Description
Background and motivation
#61788 added the Rate Limiting work from #52079 and while working on it we realized it made sense for rate limiters to be disposable. It started with the TokenBucket implementation which has a timer instance which should be disposed of. But it also made sense for the other rate limiters to release any pending acquisition requests from limiter.WaitAsync(..., token); as well as clean up any cancellation token registrations.
Additionally, we expect some 3rd party implementations to be backed by a network resource and async disposal is preferred in those cases.
As well as implementing the two virtual methods on the rate limiter implementations (Concurrency, TokenBucket, FixedWindow, SlidingWindow)
We went ahead and made the API disposable, filing this to make sure we properly API review it.
API Proposal
public abstract class RateLimiter
+ : IAsyncDisposable, IDisposable
{
+ protected virtual void Dispose(bool disposing) { }
+ public void Dispose() { }
+ protected virtual ValueTask DisposeAsyncCore() { }
+ public async ValueTask DisposeAsync() { }
}API Usage
var limiter = new ConcurrencyLimiter(new ConcurrencyLimiterOptions(1, QueueProcessingOrder.OldestFirst, 3));
using var lease = limiter.Acquire(1);
var task = limiter.WaitAsync(2);
await limiter.DisposeAsync();
var failedLease = await task;Alternative Designs
No response
Risks
No response