Backend Development Learning Journey

Documenting my path into backend development, starting with Node.js fundamentals.

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📖 Table of Contents

• Current Learning Progress
• Key Concepts Learned
• Learning Notes
• Next Learning Goals

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🚀 Current Learning Progress

Node.js Core Concepts

• JavaScript Runtime Environment (01_script.js)
• Module Systems (CommonJS & ES) (03_moduleExport.js, 05_import.js)
• NPM & Package Management (04_npm.js)
• Command Line Arguments (02_processArgv.js)
• Basic Math Operations (math.js)

Express.js

• Basic Express Server
• HTTP Methods (GET, POST)
• Route Parameters
• Query Strings
• Static Files

EJS Templates

• Template Engine Setup
• Dynamic Content Rendering
• Loops & Conditionals
• Partials & Includes
• Passing Data to Views

Object-Oriented Programming

• OOP Basics (01_OOPS.js)
• Object Prototypes (02_objectPrototypes.js)
• Factory Functions (03_factoryFunctions.js)
• Constructor Functions (04_newOperator.js)
• ES6 Classes (05_classes.js)
• Inheritance & Polymorphism (06_inheritance.js)

RESTful API Development

• REST Architecture Principles
• CRUD Operations
• RESTful Routes Pattern
• Resource Naming Conventions
• Client-Server Integration (public/script.js)
• View Templates
  • Index View (views/index.ejs)
  • Show View (views/show.ejs)
  • Create View (views/new.ejs)
  • Edit View (views/edit.ejs)

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💡 Key Concepts Learned

Module Systems

CommonJS Style

// math.js
const add = (a, b) => a + b;
const subtract = (a, b) => a - b;

module.exports = { add, subtract };

// Using in another file
const mathOperations = require('./math');
mathOperations.add(5, 3);

ES Module Style

// Using ES import/export
import { PI, g } from './math.js';
console.log(PI, g);

Command Line Arguments

// Reading user inputs from terminal
const args = process.argv.slice(2);
console.log('User provided:', args);

Express Server Setup

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

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

app.listen(3000);

EJS Template Usage

app.set('view engine', 'ejs');

app.get('/home', (req, res) => {
    res.render('home', { name: 'World' });
});

OOP Concepts

Classes and Objects

class User {
    constructor(username, email) {
        this.username = username;
        this.email = email;
    }
    
    getInfo() {
        return `${this.username} (${this.email})`;
    }
}

const user = new User('john', 'john@example.com');

Inheritance

class Admin extends User {
    constructor(username, email, role) {
        super(username, email);
        this.role = role;
    }
}

RESTful Routes Pattern

// Basic REST routes setup
app.get('/resources', (req, res) => {
    // Index - Show all resources
});

app.post('/resources', (req, res) => {
    // Create - Add new resource
});

app.get('/resources/:id', (req, res) => {
    // Show - Display specific resource
});

app.put('/resources/:id', (req, res) => {
    // Update - Modify existing resource
});

app.delete('/resources/:id', (req, res) => {
    // Delete - Remove resource
});

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📝 Learning Notes

Core Understanding

What is Node.js?

• Node.js executes JavaScript outside browser
• Uses V8 JavaScript engine
• Enables server-side JavaScript

Module Patterns

• CommonJS module system
• ES module implementation
• Directory-based modules (Fruits example)

Package Management

• NPM basics
• Installing and using packages (Figlet example)
• Package.json structure

Express Framework

• Web application framework
• Routing system
• Middleware concept
• Request/Response cycle

EJS Template Engine

• Dynamic HTML generation
• Template syntax (<%= %>)
• Includes & partials
• Data passing to views

Object-Oriented Programming

• Class-based vs Prototype-based OOP
• Constructor functions and 'new' operator
• Inheritance patterns in JavaScript
• Factory function patterns
• 'this' keyword behavior
• Prototypal inheritance chain

RESTful API Design

• Resource-based routing
• HTTP methods semantics (GET, POST, PUT, DELETE)
• Route naming conventions
• Client-server architecture
• Stateless communication
• CRUD operations mapping
• View templates organization

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🎯 Next Learning Goals

1. Database Integration
2. Authentication & Authorization
3. API Security
4. Error Handling
5. Advanced Design Patterns

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Started: October 2025
Last Updated: October 2025

Learning and documenting every step of the way 🚀