Mongoose - can't save a document's properties - node.js

Question

So I have users and teams. I would like teams to have an array of users and I add a user to the team using the addUser function. I push to the teams user array successfully and save the results but right after that function I go to print out the same team and there are no users in the array. I am not sure if this is a .save() problem or what.
Any help is appreciated, thank you.
...
var userSchema = new Schema({
name: { type: String, required: true, unique: true },
age: Number
});
var teamSchema = new Schema({
name: { type: String, required: true, unique: true },
user: [{ type: Schema.ObjectId, ref: 'User' }]
});
userSchema.statics.createUser = function(opts, cb) {...};
teamSchema.statics.createTeam = function(opts, cb) {...};
teamSchema.statics.addUser = function(opts, cb) {
Team.find({_id: opts.team}).exec( function (err, team) {
team[0].user.push(opts.user);
team[0].save(function(err, save) {
console.log("--------------------");
console.log(team[0]); //team contains the added user here
console.log("--------------------");
return cb(null);
});
});
};
var User = mongoose.model('User', userSchema);
var Team = mongoose.model('Team', teamSchema);
var async = require('async');
var user1;
var user2;
var team;
async.waterfall([
function(d){User.createUser({name :'test1'},function(err, user){
user1 = user;
d(err);
});
},
function(d){User.createUser({name :'test2',age :20},function(err, user){
user2 = user;
d(err);
});
},
function(d){Team.createTeam({name :'team'},function(err, obj){
team = obj;
d(err);
});
},
function(d){Team.addUser({user : user1._id,team : team._id}, function(err){
console.log(team);
d(err);
});
},
function(d){Team.addUser({user : user2._id,team : team._id}, function(err){
console.log(team);
d(err);
});
}
],function(err){
if(err){
console.log(err);
}
else{
User.count({},function(err,count){console.log("Number of users:", count);});
Team.count({},function(err,count){console.log("Number of teams:", count);});
console.log(team);
}
});
returns:
--------------------
{ _id: 5583ed760958ab941a58bae9,
name: 'team',
__v: 1,
user: [ 5583ed760958ab941a58bae7 ] } //user1 added
--------------------
{ __v: 0, name: 'team', _id: 5583ed760958ab941a58bae9, user: [] }
//after that function call the team has no users
--------------------
{ _id: 5583ed760958ab941a58bae9,
name: 'team',
__v: 2,
user: [ 5583ed760958ab941a58bae7, 5583ed760958ab941a58bae8 ] }
//user2 added and user1 still there
--------------------
{ __v: 0, name: 'team', _id: 5583ed760958ab941a58bae9, user: [] } //no users again
Number of users: 2
Number of teams: 1 //only 1 team exists

Answer 1

Perhaps try using an update and push which would also simplify your code?
findAndModify (mongodb command)
findOneAndUpdate (mongoose command)
Team.findOneAndUpdate({"_id" : opts.team} , {$addToSet : { "user" : opts.user}}, function (err, foundUpdatedTeam) {
return cb(err,foundUpdatedTeam);
}, {new : true});
// be sure to update your team variable to reflect what is also in the database.
something like this:
function(d){Team.addUser({user : user1._id,team : team._id}, function(err, updatedTeam)
{
team = updatedTeam;
console.log(team);
d(err);
});
Few Notes:
I would change the team schema from user to TeamUsers or something more descriptive..it's a little confusing now.
note the use of AddToSet, that ensures that if you already added the user you won't be adding him twice.
This code is shorter and cleaner, you don't need to find the object if you can use the dedicated function, if however you wish to add the user to multiple teams I'd use update which allows you to update multiple documents.