public override async Task CanDequeueMultipleResourcesAtOnce()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 2,
QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
QueueLimit = 2,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
using var lease = await limiter.AcquireAsync(2);
Assert.True(lease.IsAcquired);
var wait1 = limiter.AcquireAsync(1);
var wait2 = limiter.AcquireAsync(1);
Assert.False(wait1.IsCompleted);
Assert.False(wait2.IsCompleted);
lease.Dispose();
Assert.True(limiter.TryReplenish());
var lease1 = await wait1;
var lease2 = await wait2;
Assert.True(lease1.IsAcquired);
Assert.True(lease2.IsAcquired);
}
public override async Task DisposeAsyncReleasesQueuedAcquires()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 1,
QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
QueueLimit = 3,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
var lease = limiter.AttemptAcquire(1);
var wait1 = limiter.AcquireAsync(1);
var wait2 = limiter.AcquireAsync(1);
var wait3 = limiter.AcquireAsync(1);
Assert.False(wait1.IsCompleted);
Assert.False(wait2.IsCompleted);
Assert.False(wait3.IsCompleted);
await limiter.DisposeAsync();
lease = await wait1;
Assert.False(lease.IsAcquired);
lease = await wait2;
Assert.False(lease.IsAcquired);
lease = await wait3;
Assert.False(lease.IsAcquired);
// Throws after disposal
Assert.Throws <ObjectDisposedException>(() => limiter.AttemptAcquire(1));
await Assert.ThrowsAsync <ObjectDisposedException>(() => limiter.AcquireAsync(1).AsTask());
}
public override async Task LargeAcquiresAndQueuesDoNotIntegerOverflow()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = int.MaxValue,
QueueProcessingOrder = QueueProcessingOrder.NewestFirst,
QueueLimit = int.MaxValue,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
var lease = limiter.AttemptAcquire(int.MaxValue);
Assert.True(lease.IsAcquired);
// Fill queue
var wait = limiter.AcquireAsync(3);
Assert.False(wait.IsCompleted);
var wait2 = limiter.AcquireAsync(int.MaxValue);
Assert.False(wait2.IsCompleted);
var lease1 = await wait;
Assert.False(lease1.IsAcquired);
limiter.TryReplenish();
var lease2 = await wait2;
Assert.True(lease2.IsAcquired);
}
public override async Task DropsRequestedLeaseIfPermitCountGreaterThanQueueLimitAndNoAvailability_NewestFirst()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 2,
QueueProcessingOrder = QueueProcessingOrder.NewestFirst,
QueueLimit = 1,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
var lease = limiter.AttemptAcquire(2);
Assert.True(lease.IsAcquired);
// Fill queue
var wait = limiter.AcquireAsync(1);
Assert.False(wait.IsCompleted);
var lease1 = await limiter.AcquireAsync(2);
Assert.False(lease1.IsAcquired);
limiter.TryReplenish();
lease = await wait;
Assert.True(lease.IsAcquired);
}
public override async Task QueueAvailableAfterQueueLimitHitAndResources_BecomeAvailable()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 1,
QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
QueueLimit = 1,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
var lease = limiter.AttemptAcquire(1);
var wait = limiter.AcquireAsync(1);
var failedLease = await limiter.AcquireAsync(1);
Assert.False(failedLease.IsAcquired);
limiter.TryReplenish();
lease = await wait;
Assert.True(lease.IsAcquired);
wait = limiter.AcquireAsync(1);
Assert.False(wait.IsCompleted);
limiter.TryReplenish();
lease = await wait;
Assert.True(lease.IsAcquired);
}
public override async Task CanAcquireResourcesWithAcquireAsyncWithQueuedItemsIfNewestFirst()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 2,
QueueProcessingOrder = QueueProcessingOrder.NewestFirst,
