ratelimiter

A convenient Spring library that allows you to limit the rate at which annotated methods are called. Based on Guava's RateLimiter class.

Example

First, add this spring starter to your project's classpath. Then configure a key with a rate limit (given in permits per second or queries per second as its sometimes called) in your configuration file. The example below configures the demo-group key to a limit of 10 permits per second.

tarsiswt.ratelimiter.configuration.demo-group.qps=1

Finally add the @Limited annotation to the methods you wish apply the rate limit with the given key:

@SpringBootApplication
public class DemoApplication {
    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }
}

@Component
class MyRateLimitedComponent {
    @Limited(key = "demo-group")
    public void rateLimitedMethod() {
    }
}

Calls made to the rateLimitedMethod will now be subjected to the configured rate limit for its key (demo-group) in this case.

How it works

An @Aspect (especifically RateLimiterAspect) will intercept calls to methods annotated with @Limited and lookup is corresponding rate limit configuration. Currently there is only one implementation for the Limiter interface and that is the GuavaBasedLimiter which is essencially a wraper for Guava's RateLimiter and so the rate limiting works exactly as described in its Javadoc.