public void With_no_param_should_set_default_config()
{
var sut = new ThrottleConfiguration();
Assert.AreEqual(20, sut.MessagePerTime);
Assert.AreEqual(15, sut.IntervalInMinutes);
}
public ThrottledWorker(Throttle throttle)
{
Settings = throttle.Settings;
_throttle = throttle;
int workerThreads;
ThreadPool.GetMaxThreads(out workerThreads, out int completionPortThreads);
if (Settings.MaxConcurrentThreads != null)
{
workerThreads = Settings.MaxConcurrentThreads.Value;
}
if (workerThreads <= 0)
{
throw new ArgumentNullException($"There must be at least 1 worker thread available.");
}
_cancellationTokenSource = new CancellationTokenSource();
_queue = new BlockingCollection <TRequest>();
_workers = Enumerable.Range(0, workerThreads).Select(i => BackgroundWorker(_cancellationTokenSource.Token)).ToArray();
_throttle = new Throttle(Settings);
}
public void With_param_should_configure_throttling()
{
var sut = new ThrottleConfiguration()
{
IntervalInMinutes = 50,
MessagePerTime = 20
};
Assert.AreEqual(20, sut.MessagePerTime);
Assert.AreEqual(50, sut.IntervalInMinutes);
}
public void ThrottledWorker_CanPreventConcurrentRequests()
{
// no more than 2 concurrent threads.
ThrottleConfiguration configuration = new ThrottleConfiguration
{
MaxConcurrentThreads = 2
};
Throttle throttle = new Throttle(configuration);
ThrottledWorker throttledWorker = new ThrottledWorker(throttle);
ManualResetEvent awaiter = new ManualResetEvent(false);
CancellationTokenSource outerCancellationSource = new CancellationTokenSource(5 * 1000); // 5 seconds
const long requestCount = 5;
long success = 0;
for (int i = 0; i < requestCount; i++)
{
int instance = i;
Stopwatch sw = new Stopwatch();
sw.Start();
throttledWorker.Enqueue(async() => {
CancellationTokenSource innerCancellationSource = CancellationTokenSource.CreateLinkedTokenSource(
outerCancellationSource.Token,
new CancellationTokenSource(5 * 1000).Token // 5 seconds
);
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Request {instance}: acquired lease (waitTime: {sw.Elapsed})");
sw.Restart();
awaiter.WaitOne();
await Task.Delay(1000, innerCancellationSource.Token); // do some work
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Request {instance}: completed work (runTime: {sw.Elapsed})");
Assert.True(throttle.ActiveThreads <= configuration.MaxConcurrentThreads, $"Instance {instance}: Thread count exceeds max concurrent threads (actual: {throttle.ActiveThreads}, max: {configuration.MaxConcurrentThreads})");
long current = Interlocked.Increment(ref success);
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Request {instance}: thread complete (runTime: {sw.Elapsed}, success: {current})");
});
}
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] set.....");
awaiter.Set();
throttledWorker.Wait(outerCancellationSource.Token);
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] complete.....");
long actual = Interlocked.Read(ref success);
Assert.Equal(requestCount, actual);
}
public void Throttle_CanWaitBetweenRequests_FromEndOfLastRequest()
{
// no more than 1 thread per second from end of last request
ThrottleConfiguration configuration = new ThrottleConfiguration
{
WaitTimeBetweenLease = TimeSpan.FromSeconds(1),
WaitStrategy = ThrottleWaitStrategy.FromEndOfLastRequest
};
Throttle throttle = new Throttle(configuration);
Task[] threads = new Task[5];
ManualResetEvent awaiter = new ManualResetEvent(false);
for (int i = 0; i < threads.Length; i++)
{
int instance = i;
threads[i] = Task.Run(() => {
awaiter.WaitOne();
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: thread started");
using (throttle.AcquireLease())
{
TimeSpan?timeSinceLastRequest = DateTimeOffset.Now - throttle.LastFinishTime;
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: aquired lease (threads: {throttle.ActiveThreads}, timeSinceLastRequest: {timeSinceLastRequest})");
Assert.True(throttle.ActiveThreads <= configuration.MaxConcurrentThreads, $"Instance {instance}: Thread count exceeds max concurrent threads (actual: {throttle.ActiveThreads}, max: {configuration.MaxConcurrentThreads})");
if (timeSinceLastRequest != null)
{
Assert.True(timeSinceLastRequest >= configuration.WaitTimeBetweenLease, $"Instance {instance}: Wait time exceeds min wait time (actual: {timeSinceLastRequest}, min: {configuration.WaitTimeBetweenLease})");
}
Thread.Sleep(1000); // do some work
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: completed work");
}
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: released lease (threads: {throttle.ActiveThreads})");
});
}
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] set.....");
awaiter.Set();
Task.WaitAll(threads);
}
public void Throttle_CanWaitBetweenRequests_TumblingWindow()
{
// No more than 2 requests per 5 seconds and only 1 concurrent thread.
