Express.js 和 mongoose：使用 bash（异步）设置默认值

Question

如何将默认值（如异步的bdhash）设置为我的猫鼬模式中的一个字段？ 现在我只看到里面的承诺。但为什么？似乎我以正确的方式使用 async/await 。我也尝试在一个钩子中做到这一点（'validate'）

const mongoose = require('mongoose');
mongoose.Promise = global.Promise;
bcrypt = require('bcrypt');

hashIt = async () => {
  let pwd = new Date();
  pwd = pwd.toUTCString() + Math.random();

  return await bcrypt.hash(pwd, Number(process.env.SALT_WORK_FACTOR));
};

const businessSchema = new mongoose.Schema(
  {
    name: {
      type: String,
      trim: true,
      unique: 'Please enter a unique business name',
      required: 'Please enter a business name'
    },
    salt: {
      type: String,
      trim: true,
      default: () => {
        return hashIt();
      },
      required: 'Please enter a business salt'
    },
    created: {
      type: Date,
      default: Date.now
    }
  },
  {
    toJSON: { virtuals: true },
    toObject: { virtuals: true }
  }
);

/* Also tried this way 
businessSchema.pre('validate', next => {
  if (this.salt) {
    return next();
  }

  this.salt = hashIt();
  next();
}); */

module.exports = mongoose.model('Business', businessSchema);

有可能吗？如何？最好的方法:)

Answer 1

见http://mongoosejs.com/docs/defaults.html

检查这个例子：

var schema = new Schema({
  title: String,
  genre: {type: String, default: 'Action'}
});

var Movie = db.model('Movie', schema);

var query = {};
var update = {title: 'The Terminator'};
var options = {
  // Create a document if one isn't found. Required
  // for `setDefaultsOnInsert`
  upsert: true,
  setDefaultsOnInsert: true
};

Movie.
  findOneAndUpdate(query, update, options, function (error, doc) {
    assert.ifError(error);
    assert.equal(doc.title, 'The Terminator');
    assert.equal(doc.genre, 'Action');
  });