Missing caching for leaderboard API causes high database load Team: T134

[dharm2112]

Team Number : Team 134

Description

This PR adds a caching layer to the leaderboard API using a cache-aside pattern to reduce redundant database queries and improve performance.
Leaderboard data is cached with a 60-second TTL and invalidated on updates (submissions, score changes, member joins) to ensure consistency. Redis is used with an in-memory fallback for reliability.
This improves response time and scalability without introducing any breaking changes.

Related Issue

Closes #12

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Code refactoring
• Performance improvement
• Style/UI improvement

Changes Made

• Added caching layer (Redis with in-memory fallback)
• Implemented cache-aside pattern in leaderboard API
• Added TTL (60 seconds) for cached leaderboard data
• Implemented cache invalidation on:
  • new submissions
  • score updates
  • member joins
• Added centralized cache service for better maintainability
• Ensured fallback mechanism if Redis is unavailable
• Added proper error handling to prevent cache-related failures

Testing

• Tested API using Postman
• Tested on Desktop (Chrome/Firefox/Safari)
• Tested on Mobile (iOS/Android)
• Tested responsive design (different screen sizes)
• No console errors or warnings
• Code builds successfully (npm run build)

Checklist

• My code follows the project's code style guidelines
• I have performed a self-review of my code
• I have commented my code where necessary
• My changes generate no new warnings
• I have tested my changes thoroughly
• All TypeScript types are properly defined
• Tailwind CSS classes are used appropriately (no inline styles)
• Component is responsive across different screen sizes
• I have read and followed the CONTRIBUTING.md guidelines

Additional Notes

• Redis is optional; if unavailable, the system automatically falls back to in-memory caching
• No database schema changes were made
• No API response format was changed
• This is a performance optimization and does not introduce breaking changes

[krishnapaljadeja]

✅ PR Validation Passed

Hey @dharm2112! Your PR looks good. Here is what we found:

Field	Value
Team Number	Team 134
Linked Issue	Closes #12

A maintainer will review your PR within 24–48 hours. Stay responsive to feedback!

GDG CHARUSAT Open Source Contri Sprintathon