Martin xtools-at

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

Sometimes we need to run multiple nodejs app on same server with different domain or sub domain like admin.domain.com, api.domain.com and also need to run both nodejs or reactjs app concurrently. We can do this using 2 things , first of all we need to install nginx in our server for reverse proxy to connect different domain, and for running multiple nodejs app concurrently we can use PM2 NodeJs Process Manager

Please Make sure that you have installed these things on your server

NodeJS

E-Commerce c-lightning node on Digital Ocean

Prerequisites

based on small Digital Ocean VPS (1CPU / 1GB RAM) with Ubuntu 16.04
SSH keys are recommended, but not described here
(sub) domain name necessary for SSL certificate

UFW & basic stuff

Login as "root"

Simple snake game in JS.

Unfinished features & unaddressed issues:

No collision detection (no win/loss)
Pressing two directions in quick succession allows the snake to reverse direction on itself. (This is an issue with the FPS limiting vs. event-driven key handling.)
Food can spawn on top of the snake.

-#!/usr/bin/env bash
-################ Description: ###################
-# This script will disable all opt-out under
-# Ubuntu 22.04 (Codename: Jammy Jellyfish).
-# At first the telemetry domains will be resolved
-# to the local host and second all telemetry services
-# will be removed from the system.
-# The following work has a system-wide effect not just

	// node --experimental-json-modules read.mjs
	// node 17 only

	import { ethers } from "ethers";
	import { readFile } from "fs/promises";
	import ERC20ABI from "./ERC20.json" assert { type: "json" };

	const privateKey = await readFile("key.txt", { encoding: "utf-8" });
	const rpcclient = new ethers.providers.WebSocketProvider(
	"wss://stardust-ws.metis.io/"

	pragma solidity ^0.4.19;
	contract ERC721 {
	string constant private tokenName = "My ERC721 Token";
	string constant private tokenSymbol = "MET";
	uint256 constant private totalTokens = 1000000;
	mapping(address => uint) private balances;
	mapping(uint256 => address) private tokenOwners;
	mapping(uint256 => bool) private tokenExists;
	mapping(address => mapping (address => uint256)) private allowed;
	mapping(address => mapping(uint256 => uint256)) private ownerTokens;

	package main

	import (
	"fmt"
	"syscall"
	//~ "time"
	"unsafe"
	"golang.org/x/sys/windows"
	)

	/* demonstrating uint overflow and underflow in ethereum solidity
	this is why you need guards like:
	if (balances[_to] + _amount < balances[_to]) throw;
	*/
	contract C {
	// (2**256 - 1) + 1 = 0
	function overflow() returns (uint256 _overflow) {
	uint256 max = 2**256 - 1;
	return max + 1;
	}

	// just add pass server as your task function

	// Start a server with LiveReload to preview the site in
	const OUTPUT_PARENT = 'dist'
	const OUTPUT_DIRECTORY = OUTPUT_PARENT + '/browser-sync'

	function server(done) {
	browser.init({
	server: {
	directory: true,