forinda

Node.js Deployment

Steps to deploy a Node.js app to DigitalOcean using PM2, NGINX as a reverse proxy and an SSL from LetsEncrypt

1. Sign up for Digital Ocean

If you use the referal link below, you get $10 free (1 or 2 months) https://m.do.co/c/5424d440c63a

2. Create a droplet and log in via ssh

I will be using the root user, but would suggest creating a new user

forinda

Deploy Node.js Application to DigitalOcean

This step by step tutorial will show you how to set up a Node.js server with MongoDB to DigitalOcean using PM2, NGINX as reverse proxy and a SSL from LetsEncrypt. We will also add a custom domain name.

Prerequisites

• Download PuTTY & PuTTYgen
• Download WinSCP
• Have your application on a GitHub repo.

Create Droplet & Generate SSH Key

forinda

Ubuntu/Kali/Zorin setup with proxy environment

Once you've installed your os of debian distribution you need to take not of the following.

If you are operating in a proxy environment, there are two layers of proxy, i.e root, session and user level proxy For user level we can add proxy in the /etc/environment file where it can be read by some applications or use the network GUI

Ubuntu: Settings > Network > Network Proxy > Manual path

This applies for kde plasma and gnome desktop environment

forinda

deb http://archive.ubuntu.com/ubuntu/ focal main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ focal main restricted universe multiverse

deb http://archive.ubuntu.com/ubuntu/ focal-updates main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ focal-updates main restricted universe multiverse

deb http://archive.ubuntu.com/ubuntu/ focal-security main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ focal-security main restricted universe multiverse

deb http://archive.ubuntu.com/ubuntu/ focal-backports main restricted universe multiverse

forinda

##Longest Substring with At Most K Distinct Characters
var lengthOfLongestSubstringKDistinct = function(s, k) {
    //incase the length of the string is the same or less than the distict number then return the length of the string.
    if(k >= s.length ){
        return s.length;
    }
    //define an empty hash map variable.
    let hmap = {}
    let max = 0;
    //iterating through the string.

forinda

##Longest Substring with At Most K Distinct Characters
var lengthOfLongestSubstringKDistinct = function(s, k) {
    //incase the length of the string is the same or less than the distict number then return the length of the string.
    if(k >= s.length ){
        return s.length;
    }
    //define an empty hash map variable.
    let hmap = {}
    let max = 0;
    //iterating through the string.