Introduction

Node.js is a JavaScript runtime built on Chrome's V8 JavaScript engine. Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient. Node.js' package ecosystem, npm, is the largest ecosystem of open source libraries in the world. In this article we will explain the steps of installing node.js and npm in CentOS.

Step 1: Add node.js yum repository

First we need to add yum repository of node.js to our system which is sourced from nodejs' official website. Run the following commands in succession to add the yum repository.

yum install -y gcc-c++ make
curl -sL https://rpm.nodesource.com/setup_6.x | sudo -E bash -
Copy code

如果报错如下：

Error: Failed to download metadata for repo 'nodesource': Cannot download repomd.xml: Cannot download repodata/repomd.xml: All mirrors were tried

尝试执行如下命令解决

sudo rm -r /var/cache/dnf

依然不行，去官网查看新版本的重新尝试。

Welcome to Node.js RPM repository

Step 2: Install node.js and NPM

Now it's time to install the node.js package and NPM package. Run the following command to do so. This single command will install node.js, npm and also other dependent packages.

yum install nodejs
Copy code

Step 3: Verify versions

Having installed the packages, you need to check their versions.

For checking node.js version:

node -v

#output
v6.9.4
Copy code

For checking npm version:

npm -v

#output
3.10.10
Copy code

Step 4: Testing the installation

You can test your installation by creating a test file, say test_server.js

vim test_server.js
Copy code

Then add the following content in the file.

var http = require('http');
http.createServer(function (req, res) {
res.writeHead(200, {'Content-Type': 'text/plain'});
res.end('Welcome');
}).listen(3001, "127.0.0.1");
console.log('Server running at http://127.0.0.1:3001/');
Copy code

Now start the web server using the below command

node --debug test_server.js

debugger listening on port 5858
Server running at http://127.0.0.1:3001/
Copy code

Web server has started which can be accessed using URL http://127.0.0.1:3001/ in your browser.

How to install Node.js and NPM on CentOS

如果报错如下：

尝试执行如下命令解决