QuickShip: High-Speed E-commerce Data Aggregation

QuickShip is a high-speed e-commerce data aggregation service that concurrently fetches product data (price, inventory, promotions) from multiple microservices to deliver lightning-fast API responses.
It uses Go’s Fan-Out / Fan-In concurrency pattern to drastically cut latency.

Toolkit guide

🚀 Why QuickShip Exists

Modern e-commerce platforms depend on several microservices to compute real-time product information.
Calling them one-by-one is too slow.

QuickShip solves this by:

• Running all service calls in parallel
• Returning results as fast as the slowest service
• Ensuring consistent, low-latency API responses

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🎯 Performance Breakdown

🐢 Sequential Execution (Slow)

50ms + 200ms + 400ms = 650ms

⚡ Concurrent Execution (QuickShip Speed)

~400ms (determined by the slowest service)

Service Latencies

Service	Latency
fetchPromotionsSimulates	50ms
fetchPriceSimulates	200ms
fetchInventorySimulates	400ms

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🧩 Architecture Diagram (Fan-Out / Fan-In)

     ┌────────────────┐

Request  →   │ GetCartSummary │
└───────┬────────┘
│
(Fan-Out: Launch workers)
▼
┌──────────────┬──────────────┐
▼              ▼              ▼
Promotions     Price Service    Inventory
Worker          Worker          Worker
(50ms)           (200ms)         (400ms)
└──────────────┬──────────────┘
│
(Fan-In: Combine)
▼
Final Cart Summary JSON

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🛠️ Prerequisites

• Go 1.18+
• Gorilla Mux router

  go get github.com/gorilla/mux

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▶️ Running the Server

Place main.go and main_test.go in your project directory.

Start the application:

go run main.go

Open in browser or Postman:

http://localhost:8080

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⚡ Testing the Speed

Run:

curl http://localhost:8080/cart/summary/SKU-REFAC-TEST

Expected Response (~400ms total):

[Quickship_api] (https://go-quickship.onrender.com/cart/summary/32)

{
  "product_id": "SKU-REFAC-TEST",
  "final_price": 49.99,
  "available_stock": 120,
  "promotion_message": "Buy 1 Get 1 Half Off!",
  "total_time_ms": 405
}

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🧪 Running Unit Tests

go test -v .

Tests verify:

• Correct data returned
• Concurrency reduces execution time

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📂 Project Structure

QuickShip/
├── main.go
├── main_test.go
├── go.mod
└── go.sum

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📜 License

📜 License You are free to use, modify, and distribute this project.