codefoster

I’ll start with the code…

require('express')().get('/',function(req,res){

    res.send('hello world');

}).listen(3000);

There it is. The simplest Node.js webserver/website. Three lines of code.

I know I’ve got it a bit mungled together. I’m not recommending this code. Just having fun.

Notice that I’m hanging a () directly off of the require('express'). The require statement returns a function. This is one of the most popular of the Node module patterns. Since it returns a function, hanging parenthesis off of it executes the function.

The execution of the function returns an express app, and the app supports chaining like jQuery or LINQ, so you do a .get() and then a .listen() and those are both methods of an express app.

The .get() creates the root route ('/') and then allows you to provide a function to handle that route. The function does a simple hello world.

The .listen() starts up the engine.

After creating a JavaScript file called app.js with this content in it, just type node app, and you should get zero feedback. But then hit http://localhost:3000 in your browser of choice and you’ll get the reassuring “hello world”.

By the way, if you’re using ES2015, that gets even shorter…

require('express')().get('/',(req,res)=>res.send('hi')).listen(3000);