我遵循[相同的文档代码][1]使用websocket graphql创建订阅服务器，但它不适用于graphql-ws和ws，当我删除serverCleanup定义时，代码有效，并且它也适用于旧的订阅库“订阅-传输-ws” 我的index.js
const { ApolloServer } = require('apollo-server-express')
const { ApolloServerPluginDrainHttpServer } = require('apollo-server-core')
const express = require('express')
const http = require('http')
const { makeExecutableSchema } = require('@graphql-tools/schema')
const { upperDirectiveTransformer } = require('./directives/uppercase')
const { WebSocketServer } = require ('ws');
const { useServer } = require('graphql-ws/lib/use/ws');
const { typeDefs } = require('./typeDefs')
const { resolvers } = require('./resolvers')
const jwt = require('jsonwebtoken');
const JWT_SECRET = 'f1BtnWgD3VKY';
const users = [
{
"id":1,
"name":"Magdalena",
"email":"mgrewes0@chronoengine.com",
"gender":"male",
"mobile":"734-324-1043",
"cumulativeGPA":92.1,
"isGraduated":true, …