redis-cache

A Bun + TypeScript server that caches GitHub user API responses in Redis to reduce latency and avoid repeated API calls.

Features

• Endpoint: GET /user/:username
• Cache: Redis, with keys in the format cache:github:<sha256(url)>
• TTL: 30 seconds (automatic expiration, no manual refresh)
• Error Handling: Error responses (e.g., 404, 403) are not cached
• Logging: Logs each request with HIT/MISS, response time, timestamp, and URL

How It Works

1. A GET request to /user/:username is received.
2. The server checks Redis for a cached response using the key cache:github:<SHA-256 of the URL>.
3. If present (HIT): returns the cached JSON.
4. If absent (MISS): fetches from https://api.github.com/users/:username.
   • If the response is 200 OK: stores the raw JSON in Redis (TTL 30s) and returns it.
   • If the response is an error: does not cache, returns the error to the client.
5. Each request is logged, e.g.:

   [2025-05-23T10:30:00Z] MISS - /user/torvalds (312 ms)
   

Getting Started

Prerequisites

• Bun
• Redis
• Node.js (for Redis client compatibility)

Installation

bun install

Configuration

• Redis connection is handled by the redis package.
• The server listens on the port defined by the PORT environment variable or defaults to 3000.

Running the Server

bun run index.ts

Project Structure

• index.ts: Main server logic
• utils/hash.ts: SHA-256 hashing utility for cache keys
• SPECIFICATIONS.md: Project specifications and requirements

License

Private project.