Mongoose:如何避免插入重复记录？

const mongoose = require('mongoose');

const schema = new mongoose.Schema({
  name: { type: String, unique: true },
  // 其他字段...
});

const Model = mongoose.model('Model', schema);

const Model = require('./model');

const newData = { name: 'example' };

Model.findOneAndUpdate(newData, newData, { upsert: true, new: true }, (err, doc) => {
  if (err) {
    console.error(err);
  } else {
    console.log('插入成功');
  }
});

const mongoose = require('mongoose');

const schema = new mongoose.Schema({
  name: { type: String },
  // 其他字段...
});

schema.pre('save', function (next) {
  const self = this;
  mongoose.models['Model'].findOne({ name: self.name }, (err, doc) => {
    if (doc) {
      next(new Error('记录已存在'));
    } else {
      next();
    }
  });
});

const Model = mongoose.model('Model', schema);