We Keep Coding

ExpressJS: Best way to separate routes and accepting params?

I made a Express.js system where the files in the /routes folder are acting as a classic route (but with one file per route)
Example: /routes/get/user.js will be accessible with http://localhost:8080/user (the /get is to separate methods, it can be /post, /put...)
Here's my entire index.js file: https://pastebin.com/ALtSeHXc
But actually, my problem is that I can't pass params into the url like https://localhost:8080/user/random_id_here.
With this system, I think the best idea is to find a way to pass params on separated files too, but I don't know how can it be done...
Here's an example of one of my separated file:
module.exports = class NameAPI {
constructor(client) {
this.client = client
}
async run(req, res) {
// Code here
}
}
Maybe you'll have a better system, or a solution for this. Thanks.

You can get the optional params from the module object you already have so each module specifies its own params. This example below shows just adding new params on after the module name, but you could extend this feature to be richer if you needed to.
In a simple implementation, in your loader, you can change this:
posts.forEach((post) => {
const module = new (require(`./routes/post/${post}`))(this);
this.api.post(`/${post}`, async (req, res) => await module.run(req, res))
})
to this:
posts.forEach((post) => {
const module = new (require(`./routes/post/${post}`))(this);
const urlParams = module.params || "";
this.api.post(`/${post}${urlParams}`, async (req, res) => module.run(req, res))
});
So, if a given route wanted the extra URL param /:id added to it, then it would just define the .urlParams property on its exported module object to be `"/:id" and that would be automatically included in the route definition.
P.S. Most of the code in each of the branches of your switch statement in _loadHttpMethode() is identical. With a little factoring into a common function and one or two parameters passed to that function, you can eliminate all the copied code among those different branches of the switch so all each switch does is call one function and pass it a few arguments.

I generally would setup my express to handle this way in that case you want a dynamic insert. This is personal code so do make the adjustments necessary or observe the behavior! :)
WEBAPP.get('/room/:name', (req, res) => {
// Check if URL ends with / (in my case I don't want that)
if (req.url.endsWith('/')) return res.redirect('/');
// Check if URL param "name" matches my regex ex. Username1920 or redirect them
if (req.params.name.match(/^[a-zA-Z0-9]{3,24}$/) === null) return res.redirect('/');
// render the room (sending EJS)
res.render('room', {
title: req.params.name.toUpperCase()
});
});
/*
/*This example accepts one param and must follow my regex/rules*/
So if you were handed /room/test12345 your req.params.name would return a value. Notice the colon to define a param, so you could have /:room/:user/:request and it'd return:
req.params.room, req.params.user, req.params.request all defined! :)

How to seperate routes and parse request parameter in express API
You can just put all your different API methods for each model in a seperated folder, and then just parse the API routes in your main file.
Let's say we have one main file called app.js, and you can organize your API routes/endpoints in subfolders.
folder structure:
├── app.js
└── routes
└── api
└── users.js
users.js in the folder routes/api in this case contains all operations for your users endpoint, and you import this in your app.js file.
Based on the route examples defined below, this will let you parse your express API with these endpoints:
GET YOUR_API:PORT/users // fetch all users
GET YOUR_API:PORT/users/:userId // fetch single user by id
app.js
// this is just a demo app.js, please adapt to your needs
const express = require("express");
// express app
const app = express();
app.use(express.json());
// api routes
// endpoint No. 1, this will create the endpoint /users
// and will enable you to use all methods defined in file users.js
app.use("/users", require("./routes/api/users"));
// add more endpoints, example endpoint No. 2
app.use("/ENDPOINT_NAME", require("./routes/api/FILE_NAME"));
// handle everything else you need to handle in your main file
// run server
const PORT = process.env.PORT || 5000;
app.listen(PORT, () => console.log(`Server started on port ${PORT}`));
in subfolder routes/api you add your api route files, like so:
routes/api/users.js
const express = require('express');
const router = express.Router();
// here we only GET all users and user by id,
// but you can add any endpoints required for your API.
// get all users
router.get('/', async (req, res) => {
try {
// do something to get all users
const allUsers = // fetch all users, depends on how you want to do it
return res.status(200).json(allUsers)
} catch (err) {
console.log(err)
return res.status(400).json({ msg: 'Bad request.' })
}
})
// get a specific user by Id from request parameters
router.get('/:userId', async (req, res) => {
try {
// user id from params
const userId = req.params.userId
// do something with this userId, for example look up in DB
return res.status(200).json({userId: `Requested userId is ${userId}`})
)
} catch (err) {
console.log(err)
return res.status(400).json({ msg: 'Bad request.' })
}
})
// add more user endpoints here
// with router.post, router.put, router.delete, whatever you need to do
module.exports = router

