Need help saving a game to a user's favorited games - reactjs

Question

I'm receiving an error when trying to associate a saved game to the user that saves it. The error says "cannot read property push of undefined"
The user, and game can be read in the console. I think it may have something to do with the user model during the initial creation of the user, however I can't be sure. I did notice if I try to console.log(user.favGames) it will be returned undefined.
I've tried everything I can think of, I've re-written the controller roughly 10 times, to no avail.
user model
const mongoose = require('mongoose')
const bcrypt = require('bcrypt')
const SALT_ROUNDS = 6
const Schema = mongoose.Schema
const userSchema = new Schema(
{
username: { type: String, unique: true },
email: { type: String, unique: true, unique: true },
password: { type: String, required: true },
avatar: { type: String },
favGames: { type: Schema.Types.ObjectId, ref: 'Game', default: null },
comments: { type: Schema.Types.ObjectId, ref: 'Comment', default: null }
},
{
timestamps: true
}
)
userSchema.set('toJSON', {
transform: function(doc, ret) {
delete ret.password
return ret
}
})
userSchema.pre('save', function(next) {
const user = this
if (!user.isModified('password')) return next()
bcrypt.hash(user.password, SALT_ROUNDS, function(err, hash) {
if (err) return next()
user.password = hash
next()
})
})
userSchema.methods.comparePassword = function(tryPassword, cb) {
bcrypt.compare(tryPassword, this.password, cb)
}
module.exports = mongoose.model('User', userSchema)
game model
const mongoose = require('mongoose')
const Schema = mongoose.Schema
let gameSchema = new Schema({
name: { type: String, required: true },
boxArtUrl: { type: String, required: true },
twitchID: { type: String, required: true },
comments: { type: Schema.Types.ObjectId, ref: "Comment"}
})
module.exports = mongoose.model('Game', gameSchema)
game router
const express = require('express')
const router = express.Router()
const gamesCtrl = require('../../controllers/gameCtrl')
function isAuthed(req, res, next) {
if (req.user) return next()
return res.status(401).json({ msg: 'Unauthorized ' })
}
router.get('/')
router.post('/', isAuthed, gamesCtrl.addGame)
module.exports = router
game controller
const User = require('../models/user')
const Game = require('../models/Game')
function addGame(req, res) {
Game.create({
name: req.body.name,
twitchID: req.body.id,
boxArtUrl: req.body.box_art_url
})
.then(game => {
User.findById(req.user._id)
.then(user => {
console.log(game)
console.log(user.favGames)
// user.favGames.push(game)
// user.save()
})
.catch(err =>
console.log('error when updating user with new game', err)
)
})
.catch(err => console.log('error saving game', err))
}
module.exports = {
addGame
}
the error is flagged in my controller at user.favGames.push(game). Note that when a user creates a profile there are no games associated with their profile. I'm pretty sure I'm calling on the actual data instance of the model, not the model itself. Thanks in advance for your assistance.

Answer 1

Your favGames (and also comments) must be defined as array in user model like this.
const userSchema = new Schema(
{
username: { type: String, unique: true },
email: { type: String, unique: true, unique: true },
password: { type: String, required: true },
avatar: { type: String },
favGames: [{ type: Schema.Types.ObjectId, ref: 'Game', default: null }],
comments: [{ type: Schema.Types.ObjectId, ref: 'Comment', default: null }]
},
{
timestamps: true
}
)
Also user.save() returns a promise, so you need use then block, or await.
So the addGame function must be like this (I converted the code to async/await)
async function addGame(req, res) {
try {
let game = await Game.create({
name: req.body.name,
twitchID: req.body.id,
boxArtUrl: req.body.box_art_url
});
let user = await User.findById(req.user._id);
if (user) {
user.favGames.push(game);
await user.save();
res.status(200).send("game and user saved");
} else {
console.log("user not found");
res.status(404).send("user not found");
}
} catch (err) {
console.log("Err: ", err);
res.status(500).send("Something went wrong");
}
}

Answer 2

Looks like it's a matter of checking to see if it exists:
User.findById(req.user._id)
.then(user => {
if (!Array.isArray(user.favGames)) {
user.favGames = [];
}
user.favGames.push(game);
user.save();
})