app.js

/**
 * Module dependencies.
 */

var express = require("express");
    
var app = module.exports = express.createServer();

// Configuration

app.configure(function() {
  app.use(express.bodyParser());
  app.use(express.methodOverride());
  app.use(app.router);
});

app.configure("development", function() {
  app.use(express.errorHandler({ dumpExceptions: true, showStack: true })); 
});

app.configure("production", function() {
  app.use(express.errorHandler());
});

// Routes

app.get("/", function(req, res) {
  res.send("index");
});

// How do I put the follow in a different file as if it were physically put here?

// app.get("/external", function(req, res) {
//   res.send("external");
// });
require("./external.js")(app);



// Only listen on $ node app.js

if (!module.parent) {
  app.listen(3000);
  console.log("Express server listening on port %d", app.address().port);
}

external.js

module.exports = function(app) {
  app.get("/external", function(req, res) {
    res.send("external");
  });
}