Node.js Factory Defense

🎮 How to Play

🎯 Objective

Defend your factory from enemy bugs! Write Node.js code to attack them and earn XP!

Controls

Desktop: WASD or Arrow keys to move
Mobile: Use joystick (bottom-left)
CODE Button: Opens code challenge
LEARN Button: Shows lesson before challenge
REF Button: Quick reference guide
HELP Button: Shows tips

📖 Learning Modes

Read Lesson: Understand the concept first
See Example: View working code
Multiple Choice: Easy mode for beginners
Write Code: Advanced mode

⚔️ Combat

When enemies attack your buildings:

Red warning appears on screen
Click LEARN to understand the concept
Then click CODE to solve the challenge
Buildings lose HP if you're too slow

📇 Node.js Quick Reference

Variables

const name = 'Tech';  // constant
let count = 10;        // can change
var old = 5;           // old style
            

💬 Console Output

console.log('Hello');
console.error('Error!');
console.warn('Warning!');
            

⚙️ Functions

function greet(name) {
  return 'Hello ' + name;
}

// Arrow function
const add = (a, b) => a + b;
            

📋 Arrays

const arr = [1, 2, 3];
arr.push(4);           // add
arr.pop();             // remove last
arr.map(x => x * 2);  // transform
            

🗂️ Objects

const user = {
  name: 'John',
  age: 25,
  greet() { return `Hi ${this.name}`; }
};
            

Modules

const fs = require('fs');
const path = require('path');
const http = require('http');
            

🌐 HTTP Server

const http = require('http');
const server = http.createServer((req, res) => {
  res.writeHead(200);
  res.end('Hello World');
});
server.listen(3000);
            

⚡ Express.js

const express = require('express');
const app = express();

app.get('/', (req, res) => {
  res.send('Hello');
});

app.listen(3000);
            

⏳ Async/Await

async function readData() {
  try {
    const data = await fs.readFile('file.txt');
    console.log(data);
  } catch(err) {
    console.error(err);
  }
}
            

🗄️ Database (MongoDB)

const mongoose = require('mongoose');
mongoose.connect('mongodb://localhost:27017/mydb');

const User = mongoose.model('User', {
  name: String,
  email: String
});
            

🧠 Node.js Challenge

💻 Study this working example:

Not sure how to write it? The buttons above build the code one piece at a time and explain every piece. You stay in control — just click, read the note, then try writing it yourself.

🔍 What your code MUST contain — every box shows the exact line to type. Click a line to drop it into the editor.

💥 Stuck happens to everyone.

Nobody writes working Node.js on the first try. Read the answer, copy it line by line, then erase it and type it out yourself — that is how it sticks. Nothing is lost: you can still submit your own version afterwards.

🧠 Blind mode is on. No exact lines, no build steps, no answers. Write the program from memory.

💻 Now run it on your own computer

Install Node.js from nodejs.org (it is one installer, like installing Chrome).
Open Command Prompt on Windows (or Terminal on Mac).
cd Desktop — go to the folder where you saved the file.
Save your code in a file called app.js. The .js ending is what marks it as JavaScript.
Run it: node app.js — your console.log text prints in the terminal.
Change something, save the file, run it again. That loop is how everybody learns.

📦 Installing packages with npm

npm ships with Node.js, so you already have it. Type npm -v to check.
A project has a file called package.json listing its name, version and dependencies.
npm install express downloads a package and writes it into package.json.
Then const express = require('express'); loads it. require is how Node.js reads a package or another file.

🏭 Node.js Factory Defense

⚠️ ENEMY ATTACK!

💥 Stuck happens to everyone.

💻 Now run it on your own computer

📦 Installing packages with npm

FACTORY DESTROYED