ThrottleConfiguration configuration = new ThrottleConfiguration
{
WaitTimeBetweenLease = TimeSpan.FromSeconds(5),
WaitStrategy = ThrottleWaitStrategy.TumblingWindow,
MaxConcurrentThreads = 1,
MaxRequests = 2
};
Throttle throttle = new Throttle(configuration);
Task[] threads = new Task[5];
ManualResetEvent awaiter = new ManualResetEvent(false);
for (int i = 0; i < threads.Length; i++)
{
int instance = i;
threads[i] = Task.Run(() => {
awaiter.WaitOne();
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: thread started");
using (throttle.AcquireLease())
{
TimeSpan?timeSinceLastRequest = DateTimeOffset.Now - throttle.LastFinishTime;
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: acquired lease (window: {throttle.RateWindow?.DateTime:yyyy-MM-dd HH:mm:ss.fff}, threads: {throttle.ActiveThreads}, requests: {throttle.RequestCount})");
Assert.True(throttle.ActiveThreads <= configuration.MaxConcurrentThreads, $"Instance {instance}: Thread count exceeds max concurrent threads (actual: {throttle.ActiveThreads}, max: {configuration.MaxConcurrentThreads})");
Assert.True(throttle.RequestCount <= configuration.MaxRequests, $"Instance {instance}: Request count exceeds max request count (actual: {throttle.RequestCount}, max: {configuration.MaxRequests})");
Thread.Sleep(1000); // do some work
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: completed work");
}
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: released lease (threads: {throttle.ActiveThreads})");
});
}
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] set.....");
awaiter.Set();
Task.WaitAll(threads);
}
public void ThrottledWorker_CanWaitBetweenRequests_SlidingWindow()
{
// no more than 2 request per 1 second
ThrottleConfiguration configuration = new ThrottleConfiguration
{
WaitTimeBetweenLease = TimeSpan.FromSeconds(1),
WaitStrategy = ThrottleWaitStrategy.SlidingWindow,
MaxRequests = 2,
//RecursionStrategy = ThrottleRecursionStrategy.AllowsRecursion
};
Throttle throttle = new Throttle(configuration);
ThrottledWorker throttledWorker = new ThrottledWorker(throttle);
const int requestCount = 10;
ManualResetEvent awaiter = new ManualResetEvent(false);
for (int i = 0; i < requestCount; i++)
{
int instance = i;
throttledWorker.Enqueue(() => {
awaiter.WaitOne();
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: thread started");
//using (throttle.AcquireLease())
{
TimeSpan?timeSinceLastRequest = DateTimeOffset.Now - throttle.LastFinishTime;
Assert.True(throttle.ActiveThreads <= configuration.MaxConcurrentThreads, $"Instance {instance}: Thread count exceeds max concurrent threads (actual: {throttle.ActiveThreads}, max: {configuration.MaxConcurrentThreads})");
Assert.True(throttle.RequestCount <= configuration.MaxRequests, $"Instance {instance}: Request count exceeds max request count (actual: {throttle.RequestCount}, max: {configuration.MaxRequests})");
Thread.Sleep(1000); // do some work
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: completed work");
}
});
}
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] set.....");
awaiter.Set();
throttledWorker.Wait();
}
public void ThrottledWorker_CanWaitBetweenRequests_FromStartOfLastRequest()
{
// no more than 1 thread per second from start of last request.