QueueLimit = 2,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
var lease = limiter.AttemptAcquire(1);
Assert.True(lease.IsAcquired);
var wait = limiter.AcquireAsync(2);
Assert.False(wait.IsCompleted);
Assert.Equal(1, limiter.GetStatistics().CurrentAvailablePermits);
lease = await limiter.AcquireAsync(1);
Assert.True(lease.IsAcquired);
Assert.False(wait.IsCompleted);
limiter.TryReplenish();
lease = await wait;
Assert.True(lease.IsAcquired);
}
public override async Task DropsMultipleOldestWhenQueuingMoreThanLimit_NewestFirst()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 2,
QueueProcessingOrder = QueueProcessingOrder.NewestFirst,
QueueLimit = 2,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
var lease = limiter.AttemptAcquire(2);
Assert.True(lease.IsAcquired);
var wait = limiter.AcquireAsync(1);
Assert.False(wait.IsCompleted);
var wait2 = limiter.AcquireAsync(1);
Assert.False(wait2.IsCompleted);
var wait3 = limiter.AcquireAsync(2);
var lease1 = await wait;
var lease2 = await wait2;
Assert.False(lease1.IsAcquired);
Assert.False(lease2.IsAcquired);
Assert.False(wait3.IsCompleted);
limiter.TryReplenish();
lease = await wait3;
Assert.True(lease.IsAcquired);
}
public override async Task CannotAcquireResourcesWithAcquireAsyncWithQueuedItemsIfOldestFirst()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 2,
QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
QueueLimit = 3,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
var lease = limiter.AttemptAcquire(1);
Assert.True(lease.IsAcquired);
var wait = limiter.AcquireAsync(2);
var wait2 = limiter.AcquireAsync(1);
Assert.False(wait.IsCompleted);
Assert.False(wait2.IsCompleted);
limiter.TryReplenish();
lease = await wait;
Assert.True(lease.IsAcquired);
Assert.False(wait2.IsCompleted);
limiter.TryReplenish();
lease = await wait2;
Assert.True(lease.IsAcquired);
}
public override async Task CancelUpdatesQueueLimit()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 1,
QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
QueueLimit = 1,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
var lease = limiter.AttemptAcquire(1);
Assert.True(lease.IsAcquired);
var cts = new CancellationTokenSource();
var wait = limiter.AcquireAsync(1, cts.Token);
cts.Cancel();
var ex = await Assert.ThrowsAsync <TaskCanceledException>(() => wait.AsTask());
Assert.Equal(cts.Token, ex.CancellationToken);
wait = limiter.AcquireAsync(1);
Assert.False(wait.IsCompleted);
limiter.TryReplenish();
lease = await wait;
Assert.True(lease.IsAcquired);
}
public override async Task CanAcquireResourceAsync_QueuesAndGrabsOldest()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 1,
QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
QueueLimit = 2,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
var lease = await limiter.AcquireAsync();
Assert.True(lease.IsAcquired);
var wait1 = limiter.AcquireAsync();
var wait2 = limiter.AcquireAsync();
Assert.False(wait1.IsCompleted);
Assert.False(wait2.IsCompleted);
lease.Dispose();
Assert.True(limiter.TryReplenish());
lease = await wait1;
Assert.True(lease.IsAcquired);
Assert.False(wait2.IsCompleted);
lease.Dispose();
Assert.Equal(0, limiter.GetStatistics().CurrentAvailablePermits);
Assert.True(limiter.TryReplenish());
lease = await wait2;
Assert.True(lease.IsAcquired);
}
public override async Task CanCancelAcquireAsyncBeforeQueuing()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 1,
QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
QueueLimit = 1,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
var lease = limiter.AttemptAcquire(1);
