As a web development framework, Express has become a de facto standard, joining the likes of Rails and Django. It's simple, fast, powerful, and makes server development an unthinkable joy. But many Node developers fail to completely understand the abstraction that Express provides them with.
Your challenge is this: write a micro-framework that implements the core property of Express that is the middleware architecture. It does not have to provide all features that Express has to offer, simply the core middleware feature.
Take the following example server:
var middleware = require('./middleware');
var app = middleware.createServer();
app.use(function (req, res, next) {
res.write('a');
next();
});
app.use('/hello', function (req, res, next) {
res.write('b');
next();
});
app.use(function (req, res, next) {
res.write('c');
next();
});
app.use('/hello', function (req, res) {
res.end('hello');
});
app.use('/goodbye', function (req, res) {
res.end('goodbye');
});
app.use(function (req, res) {
res.end('end');
});
app.listen(3000, function () {
console.log('Server started at 3000');
});
Your micro-framework will implement at least 3 methods:
createServer()
use(handler)
listen(port, callback)
The above server will run as you would expect:
GET /hello
would returnabchello
GET /goodbye
would returnacgoodbye
GET /
would returnacend
Do you have what it takes?
$ npm install
$ npm test