🔗 High-Performance URL Shortener System

A scalable, high-performance URL shortener backend API built with modern technologies. This system is designed for low-latency redirects, real-time analytics, and resilience under heavy load, leveraging Redis for caching and MongoDB for flexible data storage.

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📊 System Architecture

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🚀 How to Run

🔧 1. Start All FastAPI Servers (Ports 8000, 8001, 8002)

./run_all.sh

This starts 3 FastAPI instances to simulate a load-balanced backend.

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🧪 2. Run Locust Load Test (2000 Users)

./run_stress_test.sh

Or manually:

locust -f app/locustfile.py \
  --headless \
  -u 2000 \
  -r 500 \
  --run-time 3m \
  --csv=results/loadtest \
  --host=http://localhost

Outputs will be saved in results/:

• loadtest_stats.csv
• loadtest_failures.csv
• loadtest_stats_history.csv

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🧪 3. Run Unit Tests

pytest tests/

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🛠 Tech Stack

• FastAPI – high-speed async web server
• MongoDB – stores long-to-short URL mappings
• Redis – caches hot URL entries and tracks view counts
• Locust – load testing framework for HTTP users
• Uvicorn – ASGI server with multiple workers
• Pytest – test framework for backend APIs

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📌 API Endpoints

Method	Endpoint	Description
POST	/shorten	Shorten a long URL
GET	/{short_id}	Retrieve the original long URL
GET	/analytics/{short_id}	View access stats for a short URL

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✨ Future Improvements

• User authentication and rate limiting
• QR code generation
• Geo-based analytics
• Full deployment with Docker and reverse proxy
• Horizontal scaling with MongoDB + Redis clustering

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