public void LogsDataLossEventsWhenExceptionisNull()
{
using (var listener = new TestEventListener())
{
// Arrange:
const long AllKeywords = -1;
listener.EnableEvents(TelemetryChannelEventSource.Log, EventLevel.LogAlways, (EventKeywords)AllKeywords);
Transmission enqueuedTransmission = null;
var transmitter = new StubTransmitter(new BackoffLogicManager(TimeSpan.FromMilliseconds(10)))
{
OnEnqueue = transmission => { enqueuedTransmission = transmission; }
};
var policy = new ErrorHandlingTransmissionPolicy();
policy.Initialize(transmitter);
var failedTransmission = new StubTransmission();
// Act:
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(failedTransmission, null, null));
// Assert:
var traces = listener.Messages.Where(item => item.Level == EventLevel.Error).ToList();
Assert.AreEqual(1, traces.Count);
Assert.AreEqual(69, traces[0].EventId); // failed to send
Assert.AreEqual("Unknown Exception Message", traces[0].Payload[1]);
}
}
public void NoWarningLogsWhenResponseIsPartiallSuccess()
{
// ErrorHandlingTransmissionPolicy does retry only for a whitelisted set of status codes. For
// partial success (206) status, there should be no warnings as this is handled by separate
// Retry policy. This test is to validate that no warning is logged.
using (var listener = new TestEventListener())
{
// Arrange:
const long AllKeywords = -1;
listener.EnableEvents(TelemetryChannelEventSource.Log, EventLevel.LogAlways, (EventKeywords)AllKeywords);
Transmission enqueuedTransmission = null;
var transmitter = new StubTransmitter(new BackoffLogicManager(TimeSpan.FromMilliseconds(10)))
{
OnEnqueue = transmission => { enqueuedTransmission = transmission; }
};
var policy = new ErrorHandlingTransmissionPolicy();
policy.Initialize(transmitter);
var failedTransmission = new StubTransmission();
// Act:
var res = new HttpWebResponseWrapper();
res.StatusCode = 206; // Sucess
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(failedTransmission, null, res));
// Assert:
var traces = listener.Messages.Where(item => item.Level == EventLevel.Warning).ToList();
Assert.AreEqual(0, traces.Count);
}
}
public void RetriesFailedTransmissionInfinitely()
{
Transmission enqueuedTransmission = null;
var transmitter = new StubTransmitter(new TestableBackoffLogicManager(TimeSpan.FromMilliseconds(10)));
transmitter.OnEnqueue = transmission =>
{
enqueuedTransmission = transmission;
};
var policy = new ErrorHandlingTransmissionPolicy();
policy.Initialize(transmitter);
var failedTransmission = new StubTransmission();
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(failedTransmission, new Exception("Error"), new HttpWebResponseWrapper()
{
StatusCode = ResponseStatusCodes.InternalServerError
}));
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(failedTransmission, new Exception("Error"), new HttpWebResponseWrapper()
{
StatusCode = ResponseStatusCodes.InternalServerError
}));
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(failedTransmission, new Exception("Error"), new HttpWebResponseWrapper()
{
StatusCode = ResponseStatusCodes.InternalServerError
}));
Assert.AreSame(failedTransmission, enqueuedTransmission);
}
public void LogsAdditionalTracesIfResponseIsProvided()
{
using (var listener = new TestEventListener())
{
// Arrange:
const long AllKeywords = -1;
listener.EnableEvents(TelemetryChannelEventSource.Log, EventLevel.LogAlways, (EventKeywords)AllKeywords);
Transmission enqueuedTransmission = null;
var transmitter = new StubTransmitter(new BackoffLogicManager(TimeSpan.FromMilliseconds(10)))
{
OnEnqueue = transmission => { enqueuedTransmission = transmission; }
};
var policy = new ErrorHandlingTransmissionPolicy();
policy.Initialize(transmitter);
var failedTransmission = new StubTransmission();
var response = new HttpWebResponseWrapper {
Content = BackendResponseHelper.CreateBackendResponse(2, 1, new[] { "123" })
};
// Act:
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(failedTransmission, CreateException(statusCode: 408), response));
// Assert:
var traces = listener.Messages.Where(item => item.Level == EventLevel.Warning).ToList();
Assert.AreEqual(2, traces.Count);
Assert.AreEqual(23, traces[0].EventId); // failed to send
Assert.AreEqual(7, traces[1].EventId); // additional trace
Assert.AreEqual("Explanation", traces[1].Payload[0]);
}
}
public void LogsWarningWhenDataLossIntentional()
{
// ErrorHandlingTransmissionPolicy does retry only for a whitelisted set of status codes. For
// others telemetry is dropped. This test is to validate that those are logged.
