🔗 URL Shortener

A production-ready URL shortener API written in TypeScript. Short codes are generated and persisted in MongoDB; Redis sits in front for cache-first lookups. The project follows a layered architecture with dependency injection via tsyringe.

Live: https://url-shortener-mhp8.onrender.com

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Features

• Shorten any valid URL to a 5-character code
• Cache-first reads: Redis checked before hitting MongoDB
• Input validation with Zod
• Dependency injection via tsyringe
• /health endpoint for uptime monitoring
• Landing page with a built-in shortener form at /
• Self-healing: a 5-minute health ping prevents Render cold starts

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API

Method	Route	Description
GET	/	Landing page with shortener form
GET	/health	Service health check
POST	/	Create a short URL
GET	/:shortCode	Redirect to the original URL

Create a short URL

Request:

POST /
Content-Type: application/json

{
  "longUrl": "https://example.com/some/very/long/path"
}

Response 201:

{
  "shortUrl": "aB3xZ"
}

Status codes:

Code	Meaning
201	Short URL created
422	Validation failed (invalid URL)
404	Short code not found
500	Internal server error

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Tech Stack

Layer	Technology
Language	TypeScript
Framework	Express
Database	MongoDB (persistent store)
Cache	Redis (cache-first lookup)
Validation	Zod
DI Container	tsyringe
Deploy	Render

Request flow

Client
  │
  ├─ POST / ──────────────► Controller → Service → Repository
  │                                                    │
  │                                               [Redis hit?]
  │                                                Yes │ No
  │                                                    │  └─► MongoDB → cache in Redis
  │                                                    │
  └─ GET /:code ──────────► Redirect to longUrl ◄──────┘

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Project Structure

Controllers/    Request handling and input validation
Services/       Business logic
Repositories/   MongoDB and Redis data access
Interfaces/     Contracts and type definitions
Models/         Mongoose schemas
Routes/         Express route definitions
config/         Database and cache initialization
container.js    tsyringe dependency injection setup
index.ts        App entry point

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Quick Start

1. Clone & Install

git clone https://github.com/NeverSpot/URL-shortener-.git
cd URL-shortener-
npm install

2. Configure Environment

Create a .env file in the project root:

PORT=3001
MONGO_URI=mongodb://localhost:27017
DB_NAME=url_shortener
REDIS_USERNAME=
REDIS_PASSWORD=
REDIS_HOST=127.0.0.1
REDIS_PORT=6379

3. Run

# Build and start
npm run build
npm start

# Development (ts-node / nodemon)
npm run dev

Server runs at http://localhost:3001.

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Try It

Check health:

curl https://url-shortener-mhp8.onrender.com/health

Shorten a URL:

curl -X POST https://url-shortener-mhp8.onrender.com/ \
  -H "Content-Type: application/json" \
  -d '{"longUrl": "https://example.com/some/long/path"}'

Visit https://url-shortener-mhp8.onrender.com/<shortCode> to be redirected.

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License

ISC