Spring Boot REST API: Managing Rate Limiting with Redis and Handling 429 Responses
Quick question that's been bugging me - Quick question that's been bugging me - I'm building a feature where I'm working on a personal project and I'm building a Spring Boot REST API that needs to enforce rate limiting per user to prevent abuse..... I'm using Redis to store the rate limit counters, but I'm encountering issues when users exceed their allowed requests. Specifically, I want to return a 429 Too Many Requests response when the limit is hit, but I'm not sure how to implement this cleanly. My current implementation looks like this: ```java @RestController @RequestMapping("/api") public class MyController { @Autowired private RedisTemplate<String, Integer> redisTemplate; @GetMapping("/resource") public ResponseEntity<String> getResource(@RequestParam String userId) { Integer requestCount = redisTemplate.opsForValue().get(userId); if (requestCount != null && requestCount >= 5) { return ResponseEntity.status(HttpStatus.TOO_MANY_REQUESTS) .body("Rate limit exceeded"); } redisTemplate.opsForValue().increment(userId); return ResponseEntity.ok("Resource data"); } } ``` I've tried adjusting the Redis TTL to reset the count after a minute, but I still get a lot of 200 OK responses even when the limit is exceeded. I'm not sure if I'm checking the request count correctly or if I need to modify my Redis configuration. The version of Spring Boot I'm using is 2.5.4. Additionally, if a user hits the limit, I want to ensure that no further processing occurs in that request, but it seems the response is still being sent as 200 OK under certain conditions. Is there a more effective way to handle this scenario? Any insights or examples would be greatly appreciated! For context: I'm using Java on Linux. Has anyone else encountered this? My development environment is Debian. Thanks in advance! I'm using Java stable in this project. I appreciate any insights!