Node.js Documentation

This guide introduces Node.js programming theory, focusing on concepts and best practices for developers using the Codeunia Learn platform.

Overview

Node.js is a JavaScript runtime built on Chrome's V8 engine, enabling server-side JavaScript execution. It uses an event-driven, non-blocking I/O model for scalable network applications. Ideal for APIs, real-time apps, and microservices.

Node.js Fundamentals

Modules

Node.js uses CommonJS (require) or ES6 modules (import). Core modules include fs, http, path.

Asynchronous Programming

Callbacks, Promises, and async/await handle asynchronous operations. Event loop manages concurrency.

File System

The fs module provides synchronous and asynchronous file operations.

HTTP Server

Create servers with the http module. Express.js simplifies routing and middleware.

NPM and Packages

NPM manages dependencies. package.json defines project metadata and scripts.

Express.js

Express is a web framework for routing, middleware, and request handling.

APIs and REST

Build RESTful APIs with Express. Handle JSON data and HTTP methods.

Databases

Connect to databases like MongoDB (with Mongoose) or PostgreSQL (with pg).

Authentication

Implement auth with JWT, Passport.js, or OAuth.

Error Handling

Use try-catch, middleware, and process events for robust error management.

Testing

Frameworks like Jest and Mocha test Node.js applications.

Performance Optimization

Profile with tools like clinic.js. Use clustering for multi-core utilization.

Deployment

Deploy to platforms like Heroku, AWS, or Vercel. Use PM2 for process management.

Resources and References

• Node.js Official Documentation
• Express.js Guide
• NPM Documentation

Troubleshooting

Common issues include callback hell, memory leaks, and dependency conflicts. Use debugging tools and logging.

Development Setup

Install Node.js and NPM. Use editors with Node support. Set up version control and CI/CD.