🚀 Backend Assignment - Pincode Distance API

📌 Overview

This project is a REST API that calculates the distance and duration between two pin codes using the Google Maps API. The API is designed to be REST-compliant, supports caching, and stores the distance and duration data in a database.

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🛠 Features

• ✅ Fetches route, distance, and duration between two pin codes.
• ✅ Caches responses to reduce unnecessary API calls to Google Maps.
• ✅ Saves distance, duration, and route information in a database.
• ✅ Uses TDD (Test-Driven Development) with JUnit.
• ✅ Optimized API calls for better efficiency.

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🔗 API Integration

The API integrates with geocoding api and routes api to calculate travel duration and distance between pin codes.

🛠 API Workflow

1. First Call: API fetches data from Google Maps and stores it in the cache & database.
2. Subsequent Calls: If the same request is made, the data is retrieved from the cache/database instead of hitting Google Maps API.

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📄 API Endpoints

1. Fetch Distance & Duration

POST

🔹 Request Example:

##post
http://localhost:8080/api/calculate-distance
## json body 
{
  "originPincode": "141106",
  "destinationPincode": "110060"
}

🔹 Response Example:

{
  "from": "141106",
  "to": "110060",
  "distance": "250 km",
  "duration": "4 hours 30 minutes",
  "route": ["Route details..."]
}

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🗂 Database Structure

Table Name	Columns
distance_cache	id, from_pincode, to_pincode, distance, duration, route, created_at
pincode_info	pincode, latitude, longitude, polygon_info

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📈 Optimization Strategy

✅ Optimized API Calls Example

Call #	From Pincode	To Pincode	API Hits
1st	141106	110060	✅ Google Maps API
2nd	141106	560023	✅ Google Maps API
3rd	141106	110060	✅ Cached Response

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⚙️ Tech Stack

• Java 21
• Spring Boot (REST API)
• Google Maps API (Geocoding and Routes api)
• H2 Database (Testing) / MySQL (Production)
• JUnit (Testing)
• Postman (API Testing)

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✅ Setup & Installation

1. Clone the repository:

git clone https://github.com/your-username/Backend-Assignment.git
cd Backend-Assignment

2. Configure Google Maps API Key:
   • Go to src/main/resources/application.properties
   • Add your API key:

google.maps.api.key=YOUR_API_KEY

3. Run the application:

mvn spring-boot:run

4. Test the API using Postman
   • Use the endpoint: GET /distance?fromPincode=141106&toPincode=110060

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🔬 Testing

Run unit tests using:

mvn test

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📌 Notes

• 🔹 No UI - The API is meant for backend services and is testable via Postman.
• 🔹 Follows RESTful principles for clean and structured endpoints.
• 🔹 TDD approach - Uses JUnit to ensure robust testing.

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✨ Contributors

👤 Shekhar
📧 Contact: shekharsuman0397@gmail.com