public async Task EventQueueTimeout()
{
using (StartLog(out var loggerFactory))
{
var logger = loggerFactory.CreateLogger <HttpConnectionTests>();
var testTransport = new TestTransport();
await WithConnectionAsync(
CreateConnection(transport : testTransport),
async (connection, closed) =>
{
var onReceived = new SyncPoint();
connection.OnReceived(_ => onReceived.WaitToContinue().OrTimeout());
logger.LogInformation("Starting connection");
await connection.StartAsync(TransferFormat.Text).OrTimeout();
logger.LogInformation("Started connection");
await testTransport.Application.Output.WriteAsync(new byte[] { 1 });
await onReceived.WaitForSyncPoint().OrTimeout();
// Dispose should complete, even though the receive callbacks are completely blocked up.
logger.LogInformation("Disposing connection");
await connection.DisposeAsync().OrTimeout(TimeSpan.FromSeconds(10));
logger.LogInformation("Disposed connection");
// Clear up blocked tasks.
onReceived.Continue();
});
}
}
/// <summary>
/// Creates a re-entrant function that waits for sync points in sequence.
/// </summary>
/// <param name="count">The number of sync points to expect</param>
/// <param name="syncPoints">The <see cref="SyncPoint"/> objects that can be used to coordinate the sync point</param>
/// <returns></returns>
public static Func <Task> Create(int count, out SyncPoint[] syncPoints)
{
// Need to use a local so the closure can capture it. You can't use out vars in a closure.
var localSyncPoints = new SyncPoint[count];
for (var i = 0; i < count; i += 1)
{
localSyncPoints[i] = new SyncPoint();
}
syncPoints = localSyncPoints;
var counter = 0;
return(() =>
{
if (counter >= localSyncPoints.Length)
{
return Task.CompletedTask;
}
else
{
var syncPoint = localSyncPoints[counter];
counter += 1;
return syncPoint.WaitToContinue();
}
});
}
public static Func <Task> Create(out SyncPoint syncPoint)
{
var handler = Create(1, out var syncPoints);
syncPoint = syncPoints[0];
return(handler);
}
public async Task CanCancelStartingConnectionAfterNegotiate()
{
using (StartVerifiableLog())
{
// Set up a SyncPoint within Negotiate, so we can verify
// that the call has gotten that far
var negotiateSyncPoint = new SyncPoint();
var testHttpHandler = new TestHttpMessageHandler(autoNegotiate: false);
testHttpHandler.OnNegotiate(async(request, cancellationToken) =>
{
// Wait here for the test code to cancel the "outer" token
await negotiateSyncPoint.WaitToContinue().OrTimeout();
// Cancel
cancellationToken.ThrowIfCancellationRequested();
return(ResponseUtils.CreateResponse(HttpStatusCode.OK));
});
await WithConnectionAsync(
CreateConnection(testHttpHandler),
async (connection) =>
{
// Kick off StartAsync, but don't wait for it
var cts = new CancellationTokenSource();
var startTask = connection.StartAsync(cts.Token);
// Wait for the connection to get to the "WaitToContinue" call above,
// which means it has gotten to Negotiate
await negotiateSyncPoint.WaitForSyncPoint().OrTimeout();
// Assert that StartAsync has not yet been canceled
Assert.False(startTask.IsCanceled);
// Cancel StartAsync, then "release" the SyncPoint
// so the negotiate handler can keep going
cts.Cancel();
negotiateSyncPoint.Continue();
// Assert that StartAsync was canceled
await Assert.ThrowsAsync <OperationCanceledException>(() => startTask).OrTimeout();
});
}
}
public async Task EventsAreNotRunningOnMainLoop()
{
var testTransport = new TestTransport();
await WithConnectionAsync(
CreateConnection(transport : testTransport),
async (connection, closed) =>
{
// Block up the OnReceived callback until we finish the test.
var onReceived = new SyncPoint();
connection.OnReceived(_ => onReceived.WaitToContinue().OrTimeout());
await connection.StartAsync().OrTimeout();
// This will trigger the received callback
await testTransport.Application.Output.WriteAsync(new byte[] { 1 });
// Wait to hit the sync point. We are now blocking up the TaskQueue
await onReceived.WaitForSyncPoint().OrTimeout();
// Now we write something else and we want to test that the HttpConnection receive loop is still
// removing items from the channel even though OnReceived is blocked up.
await testTransport.Application.Output.WriteAsync(new byte[] { 1 });
// Now that we've written, we wait for WaitToReadAsync to return an INCOMPLETE task. It will do so
// once HttpConnection reads the message. We also use a CTS to timeout in case the loop is indeed blocked
var cts = new CancellationTokenSource();
cts.CancelAfter(TimeSpan.FromSeconds(5));
while (testTransport.Application.Input.WaitToReadAsync().IsCompleted&& !cts.IsCancellationRequested)
{
// Yield to allow the HttpConnection to dequeue the message
await Task.Yield();
}
// If we exited because we were cancelled, throw.
