猫鼬-可能的循环依赖关系? [英] mongoose - possible circular dependency?

问题描述

我的Express应用程序中有以下猫鼬模型:

I have the following mongoose models in my express app:

//user.js
var mongoose  = require('mongoose');
var dog       = require('./dog');

var userSchema = mongoose.Schema({
  user: { type: String, required: true },
  pass: { type: String, required: true },
  dogs: [dog.dogSchema],
});

//dog.js
var mongoose  = require('mongoose');

var dogSchema = exports.dogSchema = mongoose.Schema({
  name: { type: String, required: true },
});

现在，从我的路线中，我正在这样创建一个新用户:

Now, from my routes I am creating a new user like this:

  var user   = require('../models/user');
  var dog   = require('../models/dog');

  dog = new dog.Dog(dogData);
  user = new user.User(data); //this will of course contain also dogData
  user.save(next);

这是执行这种操作的正确方法吗?我觉得我可能会以某种方式生成循环依赖关系，无论如何我觉得它不正确.关于如何在另一个模型文件中创建架构的子文档的任何想法?

Is this the correct way to do this kind of operation? I have the feeling that I might be generating a circular dependency somehow, and anyway it does not look right to me. Any ideas on how to create sub-documents where the schema is from another model file?

推荐答案

您可以在两个方向上创建同时引用，而不会产生循环问题.使用ref创建从一个文档到另一个文档的引用.从文档中:

You can create simultaneous references in two directions without creating circular problems. Create a reference from one document to the other using ref. From the docs:

http://mongoosejs.com/docs/populate.html

var mongoose = require('mongoose')
  , Schema = mongoose.Schema

var personSchema = Schema({
  _id     : Number,
  name    : String,
  age     : Number,
  stories : [{ type: Schema.Types.ObjectId, ref: 'Story' }]
});

var storySchema = Schema({
  _creator : { type: Number, ref: 'Person' },
  title    : String,
  fans     : [{ type: Number, ref: 'Person' }]
});

var Story  = mongoose.model('Story', storySchema);
var Person = mongoose.model('Person', personSchema);

然后，您可以选择使用populate

Then you can then choose to load the sub document using populate

Story.find({ --your criteria-- })
    .populate('_creator')
    .exec(function (err, story) {../});

然后您可以将2个模式存储在单独的.js文件中，并require两者都存储

You can then store the 2 schemas in separate .js files and require them both

这篇关于猫鼬-可能的循环依赖关系?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！