13.js

/**
 *Simple Express example for serving an API.
 */

var app = require('express')(),
	bodyParser = require('body-parser'),
	morgan = require('morgan'),
	port = process.env.PORT || 3000,
	MongoClient = require('mongodb').MongoClient,
	mongoUrl = 'mongodb://localhost:27017/expressdemo',
	_db;

app.use(morgan('dev'));

app.use(bodyParser.json());

MongoClient.connect(mongoUrl, function(err, db) {
	if (err) {
		console.error(err);
	} else {
		console.log('connected to mongo');
		_db = db;
		app.listen(port, function() {
			console.log('listening for requests on localhost:%s', port);
		});
	}
});

app.get('/users', function(req, res) {
	var collection = _db.collection('data');
	collection.find({}).toArray(function(err, result) {
		if (err) {
			console.error(err);
			res.status(500).end();
		} else {
			res.send({
				success: true,
				users: result
			});
		}
	});
});


app.get('/users/:name', function(req, res) {
	var name = req.params.name;
	var collection = _db.collection('data');

	collection.findOne({
		name: name
	}, function(err, user) {
		if (err) {
			console.error(err);
			res.status(500).end();
		} else {
			var result = user ? {
				success: true,
				user: user
			} : {
				success: false,
				reason: 'user not found: ' + name
			};
			res.send(result);
		}
	});
});


app.post('/users', function(req, res) {
	var user = req.body;
	var collection = _db.collection('data');

	// validate user, make sure doesn't already exist, etc.

	collection.insert(user, function(err, users) {
		if (err) {
			console.error(err);
			res.status(500).end();
		} else {
			res.send({
				success: true,
				user: user
			});
		}
	});
});