Mongoose sub-schema not generating _id

Question

I have two Schema objects:

contact.js:

/**
 * Contact Schema
 */
var ContactSchema = new Schema({
    name: String,
    role: String,
    phone: String,
    email: String,
    primary: Boolean
}, {timestamps: {createdAt: 'created', updatedAt: 'updated'}, _id: true, id: true});

client.js:

/**
 * Client Schema
 */
var ClientSchema = new Schema({
    name: {
        type: String,
        required: true,
        trim: true
    },
    comments: {
        type: String,
        trim: true
    },
    creator: {
        type: Schema.ObjectId,
        ref: 'User'
    },
    contacts: [ContactSchema],
    address: String,
}, {timestamps: {createdAt: 'created', updatedAt: 'updated'}});

Alas, when I save the Client object, no _id is assigned to the saved Contact .

But when I use this schema:

client.js:

/**
 * Client Schema
 */
var ClientSchema = new Schema({
    name: {
        type: String,
        required: true,
        trim: true
    },
    comments: {
        type: String,
        trim: true
    },
    creator: {
        type: Schema.ObjectId,
        ref: 'User'
    },
    contacts: [{
        name: String,
        role: String,
        phone: String,
        email: String,
        primary: Boolean
    }],
    address: String,
}, {timestamps: {createdAt: 'created', updatedAt: 'updated'}});

Contacts are saved with an auto-generated _id.

The way I save the clients is very straight forward:

var client = new Client(req.body);
client.creator = req.user;
client.save(function (err) {
    if (err) {
        console.log(err);
        return res.status(500).json({
            error: 'Cannot save the client'
        });
    }

    res.json(client);
});

And the contents of req.body is:

{ 
    name: 'A name for the client',
    contacts: [ { 
        name: 'A name for the contact',
        email: 'noy@test.com',
        role: 'UFO' 
    }] 
}

What am I missing?

Answer 1

So, I was completely off here. My problem was the way I was requiring the schema. I was using:

var ContactSchema = require('./contact');

to get the schema, but I didn't add module.exports = ContactSchema; at the end of the contact.js file.

Thanks to this question: MongoDB: How to use one schema as sub-document for different collections defined in different files I was able to solve mine (world's weirdest behavior though, since everything else was working).