Assert.True(lease.IsAcquired);
var cts = new CancellationTokenSource();
cts.Cancel();
var ex = await Assert.ThrowsAsync <TaskCanceledException>(() => limiter.AcquireAsync(1, cts.Token).AsTask());
Assert.Equal(cts.Token, ex.CancellationToken);
lease.Dispose();
Assert.True(limiter.TryReplenish());
Assert.Equal(1, limiter.GetStatistics().CurrentAvailablePermits);
}
public override async Task CanDisposeAfterCancelingQueuedRequest()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 1,
QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
QueueLimit = 1,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
var lease = limiter.AttemptAcquire(1);
Assert.True(lease.IsAcquired);
var cts = new CancellationTokenSource();
var wait = limiter.AcquireAsync(1, cts.Token);
cts.Cancel();
var ex = await Assert.ThrowsAsync <TaskCanceledException>(() => wait.AsTask());
Assert.Equal(cts.Token, ex.CancellationToken);
// Make sure dispose doesn't have any side-effects when dealing with a canceled queued item
limiter.Dispose();
}
public async Task RetryMetadataOnFailedWaitAsync()
{
var options = new FixedWindowRateLimiterOptions
{
PermitLimit = 2,
QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
QueueLimit = 1,
Window = TimeSpan.FromSeconds(20),
AutoReplenishment = false
};
var limiter = new FixedWindowRateLimiter(options);
using var lease = limiter.AttemptAcquire(2);
var failedLease = await limiter.AcquireAsync(2);
Assert.False(failedLease.IsAcquired);
Assert.True(failedLease.TryGetMetadata(MetadataName.RetryAfter.Name, out var metadata));
var metaDataTime = Assert.IsType <TimeSpan>(metadata);
Assert.Equal(options.Window.Ticks, metaDataTime.Ticks);
Assert.True(failedLease.TryGetMetadata(MetadataName.RetryAfter, out var typedMetadata));
Assert.Equal(options.Window.Ticks, typedMetadata.Ticks);
Assert.Collection(failedLease.MetadataNames, item => item.Equals(MetadataName.RetryAfter.Name));
}
public override async Task GetStatisticsWithZeroPermitCount()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 100,
QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
QueueLimit = 50,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
var lease = limiter.AttemptAcquire(0);
Assert.True(lease.IsAcquired);
Assert.Equal(1, limiter.GetStatistics().TotalSuccessfulLeases);
Assert.Equal(100, limiter.GetStatistics().CurrentAvailablePermits);
lease = await limiter.AcquireAsync(0);
Assert.True(lease.IsAcquired);
Assert.Equal(2, limiter.GetStatistics().TotalSuccessfulLeases);
Assert.Equal(100, limiter.GetStatistics().CurrentAvailablePermits);
lease = limiter.AttemptAcquire(100);
Assert.True(lease.IsAcquired);
Assert.Equal(3, limiter.GetStatistics().TotalSuccessfulLeases);
Assert.Equal(0, limiter.GetStatistics().CurrentAvailablePermits);
var lease2 = limiter.AttemptAcquire(0);
Assert.False(lease2.IsAcquired);
Assert.Equal(3, limiter.GetStatistics().TotalSuccessfulLeases);
Assert.Equal(1, limiter.GetStatistics().TotalFailedLeases);
Assert.Equal(0, limiter.GetStatistics().CurrentAvailablePermits);
}
public override async Task FailsWhenQueuingMoreThanLimit_OldestFirst()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 1,
QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
QueueLimit = 1,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
using var lease = limiter.AttemptAcquire(1);
var wait = limiter.AcquireAsync(1);
var failedLease = await limiter.AcquireAsync(1);
Assert.False(failedLease.IsAcquired);
Assert.True(failedLease.TryGetMetadata(MetadataName.RetryAfter, out var timeSpan));
Assert.Equal(TimeSpan.Zero, timeSpan);
}
