如何在Mongoose和Nodejs中创建增减路由

const express = require('express');
const mongoose = require('mongoose');

mongoose.connect('mongodb://localhost/mydatabase', { useNewUrlParser: true, useUnifiedTopology: true })
  .then(() => {
    console.log('Connected to MongoDB');
  })
  .catch((error) => {
    console.error('Error connecting to MongoDB', error);
  });

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

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

const router = express.Router();
app.use('/users', router);

router.post('/', async (req, res) => {
  try {
    const user = new User(req.body);
    await user.save();
    res.status(201).json(user);
  } catch (error) {
    res.status(400).json({ error: error.message });
  }
});

app.listen(3000, () => {
  console.log('Server started on port 3000');
});