Implement Rate Limiting Middleware for PDF Generator API #19
Description
Implement rate limiting middleware on the /pdf/generate API endpoint to prevent abuse, ensure fair usage, and protect server resources.
Details
- Apply rate limits based on user identity (user ID extracted from JWT) or IP address if the user is unauthenticated.
Suggested Default Limits
- Max 20 requests per minute per user/IP.
- Configurable limits via environment variables for flexibility.
- Use a scalable rate limiting library compatible with the backend stack
(e.g.,express-rate-limit, Redis-backed limiter). - Return HTTP 429 Too Many Requests status with a clear message when limits are exceeded.
- Log rate limit violations with relevant metadata (user ID, IP, timestamp).
- Ensure the middleware gracefully handles edge cases (e.g., missing user info).
- Write automated tests simulating burst requests to verify limit enforcement and correct responses.
Acceptance Criteria
- Rate limiting middleware correctly restricts excessive requests per user/IP.
- Clients exceeding limits receive 429 responses with meaningful messages.
- Rate limit breach events are logged for monitoring.
- Tests cover normal usage and limit breach scenarios.