How to separate the routes and models from app.js using NodeJS and Express

Question

I'm creating an app using Node and Express. However, I can see it'll soon become difficult to manage all the routes that are placed inside app.js. I have placed all my models in a subdirectory /models.

Here's my app current structure:

app.js models   -- products   -- customers   -- ... public views node_modules 

In app.js:

var express = require('express'),     routes = require('./routes'),     user = require('./routes/user'),     http = require('http'),     path = require('path'),     EmployeeProvider = require('./models/employeeprovider').EmployeeProvider,     Products = require('./models/products').Products,     Orders = require('./models/orders').Orders,     Customers = require('./models/customers').Customers,     checkAuth = function(req, res, next) {       if (!req.session.user_id) {         res.send('You are not authorized to view this page');       } else {         next();       }     };  var app = express(); 

Then some configuration like port, views directory, rendering engine, etc.

Further down app.js I've got the routes:

app.get('/product/edit', auth, function(req, res) {   Products.findAll(function(error, prds) {     res.render('product_edit', {       title: 'New Product',       products: prds     });   }); }); 

At the top I'm assigning the contents of models/products.js to a variable, all works fine. However keeping all routes inside app.js is not ideal. But if I move the routes to routes/product.js and load the Products models:

var prod = require('../models/products.js'); 

I get an error saying that object has no method findAll.

What am I doing wrong? How can I remove the routes from app.js?

Answer 1

As of express 4.x Router is added to support your case.

A router object is an isolated instance of middleware and routes. You can think of it as a “mini-application,” capable only of performing middleware and routing functions. Every Express application has a built-in app router.

Example from expressjs site:

// routes/calendarRouter.js  var express  = require('express'); var router = express.Router();  // invoked for any requested passed to this router router.use(function(req, res, next) {   // .. some logic here .. like any other middleware   next(); });  // will handle any request that ends in /events // depends on where the router is "use()'d" router.get('/events', function(req, res, next) {   // .. });  module.exports = router; 

Then in app.js:

// skipping part that sets up app  var calendarRouter = require('./routes/calendarRouter');  // only requests to /calendar/* will be sent to our "router" app.use('/calendar', calendarRouter);  // rest of logic