Struct RateLimiter 

pub struct RateLimiter { /* private fields */ }

An async token-bucket rate limiter that throttles aggregate transfer throughput.

Construct with RateLimiter::new. When max_bytes_per_sec is None (or Some(0)), the limiter is unlimited and acquire returns immediately. Otherwise tokens refill at max_bytes_per_sec per second, allowing a burst of up to ~1 second’s worth of budget.

The limiter is Arc-shareable and Clone (cloning shares the same underlying bucket).

Implementations

impl RateLimiter

pub fn new(max_bytes_per_sec: Option<u64>) -> Self

Builds a limiter. None (or Some(0)) yields an unlimited, no-op limiter whose acquire never waits.

pub async fn set_rate(&self, bytes_per_sec: Option<u64>)

Retunes the limiter’s aggregate byte-rate cap live, so an adaptive controller can raise or lower throttling between operations.

• None (or Some(0)) switches the limiter to unlimited: the rate and capacity drop to 0 and the bucket is emptied, so the next acquire is a no-op.
• Some(r > 0) installs (or replaces) a bucket refilling at r bytes/sec with ~1 second of burst capacity. Switching from unlimited to limited primes the bucket full (tokens = capacity) so a freshly throttled limiter still allows one immediate burst.

Calling set_rate is the only way the rate changes after [new]; limiters that never call it behave exactly as before.

pub async fn acquire(&self, n: u64)

Blocks until n bytes of budget are available, refilling the bucket at the configured rate. Unlimited limiters return immediately.

A single request larger than the bucket capacity is still satisfied: the bucket is allowed to go negative and the caller waits out the deficit, so throttling is correct even for objects bigger than one second’s worth of budget.

Trait Implementations

impl Clone for RateLimiter

fn clone(&self) -> RateLimiter

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for RateLimiter

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.