Simple mongoose example not working - node.js

Question

I am trying to run a simple mongoose/node example which I found here on stackoverflow:
var mongoose = require('mongoose'),
db = mongoose.connect('mongodb://localhost/db'),
Schema = mongoose.Schema;
var sentinel = setTimeout(function(){
throw "failed to connect to MongoDB after one minute!";
}, 60*1000); // 60 seconds
mongoose.model('User', new Schema({
properties: {
name : { type: String, index: true }
}
}));
var User = db.model('User');
var u = new User();
u.name = 'Foo';
u.save();
User.find().all(function(arr) {
clearTimeout(sentinel); // cancel the timeout sentinel
console.log('Users found');
console.log(arr);
console.log('length='+arr.length);
});
process.stdin.resume();
If I get the code right there should be an output in the terminal at the end of the script, where the message "Users found" and all users from the collection should be printed. But I just get the timeout message. Why that?
I am running my server on an Amazon EC2 micro instance. Node, Mongodb and mongoose are installed and a Mongodb server is running (I can interact with it from the terminal via "mongo"). I have also created the directory /data/db.

Answer 1

I don't know about mongoose but u.save() might be asynchronous because it writes to the DB. Try
u.save(function (err){
if(err) console.log(err);
User.find().all(function(arr) {
clearTimeout(sentinel); // cancel the timeout sentinel
console.log('Users found');
console.log(arr);
console.log('length='+arr.length);
});
});
Edit: This works fine
var mongoose = require('mongoose');
var connection = mongoose.connect('mongodb://localhost/my_database');
var Schema = mongoose.Schema
var User = new Schema({
author : String
, type : String
});
var MyUserModel = mongoose.model('User', User); //create and access the model User
var u = new MyUserModel();
u.author = 'authorname';
u.save(function(err){
if (err) console.log(err);
});
MyUserModel.find({}, function (err,docs) {
console.log(docs);
});

Answer 2

I handled this problem by adding one additional step in each router where I use DB.
It's a little bit messy but it works and 100% no leaks.
Something like this:
// file: 'routes/api/v0/users.js'
router
var User = require('../../../models/user').User,
rest = require('../../../controllers/api/v0/rest')(User),
checkDB = require('../../../middleware/checkDB');
module.exports = function (app) {
app.get('/api/v0/users', checkDB, rest.get);
app.get('/api/v0/users/:id', checkDB, rest.getById);
app.post('/api/v0/users', checkDB, rest.post);
app.delete('/api/v0/users', checkDB, rest.deleteById);
app.put('/api/v0/users', checkDB, rest.putById);
};
// file: 'middleware/checkDB.js'
var HttpError = require('../error').HttpError,
mongoose = require('../lib/mongoose');
// method which checks is DB ready for work or not
module.exports = function(req, res, next) {
if (mongoose.connection.readyState !== 1) {
return next(new HttpError(500, "DataBase disconnected"));
}
next();
};
PS If you know solution better, please let me know.