public override async Task CanFillQueueWithNewestFirstAfterCancelingQueuedRequestWithAnotherQueuedRequest()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 2,
QueueProcessingOrder = QueueProcessingOrder.NewestFirst,
QueueLimit = 2,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
var lease = limiter.AttemptAcquire(2);
Assert.True(lease.IsAcquired);
var cts = new CancellationTokenSource();
var wait = limiter.AcquireAsync(1, cts.Token);
// Add another item to queue, will be completed as failed later when we queue another item
var wait2 = limiter.AcquireAsync(1);
Assert.False(wait.IsCompleted);
cts.Cancel();
var ex = await Assert.ThrowsAsync <TaskCanceledException>(() => wait.AsTask());
Assert.Equal(cts.Token, ex.CancellationToken);
lease.Dispose();
var wait3 = limiter.AcquireAsync(2);
Assert.False(wait3.IsCompleted);
// will be kicked by wait3 because we're using NewestFirst
lease = await wait2;
Assert.False(lease.IsAcquired);
limiter.TryReplenish();
lease = await wait3;
Assert.True(lease.IsAcquired);
}
public override async Task ThrowsWhenWaitingForLessThanZero()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 1,
QueueProcessingOrder = QueueProcessingOrder.NewestFirst,
QueueLimit = 1,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
await Assert.ThrowsAsync <ArgumentOutOfRangeException>(async() => await limiter.AcquireAsync(-1));
}
public override async Task CanAcquireResourceAsync()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 1,
QueueProcessingOrder = QueueProcessingOrder.NewestFirst,
QueueLimit = 1,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
using var lease = await limiter.AcquireAsync();
Assert.True(lease.IsAcquired);
var wait = limiter.AcquireAsync();
Assert.False(wait.IsCompleted);
Assert.True(limiter.TryReplenish());
Assert.True((await wait).IsAcquired);
}
public override async Task AcquireAsyncZero_WithoutAvailabilityWaitsForAvailability()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 1,
QueueProcessingOrder = QueueProcessingOrder.NewestFirst,
QueueLimit = 1,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
var lease = await limiter.AcquireAsync(1);
Assert.True(lease.IsAcquired);
var wait = limiter.AcquireAsync(0);
Assert.False(wait.IsCompleted);
lease.Dispose();
Assert.True(limiter.TryReplenish());
using var lease2 = await wait;
Assert.True(lease2.IsAcquired);
}
public override async Task CanAcquireResourceAsync_QueuesAndGrabsNewest()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 2,
QueueProcessingOrder = QueueProcessingOrder.NewestFirst,
QueueLimit = 3,
Window = TimeSpan.FromMinutes(0),
AutoReplenishment = false
});
var lease = await limiter.AcquireAsync(2);
Assert.True(lease.IsAcquired);
var wait1 = limiter.AcquireAsync(2);
var wait2 = limiter.AcquireAsync();
Assert.False(wait1.IsCompleted);
Assert.False(wait2.IsCompleted);
lease.Dispose();
Assert.True(limiter.TryReplenish());
// second queued item completes first with NewestFirst
lease = await wait2;
Assert.True(lease.IsAcquired);
Assert.False(wait1.IsCompleted);
lease.Dispose();
Assert.Equal(1, limiter.GetStatistics().CurrentAvailablePermits);
Assert.True(limiter.TryReplenish());
lease = await wait1;
Assert.True(lease.IsAcquired);
}
public async Task CorrectRetryMetadataWithQueuedItem()
{
var options = new FixedWindowRateLimiterOptions
{
PermitLimit = 2,
QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
QueueLimit = 1,
Window = TimeSpan.FromSeconds(20),
AutoReplenishment = false
};
var limiter = new FixedWindowRateLimiter(options);
using var lease = limiter.AttemptAcquire(2);
// Queue item which changes the retry after time for failed items
var wait = limiter.AcquireAsync(1);
