mongoose - possible circular dependency? - node.js

Question

I have the following mongoose models in my express app:
//dog.js
var mongoose = require("mongoose");
var dogSchema = (exports.dogSchema = mongoose.Schema({
name: { type: String, required: true },
}));
Then I import dog.js to my user.js
//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],
});
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);
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?

Answer 1

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);
Then you can then choose to load the sub document using populate
Story.find({ --your criteria-- })
.populate('_creator')
.exec(function (err, story) {../});
You can then store the 2 schemas in separate .js files and require them both