public static Metadata ProcessHeaders(Metadata headers)
{
if (headers == null)
{
throw new ArgumentNullException(nameof(headers));
}
Metadata.Entry trackingEntry = headers.FirstOrDefault(x => string.CompareOrdinal(x.Key, s_TrackingContextKeyName) == 0);
// Retrieve the tracking context from the message header, if it exists.
if (trackingEntry != null)
{
// If an tracking context exists in the message header, always use it to replace the ambient context.
TrackingContext tc = TrackingContext.DeSerialize(trackingEntry.ValueBytes);
tc.SetAsCurrent();
}
else
{
// If no tracking context exists then create one.
TrackingContext.NewCurrentIfEmpty();
Debug.Assert(TrackingContext.Current != null);
// Copy the tracking context to the message header.
byte[] byteArray = TrackingContext.Serialize(TrackingContext.Current);
headers.Add(s_TrackingContextKeyName, byteArray);
}
return(headers);
}
private static string CreateAndSerializeNewTrackingContext()
{
TrackingContext.NewCurrentIfEmpty();
Debug.Assert(TrackingContext.Current != null);
byte[] byteArray = TrackingContext.Serialize(TrackingContext.Current);
return(byteArray.ByteArrayToBase64String());
}
public async Task Startup_GivenTrackingContextMiddleware_WhenTrackingContextSent_ThenNoTrackingContextReturned()
{
var textWriterSink = new StringWriter();
var hostBuilder = new HostBuilder()
.ConfigureWebHost(webHost =>
{
webHost.UseTestServer();
webHost.UseStartup <Startup>();
webHost.ConfigureServices((services) => StartupBase.ConfigureServicesWithLogSink(
services,
textWriterSink,
$"{{{nameof(TrackingContext.CallChainId)}}}{textWriterSink.NewLine}"));
});
var host = await hostBuilder.StartAsync();
var client = host.GetTestClient();
TrackingContext.NewCurrentIfEmpty();
TrackingContext currentContext = TrackingContext.Current;
currentContext.Should().NotBeNull();
var requestMessage = new HttpRequestMessage(HttpMethod.Get, @"/api/values");
string tcHeader = TrackingContext.Serialize(currentContext).ByteArrayToBase64String();
requestMessage.Headers.Add(TrackingContextHelper.TrackingContextKeyName, tcHeader);
var response = await client.SendAsync(requestMessage);
response.EnsureSuccessStatusCode();
response.Headers.TryGetValues(TrackingContextHelper.TrackingContextKeyName, out IEnumerable <string> values).Should().BeFalse();
TrackingContext.Current.Should().NotBeNull();
TrackingContext.Current.Should().BeEquivalentTo(currentContext);
IList <string> callChainIds = textWriterSink
.ToString()
.Split(textWriterSink.NewLine, StringSplitOptions.RemoveEmptyEntries)
.ToList();
callChainIds.Count().Should().Be(10);
// The call chain ID should be different on the server side.
callChainIds.All(x => !x.Equals(currentContext.CallChainId.ToDashedString())).Should().BeTrue();
}
public void TrackingContext_SerializeAndDeserialize_Success()
{
var extraHeaders = new Dictionary <string, string>()
{
{ "AAA", "AAA" },
{ "BBB", "BBB" },
};
var tc1 = new TrackingContext(
Guid.NewGuid(),
DateTime.UtcNow,
extraHeaders);
byte[] bytes = TrackingContext.Serialize(tc1);
TrackingContext tc2 = TrackingContext.DeSerialize(bytes);
Assert.AreNotEqual(0, bytes.Length);
Assert.AreEqual(tc1.CallChainId, tc2.CallChainId);
Assert.AreEqual(tc1.OriginatorUtcTimestamp, tc2.OriginatorUtcTimestamp);
CollectionAssert.AreEquivalent(tc1.ExtraHeaders.ToList(), tc2.ExtraHeaders.ToList());
}
public void TrackingContext_GivenSerializeAndDeserialize_ThenSuccess()
{
var extraHeaders = new Dictionary <string, string>()
{
{ "AAA", "AAA" },
{ "BBB", "BBB" },
};
var tc1 = new TrackingContext(
Guid.NewGuid(),
DateTime.UtcNow,
extraHeaders);
byte[] bytes = TrackingContext.Serialize(tc1);
TrackingContext tc2 = TrackingContext.DeSerialize(bytes);
bytes.Should().NotBeEmpty();
tc2.CallChainId.Should().Be(tc1.CallChainId);
tc2.OriginatorUtcTimestamp.Should().Be(tc1.OriginatorUtcTimestamp);
tc2.ExtraHeaders.ToList().Should().BeEquivalentTo(tc1.ExtraHeaders.ToList());
}
public async Task Startup_GivenTrackingContextWithMergeAndOverwriteMiddleware_WhenTrackingContextSent_ThenTrackingContextReturned()
{
var textWriterSink = new StringWriter();
var hostBuilder = new HostBuilder()
.ConfigureWebHost(webHost =>
{
webHost.UseTestServer();
webHost.UseStartup <StartupWithMergeAndOverwrite>();
webHost.ConfigureServices((services) => StartupBase.ConfigureServicesWithLogSink(
services,
textWriterSink,
$"{{{StartupBase.CountryOfOriginName}}}{textWriterSink.NewLine}"));
});
var host = await hostBuilder.StartAsync();
var client = host.GetTestClient();
string headerKey = Guid.NewGuid().ToFlatString();
string headerValue = Guid.NewGuid().ToFlatString();
TrackingContext.NewCurrentIfEmpty(new Dictionary <string, string>()
{
{ headerKey, headerValue },
{ StartupBase.CountryOfOriginName, @"Germany" }
});
TrackingContext currentContext = TrackingContext.Current;
currentContext.Should().NotBeNull();
var requestMessage = new HttpRequestMessage(HttpMethod.Get, @"/api/values");
string tcHeader = TrackingContext.Serialize(currentContext).ByteArrayToBase64String();
requestMessage.Headers.Add(TrackingContextHelper.TrackingContextKeyName, tcHeader);
var response = await client.SendAsync(requestMessage);
response.EnsureSuccessStatusCode();
response.Headers.TryGetValues(TrackingContextHelper.TrackingContextKeyName, out IEnumerable <string> values).Should().BeTrue();
string tcBase64 = values.First();
TrackingContext tc = TrackingContext.DeSerialize(tcBase64.Base64StringToByteArray());
tc.CallChainId.Should().NotBeEmpty();
tc.OriginatorUtcTimestamp.Should().BeCloseTo(DateTime.UtcNow, 10000);
tc.ExtraHeaders.Count.Should().Be(4);
tc.ExtraHeaders[headerKey].Should().Be(headerValue);
tc.ExtraHeaders[StartupBase.TraceIdentifierName].Should().NotBeNullOrWhiteSpace();
tc.ExtraHeaders[StartupBase.CountryOfOriginName].Should().Be(@"France");
tc.ExtraHeaders[StartupBase.RandomStringGeneratedWitEachCallName].Should().NotBeNullOrWhiteSpace();
TrackingContext.Current.Should().NotBeNull();
TrackingContext.Current.Should().BeEquivalentTo(currentContext);
IList <string> countriesOfOrigin = textWriterSink
.ToString()
.Split(textWriterSink.NewLine, StringSplitOptions.RemoveEmptyEntries)
.ToList();
countriesOfOrigin.Count().Should().Be(10);
countriesOfOrigin.All(x => x.Equals(tc.ExtraHeaders[StartupBase.CountryOfOriginName])).Should().BeTrue();
}