ThrottleConfiguration configuration = new ThrottleConfiguration
{
WaitTimeBetweenLease = TimeSpan.FromSeconds(1),
WaitStrategy = ThrottleWaitStrategy.FromStartOfLastRequest
};
Throttle throttle = new Throttle(configuration);
ThrottledWorker throttledWorker = new ThrottledWorker(throttle);
const int requestCount = 5;
ManualResetEvent awaiter = new ManualResetEvent(false);
CancellationTokenSource outerCancellationSource = new CancellationTokenSource(12 * 1000); // 12 seconds
DateTimeOffset?lastRequestTime = null;
object _lock = new object();
long success = 0;
for (int i = 0; i < requestCount; i++)
{
int instance = i;
Stopwatch sw = new Stopwatch();
sw.Start();
throttledWorker.Enqueue(() =>
{
awaiter.WaitOne();
TimeSpan?timeSinceLastRequest;
lock (_lock)
{
timeSinceLastRequest = DateTimeOffset.Now - lastRequestTime;
if (lastRequestTime == null || throttle.LastRequestTime > lastRequestTime)
{
lastRequestTime = throttle.LastRequestTime;
}
}
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: aquired lease (threads: {throttle.ActiveThreads}, timeSinceLastRequest: {timeSinceLastRequest})");
Assert.True(throttle.ActiveThreads <= configuration.MaxConcurrentThreads, $"Instance {instance}: Thread count exceeds max concurrent threads (actual: {throttle.ActiveThreads}, max: {configuration.MaxConcurrentThreads})");
if (timeSinceLastRequest != null)
{
Assert.True(timeSinceLastRequest >= configuration.WaitTimeBetweenLease, $"Instance {instance}: Wait time exceeds min wait time (actual: {timeSinceLastRequest}, min: {configuration.WaitTimeBetweenLease})");
}
Thread.Sleep(1000); // do some work
long current = Interlocked.Increment(ref success);
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: completed work");
});
}
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] set.....");
awaiter.Set();
throttledWorker.Wait();
long actual = Interlocked.Read(ref success);
Assert.Equal(requestCount, actual);
}
public Throttle(ThrottleConfiguration configuration)
{
Settings = configuration;
if (configuration.MaxRequests != null)
{
if (configuration.WaitStrategy == null)
{
throw new ArgumentNullException($"{nameof(configuration.WaitStrategy)} is required when {nameof(configuration.MaxRequests)} is specified.");
}
if (configuration.WaitTimeBetweenLease == null)
{
throw new ArgumentNullException($"{nameof(configuration.WaitTimeBetweenLease)} is required when {nameof(configuration.MaxRequests)} is specified.");
}
if (configuration.MaxRequests <= 0)
{
throw new ArgumentOutOfRangeException($"{nameof(configuration.MaxRequests)} must be greater than 0.");
}
if (configuration.MaxConcurrentThreads == null)
{
configuration.MaxConcurrentThreads = configuration.MaxRequests;
}
if (configuration.MaxConcurrentThreads > configuration.MaxRequests)
{
throw new ArgumentOutOfRangeException($"{nameof(configuration.MaxConcurrentThreads)} must be less than or equal to {nameof(configuration.MaxRequests)}.");
}
}
if (configuration.WaitTimeBetweenLease != null || configuration.WaitStrategy != null)
{
if (configuration.WaitStrategy == null)
{
throw new ArgumentNullException($"{nameof(configuration.WaitStrategy)} is required when {nameof(configuration.WaitTimeBetweenLease)} is specified.");
}
if (configuration.WaitTimeBetweenLease == null)
{
throw new ArgumentNullException($"{nameof(configuration.WaitTimeBetweenLease)} is required when {nameof(configuration.WaitStrategy)} is specified.");
}
if (configuration.WaitTimeBetweenLease <= TimeSpan.Zero)
