public static void BasicHttp_Abort_ChannelFactory_Operations_Active()
{
// Test creates 2 channels from a single channel factory and
// aborts the channel factory while both channels are executing
// operations. This verifies the operations are cancelled and
// the channel factory is in the correct state.
BasicHttpBinding binding = null;
TimeSpan delayOperation = TimeSpan.FromSeconds(3);
ChannelFactory <IWcfService> factory = null;
IWcfService serviceProxy1 = null;
IWcfService serviceProxy2 = null;
try
{
// *** SETUP *** \\
binding = new BasicHttpBinding(BasicHttpSecurityMode.None);
binding.CloseTimeout = ScenarioTestHelpers.TestTimeout;
factory = new ChannelFactory <IWcfService>(binding, new EndpointAddress(Endpoints.HttpBaseAddress_Basic));
serviceProxy1 = factory.CreateChannel();
serviceProxy2 = factory.CreateChannel();
// *** EXECUTE *** \\
Task <string> t1 = serviceProxy1.EchoWithTimeoutAsync("first", delayOperation);
Task <string> t2 = serviceProxy2.EchoWithTimeoutAsync("second", delayOperation);
factory.Abort();
// *** VALIDATE *** \\
Assert.True(factory.State == CommunicationState.Closed,
String.Format("Expected factory state 'Closed', actual was '{0}'", factory.State));
Assert.Throws <TaskCanceledException>(() => t1.GetAwaiter().GetResult());
Assert.Throws <TaskCanceledException>(() => t2.GetAwaiter().GetResult());
Assert.True(((ICommunicationObject)serviceProxy1).State == CommunicationState.Closed,
String.Format("Expected channel 1 state 'Closed', actual was '{0}'", ((ICommunicationObject)serviceProxy1).State));
Assert.True(((ICommunicationObject)serviceProxy2).State == CommunicationState.Closed,
String.Format("Expected channel 2 state 'Closed', actual was '{0}'", ((ICommunicationObject)serviceProxy2).State));
// *** CLEANUP *** \\
((ICommunicationObject)serviceProxy1).Abort();
((ICommunicationObject)serviceProxy2).Abort();
}
finally
{
// *** ENSURE CLEANUP *** \\
ScenarioTestHelpers.CloseCommunicationObjects((ICommunicationObject)serviceProxy1,
(ICommunicationObject)serviceProxy2,
factory);
}
}
public static void BasicHttp_Async_Close_ChannelFactory_Operations_Active()
{
// Test creates 2 channels from a single channel factory and
// asynchronously closes the channel factory while both channels are
// executing operations. This verifies the operations are cancelled and
// the channel factory is in the correct state.
BasicHttpBinding binding = null;
TimeSpan delayOperation = TimeSpan.FromSeconds(3);
ChannelFactory <IWcfService> factory = null;
IWcfService serviceProxy1 = null;
IWcfService serviceProxy2 = null;
string expectedEcho1 = "first";
string expectedEcho2 = "second";
try
{
// *** SETUP *** \\
binding = new BasicHttpBinding(BasicHttpSecurityMode.None);
binding.CloseTimeout = ScenarioTestHelpers.TestTimeout;
binding.SendTimeout = ScenarioTestHelpers.TestTimeout;
factory = new ChannelFactory <IWcfService>(binding, new EndpointAddress(Endpoints.HttpBaseAddress_Basic));
serviceProxy1 = factory.CreateChannel();
serviceProxy2 = factory.CreateChannel();
// *** EXECUTE *** \\
Task <string> t1 = serviceProxy1.EchoWithTimeoutAsync(expectedEcho1, delayOperation);
Task <string> t2 = serviceProxy2.EchoWithTimeoutAsync(expectedEcho2, delayOperation);
Task factoryTask = Task.Factory.FromAsync(factory.BeginClose, factory.EndClose, TaskCreationOptions.None);
// *** VALIDATE *** \\
factoryTask.GetAwaiter().GetResult();
Assert.True(factory.State == CommunicationState.Closed,
String.Format("Expected factory state 'Closed', actual was '{0}'", factory.State));
Exception exception1 = null;
Exception exception2 = null;
string actualEcho1 = null;
string actualEcho2 = null;
// Verification is slightly more complex for the close with active operations because
// we don't know which might have completed first and whether the channel factory
// was able to close and dispose either channel before it completed. So we just
// ensure the Tasks complete with an exception or a successful return and have
// been closed by the factory.