Assert.False(wait.IsCompleted);
var failedLease = await limiter.AcquireAsync(2);
Assert.False(failedLease.IsAcquired);
Assert.True(failedLease.TryGetMetadata(MetadataName.RetryAfter, out var typedMetadata));
Assert.Equal(options.Window.Ticks, typedMetadata.Ticks);
}
public override async Task AcquireAsyncZero_WithAvailability()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 1,
QueueProcessingOrder = QueueProcessingOrder.NewestFirst,
QueueLimit = 1,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
using var lease = await limiter.AcquireAsync(0);
Assert.True(lease.IsAcquired);
}
public async Task AutoReplenish_ReplenishesCounters()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 2,
QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
QueueLimit = 1,
Window = TimeSpan.FromMilliseconds(1000),
AutoReplenishment = true
});
Assert.Equal(2, limiter.GetStatistics().CurrentAvailablePermits);
limiter.AttemptAcquire(2);
var lease = await limiter.AcquireAsync(1);
Assert.True(lease.IsAcquired);
}
public async Task CorrectRetryMetadataWithNonZeroAvailableItems()
{
var options = new FixedWindowRateLimiterOptions
{
PermitLimit = 3,
QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
QueueLimit = 1,
Window = TimeSpan.FromSeconds(20),
AutoReplenishment = false
};
var limiter = new FixedWindowRateLimiter(options);
using var lease = limiter.AttemptAcquire(2);
var failedLease = await limiter.AcquireAsync(3);
Assert.False(failedLease.IsAcquired);
Assert.True(failedLease.TryGetMetadata(MetadataName.RetryAfter, out var typedMetadata));
Assert.Equal(options.Window.Ticks, typedMetadata.Ticks);
}
public override async Task GetStatisticsHasCorrectValues()
{
var limiter = new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
{
PermitLimit = 100,
QueueProcessingOrder = QueueProcessingOrder.OldestFirst,
QueueLimit = 50,
Window = TimeSpan.Zero,
AutoReplenishment = false
});
var stats = limiter.GetStatistics();
Assert.Equal(100, stats.CurrentAvailablePermits);
Assert.Equal(0, stats.CurrentQueuedCount);
Assert.Equal(0, stats.TotalFailedLeases);
Assert.Equal(0, stats.TotalSuccessfulLeases);
// success from acquire + available
var lease1 = limiter.AttemptAcquire(60);
stats = limiter.GetStatistics();
Assert.Equal(40, stats.CurrentAvailablePermits);
Assert.Equal(0, stats.CurrentQueuedCount);
Assert.Equal(0, stats.TotalFailedLeases);
Assert.Equal(1, stats.TotalSuccessfulLeases);
// queue
var lease2Task = limiter.AcquireAsync(50);
stats = limiter.GetStatistics();
Assert.Equal(40, stats.CurrentAvailablePermits);
Assert.Equal(50, stats.CurrentQueuedCount);
Assert.Equal(0, stats.TotalFailedLeases);
Assert.Equal(1, stats.TotalSuccessfulLeases);
// failure from wait
var lease3 = await limiter.AcquireAsync(1);
Assert.False(lease3.IsAcquired);
stats = limiter.GetStatistics();
Assert.Equal(40, stats.CurrentAvailablePermits);
Assert.Equal(50, stats.CurrentQueuedCount);
Assert.Equal(1, stats.TotalFailedLeases);
Assert.Equal(1, stats.TotalSuccessfulLeases);
// failure from acquire
var lease4 = limiter.AttemptAcquire(100);
Assert.False(lease4.IsAcquired);
stats = limiter.GetStatistics();
Assert.Equal(40, stats.CurrentAvailablePermits);
Assert.Equal(50, stats.CurrentQueuedCount);
Assert.Equal(2, stats.TotalFailedLeases);
Assert.Equal(1, stats.TotalSuccessfulLeases);
limiter.TryReplenish();
await lease2Task;
// success from wait + available + queue
stats = limiter.GetStatistics();
Assert.Equal(50, stats.CurrentAvailablePermits);
Assert.Equal(0, stats.CurrentQueuedCount);
Assert.Equal(2, stats.TotalFailedLeases);
Assert.Equal(2, stats.TotalSuccessfulLeases);
}