URL Shortener Backend

A simple and efficient URL shortener API built with Express.js, TypeScript, and SQLite.

Features

• 🔗 URL Shortening: Convert long URLs into short, shareable links
• 📊 Analytics: Track click counts and usage statistics
• 🔄 Smart Redirects: Automatic redirection with click tracking
• 🛡️ Input Validation: Validates URL format before shortening
• 📱 RESTful API: Clean, standard HTTP endpoints
• ⚡ Fast Lookups: SQLite database for quick URL resolution
• 🔧 Environment Config: Configurable port and base URL

Tech Stack

• Express.js - Web framework
• TypeScript - Type safety
• SQLite3 - Lightweight database
• nanoid - Short code generation
• ESLint + Prettier - Code quality

Quick Start

Prerequisites

• Node.js (v18 or higher)
• pnpm (recommended) or npm

Installation

1. Clone the repository:

git clone <repository-url>
cd be

2. Install dependencies:

pnpm install

3. Start the development server:

pnpm dev

The server will start at http://localhost:3000

API Endpoints

Create Short URL

POST /shorten
Content-Type: application/json
{"url": "https://www.google.com"}

# Response:
{
  "shortCode": "abc123",
  "shortUrl": "http://localhost:3000/abc123",
  "originalUrl": "https://www.google.com",
  "clickCount": 0,
  "createdAt": "2024-01-01T00:00:00.000Z"
}

Redirect to Original URL

GET /abc123
# → Redirects to https://www.google.com
# → Increments click count

Get All URLs

GET /api/urls
# Returns list of all shortened URLs with stats

Get URL Statistics

GET /api/stats/abc123
# Returns detailed stats for specific short code

Delete URL

DELETE /api/urls/abc123
# Removes the short URL from database

Environment Variables

Create a .env file based on env.example:

PORT=3000
BASE_URL=http://localhost:3000
DATABASE_PATH=./urls.db
SHORT_CODE_LENGTH=4

Development

Available Scripts

• pnpm dev - Start development server
• pnpm lint - Check for linting errors
• pnpm lint:fix - Auto-fix linting errors
• pnpm format - Format code with Prettier
• pnpm format:check - Check if code is formatted

Database Schema

urls (
  id INTEGER PRIMARY KEY AUTOINCREMENT,
  shortCode TEXT UNIQUE,      -- 4-character short code
  originalUrl TEXT,           -- Full original URL
  createdAt DATETIME,         -- Creation timestamp
  clickCount INTEGER,         -- Number of redirects
  lastClickedAt DATETIME      -- Last redirect time
)

License

ISC