try
{
actualEcho1 = t1.GetAwaiter().GetResult();
}
catch (Exception e)
{
exception1 = e;
}
try
{
actualEcho2 = t2.GetAwaiter().GetResult();
}
catch (Exception e)
{
exception2 = e;
}
Assert.True(exception1 != null || actualEcho1 != null, "First operation should have thrown Exception or returned an echo");
Assert.True(exception2 != null || actualEcho2 != null, "Second operation should have thrown Exception or returned an echo");
Assert.True(actualEcho1 == null || String.Equals(expectedEcho1, actualEcho1),
String.Format("First operation returned '{0}' but expected '{1}'.", expectedEcho1, actualEcho1));
Assert.True(actualEcho2 == null || String.Equals(expectedEcho2, actualEcho2),
String.Format("Second operation returned '{0}' but expected '{1}'.", expectedEcho2, actualEcho2));
Assert.True(((ICommunicationObject)serviceProxy1).State == CommunicationState.Closed,
String.Format("Expected channel 1 state 'Closed', actual was '{0}'", ((ICommunicationObject)serviceProxy1).State));
Assert.True(((ICommunicationObject)serviceProxy2).State == CommunicationState.Closed,
String.Format("Expected channel 2 state 'Closed', actual was '{0}'", ((ICommunicationObject)serviceProxy2).State));
// *** CLEANUP *** \\
((ICommunicationObject)serviceProxy1).Abort();
((ICommunicationObject)serviceProxy2).Abort();
}
finally
{
// *** ENSURE CLEANUP *** \\
ScenarioTestHelpers.CloseCommunicationObjects((ICommunicationObject)serviceProxy1,
(ICommunicationObject)serviceProxy2,
factory);
}
}
public static void Abort_During_Implicit_Open_Closes_Async_Waiters()
{
// This test is a regression test of an issue with CallOnceManager.
// When a single proxy is used to make several service calls without
// explicitly opening it, the CallOnceManager queues up all the requests
// that happen while it is opening the channel (or handling previously
// queued service calls. If the channel was closed or faulted during
// the handling of any queued requests, it caused a pathological worst
// case where every queued request waited for its complete SendTimeout
// before failing.
//
// This test operates by making multiple concurrent asynchronous service
// calls, but stalls the Opening event to allow them to be queued before
// any of them are allowed to proceed. It then closes the channel when
// the first service operation is allowed to proceed. This causes the
// CallOnce manager to deal with all its queued operations and cause
// them to complete other than by timing out.
BasicHttpBinding binding = null;
ChannelFactory <IWcfService> factory = null;
IWcfService serviceProxy = null;
int timeoutMs = 20000;
long operationsQueued = 0;
int operationCount = 5;
Task <string>[] tasks = new Task <string> [operationCount];
Exception[] exceptions = new Exception[operationCount];
string[] results = new string[operationCount];
bool isClosed = false;
DateTime endOfOpeningStall = DateTime.Now;
int serverDelayMs = 100;
TimeSpan serverDelayTimeSpan = TimeSpan.FromMilliseconds(serverDelayMs);
string testMessage = "testMessage";
try
{
// *** SETUP *** \\
binding = new BasicHttpBinding(BasicHttpSecurityMode.None);
binding.TransferMode = TransferMode.Streamed;
// SendTimeout is the timeout used for implicit opens
binding.SendTimeout = TimeSpan.FromMilliseconds(timeoutMs);
factory = new ChannelFactory <IWcfService>(binding, new EndpointAddress(Endpoints.HttpBaseAddress_Basic_Text));
serviceProxy = factory.CreateChannel();
// Force the implicit open to stall until we have multiple concurrent calls pending.
// This forces the CallOnceManager to have a queue of waiters it will need to notify.
