Javascript TypeError:架构路径“product.type”的值无效，获取的值为；“未定义”；

我正在处理一个电子商务应用程序，在运行服务器时遇到错误，请参阅附件以供参考。当我使用身份验证时，它对我来说很好，但是当我开始在NodeJS中使用populate时，我开始出现错误，我无法解决这个问题

找到下面的代码

models/product.js

const mongoose = require("mongoose");
const { ObjectId } = mongoose.Schema;

const productSchema = new mongoose.Schema(
  {
    name: {
      type: String,
      trim: true,
      required: true,
      maxlength: 32
    },
    description: {
      type: String,
      trim: true,
      required: true,
      maxlength: 2000
    },
    price: {
      type: Number,
      required: true,
      maxlength: 32,
      trim: true
    },
    category: {
      type: ObjectId,
      ref: "Category",
      required: true
    },
    stock: {
      type: Number
    },
    sold: {
      type: Number,
      default: 0
    },
    photo: {
      data: Buffer,
      contentType: String
    }
  },
  { timestamps: true }
);

module.exports = mongoose.model("Product", productSchema);

models/user.js

const mongoose = require('mongoose')
const crypto = require('crypto')
const uuidv1 = require('uuid/v1')

// User Schema design in DB with mongoose
const userSchema = new mongoose.Schema({
    name: {
        type: String,
        required: true,
        maxlength: 32,
        trim: true
    },
    lastname: {
        type: String,
        maxlength: 32,
        trim: true
    },
    email: {
        type: String,
        trim: true,
        required: true,
        unique: true,
    },
    userinfo: {
        type: String,
        trim: true
    },
    encry_password: {
        type: String,
        required: true,
    },
    salt: String,
    role: {
        type: Number,
        default: 0
    },
    purchases: {
        type: Array,
        default: []
    }
}, {timestamps: true})

// Virtual field creation
// Reffering the virtual method with password and it will be stored in encry_password in DB
userSchema.virtual('password')
    .set(function(password) {
        this._password = password                   // Convention of using private variable
        this.salt = uuidv1()                        // populating salt with uuid
        this.encry_password = this.securePassword(password)
    })
    .get(function() {
        return this._password
    })

// Crypto format for password storing in DB
userSchema.methods = {
    // For authentication of user
    authenticate: function(plainpassword) {
        return this.securePassword(plainpassword) === this.encry_password
    },
    // For securing password
    securePassword: function(plainpassword) {
        if (!plainpassword) return ""
        try {
            return crypto.createHmac('sha256', this.salt)
            .update(plainpassword)
            .digest('hex')
        } catch(err) {
            return ""
        }
    }
}

module.exports = mongoose.model('User', userSchema)

controller/user.js

const User = require('../models/user')
const Order = require('../models/order')

exports.getUserById = (req, res, next, id) => {
    User.findById(id).exec((err, user) => {
        if(err || !user) {
            return res.status(400).json({
                err: "NO USER WAS FOUND IN DB"
            })
        }
        // Storing user in req object and profile object
        req.profile = user
        next()
    })
}

exports.getUser = (req, res) => {
    req.profile.salt = undefined
    req.profile.encry_password = undefined
    req.profile.createdAt = undefined
    req.profile.updatedAt = undefined
    return res.json(req.profile)
}

exports.updateUser = (req, res) => {
    User.findByIdAndUpdate(
        {_id : req.profile._id},
        {$set : req.body},
        {new : true, useFindAndModify: false},
        (err, user) => {
            if(err) {
                return res.status(400).json({
                    err: 'YOU ARE NOT ALLOWED TO UPDATE'
                })
            }
            user.salt = undefined
            user.encry_password = undefined
            res.json(user)
        }
    )
}

exports.userPurchaseList = (req, res) => {
    Order.find({user: req.profile._id})
    .populate('user', '_id name')
    .exec((err, order) => {
        if(err) {
            return res.status(400).json({
                err: "No Order in this account"
            })
        }
        return res.json(order)
    })
}

exports.pushorderInPurchaseList = (req, res, next) => {
    // Created an empty array for purchase list and pushing the elements
    let purchases = []
    req.body.order.products.forEach(product => {
        purchases.push({
                _id: product._id,
                name: product.name,
                description: product.description,
                category: product.category,
                quantity: product.quantity,
                amount: req.body.order.amount,
                transaction_id: req.body.order.transaction_id,
            })
        })

    User.findOneAndUpdate(
        {_id: req.profile._id},
        // updating purchases with local purchases array
        {$push: {purchases: purchases}},
        {new : true},
        (err, purchases) => {
            if(err) {
                return res.status(400).json({
                    error: 'Unable to save purchase list'
                })
            }
            next()
        }
    )
    
}

---

您的文件名是

user.js

和

product.js

，但您正在导入

require（'../models/user'）

和

require（'../models/order'）

，我认为应该是

require（'../models/product'）