Node.js Built-in Modules Exercises

A comprehensive collection of Node.js exercises demonstrating the use of built-in modules, specifically readline and fs modules with modern promise-based APIs.

📚 Projects Overview

Readline Module Exercises

1. node-readline-1 - Personalized Greeting

• Files: index.js (CommonJS), index.mjs (ES6 modules)
• Features: Interactive name input with personalized greeting
• Technologies: readline, process

2. node-readline-2 - Interactive Input Examples

• Files: index.js, index-async.js
• Features: Basic readline usage and async patterns
• Technologies: readline, process

3. node-readline-3 - Password Validation

• Files: index.js (CommonJS), index.mjs (ES6 modules)
• Features: Password validation with criteria checking
• Technologies: readline, process
• Validation: Minimum length, uppercase, lowercase letters

4. node-readline-4 - Number Guessing Game

• Files: index.mjs
• Features: Interactive number guessing with retry mechanism
• Technologies: readline/promises, process
• Game Logic: Random number generation, attempt tracking, input validation

5. node-readline-5 - User Information Collection

• Files: index.mjs
• Features: Multi-field form with comprehensive validation
• Technologies: readline/promises, process
• Validation: Name, age, email validation with retry mechanism

File System Module Exercises

1. node-fs-1 - File Operations

• Files: index.js, create.js, sample.txt, output.txt
• Features: File reading and writing operations
• Technologies: fs, path
• Operations: readFile(), writeFile()

2. node-fs-3 - Directory Listing

• Files: index.mjs
• Features: Directory contents listing with error handling
• Technologies: fs/promises, path
• Operations: readdir() with async/await

3. node-fs-4 - Interactive File Reader

• Files: index.mjs
• Features: Interactive file reading with user input
• Technologies: readline/promises, fs/promises
• Features: User-friendly interface, error handling

4. node-fs-5 - Digital Diary Application

• Files: index.mjs, diary.txt
• Features: Complete diary application with timestamps
• Technologies: readline/promises, fs/promises
• Features: Read/Write entries, automatic timestamps, input validation

🚀 Key Features Demonstrated

Modern JavaScript Patterns

• ✅ ES6 Modules with import/export
• ✅ Async/Await syntax for clean asynchronous code
• ✅ Promise-based APIs (fs/promises, readline/promises)
• ✅ Error Handling with try/catch blocks

Node.js Built-in Modules

• ✅ Readline Module: Interactive command-line interfaces
• ✅ File System Module: File and directory operations
• ✅ Process Module: Standard input/output handling
• ✅ Path Module: Cross-platform file path handling

Best Practices

• ✅ Input Validation: Comprehensive user input checking
• ✅ Error Handling: Graceful error management
• ✅ User Experience: Clear prompts and feedback
• ✅ Code Organization: Modular function design
• ✅ Resource Management: Proper cleanup of interfaces

🛠️ Technologies Used

• Node.js - Runtime environment
• JavaScript ES6+ - Modern JavaScript features
• CommonJS - Traditional Node.js module system
• ES6 Modules - Modern module system
• Promises - Asynchronous programming
• Async/Await - Clean asynchronous syntax

📁 Project Structure

act-node-built-in-modules/
├── node-readline-1/          # Personalized greeting
├── node-readline-2/          # Interactive input examples
├── node-readline-3/          # Password validation
├── node-readline-4/          # Number guessing game
├── node-readline-5/          # User information collection
├── node-fs-1/               # File operations
├── node-fs-3/               # Directory listing
├── node-fs-4/               # Interactive file reader
├── node-fs-5/               # Digital diary application
└── README.md                # This file

🎯 Learning Outcomes

After completing these exercises, you will understand:

1. Readline Module: How to create interactive command-line applications
2. File System Module: How to read, write, and manage files and directories
3. Promise-based APIs: Modern asynchronous programming patterns
4. Error Handling: Robust error management in Node.js applications
5. Input Validation: Ensuring data integrity in user applications
6. Module Systems: Both CommonJS and ES6 module patterns

🏃‍♂️ Running the Projects

Each project can be run independently:

# Navigate to any project folder
cd node-readline-1

# Run CommonJS version
node index.js

# Run ES6 modules version (if available)
node index.mjs

# Or use npm scripts
npm start

📝 Notes

• All projects include comprehensive error handling
• Input validation is implemented where appropriate
• Both CommonJS and ES6 module patterns are demonstrated
• Modern promise-based APIs are used throughout
• User-friendly interfaces with clear feedback

🤝 Contributing

This is a learning project demonstrating Node.js built-in modules. Feel free to explore the code and experiment with modifications!

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Created as part of Node.js learning journey 🚀