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express-subdomain handling any subdomain

I'm trying to use https://github.com/bmullan91/express-subdomain for subdomain routing in express. The following are the contents of my main.js and src/routes/site files.
const express = require('express');
const bodyParser = require('body-parser');
const subdomain = require('express-subdomain');
const siteRouter = require('./src/routes/site');
const app = express()
app.use(express.json() );
app.use(express.urlencoded());
app.use(express.static('public'));
app.use(subdomain('*.www', siteRouter));
app.get('/', function(req, res) {
res.send('Homepage');
});
const server = app.listen(80,'x3.loc', function () {
var host = server.address().address;
var port = server.address().port;
console.log('X3 listening at http://%s:%s', host, port);
});
const express = require('express');
let router = express.Router();
router.get('/', function(req, res) {
res.send('Welcome to site');
});
module.exports = router;
This way of doing app.use(subdomain('*.www', siteRouter)); has been suggested in https://github.com/bmullan91/express-subdomain/issues/33 but does not work.
I have also tried just * as the subdomain aswell, but that caused the homepage w/o a subdomain, to get treated like one aswell. How could I get this to work?

We know that / matches any base path regardless of subdomain. So I made your homepage middleware "subdomain-aware" like so:
app.get('/', function(req, res,next) {
/* If there are any subdomains, skip to next handler, since request is not for the main home page */
if (req.subdomains.length > 0) {
return next();
}
res.send('Homepage');
});
Then I placed the middleware for subdomains below the homepage middleware like so:
app.use(subdomain('*', siteRouter));
This makes homepage middleware to serve requests for x3.loc and the subdomain middleware to serve requests for any subdomain like api.x3.loc or api.v1.x3.loc.
But in my opinion, the real fix should be done in the module. I think it should be changed so that either the case where req.subdomains being empty is handled, or * is matched against an actual string, instead of skipping the iteration.
I am surprised that the fix suggested in bug 33 worked as-is for the reporter. In my testing, it works the opposite way i.e. www.example.com goes to subdomain middleware while stat1.example.com goes to the homepage middleware. Perhaps the reporter saw this and swapped the middleware bodies.

Setting correct structure for a node app

Introduction
So far I have three files, one test.js is a file where I have built three functions that work.
But now I am trying to structure using MVC or at least some pattern. So now I router.js and app.js
Question
Should I put my promise functions from test.js in my config.js or server.js or something else, Im just interested in how people would do this and whats the correct way of structuring NodeJS.
server.js
In here start the server and apply the routes to my app
var configure = require('./router');
var express = require('express');
var app = express();
var port = process.env.PORT || 8080;
// get an instance of router
var router = express.Router();
configure(router);
app.listen(port);
console.log('Server has started!! ' + port);
// apply the routes to our application
app.use('/', router);
config.js
In here I build my routes
module.exports = function (router) {
// route middleware that will happen on every request
router.use(function (req, res, next) {
// log each request to the console
console.log(req.method, req.url);
// continue doing what we were doing and go to the route
next();
});
// home page route (http://localhost:8080)
router.get('/', function (req, res) {
res.send('im the home page!');
});
// sample route with a route the way we're used to seeing it
router.get('/sample', function (req, res) {
res.send('this is a sample!');
});
// about page route (http://localhost:8080/about)
router.get('/about', function (req, res) {
res.send('im the about page!');
});
// route middleware to validate :name
router.param('name', function (req, res, next, name) {
// do validation on name here
console.log('doing name validations on ' + name);
// once validation is done save the new item in the req
req.name = name;
// go to the next thing
next();
});
// route with parameters (http://localhost:8080/hello/:name)
router.get('/hello/:name', function (req, res) {
res.send('hello ' + req.params.name + '!');
})
// app.route('/login')
// show the form (GET http://localhost:8080/login)
.get('/login', function (req, res) {
res.send('this is the login form');
})
// process the form (POST http://localhost:8080/login)
.post('/login', function (req, res) {
console.log('processing'); // shows on console when post is made
res.send('processing the login form!'); // output on postman
});
};
test.js
In here is a list of functions that are a chain of promises getting data and API Keys
(small function, one of many that feed into each over)
var firstFunction = function () {
return new Promise (function (resolve) {
setTimeout(function () {
app.post('/back-end/test', function (req, res) {
console.log(req.body);
var login = req.body.LoginEmail;
res.send(login);
resolve({
data_login_email: login
});
});
console.error("First done");
}, 2000);
});
};

