可以在Mongoose中相互引用两个模式吗？

Question

我有两个模式,我希望能够从另一个模式访问它们.我正在尝试做这样的事情:

//email.js

var mongoose = require('mongoose')
    ,Schema = mongoose.Schema
    , FoodItemSchema = require('../models/fooditem.js')
    , UserSchema = require('../models/user.js').schema
    , User = require('../models/user.js').model

    console.log(require('../models/user.js'));

    var emailSchema = new Schema({
        From : String,
        Subject : FoodItemSchema,
        Body : String,
        Date: Date,
        FoodItems : [FoodItemSchema],
        Owner : { type : Schema.Types.ObjectId , ref: "User" }
    });

    module.exports = {
        model: mongoose.model('Email', emailSchema),
        schema : emailSchema 
    }

//user.js

var mongoose = require('mongoose')
    ,Schema = mongoose.Schema
    , Email = require('../models/email.js').model
    , EmailSchema = require('../models/email.js').schema


console.log(require('../models/email.js'));

var userSchema = new Schema({
    googleID : String,
    accessToken : String,
    email : String,
    openId: Number,
    phoneNumber: String,
    SentEmails : [EmailSchema]
    // Logs : [{type: Schema.ObjectId, ref: 'events'}]
});
module.exports =  {
    model :  mongoose.model('User', userSchema),
    schema : userSchema
}

第一个console.log()打印空字符串,第二个打印出预期的字符串.我觉得我试图在创建其他模式之前尝试获取变量.这有一个共同的解决方法吗？或者我应该避免在我的设计中出现双重依赖？

Answer 1

是的,您可以在Mongoose中创建交叉引用.但是没有办法在Node.js中创建循环依赖.但是,您不需要,因为不需要用户模式来创建引用:

var mongoose = require('mongoose')
  , Schema = mongoose.Schema
  , FoodItemSchema = require('../models/fooditem.js');

var emailSchema = new Schema({
    From: String,
    Subject: FoodItemSchema,
    Body: String,
    Date: Date,
    FoodItems: [FoodItemSchema],
    Owner: { type: Schema.Types.ObjectId , ref: 'User' }
});

module.exports = {
    model: mongoose.model('Email', emailSchema),
    schema: emailSchema 
}