A fast, simple, and small Generic Cell Rate (GCR) algorithm implementation with zero dependencies that allows for dynamic rate adjustment.
use gcr::Gcr; let mut rate = Gcr::new(10, Duration::from_secs(1), Some(30)).unwrap(); // 10 units allowed every second with a max burst of 30 units at once rate.request(20).unwrap(); // Leftover capacity is now 10 rate.request(20).unwrap_err(); // Returns `DeniedFor(1 second)`[Gcr::adjust] can be used to change the rate of the limiter while preserving the current capacity.
It accepts the same parameters as [Gcr::new].
rate.adjust(20, Duration::from_secs(1), Some(30)).unwrap(); // 20 units allowed every second with a max burst of 30 units at once[Gcr::capacity] can be used to get the current capacity of the rate limiter without making a request.
rate.capacity();