.get（）需要回调函数，但在路由时得到[对象未定义]。（匿名函数）为get []

Hi every one I got this error in server.js there is no such error as I am beginner in this so I tried to read many answers on stackover flow but I didnt get answer. So can kindly some one edit this code or tell me what is problem please ?Hi every one I got this error in server.js ther