连接mysql时出错（getConnection）

Question

我正在尝试使用来自express with node的promise-mysql模块连接到数据库，我的文件如下。从控制台，我可以毫无问题地连接到mysql，就像使用phpmyAdmin或Workbench

当我收到错误消息

  

TypeError：pool.getConnection不是函数

Keys.ts

export default {

    database : {
        host : 'localhost',
        user: 'root',
        password: '124563',
        database: 'ng_db'
    }
}

database.ts

import mysql from 'promise-mysql';
import keys from './keys';

const pool = mysql.createPool(keys.database);

pool.getConnection()
    .then(connection => {
      pool.releaseConnection(connection);
        console.log('DB is Connected');

    });

export default pool;

gameController.ts

import { Request,Response } from 'express';
import pool from '../database';

class GameController {

    public index (req: Request, res: Response) {
      pool.query('DESCRIBE game');
      res.json('game')

    } 

}
export const gameController = new GameController();
export default gameController;