express.js custom router (middleware)

router.js

/**
 * @category Application
 * @package  Middleware
 * @author   Kanstantsin A Kamkou (kkamkou@gmail.com)
 */

// required
var fs = require('fs'),
  express = require('express'),
  path = require('path');

// defaults
var pathRouters = CONSTANTS.PATH_ROOT + '/config/routes',
  pathController = CONSTANTS.PATH_APP + '/modules',
  routerList = [], dejavu;

// exporting stuff
module.exports = function (req, res, next) {
  // @see: https://gist.github.com/4351835
  dejavu = req.app.get('dejavu');

  // loading the routes and caching if needed
  if (!dejavu || !dejavu.has('routerList')) {
    // reading ftom the fs
    routerList = fs.readdirSync(pathRouters);

    // caching
    if (dejavu) {
      dejavu.set('routerList', routerList);
    }
  }

  routerList.forEach(function (pathRoute) {
    // defaults
    var instance = express(),
      rules = require(pathRouters + '/' + pathRoute),
      mdlName = path.basename(pathRoute, '.json');

    // configuaration
    instance.set('moduleName', mdlName)
      .set('views', [pathController, mdlName, 'views'].join('/'));

    // building the navigation set
    Object.keys(rules).forEach(function (controller) {
      // loading module itself
      var module = require(
        [pathController, mdlName, 'controllers', controller].join('/')
      );

      // lets iterate the object to combine parts
      Object.keys(rules[controller]).forEach(function (method) {
        Object.keys(rules[controller][method]).forEach(function (mask) {
          instance[method](rules[controller][method][mask], module[mask]);
        });
      });

      // exporting it
      req.app.use(instance);
    });
  });

  // jumping up
  next();
};

Folder structure:

/app
  /modules
    /mymodule
      /controllers
        /index.js
      /views
        /mobile
        /desktop
        /tablet
        index.jade

Example of the route-file (/config/routes/moduleName.json):

{
  "ajax": {
    "get": {
      "subscribe": "/something/subscribe",
      "timer": "/something/timer"
    }
  },

  "index": {
    "get": {
      "pdf": "/something/pdf/:mail?",
      "list": "/something/:city/:name/:id/list"
    }
  }
}

Setup: as usual middleware, with require()