My recommended structure is to put everything except server.js in lib directory so all your app is lib/ plus server.js - everything else is package.json, dependencies in node_modules (created on npm install, not in the repo), .gitignore, config files for Travis, Circle, Heroku or whatever service you're using, some README.md and things like that.
Now, server.js is just bare minimum that requires lib/app:
const app = require('./lib/app');
and starts the server with something like:
const server = app.listen(app.get('port'), () => {
logger.info('%s listening on port %s', app.get('name'), app.get('port'));
});
server.on('error', (err) => {
logger.error(err.message || err);
process.exit(1);
});
where logger is some higher lever logger like Winston or something like that.
That's it. Now, lib/app.js is minimum code that loads the middleware like body parsers etc., creates the express app and sets the variables for port and name and then uses a router that is exported by lib/routes:
const routes = require('./routes');
// ...
app.use('/', routes);
The lib/app should be enough to use for testing with tools like supertest but it doesn't listen on any port - server.js does. This is important to simplify testing.
The router exported by lib/routes is used for everything and you can start with a single lib/routes.js file and then convert it to lib/routes/index.js plus several files in lib/routes as needed.
The routes only define the actual routes and input validation with a module like e.g. express-validation and register controllers that are exported by lib/controllers - that can start as lib/controllers.js and get converted to lib/controllers/index.js plus lib/controllers/*.js as needed - just like the routes.
Then I would add top level spec or test or tests directory where all of the tests go. The tests can require your lib/app to run the tests on it with no need to listen on actual TCP ports - those will test your routes with actual controllers. Other tests will require lib/util and run some unit tests on your utilities etc. Make sure to use a tool like istanbul or nyc to calculate the test coverage.
The database schemas and data models would go to lib/schemas and lib/models, some utility helpers in lib/util, some config loading code in lib/config etc.
This is quite flexible layout and works pretty well. You can start with just few files:
README.md
LICENSE.md
package.json
server.js
lib/app.js
lib/routes.js
lib/controllers.js
lib/config.js
etc. and easily convert all of the xxx.js file into xxx/index.js with entire folder of smaller xxx/*.js files as needed.
The main difference from your approach is that I recommend exporting routers and using them by higher level routers instead of passing the high level router into lower lever modules that export functions that take routers to work on.
So instead of:
const moreSpecific = require('more-specific');
const moreGeneral = express.Router();
moreSpecific(moreGeneral);
and then in more specific:
module exports = (router) => {
router.use('/abc/xyz', ...);
};
I would recommend exporting a more specific router in a file e.g. routes/abc.js:
const router = express.Router();
router.use('/xyz', ...);
module exports = router;
and then in more general router e.g. in routes/index.js:
const abc = require('abc');
const router = express.Router();
router.use('/abc', abc);
// and export the main router for other modules like app.js to use:
module.exports = router;
to have a route like /abc/xyz.

Why am I getting "name undefined" when trying to post using Express and Body Parser

I'm attempting to build a MEAN app and trying to test POSTing with POSTMAN. When I do, I keep getting the dreaded "TypeError: Cannot read property 'name' of undefined". If I type in a simple string, the POST goes through fine. But when I use "req.body.name" I get the error. I've looked in every place and I'm not seeing my mistake. I even followed the suggestions on this thread with no luck. Any help or suggestions would be greatly appreciated.
Here's the code I am currently working with in my server.js file:
const express = require('express');
var bodyParser = require('body-parser');
var Bear = require('./models/bear')
var path = require('path');
var mongoose = require('mongoose');
var router = express.Router();
var app = express();
var staticAssets = __dirname + '/public';
app.use(express.static(staticAssets));
app.use('/api', router)
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({extended: true}));
// Routes for my API
//===================================
// middleware to use for all requests
router.use(function(req,res,next){
// logging happens here
console.log('Something will happen.');
next(); // Head to the next router...don't stop here
});
// Test router to make sure everything is working (accessed at GET http://localhost:3000/api)
router.get('/', function(req, res){
res.json({message: 'hooray! welcome to our api!'})
})
//More routes will happen here with routes that end in "/bears"
router.route('/bears')
//Create a bear (accessed at POST http://localhost:3000/api/bears)
.post(function(req,res){
var bear = new Bear(); // Create a new instance of the bear model
console.log(req);
bear.name = req.body.name; // set the bears name (comes from the request)
//res.send(200, req.body);
bear.save(function(err){
if (err)
res.send(err);
res.json({message: 'Bear Created!!'});
});
});
//======================================
//var Products = require('./products.model.js');
var Product = require('./models/product.model');
var db = 'mongodb://localhost/27017';
mongoose.connect(db);
var server = app.listen(3000);
console.log("App is listening on port 3000");
Thanks.
Also, the url I'm trying to use inside of POSTMAN is http://localhost:3000/api/bears

