更新Mongoose中的对象数组

const mongoose = require('mongoose');

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

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

User.updateOne({ _id: userId }, { $push: { friends: { name: 'John', age: 25 } } })
  .then(() => {
    console.log('添加成功');
  })
  .catch((error) => {
    console.error('添加失败', error);
  });

User.updateOne({ _id: userId, 'friends.name': 'John' }, { $set: { 'friends.$.age': 30 } })
  .then(() => {
    console.log('更新成功');
  })
  .catch((error) => {
    console.error('更新失败', error);
  });

User.updateOne({ _id: userId }, { $pull: { friends: { name: 'John' } } })
  .then(() => {
    console.log('删除成功');
  })
  .catch((error) => {
    console.error('删除失败', error);
  });