using (var listener = new TestEventListener())
{
// Arrange:
const long AllKeywords = -1;
listener.EnableEvents(TelemetryChannelEventSource.Log, EventLevel.LogAlways, (EventKeywords)AllKeywords);
Transmission enqueuedTransmission = null;
var transmitter = new StubTransmitter(new BackoffLogicManager(TimeSpan.FromMilliseconds(10)))
{
OnEnqueue = transmission => { enqueuedTransmission = transmission; }
};
var policy = new ErrorHandlingTransmissionPolicy();
policy.Initialize(transmitter);
var failedTransmission = new StubTransmission();
// Act:
var res = new HttpWebResponseWrapper();
res.StatusCode = 8989; // some status code not whitelisted for retry.
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(failedTransmission, null, res));
// Assert:
var traces = listener.Messages.Where(item => item.Level == EventLevel.Warning).ToList();
Assert.AreEqual(1, traces.Count);
Assert.AreEqual(71, traces[0].EventId); // failed to send
Assert.AreEqual("8989", traces[0].Payload[1]);
}
}
public void KeepsTransmissionSenderPausedWhenAdditionalTransmissionsFail()
{
var transmitter = new StubTransmitter(new TestableBackoffLogicManager(TimeSpan.FromMinutes(1)));
var policy = new ErrorHandlingTransmissionPolicy();
policy.Initialize(transmitter);
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(new StubTransmission(), CreateException(statusCode: 408)));
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(new StubTransmission(), CreateException(statusCode: 408)));
Thread.Sleep(TimeSpan.FromMilliseconds(30));
Assert.AreEqual(0, policy.MaxSenderCapacity);
}
private static void CatchesAndLogsExceptionThrownByTransmitter(ErrorHandlingTransmissionPolicy policy, StubTransmitter transmitter, Exception exception)
{
policy.Initialize(transmitter);
using (var listener = new TestEventListener())
{
const long AllKeywords = -1;
listener.EnableEvents(TelemetryChannelEventSource.Log, EventLevel.Warning, (EventKeywords)AllKeywords);
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(new StubTransmission(), CreateException(statusCode: 408)));
EventWrittenEventArgs error = listener.Messages.First(args => args.EventId == 23);
AssertEx.Contains(exception.Message, (string)error.Payload[1], StringComparison.Ordinal);
}
}
public void StopsTransmissionSendingWhenTransmissionTimesOut()
{
var policyApplied = new AutoResetEvent(false);
var transmitter = new StubTransmitter(new TestableBackoffLogicManager(TimeSpan.FromSeconds(10)));
transmitter.OnApplyPolicies = () =>
{
policyApplied.Set();
};
var policy = new ErrorHandlingTransmissionPolicy();
policy.Initialize(transmitter);
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(new StubTransmission(), CreateException(statusCode: 408)));
Assert.IsTrue(policyApplied.WaitOne(100));
Assert.AreEqual(0, policy.MaxSenderCapacity);
}
public void ResumesTransmissionSenderAfterPauseDuration()
{
var policyApplied = new AutoResetEvent(false);
var transmitter = new StubTransmitter(new TestableBackoffLogicManager(TimeSpan.FromMilliseconds(1)));
transmitter.OnApplyPolicies = () =>
{
policyApplied.Set();
};
var policy = new ErrorHandlingTransmissionPolicy();
policy.Initialize(transmitter);
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(new StubTransmission(), CreateException(statusCode: 408)));
Assert.True(policyApplied.WaitOne(100));
Assert.True(policyApplied.WaitOne(100));
Assert.Null(policy.MaxSenderCapacity);
}
public void RetriesFailedTransmissionIfItsNumberOfAttemptsDidNotReachMaximum()
{
Transmission enqueuedTransmission = null;
var transmitter = new StubTransmitter();
transmitter.OnEnqueue = transmission =>
{
enqueuedTransmission = transmission;
};
var policy = new ErrorHandlingTransmissionPolicy();
policy.Initialize(transmitter);
var failedTransmission = new StubTransmission();
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(failedTransmission, CreateException(statusCode: 408)));
Assert.AreSame(failedTransmission, enqueuedTransmission);
}
public void DoesNotRetrySuccessfulTransmission()
{
Transmission enqueuedTransmission = null;
var transmitter = new StubTransmitter();
transmitter.OnEnqueue = transmission =>
{
enqueuedTransmission = transmission;
};
