Online Course Overview

Learn Node.js

Learn Node.js online through our comprehensive course. Build scalable backend applications and REST APIs using JavaScript.

65 Lessons in 25 Sections

Intermediate → Advanced

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Curriculum

01Introduction

What is Node.js?

Node.js is a runtime that allows you to run JavaScript on the server.

Browser vs Node.js

Node.js doesn't have DOM APIs (no window or document), but it adds server APIs (file system, http).

The V8 Engine

Node.js is built on Google Chrome's V8 JavaScript engine for high-performance execution.

Event-Driven Architecture

Node.js relies heavily on events rather than traditional threading.

Non-blocking I/O

Node.js does not wait for file or network operations to finish before moving to the next line of code.

Node.js vs PHP

Understand the architectural differences between Node.js and traditional web backends like PHP.

02Installation & Running

Running Scripts

You execute JavaScript files using the `node` command in your terminal.

The process Object

The `process` object provides information about the current Node.js process.

Command Line Arguments

`process.argv` contains the command-line arguments passed when the Node process was launched.

Exit Codes

Use `process.exit()` to terminate the process and return a status code to the OS.

03Project Structure

Understanding package.json

`package.json` is the manifest file for any Node.js project.

npm Scripts

Define reusable command-line tasks in `package.json`.

04Packages

Installing Packages

npm allows you to download and use third-party code from the npm registry.

Dev Dependencies

Separate packages needed only for building or testing your app.

05Modules

CommonJS (require)

The legacy module system in Node.js.

ES Modules (import)

The modern, standard JavaScript module system. Enable via `"type": "module"` in package.json.

06Core Modules

Built-in Modules

Node.js ships with several built-in modules for interacting with the OS.

Path Module

Safely construct and manipulate file paths across different operating systems.

URL Module

Easily parse and construct URLs.

Crypto Module

Generate UUIDs, hashes, and secure random numbers.

Child Processes

Execute system shell commands from within Node.js.

07File System

Reading Files

Read the contents of a file asynchronously.

Writing Files

Write data to a file, replacing it if it already exists.

Appending Files

Add data to the end of an existing file.

Working with Directories

Create, read, and manage folders.

08Async Programming

Callbacks

The oldest way Node.js handled async tasks. Can lead to "callback hell".

Promises

A cleaner way to chain async operations.

Async / Await

Syntactic sugar over Promises, making async code look synchronous.

Parallel Execution

Run multiple asynchronous tasks simultaneously to save time.

Promisify

Convert older callback-based APIs into Promise-based APIs.

09HTTP Servers

The HTTP Module

Create a native web server without external frameworks.

Basic Routing

Respond differently based on the URL requested.

Headers and Status Codes

Send metadata and HTTP status codes to the client.

Parsing Request Bodies

Native Node.js requires streaming the request body manually.

Fetch API in Node

Node.js 18+ includes the native `fetch` API for making outbound HTTP requests.

Middleware Concepts

Functions that execute sequentially during an HTTP request cycle.

10REST APIs

REST API Concepts

Representational State Transfer maps HTTP verbs to CRUD operations.

API Error Handling

Return appropriate 4xx and 5xx status codes for failures.

11Node Ecosystem

Web Frameworks (Express)

While Node has a native `http` module, most developers use frameworks like Express.js for easier routing and middleware.

12Environment Configuration

process.env

Read environment variables to configure your application dynamically.

Using .env Files

Load variables from a `.env` file during development (never commit this file).

13Node + MongoDB

Connecting to MongoDB

Use the official MongoDB driver to connect your Node app to a database.

MongoDB CRUD in Node

Execute queries natively from your backend.

14Node + SQL

Connecting to SQL

Connect Node to PostgreSQL, MySQL, or SQLite using specific drivers.

Preventing SQL Injection

Always use parameterized queries to protect against malicious input.

15Full-Stack Architecture

React + Node Integration

Your React frontend makes HTTP requests to your Node.js backend to fetch and mutate data.

CORS (Cross-Origin Resource Sharing)

Browsers block cross-origin requests by default. The server must explicitly allow them via headers.

16Authentication

Authentication Architecture

A secure process for verifying user identity without storing raw passwords.

Password Hashing (bcrypt)

Never store plain-text passwords. Hash them with a salt.

JSON Web Tokens (JWT)

Stateless authentication where the user's identity is encoded in a signed token.

17Security

Security Headers

HTTP headers that instruct the browser to enforce security policies.

Rate Limiting

Prevent abuse and DDoS attacks by limiting requests per IP address.

Input Validation

Never trust user input. Validate everything before it touches your database.

18Streams & Buffers

Buffers

Buffers represent fixed-length sequences of raw binary data.

Streams

Streams process data piece by piece, allowing you to handle massive files without running out of memory.

19Events

EventEmitter

Decouple different parts of your application using publish-subscribe patterns.

20Testing

Testing Node.js Applications

Use Node's built-in `assert` module (or test runners like Jest/Mocha) to write unit tests.

21Debugging

Debugging Node.js

Use the `--inspect` flag to debug Node apps using Chrome DevTools.

Memory Leaks

Learn how variables retained in memory can crash long-running backend processes.

22Production

Production Architecture

Structure enterprise apps properly rather than dumping everything in one file.

Process Management (PM2)

Keep your Node.js app alive, automatically restart it if it crashes, and utilize multiple CPU cores.

Graceful Shutdown

Ensure database connections and current requests finish before shutting down the server.

23Advanced Async

Event Loop Phases

The event loop has distinct phases: timers, pending callbacks, poll, check, and close callbacks.