如何将已有的mongodb数据库集成到当前项目中？

// 引入Mongoose驱动程序
const mongoose = require('mongoose');

// 配置数据库连接
const dbConfig = {
  host: 'localhost',
  port: 27017,
  database: 'mydb',
  username: 'myuser',
  password: 'mypassword'
};

// 创建数据库连接
mongoose.connect(`mongodb://${dbConfig.host}:${dbConfig.port}/${dbConfig.database}`, {
  useNewUrlParser: true,
  auth: {
    user: dbConfig.username,
    password: dbConfig.password
  }
});

// 定义数据模型
const UserSchema = new mongoose.Schema({
  name: String,
  age: Number
});
const User = mongoose.model('User', UserSchema);

// 执行数据库操作
const user = new User({ name: 'John', age: 25 });
user.save()
  .then(() => {
    console.log('User saved successfully');
    // 其他数据库操作...
  })
  .catch(error => {
    console.error('Error saving user:', error);
  });

// 关闭数据库连接
mongoose.connection.close();