NodeJS + MongoDB via Mongoose

Model.js

var mongoose = require('mongoose');
mongoose.connect('YOUR_MONGODB_PATH');

var Schema = mongoose.Schema;

var ArticleSchema = new Schema({
	id : String,
	title : String,
	body : String,
	date : Date
});

mongoose.model('Article', ArticleSchema);

var Article = mongoose.model('Article');

ArticleProvider = {
	lastId : 0,

	add : function(title, body, callback) {
		this.lastId++;
	
		var article = new Article();
		article.id = this.lastId;
		article.title = title;
		article.body = body;
		article.date = Date.now();

		article.save(function(error) {
			if(error) { throw error; }
			console.log("Article saved\n");
			callback();
		});
	},

	getArticle : function(articleId, callback) { 
		Article.findOne( { id : articleId } , function(error, article) {
			if(error) { throw error; }
			callback(article);
		});
	}
}

exports.ArticleProvider = ArticleProvider;

node-mongoose-example.js

var http = require('http'),
    ArticleProvider = require('./Model').ArticleProvider;

http.createServer(function(request, response) {
	ArticleProvider.add('Hello Node', 'NodeJS + MongoDB via	Mongoose', function() {
		ArticleProvider.getArticle(1, function(article) {
			response.writeHead(200, { 'Content-Type' : 'text/plain' });
			response.write(article.id + " : " + article.title + "\n");
			response.write(article.body + "\n");
			response.end();
		});
	});
}).listen(8000);

Your code no optimize!