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Node.js v12.12.0 Documentation
Table of Contents
Usage & Example#
Usage#
node [options] [V8 options] [script.js | -e "script" | - ] [arguments]
Please see the Command Line Options document for more information.
Example#
An example of a web server written with Node.js which responds with
'Hello, World!'
:
Commands in this document start with $
or >
to replicate how they would
appear in a user's terminal. Do not include the $
and >
characters. They are
there to show the start of each command.
Lines that don’t start with $
or >
character show the output of the previous
command.
First, make sure to have downloaded and installed Node.js. See this guide for further install information.
Now, create an empty project folder called projects
, then navigate into it.
Linux and Mac:
$ mkdir ~/projects
$ cd ~/projects
Windows CMD:
> mkdir %USERPROFILE%\projects
> cd %USERPROFILE%\projects
Windows PowerShell:
> mkdir $env:USERPROFILE\projects
> cd $env:USERPROFILE\projects
Next, create a new source file in the projects
folder and call it hello-world.js
.
Open hello-world.js
in any preferred text editor and
paste in the following content:
const http = require('http');
const hostname = '127.0.0.1';
const port = 3000;
const server = http.createServer((req, res) => {
res.statusCode = 200;
res.setHeader('Content-Type', 'text/plain');
res.end('Hello, World!\n');
});
server.listen(port, hostname, () => {
console.log(`Server running at http://${hostname}:${port}/`);
});
Save the file, go back to the terminal window, and enter the following command:
$ node hello-world.js
Output like this should appear in the terminal:
Server running at http://127.0.0.1:3000/
Now, open any preferred web browser and visit http://127.0.0.1:3000
.
If the browser displays the string Hello, World!
, that indicates
the server is working.