Express: accessing app.set() settings in routes

Question

In Express, I'm led to believe that global app settings can be created by doing something similar to the following in my main app.js file:

var express = require('express'),
    ...
    login = require('./routes/login');

var app = express();

app.configure(function(){
  ...
  app.set('ssoHostname', 'login.hostname.com');
  ...
});
...
app.get('/login', login.login);
...

now in ./routes/login.js, I'd like to access app.settings.ssoHostname, but if I attempt to run anything similar to (as per: How to access variables set using app.set() in express js):

...
exports.login = function(req, res) {
  var currentURL = 'http://' + req.header('host') + req.url;
  if (!req.cookies.authCookie || !User.isValidKey(req.cookies.authCookie)) {
    res.redirect(app.settings.ssoHostname + '/Login?returnURL=' + encodeURIComponent(currentURL));
  }
};
...

it does not recognize app:

ReferenceError: app is not defined

My questions are:

1. Is the approach I took of using app.set() for global settings that will be re-used often the "proper" way to do it and if so...
2. How do I access these settings in routes?
3. If not using app.set() for global settings to be used often, how would I set and get custom settings in routes?

Answer 1

Use req.app.get('ssoHostname')

Answer 2

At the end of your app.js file:

module.exports = app;

And then in routes/login.js:

var app = require('../app');

Now you have access to the actual app object and won't get a ReferenceError.