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.agent_model import AgentModel, AgentType
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()


# 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)):
    tasks = []
    await websocket.accept()
    print(f"Client {agent_id} connected")

    agent = db.query(AgentModel).filter(AgentModel.id == agent_id).first()
    if not agent:
        ret = {"message": "Agent not found", "type": "close"}
        await websocket.send_json(ret)
        return
    agent_type = agent.agent_type
    if chat_id == "" or chat_id == "0":
        ret = {"message": "Chat ID not found", "type": "close"}
        await websocket.send_json(ret)
        return

    if agent_type == AgentType.RAGFLOW:
        ragflow_service = RagflowService(settings.fwr_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}")
                    chat_history = message.get('chatHistory', [])
                    message["role"] = "user"
                    if len(chat_history) == 0:
                        chat_history = await ragflow_service.get_session_history(token, chat_id)
                        if len(chat_history) == 0:
                            chat_history = await ragflow_service.set_session(token, agent_id,
                                                                             message, chat_id, True)
                            if len(chat_history) == 0:
                                result = {"message": "内部错误：创建会话失败", "type": "close"}
                                await websocket.send_json(result)
                                await websocket.close()
                                return
                        else:
                            chat_history.append({
                                "content": message["message"],
                                "doc_ids": message.get("doc_ids", []),
                                "role": "user"
                            })
                    async for rag_response in ragflow_service.chat(token, chat_id, chat_history):
                        try:
                            if rag_response[:5] == "data:":
                                # 如果是，则截取掉前5个字符，并去除首尾空白符
                                text = rag_response[5:].strip()
                            else:
                                # 否则，保持原样
                                text = rag_response
                            try:
                                json_data = json.loads(text)
                                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": "message"}
                                else:  # 正常输出
                                    answer = data.get("answer", "")
                                    reference = data.get("reference", "")
                                    result = {"message": answer, "type": "message", "reference": reference }
                                await websocket.send_json(result)
                            except json.JSONDecodeError:
                                print(f"Error decode ragflow response: {text}")
                                pass

                        except Exception as e2:
                            result = {"message": f"内部错误： {e2}", "type": "close"}
                            await websocket.send_json(result)
                            print(f"Error process message of ragflow: {e2}")
            # 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 as e1:
            print(f"Client {chat_id} disconnected: {e1}")
            await websocket.close()
        except Exception as e:
            print(f"Exception occurred: {e}")

        finally:
            print("Cleaning up resources of ragflow")
            # 取消所有任务
            for task in tasks:
                if not task.done():
                    task.cancel()
                    try:
                        await task
                    except asyncio.CancelledError:
                        pass

    elif agent_type == AgentType.BISHENG:
        token = get_bisheng_token(db, current_user.id)
        service_uri = f"{settings.sgb_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 as e:
                print(f"WebSocket connection closed with code {e.code}: {e.reason}")
                await websocket.close()
                await service_websocket.close()
            except Exception as e:
                print(f"Exception occurred: {e}")

            finally:
                print("Cleaning up resources of bisheng")
                # 取消所有任务
                for task in tasks:
                    if not task.done():
                        task.cancel()
                        try:
                            await task
                        except asyncio.CancelledError:
                            pass
    else:
        ret = {"message": "Agent not found", "type": "close"}
        await websocket.send_json(ret)