graph(enable_thinking=request.enable_thinking)
        state = {
            "messages": [HumanMessage(content=request.message)],
            "call_print": request.call_print,
            "call_logo": request.call_logo,
            "call_sketch": request.call_sketch,
            "call_design": request.call_design,
            "call_trending": request.call_trending,
            "call_explor": request.call_explor,
            "print_need_prompt_generation": request.print_need_prompt_generation,
            "sketch_need_prompt_generation": request.sketch_need_prompt_generation,
            "design_request_data": request.design_request_data,
        }

        stream = await agent.astream_events(state, config=config, version="v3", transformers=[ToolCallTransformer, CustomTransformer])

        tool_names = {}
        filter_tool_name = ["design_tool"]
        async for event in stream:
            if event["method"] == "tools":
                data = event["params"]["data"]
                tool_call_id = data.get("tool_call_id")

                # 记录 tool_name
                if data.get("event") == "tool-started":
                    tool_names[tool_call_id] = data.get("tool_name")

                # 通过 ID 查找 tool_name
                elif data.get("event") == "tool-finished":
                    tool_name = tool_names.get(tool_call_id, "unknown")

                    if tool_name in filter_tool_name:
                        continue

                    data["tool_name"] = tool_name

                response_event = {"event_type": "tool", "data": data}
                yield f"data: {json.dumps(response_event, ensure_ascii=False)}\n\n"

            elif event["method"] == "custom":
                data = event["params"]["data"]
                response_event = {"event_type": "tool", "data": data}
                yield f"data: {json.dumps(response_event, ensure_ascii=False)}\n\n"

            elif event["method"] == "messages":
                data = event["params"]["data"][0]
                if not isinstance(data, dict):
                    continue
                if data.get("event") != "content-block-delta":
                    continue
                block = data.get("delta") or {}

                if block.get("type") == "text-delta":
                    response_event = {"event_type": "messages", "data": {"event": data["event"]} | block}
                    yield f"data: {json.dumps(response_event, ensure_ascii=False)}\n\n"
                elif block.get("type") == "reasoning-delta":
                    response_event = {"event_type": "messages", "data": {"event": data["event"]} | block}
                    yield f"data: {json.dumps(response_event, ensure_ascii=False)}\n\n"
                else:
                    pass
                    # print(f"----------------{event}")
        response_event = {"event_type": "done"}
        yield f"data: {response_event}"


if __name__ == "__main__":
    import asyncio

    async def test_stream():
        """测试流式调用"""

        with open("app/service/fashion_agent/graph_node/design_graph/design_request_data.json", encoding="utf-8") as f:
            request_data = json.load(f)

        service = FashionAgentService()

        print("=" * 50)
        print("测试流式输出")
        print("=" * 50)
        request = FashionAgentRequest(
            message="生成一张草莓图案",
            call_print=True,
            # print_need_prompt_generation=False,
            # call_sketch=True,
            # sketch_need_prompt_generation=False,
            # call_logo=True,
            # call_explor=True,
            # call_design=True,
            # design_request_data=request_data,
        )
        async for chunk in service.run_stream(request):
            print(chunk, end="")

    # 运行测试
    asyncio.run(test_stream())