node.js - 尽管路径已填充，但 Mongoose 填充（）返回未定义

Question

我有以下猫鼬模式：

// server/models/Order.js

const { connection, model, Schema } = require('mongoose');

const itemSchema = new Schema({
    product: { type: Schema.Types.ObjectId, ref: 'Product', required: true },
    quantity: { type: Number, required: true },
    purchasePrice: {
        type: Schema.Types.Decimal128, get: Number, required: true, validate: {
            validator: function (value) {
                return !this.populated('product') || +value === this.product.price;
            },
        }
    },
});

const schema = new Schema({
    // ...
    items: [itemSchema],
    // ...
});

module.exports = model('Order', schema);

我的服务器创建一个新订单，填充它，然后尝试保存它：

// server/routers/order.js

const Order = require('../models/Order');

const order = new Order({ ... });
await order.populate('items.product').execPopulate();
const { _id } = await order.save();

它调用验证函数。调试器显示this.product引用有效文档，但this.populated('product')返回undefined，因此+value === this.product.price不评估比较。

这是 Mongoose 中的一个错误，还是出于某种原因它应该如何表现？

标签： node.jsmongodbvalidationmongoosemongoose-populate

Answer 1

是的，我认为这是一个错误。我也发现了这个。

const trackSchema=new Schema({
  song:{
    type:Schema.Types.ObjectId,
    ref:"Attachments",
   index:true
  },
  played:{
   type:Number,
   default:0
  }
});
const playlistSchema=const plSchema=new Schema({
  name:String,
  tracks:[trackSchema]
});

填充前：

playlist.tracks.forEach((track)=>{
   console.log('track.song: ',track.song);
   //this prints ObjectId
});

填充后：

await playlist.populate('tracks.song').execPopulate();
playlist.tracks.forEach((track)=>{
   console.log('track.song: ',track.song);
   //this prints undefined
});

修改为：

await playlist.populate('tracks').execPopulate();
playlist.tracks.forEach((track)=>{
   console.log('track.song: ',track.song);
   //this prints undefined
});

仍然未定义‍♂️</p>