var policy = new ErrorHandlingTransmissionPolicy();
policy.Initialize(transmitter);
var successfulTransmission = new StubTransmission();
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(successfulTransmission));
Assert.IsNull(enqueuedTransmission);
Assert.AreEqual(0, transmitter.BackoffLogicManager.ConsecutiveErrors);
}
private void ResumesTransmissionSenderAfterPauseDuration(int responseStatusCode)
{
var policyApplied = new AutoResetEvent(false);
var transmitter = new StubTransmitter(new TestableBackoffLogicManager(TimeSpan.FromMilliseconds(1)));
transmitter.OnApplyPolicies = () => { policyApplied.Set(); };
var policy = new ErrorHandlingTransmissionPolicy();
policy.Initialize(transmitter);
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(new StubTransmission(),
new Exception("Error"),
new HttpWebResponseWrapper()
{
StatusCode = responseStatusCode
}));
Assert.IsTrue(policyApplied.WaitOne(100));
Assert.IsTrue(policyApplied.WaitOne(100));
Assert.IsNull(policy.MaxSenderCapacity);
}
public void RetriesFailedTransmissionInfinitely()
{
Transmission enqueuedTransmission = null;
var transmitter = new StubTransmitter(new TestableBackoffLogicManager(TimeSpan.FromMilliseconds(10)));
transmitter.OnEnqueue = transmission =>
{
enqueuedTransmission = transmission;
};
var policy = new ErrorHandlingTransmissionPolicy();
policy.Initialize(transmitter);
var failedTransmission = new StubTransmission();
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(failedTransmission, CreateException(statusCode: 408)));
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(failedTransmission, CreateException(statusCode: 408)));
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(failedTransmission, CreateException(statusCode: 408)));
Assert.AreSame(failedTransmission, enqueuedTransmission);
}
public void RetriesFailedTransmissionIfItsNumberOfAttemptsDidNotReachMaximum()
{
Transmission enqueuedTransmission = null;
var transmitter = new StubTransmitter();
transmitter.OnEnqueue = transmission =>
{
enqueuedTransmission = transmission;
};
var policy = new ErrorHandlingTransmissionPolicy();
policy.Initialize(transmitter);
var failedTransmission = new StubTransmission();
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(failedTransmission, new Exception("Error"), new HttpWebResponseWrapper()
{
StatusCode = ResponseStatusCodes.InternalServerError
}));
Assert.AreSame(failedTransmission, enqueuedTransmission);
}
public void RetriesFailedTransmissionIfItsNumberOfAttemptsDidNotReachMaximum()
{
Transmission enqueuedTransmission = null;
var transmitter = new StubTransmitter();
transmitter.OnEnqueue = transmission =>
{
enqueuedTransmission = transmission;
};
var policy = new ErrorHandlingTransmissionPolicy();
policy.Initialize(transmitter);
var failedTransmission = new StubTransmission();
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(failedTransmission, CreateException(statusCode: 408)));
Assert.Same(failedTransmission, enqueuedTransmission);
}
private static void CatchesAndLogsExceptionThrownByTransmitter(ErrorHandlingTransmissionPolicy policy, StubTransmitter transmitter, Exception exception)
{
policy.Initialize(transmitter);
using (var listener = new TestEventListener())
{
const long AllKeywords = -1;
listener.EnableEvents(TelemetryChannelEventSource.Log, EventLevel.Warning, (EventKeywords)AllKeywords);
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(new StubTransmission(), CreateException(statusCode: 408)));
EventWrittenEventArgs error = listener.Messages.First(args => args.EventId == 23);
Assert.Contains(exception.Message, (string)error.Payload[1], StringComparison.Ordinal);
}
}
public void DoesNotRetrySuccessfulTransmission()
{
Transmission enqueuedTransmission = null;
var transmitter = new StubTransmitter();
transmitter.OnEnqueue = transmission =>
{
enqueuedTransmission = transmission;
};
var policy = new ErrorHandlingTransmissionPolicy();
policy.Initialize(transmitter);
var successfulTransmission = new StubTransmission();
transmitter.OnTransmissionSent(new TransmissionProcessedEventArgs(successfulTransmission));
Assert.Null(enqueuedTransmission);
Assert.Equal(0, policy.ConsecutiveErrors);
}