feat!: don't trace 301, 305-399 or 401-404 responses by default (#5632)

Author: jamescrosswell

src/Sentry/SentryOptions.cs

@@ -949,9 +949,15 @@ public IDiagnosticLogger? DiagnosticLogger
 
     /// <summary>
     /// <para>Transactions will be dropped if the HTTP Response status code matches any of the configured ranges.</para>
-    /// <para>Defaults to an empty collection (all transactions are captured regardless of status code).</para>
+    /// <para>Defaults to 301, 305-399 and 401-404. 302 and 303 are traced, as they commonly redirect after a successful form POST.</para>
+    /// <para>Clear the collection to capture transactions regardless of status code.</para>
     /// </summary>
-    public IList<HttpStatusCodeRange> TraceIgnoreStatusCodes { get; set; } = [];
+    public IList<HttpStatusCodeRange> TraceIgnoreStatusCodes { get; set; } = new List<HttpStatusCodeRange>
+    {
+        301,
+        (305, 399),
+        (401, 404)
+    };
 
     // The default failed request target list will match anything, but adding to the list should clear that.
     private Lazy<IList<StringOrRegex>> _failedRequestTargets = new(() =>

test/Sentry.AspNetCore.Tests/IntegrationMockedBackgroundWorker.cs

@@ -338,4 +338,42 @@ public async Task Environment_BothOnOptionsAndEnvVar_ValueFromOption()
                 .Environment == expected
         ));
     }
+
+    [Fact]
+    public async Task NotFoundRequest_ByDefault_NoTransactionCaptured()
+    {
+        Configure = o => o.TracesSampleRate = 1;
+        ConfigureApp = app => app.UseSentryTracing();
+
+        Build();
+        _ = await HttpClient.GetAsync("/");
+        _ = await HttpClient.GetAsync("/missing");
+
+        _ = Worker.Received(1).EnqueueEnvelope(Arg.Is<Envelope>(e => HasTransaction(e, "GET /")));
+        _ = Worker.DidNotReceive().EnqueueEnvelope(Arg.Is<Envelope>(e => HasTransaction(e, "GET /missing")));
+    }
+
+    [Fact]
+    public async Task NotFoundRequest_TraceIgnoreStatusCodesCleared_TransactionCaptured()
+    {
+        Configure = o =>
+        {
+            o.TracesSampleRate = 1;
+            o.TraceIgnoreStatusCodes.Clear();
+        };
+        ConfigureApp = app => app.UseSentryTracing();
+
+        Build();
+        _ = await HttpClient.GetAsync("/missing");
+
+        _ = Worker.Received(1).EnqueueEnvelope(Arg.Is<Envelope>(e => HasTransaction(e, "GET /missing")));
+    }
+
+    private static bool HasTransaction(Envelope envelope, string name) =>
+        envelope.Items
+            .Select(i => i.Payload)
+            .OfType<JsonSerializable>()
+            .Select(i => i.Source)
+            .OfType<SentryTransaction>()
+            .Any(t => t.Name == name);
 }

test/Sentry.Tests/BindableSentryOptionsTests.cs

@@ -26,5 +26,42 @@ public void ApplyTo_SetsOptionsFromConfig()
         // Assert
         AssertContainsExpectedPropertyValues(actual);
     }
+
+    [Fact]
+    public void ApplyTo_TraceIgnoreStatusCodesNotConfigured_KeepsDefault()
+    {
+        // Arrange
+        var actual = new SentryOptions();
+        var bindable = new BindableSentryOptions();
+
+        // Act
+        new ConfigurationBuilder().Build().Bind(bindable);
+        bindable.ApplyTo(actual);
+
+        // Assert
+        actual.TraceIgnoreStatusCodes.Should().Equal(new SentryOptions().TraceIgnoreStatusCodes);
+    }
+
+    [Fact]
+    public void ApplyTo_TraceIgnoreStatusCodesConfigured_ReplacesDefault()
+    {
+        // Arrange
+        var actual = new SentryOptions();
+        var bindable = new BindableSentryOptions();
+        var config = new ConfigurationBuilder()
+            .AddInMemoryCollection(new Dictionary<string, string>
+            {
+                ["TraceIgnoreStatusCodes:0"] = "404",
+                ["TraceIgnoreStatusCodes:1"] = "500"
+            })
+            .Build();
+
+        // Act
+        config.Bind(bindable);
+        bindable.ApplyTo(actual);
+
+        // Assert
+        actual.TraceIgnoreStatusCodes.Should().Equal(new HttpStatusCodeRange(404), new HttpStatusCodeRange(500));
+    }
 }
 #endif

test/Sentry.Tests/TraceIgnoreStatusCodeTransactionProcessorTests.cs

@@ -4,15 +4,8 @@ namespace Sentry.Tests;
 
 public class TraceIgnoreStatusCodeTransactionProcessorTests
 {
-    private static SentryOptions OptionsWithIgnoredCodes(params HttpStatusCodeRange[] ranges)
-    {
-        var options = new SentryOptions();
-        foreach (var range in ranges)
-        {
-            options.TraceIgnoreStatusCodes.Add(range);
-        }
-        return options;
-    }
+    private static SentryOptions OptionsWithIgnoredCodes(params HttpStatusCodeRange[] ranges) =>
+        new() { TraceIgnoreStatusCodes = [.. ranges] };
 
     private static SentryTransaction TransactionWithStatusCode(int statusCode)
     {
@@ -21,11 +14,55 @@ private static SentryTransaction TransactionWithStatusCode(int statusCode)
         return transaction;
     }
 
+    [Theory]
+    [InlineData(301)]
+    [InlineData(305)]
+    [InlineData(307)]
+    [InlineData(308)]
+    [InlineData(399)]
+    [InlineData(401)]
+    [InlineData(403)]
+    [InlineData(404)]
+    public void Process_DefaultOptions_DropsIgnoredStatusCode(int statusCode)
+    {
+        // Arrange
+        var processor = new TraceIgnoreStatusCodeTransactionProcessor(new SentryOptions());
+        var transaction = TransactionWithStatusCode(statusCode);
+
+        // Act
+        var result = processor.Process(transaction);
+
+        // Assert
+        result.Should().BeNull();
+    }
+
+    [Theory]
+    [InlineData(200)]
+    [InlineData(300)]
+    [InlineData(302)]
+    [InlineData(303)]
+    [InlineData(304)]
+    [InlineData(400)]
+    [InlineData(405)]
+    [InlineData(500)]
+    public void Process_DefaultOptions_ReturnsTransaction(int statusCode)
+    {
+        // Arrange
+        var processor = new TraceIgnoreStatusCodeTransactionProcessor(new SentryOptions());
+        var transaction = TransactionWithStatusCode(statusCode);
+
+        // Act
+        var result = processor.Process(transaction);
+
+        // Assert
+        result.Should().BeSameAs(transaction);
+    }
+
     [Fact]
     public void Process_EmptyIgnoreList_ReturnsTransaction()
     {
         // Arrange
-        var options = new SentryOptions();
+        var options = OptionsWithIgnoredCodes();
         var processor = new TraceIgnoreStatusCodeTransactionProcessor(options);
         var transaction = TransactionWithStatusCode(404);