Saving a value into an array of objects in Express/Angular/Node - node.js

Question

I'm still getting the hang of Express/Angular and how they work together to post to the server. I'm using the MEAN stack in my sample application.
The Schema for the object I'm trying to post looks like this in Express.
First define the 'Version' Schema:
var VersionSchema = new Schema({
title: {
type: String,
default: '',
trim: true
},
content: {
type: String,
default: '',
trim: true
},
submitted: {
type: Date,
default: Date.now
},
user: {
type: Schema.ObjectId,
ref: 'User'
}
});
The Version Schema is used in my Draft Schema. When a user creates a draft, it becomes a Version item in the versions array. When the draft is updated, it creates a new array item so all versions of the draft are saved.
var DraftSchema = new Schema({
versions: [VersionSchema],
});
The Draft Schema is set up as an Angular Service and injected into my controller. The service is boilerplate code for creating a $resource though so shouldn't be necessary.
I have two controllers to create the Draft object and save to Mongo: one with Angular, one with Express.
Angular controller:
$scope.create = function() {
var version = {
title: this.title,
content: this.content
};
var draft = new Drafts({
versions: [version]
});
draft.$save(function(response) {
$location.path("drafts/" + response._id);
});
};
In the angular controller I'm passing the title and contents to be saved to the Draft. As I understand it, you should not use an Angular controller to pass user information to the server. So this is handled by Express in the controller below.
Express controller:
exports.create = function(req, res) {
var draft = new Draft(req.body);
draft.versions = [req.user]; // Here is where my problem is, trying to save user
draft.save(function(err) {
if (err) {
return res.send('users/signup', {
errors: err.errors,
draft: draft
});
} else {
res.jsonp(draft);
}
});
};
You can see in my comment above where my problem is. I've looked through docs, SO questions, etc for the correct way to set my User property to the Versions array item being created here.
Note that if I move the User from the Version Schema to the Draft Schema and use:
draft.user = req.user;
To save the user then it works just fine. But I want the user to be saved into the VersionSchema.
To address Erick's comment below, this is a JSON representation of what I want my Draft model to look like. Versions is an Array because I want a new array item to be created each time the draft is updated.
[{
_id: 4h55542j232555000441,
versions: [
{
title: “A really great title”,
body: “On that day the people….”,
user: 5234523452349589hh23523,
submitted: Date
}
]
}];

Answer 1

draft.versions = [req.user]
Does the following: replace the versions array containing a version object with a new array containing the user object. This is not what you want.
As I see it, draft.versions has the following content:
[
{
title: '...',
content: '...'
}
]
To add a user id you need to do the following steps:
get the version object from the versions array
assign a new property to the version object and give it a value of user._id
var version = draft.versions[0]
version['user'] = req.user._id