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.

Node Express.js access variables from routes declared in separate files

I am currently developping a website that is using a lot of routes.
At the beginning, all the routes were implemented in a same file...
To make the things clearer, I decided to create multiple files, in order to separate the routes... using the Router module.
For example, in my users.js file I have:
var express = require('express');
var router = express.Router();
router.get('/', function(req, res, next) {
res.send('respond with a resource');
});
module.exports = router;
and in my main app.js file :
app.use('/users', require('./routes/user');
This works perfectly but the thing is that I would like my 'users' route
to access some variables that have been declared into the app.js file, before the app.use(...)
I know I can use require and module.exports, but some variables must be declared in my app.js, only one time, and I must access them from the routes I include.

You can pass them as a configuration object. Also change your route, to a function that returns a route, this way it can take parameters.
module.exports = function (options) {
return function (req, res, next) {
// do your thing
// you have access to options variable as well
}
}
And in your main JS file, require the file and call it, and pass all you need.
app.use('/users', require('./routes/user')({
option1: 'value1',
option2: 'value2'
}));
For things like database connection, your models and other third party libraries, you don't need to pass them as a configuration object. It is a good practice to move them to external files as well and require them in your routes' file. You need to decouple as much as modules you can.
Just keep that in mind that require will load every module once, the rest of the time, it just returns the reference to previously loaded module. Take a look at this question for more info.

For a more global access, you make the variables you want to share global.For example
//app.js
GLOBAL.config = {}
It's best to use a separate file for you application config. For example
//config.js
module.exports = {logging:true}
and make it a global variable in your app.js file as follow
//app.js
GLOBAL.config = require('./config');
Now it will be available in your routing definition. For example
//routes/users.js
router.get('/', function(req, res, next) {
if(config.logAccess){
var accessTime = new Date();
console.log('access at '+accessTime.toTimeString());
}
res.send('respond with a resource');
});

Handling routes with Angular and Express

I have an app where I am trying to remove the hashbang ( ! and #) prefixes for my routes, but still have people be able to use bookmarked routes. For the most part I have been able to get it work with html5Mode set to true, but there are a few cases where it is not working. Here is how I have my server configured:
var router = require('./router')(app);
app.use(express.static(path.join(__dirname, '../client')));
app.get('*', function (req, res, next) {
res.sendFile('index.html', {root:'../client/app/'});
});
router in this case looks like this:
var express = require('express');
var router = express.Router();
var Products = require('../../database').Products;
router.get('/:flavor', function (req, res) {
var flavor = req.params.flavor;
Products.findOne({flavor:flavor}, function (err, product) {
if (err) {
throw err
}
res.json(product);
});
Getting the flavor routes, is one case where this setup does not work. If someone directly types into the browse, mysite.com/lemon they receive the JSON data back, only (no template or anything). Normally this is used by the angular app, (which would typically make the request to /lemon and implement it into the template). However, if I move the router below the app.get('*'), then any request made by Angular for the data is returned with the entire index.html page. How can I make it so that a direct request by the browser for a route that normally returns JSON sends the index file?

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.