cts.Token.ThrowIfCancellationRequested();
// We're free! Unblock onreceived
onReceived.Continue();
});
}
public async Task SSETransportCancelsSendOnStop()
{
var eventStreamTcs = new TaskCompletionSource <object>();
var copyToAsyncTcs = new TaskCompletionSource <object>();
var sendSyncPoint = new SyncPoint();
var mockHttpHandler = new Mock <HttpMessageHandler>();
mockHttpHandler.Protected()
.Setup <Task <HttpResponseMessage> >("SendAsync", ItExpr.IsAny <HttpRequestMessage>(), ItExpr.IsAny <CancellationToken>())
.Returns <HttpRequestMessage, CancellationToken>(async(request, cancellationToken) =>
{
await Task.Yield();
if (request.Headers.Accept?.Contains(new MediaTypeWithQualityHeaderValue("text/event-stream")) == true)
{
// Receive loop started - allow stopping the transport
eventStreamTcs.SetResult(null);
// returns unfinished task to block pipelines
var mockStream = new Mock <Stream>();
mockStream
.Setup(s => s.CopyToAsync(It.IsAny <Stream>(), It.IsAny <int>(), It.IsAny <CancellationToken>()))
.Returns <Stream, int, CancellationToken>(async(stream, bufferSize, t) =>
{
await copyToAsyncTcs.Task;
throw new TaskCanceledException();
});
mockStream.Setup(s => s.CanRead).Returns(true);
return(new HttpResponseMessage {
Content = new StreamContent(mockStream.Object)
});
}
// Throw TaskCanceledException from SSE send's SendAsync on stop
cancellationToken.Register(s => ((SyncPoint)s).Continue(), sendSyncPoint);
await sendSyncPoint.WaitToContinue();
throw new TaskCanceledException();
});
using (var httpClient = new HttpClient(mockHttpHandler.Object))
using (StartVerifiableLog())
{
var sseTransport = new ServerSentEventsTransport(httpClient, LoggerFactory);
await sseTransport.StartAsync(
new Uri("http://fakeuri.org"), TransferFormat.Text).OrTimeout();
await eventStreamTcs.Task;
await sseTransport.Output.WriteAsync(new byte[] { 0x42 });
// For send request to be in progress
await sendSyncPoint.WaitForSyncPoint();
var stopTask = sseTransport.StopAsync();
copyToAsyncTcs.SetResult(null);
sendSyncPoint.Continue();
await stopTask;
}
}
public Task StopAsyncWhileAbortingTriggersClosedEventWithoutException()
{
return(WithConnectionAsync(CreateConnection(transport: new TestTransport(onTransportStop: SyncPoint.Create(2, out var syncPoints))), async(connection, closed) =>
{
// Start the connection
await connection.StartAsync(TransferFormat.Text).OrTimeout();
// Abort with an error
var expected = new Exception("Ruh roh!");
var abortTask = connection.AbortAsync(expected).OrTimeout();
// Wait to reach the first sync point
await syncPoints[0].WaitForSyncPoint().OrTimeout();
// Stop normally, without a sync point.
// This should clear the exception, meaning Closed will not "throw"
syncPoints[1].Continue();
await connection.StopAsync();
await closed.OrTimeout();
// Clean-up
syncPoints[0].Continue();
await abortTask.OrTimeout();
}));
}
public Task AbortAsyncWhileStoppingTriggersClosedEventWithException()
{
return(WithConnectionAsync(CreateConnection(transport: new TestTransport(onTransportStop: SyncPoint.Create(2, out var syncPoints))), async(connection, closed) =>
{
// Start the connection
await connection.StartAsync(TransferFormat.Text).OrTimeout();
// Stop normally
var stopTask = connection.StopAsync().OrTimeout();
// Wait to reach the first sync point
await syncPoints[0].WaitForSyncPoint().OrTimeout();
// Abort with an error
var expected = new Exception("Ruh roh!");
var abortTask = connection.AbortAsync(expected).OrTimeout();
// Wait for the sync point to hit again
await syncPoints[1].WaitForSyncPoint().OrTimeout();
// Release sync point 0
syncPoints[0].Continue();
// We should close with the error from Abort (because it was set by the call to Abort even though Stop triggered the close)
var actual = await Assert.ThrowsAsync <Exception>(async() => await closed.OrTimeout());
Assert.Same(expected, actual);
// Clean-up
syncPoints[1].Continue();
await Task.WhenAll(stopTask, abortTask).OrTimeout();
}));
}