通过Mongoose在MongoDB数据库中使用无服务器功能进行findById，并将结果以React的形式呈现出来--无法工作

const mongoose = require('mongoose');

mongoose.connect('mongodb://<username>:<password>@<hostname>:<port>/<database>', { useNewUrlParser: true, useUnifiedTopology: true })
  .then(() => {
    console.log('Database connected successfully');
  })
  .catch((error) => {
    console.error('Database connection error:', error);
  });

const mongoose = require('mongoose');

const userSchema = new mongoose.Schema({
  name: String,
  age: Number,
  email: String
});

const User = mongoose.model('User', userSchema);

module.exports = User;

import React, { useState, useEffect } from 'react';
import axios from 'axios';

const UserComponent = () => {
  const [user, setUser] = useState({});

  useEffect(() => {
    axios.get('/api/users/<userId>')
      .then(response => {
        setUser(response.data);
      })
      .catch(error => {
        console.error('Error fetching user:', error);
      });
  }, []);

  return (
    <div>
      <h1>User Details</h1>
      <p>Name: {user.name}</p>
      <p>Age: {user.age}</p>
      <p>Email: {user.email}</p>
    </div>
  );
};

export default UserComponent;