((ICommunicationObject)serviceProxy).Opening += (s, e) =>
{
// Wait until we see sync calls have been queued
DateTime startOfOpeningStall = DateTime.Now;
while (true)
{
endOfOpeningStall = DateTime.Now;
// Don't wait forever -- if we stall longer than the SendTimeout, it means something
// is wrong other than what we are testing, so just fail early.
if ((endOfOpeningStall - startOfOpeningStall).TotalMilliseconds > timeoutMs)
{
Assert.True(false, "The Opening event timed out waiting for operations to queue, which was not expected for this test.");
}
// As soon as we have all our Tasks at least running, wait a little
// longer to allow them finish queuing up their waiters, then stop stalling the Opening
if (Interlocked.Read(ref operationsQueued) >= operationCount)
{
Task.Delay(500).Wait();
endOfOpeningStall = DateTime.Now;
return;
}
Task.Delay(100).Wait();
}
};
// Each task will make a synchronous service call, which will cause all but the
// first to be queued for the implicit open. The first call to complete then closes
// the channel so that it is forced to deal with queued waiters.
Func <string> callFunc = () =>
{
// We increment the # ops queued before making the actual sync call, which is
// technically a short race condition in the test. But reversing the order would
// timeout the implicit open and fault the channel.
Interlocked.Increment(ref operationsQueued);
// The call of the operation is what creates the entry in the CallOnceManager queue.
// So as each Task below starts, it increments the count and adds a waiter to the
// queue. We ask for a small delay on the server side just to introduce a small
// stall after the sync request has been made before it can complete. Otherwise
// fast machines can finish all the requests before the first one finishes the Close().
Task <string> t = serviceProxy.EchoWithTimeoutAsync(testMessage, serverDelayTimeSpan);
lock (tasks)
{
if (!isClosed)
{
try
{
isClosed = true;
((ICommunicationObject)serviceProxy).Abort();
}
catch { }
}
}
return(t.GetAwaiter().GetResult());
};
// *** EXECUTE *** \\
DateTime startTime = DateTime.Now;
for (int i = 0; i < operationCount; ++i)
{
tasks[i] = Task.Run(callFunc);
}
for (int i = 0; i < operationCount; ++i)
{
try
{
results[i] = tasks[i].GetAwaiter().GetResult();
}
catch (Exception ex)
{
exceptions[i] = ex;
}
}
// *** VALIDATE *** \\
double elapsedMs = (DateTime.Now - endOfOpeningStall).TotalMilliseconds;
// Before validating that the issue was fixed, first validate that we received the exceptions or the
// results we expected. This is to verify the fix did not introduce a behavioral change other than the
// elimination of the long unnecessary timeouts after the channel was closed.
int nFailures = 0;
for (int i = 0; i < operationCount; ++i)
{
if (exceptions[i] == null)
{
Assert.True((String.Equals("test", results[i])),
String.Format("Expected operation #{0} to return '{1}' but actual was '{2}'",
i, testMessage, results[i]));
}
else
{
++nFailures;
TimeoutException toe = exceptions[i] as TimeoutException;
Assert.True(toe == null, String.Format("Task [{0}] should not have failed with TimeoutException", i));
}
}
Assert.True(nFailures > 0,
String.Format("Expected at least one operation to throw an exception, but none did. Elapsed time = {0} ms.",
elapsedMs));
// --- Here is the test of the actual bug fix ---
// The original issue was that sync waiters in the CallOnceManager were not notified when
// the channel became unusable and therefore continued to time out for the full amount.
// Additionally, because they were executed sequentially, it was also possible for each one
// to time out for the full amount. Given that we closed the channel, we expect all the queued
// waiters to have been immediately waked up and detected failure.
int expectedElapsedMs = (operationCount * serverDelayMs) + timeoutMs / 2;
Assert.True(elapsedMs < expectedElapsedMs,
String.Format("The {0} operations took {1} ms to complete which exceeds the expected {2} ms",
operationCount, elapsedMs, expectedElapsedMs));
// *** CLEANUP *** \\
((ICommunicationObject)serviceProxy).Close();
factory.Close();
}
finally
{
// *** ENSURE CLEANUP *** \\
ScenarioTestHelpers.CloseCommunicationObjects((ICommunicationObject)serviceProxy, factory);
}
}
