var roomModel = require('../../../models/room').roomModel;

roomModel.findOne({ name: req.body.roomName })
    .then(
        (room) => {
            return new Promise(function(resolve, reject) {
                //if no room present, create one, if present, check password
                if (room) {

                    if (room.password === req.body.roomPassword) {
                        return resolve(room);
                    } else {
                        return reject({
                            code: 401,
                            message: 'Room password not correct'
                        });
                    }
                } else {
                    // create new room with given data
                    var newRoom = roomModel({});
                    newRoom.name = req.body.roomName;
                    newRoom.password = req.body.roomPassword;
                    //newRoom.users = [];
                    newRoom.users[0] = {
                        name: req.body.userName
                    };

                    newRoom.save()
                        .then((data) => {
                            console.log(data);
                            if (!data) {
                                return reject({
                                    code: 500,
                                    message: 'Error when saving room'
                                });
                            } else {
                                return resolve(newRoom);
                            }
                        });
                }
            });
        }
    )
    .then((room) => {
        room.findOne({ 'users.name': req.body.userName })
            .then((user) => {
                console.log(user);
            });
    })

'use strict';
var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var userSchema = require('./user').userSchema;

var room = new Schema({
    name: String,
    password: String,
    users: [userSchema]
});

module.exports.roomSchema = room;
module.exports.roomModel = mongoose.model('room', room);

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

var user = new Schema({
    name: String
});

module.exports.userSchema = user;
module.exports.userModel = mongoose.model('user', user);

TypeError: room.findOne is not a function

roomModel.findOne({ name: req.body.roomName }).exec().then(/* your stuff */)

roomModel.find({ name: req.body.roomName }).exec().then(/* your stuff */)