{
throw new ArgumentOutOfRangeException($"{nameof(configuration.WaitTimeBetweenLease)} must be greater than 0.");
}
switch (configuration.WaitStrategy)
{
case ThrottleWaitStrategy.FromEndOfLastRequest:
case ThrottleWaitStrategy.FromStartOfLastRequest:
configuration.MaxRequests = 1;
configuration.MaxConcurrentThreads = 1;
break;
case ThrottleWaitStrategy.SlidingWindow:
case ThrottleWaitStrategy.TumblingWindow:
if (configuration.MaxRequests == null)
{
throw new ArgumentNullException($"{nameof(configuration.MaxRequests)} is required when {nameof(configuration.WaitStrategy)} is {configuration.WaitStrategy}.");
}
_requests = new List <long>();
break;
}
}
if (configuration.MaxConcurrentThreads != null)
{
if (configuration.MaxConcurrentThreads <= 0)
{
throw new ArgumentOutOfRangeException($"{nameof(configuration.MaxConcurrentThreads)} must be greater than 0.");
}
_semaphore = new SemaphoreSlim(configuration.MaxConcurrentThreads.Value, configuration.MaxConcurrentThreads.Value);
}
}
public ThrottledWorker(ThrottleConfiguration configuration)
: this(new Throttle(configuration))
{
}
public void Throttle_CanPreventConcurrentRequests()
{
// no more than 2 concurrent threads.
ThrottleConfiguration configuration = new ThrottleConfiguration
{
MaxConcurrentThreads = 2
};
Throttle throttle = new Throttle(configuration);
Task[] threads = new Task[5];
ManualResetEvent awaiter = new ManualResetEvent(false);
CancellationTokenSource outerCancellationSource = new CancellationTokenSource(5 * 1000); // 5 seconds
long success = 0;
for (int i = 0; i < threads.Length; i++)
{
int instance = i;
Stopwatch sw = new Stopwatch();
sw.Start();
threads[i] = Task.Run(async() => {
CancellationTokenSource innerCancellationSource = CancellationTokenSource.CreateLinkedTokenSource(
outerCancellationSource.Token,
new CancellationTokenSource(5 * 1000).Token // 5 seconds
);
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: thread activated (activateTime: {sw.Elapsed})");
sw.Restart();
awaiter.WaitOne();
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: thread started (runTime: {sw.Elapsed})");
try
{
IDisposable lease = await throttle.AcquireLeaseAsync(innerCancellationSource.Token);
using (lease)
{
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: acquired lease (threads: {throttle.ActiveThreads}, runTime: {sw.Elapsed})");
await Task.Delay(1000, innerCancellationSource.Token); // do some work
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: completed work (runTime: {sw.Elapsed})");
Assert.True(throttle.ActiveThreads <= configuration.MaxConcurrentThreads, $"Instance {instance}: Thread count exceeds max concurrent threads (actual: {throttle.ActiveThreads}, max: {configuration.MaxConcurrentThreads})");
}
long current = Interlocked.Increment(ref success);
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: thread complete (runTime: {sw.Elapsed}, success: {current})");
}
catch (Exception ex)
{
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] Instance {instance}: thread failed (runTime: {sw.Elapsed}) {ex}");
throw new Exception("Operation failed", ex);
}
});
}
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] set.....");
awaiter.Set();
Task.WaitAll(threads, outerCancellationSource.Token);
Log.WriteLine($"[{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff}] complete.....");
long actual = Interlocked.Read(ref success);
Assert.Equal(threads.Length, actual);
}