Express processes requests Top-Down, meaning if you require a piece of functionality to be applied to all routes via middleware, than that middleware needs to be added to your app before any routes that require it. This is usually the case for middleware such as body-parser.
When using Router Middleware, you don't typically construct the router in the same file as the actual Express app that will use it as middleware. Instead, place it in a separate file and/or directory for organization purposes, this is considered a best practice.
Express Apps can be structured like so
/lib
/models
bear.js
product.js
/node_modules
/public
/css
/routes
api.js
package.json
server.js
The routes directory is where you would place any applicable Router Middleware files such as your api router. server.js is your main Express App and public is where your static assets are stored. lib is directory that contains any business logic files and models.
The actual Express app and Router files should look something like this
server.js
'use strict';
const express = require('express');
const bodyParser = require('body-parser');
const path = require('path');
const apiRouter = require('./routes/api');
const app = express();
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: true }));
app.use(express.static(path.join(__dirname, public)));
app.use(/api, apiRouter);
app.listen(port, () => {
console.log(`Listening on port ${port});
});
module.exports = app;
routes/api.js
'use strict';
const router = require('express').Router();
const Bear = require('./lib/models/bear');
router.use((req, res, next) => {
// logging happens here
console.log('Something will happen.');
next(); // Head to the next router...don't stop here
});
router.get('/', (req, res) => {
return res.json({ message: 'hooray! welcome to our api!'})
});
router.route('/bears')
//Create a bear (accessed at POST http://localhost:3000/api/bears)
.post((req, res) => {
var bear = new Bear(); // Create a new instance of the bear model
console.log(req);
bear.name = req.body.name; // set the bears name (comes from the request)
//res.send(200, req.body);
bear.save((err) => {
if (err)
return res.send(err);
return res.json({message: 'Bear Created!!'});
});
});
module.exports = router;
To note, you could break up your API even further to increase the amount of decoupling. An example of this would be to move the /api/bear route to its own router middleware and into its own route file. Then simply add it to your routes/api.js router as a middleware like you would in server.js. If your app is going to have a decent sized API, then this would be the best approach because it would allow the most flexibility when it comes to applying middleware to only certain routes and would make maintaining the source much easier.

express-subdomain not redirecting subdomain.localhost get request

I am using an express.js package called express-subdomain to facilitate requests to defined subdomains I set up.
As far as I understand, the subdomain constructor function expects an express router object which I pass to it from an exported router module.
What I have tried is as follows:
MAIN APP.JS SERVER FILE
var common = {
express: require('express'),
subdomain: require('express-subdomain')
};
common.app = common.express();
module.exports = common;
common.app.listen(3000, function () {
console.log(('app listening on http://localhost:3000'));
});
var router = require('./router/index');
// Error Handling
common.app.use(function(err, req, res, next) {
res.status(err.status || 500);
});
router/index
module.exports = function (){
var common = require('../app');
var router = common.express.Router();
common.app.get('/', function(req, res) {
res.send('Homepage');
});
common.app.use('/signup', require('./routes/signup'));
common.app.use(common.subdomain('login', require('./routes/login')));
}();
routes/login
var express = require('express');
var router = express.Router();
router.get('/', function (req, res) {
res.send('login working');
});
router.get('/info', function (req, res) {
});
module.exports = router;
I have tried to access the login subdomain at the following urls:
http://login.localhost
http://login.localhost:3000
http://login.localhost.com
http://login.localhost.com:3000
Any clarification or assistance appreciated.

author of express-subdomain here 👋
A couple of things:
Hosts must be setup correctly - I'd recommend something like so in your /etc/hosts file.
127.0.0.1 myapp.local
127.0.0.1 login.myapp.local
For more information on this see https://github.com/bmullan91/express-subdomain#developing-locally
Register the subdomain routes before any others, including the homepage route. The order is very important
The pattern you're using in /routes/index.js is not advised (requiring a self invoking function). Exporting the Router like you done in /routes/login.js is cleaner.
Finally, If you're still stuck take a look at the source for express subdomain and in particular its tests.
Happy coding.

Using Route of express node.js but express.Router getting as undefined

My code of router from default routes/index
/* GET home page. */
exports.index = function(req, res){
res.render('user', { title: 'Abcd' });
};
var express = require('express');
var router = express.Router();
/* GET home page. */
router.get('/', function(req, res) {
res.render('index', { title: 'Express' });
});
router.get('/helloworld', function(req, res) {
res.render('helloworld', { title: 'Hello, World!' })
});
module.exports = router;
getting error as can not call method get of undefined.I am new in node js please anyone help me.

Try upgrading to Express 4.x. You are probably running a 3.x flavor.

Router is a middleware of express which is registered implicitly with the express object the first time post() or get() is used. You can but don't have to add this explicitly calling use(), which allows you to register various middleware with express and so allows configuring processing and behavior in consideration of precedence.
Correct initialization and usage might look like this:
EDIT: Changed the example to be a "complete" http server.
app.js
var http = require('http');
var express = require('express');
// Requiring express exports a function that creates the application. Call it!
var app = express();
// Set port to listen to
app.set('port', process.env.PORT || 3000);
// Set view engine
app.set('view engine', 'jade');
// Tell express to use the router middleware
// Can be omitted if precedence doesn't matter
// (e.g. for loading static resources)
app.use(app.router);
// Add callback handler for home (/) route
app.get('/', function(req, res) {
res.render('index', { title: 'Express' });
});
// Create http server by passing "app" to it:
http.createServer(app).listen(app.get('port'), function() {
console.log('Express server listening on port ' + app.get('port'));
});
Now, if you place a minimal view into the default folder for views...
views/index.jade
doctype 5
html
head
meta(charset='utf-8')
title #{title}
meta(name='viewport', content='width=device-width, initial-scale=1.0')
body
div
h1 Gotcha! Title is "#{title}"
... and start your server from the console with...
$ node app.js
...you should have your first node/express/jade powered app up and running!