How is req and res accessible accross modules in Express.js

Question

While using express.js for handling various routes I want to encapsulate all of my route code in a seperate module, but how can I access the req and res object across modules, See the code below The main file examples.js is written as follows

var app = require('express').createServer();
var login = require('./login.js');
app.get('/login', login.auth(app.req, app.res));
app.listen(80);

What I want is that the login handling code be written in a seperate module/file called login.js, the question then is how will the response object be accessible in login.js. I think the following code will not work as because the type of req and res is not resolved.

exports.auth = function(req, res) {
    res.send('Testing');
}

Hence when I start the server with node example.js I get the error

'Cannot call method send of undefined'

How is the Request and REsponse objects passed along modules

Answer 1

This should work:

app.get('/login', login.auth);

Your example was attempting to pass the return value of the login.auth function as get handler for the request. The above instead passes the login.auth function itself as the handler.

Answer 2

TJ Holowaychuk made some great examples for express on the github page, here's the one about route separation:

https://github.com/visionmedia/express/tree/master/examples/route-separation