如何从子对象获取mongoose中的集合细节

const mongoose = require('mongoose');

const childSchema = new mongoose.Schema({
  details: String
});

const parentSchema = new mongoose.Schema({
  children: [childSchema]
});

const Parent = mongoose.model('Parent', parentSchema);

Parent.findOne({}).populate('children').exec((err, parent) => {
  if (err) {
    console.error(err);
    return;
  }

  // 获取第一个子对象的细节
  const firstChildDetails = parent.children[0].details;
  console.log(firstChildDetails);
});