rag-gateway/app/api/chat.py

import json
import uuid

from fastapi import WebSocket, WebSocketDisconnect, APIRouter, Depends
import asyncio
import websockets
from sqlalchemy.orm import Session
from app.api import get_current_user_websocket
from app.config.config import settings
from app.models.base_model import get_db
from app.models.user_model import UserModel
from app.service.ragflow import RagflowService
from app.service.token import get_bisheng_token, get_ragflow_token

router = APIRouter()

# 存储客户端 WebSocket 连接
client_websockets = {}


# 中间层WebSocket 服务器，接收客户端的连接
@router.websocket("/ws/{agent_id}/{chat_id}")
async def handle_client(websocket: WebSocket,
                        agent_id: str,
                        chat_id: str,
                        current_user: UserModel = Depends(get_current_user_websocket),
                        db: Session = Depends(get_db)):
    await websocket.accept()
    print(f"Client {agent_id} connected")

    if agent_id == "0":
        agent_id = settings.bisheng_agent_id
    elif agent_id == "1":
        agent_id = settings.ragflow_agent_id
        chat_id = settings.ragflow_chat_id

    if chat_id == "0":
        chat_id = uuid.uuid4().hex

    client_websockets[chat_id] = websocket
    if agent_id == settings.ragflow_agent_id:
        ragflow_service = RagflowService(settings.ragflow_base_url)
        token = get_ragflow_token(db, current_user.id)
        try:
            async def forward_to_ragflow():
                while True:
                    message = await websocket.receive_json()
                    print(f"Received from client {chat_id}: {message}")
                    async for rag_response in ragflow_service.chat(token, chat_id, message["chatHistory"]):
                        try:
                            print(f"Received from ragflow: {rag_response}")
                            json_str = rag_response[5:].strip()
                            json_data = json.loads(json_str)
                            data = json_data.get("data")
                            if data is True:  # 完成输出
                                result = {"message": "", "type": "close"}
                            elif data is None:  # 发生错误
                                answer = json_data.get("retmsg", json_data.get("retcode"))
                                result = {"message": "内部错误：" + answer, "type": "stream"}
                            else:  # 正常输出
                                answer = json_data.get("data", {}).get("answer", "")
                                result = {"message": answer, "type": "stream"}
                            await websocket.send_json(result)
                            print(f"Forwarded to client {chat_id}: {result}")
                        except Exception as e:
                            result = {"message": f"内部错误： {e}", "type": "close"}
                            await websocket.send_json(result)
                            print(f"Error process message of ragflow: {e}")
            # 启动任务处理客户端消息
            tasks = [
                asyncio.create_task(forward_to_ragflow())
            ]
            await asyncio.wait(tasks, return_when=asyncio.FIRST_COMPLETED)
        except WebSocketDisconnect:
            print(f"Client {chat_id} disconnected")
        finally:
            del client_websockets[chat_id]

    else:
        token = get_bisheng_token(db, current_user.id)
        service_uri = f"{settings.bisheng_websocket_url}/api/v1/assistant/chat/{agent_id}?t=&chat_id={chat_id}"
        headers = {'cookie': f"access_token_cookie={token};"}

        async with websockets.connect(service_uri, extra_headers=headers) as service_websocket:

            try:
                # 处理客户端发来的消息
                async def forward_to_service():
                    while True:
                        message = await websocket.receive_json()
                        print(f"Received from client, {chat_id}: {message}")
                        # 添加 'agent_id' 和 'chat_id' 字段
                        message['flow_id'] = agent_id
                        message['chat_id'] = chat_id
                        msg = message["message"]
                        del message["message"]
                        message['inputs'] = {
                            "data": {"chatId": chat_id, "id": agent_id, "type": "assistant"},
                            "input": msg
                        }
                        await service_websocket.send(json.dumps(message))
                        print(f"Forwarded to bisheng: {message}")

                # 监听毕昇发来的消息并转发给客户端
                async def forward_to_client():
                    while True:
                        message = await service_websocket.recv()
                        print(f"Received from bisheng: {message}")
                        data = json.loads(message)
                        if data["type"] == "close" or data["type"] == "stream" or data["type"] == "end_cover":
                            if data["type"] == "close":
                                t = "close"
                            else:
                                t = "stream"
                            result = {"message": data["message"], "type": t}
                            await websocket.send_json(result)
                            print(f"Forwarded to client, {chat_id}: {result}")

                # 启动两个任务，分别处理客户端和服务端的消息
                tasks = [
                    asyncio.create_task(forward_to_service()),
                    asyncio.create_task(forward_to_client())
                ]
                done, pending = await asyncio.wait(tasks, return_when=asyncio.FIRST_COMPLETED)

                # 取消未完成的任务
                for task in pending:
                    task.cancel()
                    try:
                        await task
                    except asyncio.CancelledError:
                        pass

            except WebSocketDisconnect:
                print(f"Client {chat_id} disconnected")
            finally:
                del client_websockets[chat_id]