fix(logs): do not capture log on user callback exceptions

Author: Flash0ver

src/Sentry/SentryStructuredLogger.cs

@@ -134,7 +134,7 @@ private void CaptureLog(SentryLogLevel level, string template, object[]? paramet
         }
         catch (FormatException e)
         {
-            _options.DiagnosticLogger?.LogError(e, "Template string does not match the provided argument.");
+            _options.DiagnosticLogger?.LogError(e, "Template string does not match the provided argument. The Log will be dropped.");
             return;
         }
 
@@ -151,9 +151,7 @@ private void CaptureLog(SentryLogLevel level, string template, object[]? paramet
         }
         catch (Exception e)
         {
-            //TODO: change to Diagnostic Logger (if enabled)
-            // see https://github.com/getsentry/sentry-dotnet/issues/4132
-            Console.WriteLine(e);
+            _options.DiagnosticLogger?.LogError(e, "The configureLog callback threw an exception. The Log will be dropped.");
             return;
         }
 
@@ -168,9 +166,7 @@ private void CaptureLog(SentryLogLevel level, string template, object[]? paramet
             }
             catch (Exception e)
             {
-                //TODO: change to Diagnostic Logger (if enabled)
-                // see https://github.com/getsentry/sentry-dotnet/issues/4132
-                Console.WriteLine(e);
+                _options.DiagnosticLogger?.LogError(e, "The BeforeSendLog callback threw an exception. The Log will be dropped.");
                 return;
             }
         }

test/Sentry.Tests/SentryStructuredLoggerTests.cs

@@ -164,15 +164,53 @@ public void Log_InvalidFormat_DoesNotCaptureEnvelope()
         _fixture.Hub.Received(0).CaptureEnvelope(Arg.Any<Envelope>());
         var entry = _fixture.DiagnosticLogger.Entries.Should().ContainSingle().Which;
         entry.Level.Should().Be(SentryLevel.Error);
-        entry.Message.Should().Be("Template string does not match the provided argument.");
+        entry.Message.Should().Be("Template string does not match the provided argument. The Log will be dropped.");
         entry.Exception.Should().BeOfType<FormatException>();
         entry.Args.Should().BeEmpty();
     }
 
+    [Fact]
+    public void Log_InvalidConfigureLog_DoesNotCaptureEnvelope()
+    {
+        _fixture.Options.EnableLogs = true;
+        var logger = _fixture.GetSut();
+
+        logger.LogTrace("Template string with arguments: {0}, {1}, {2}, {3}", ["string", true, 1, 2.2], Throw);
+
+        _fixture.Hub.Received(0).CaptureEnvelope(Arg.Any<Envelope>());
+        var entry = _fixture.DiagnosticLogger.Entries.Should().ContainSingle().Which;
+        entry.Level.Should().Be(SentryLevel.Error);
+        entry.Message.Should().Be("The configureLog callback threw an exception. The Log will be dropped.");
+        entry.Exception.Should().BeOfType<InvalidOperationException>();
+        entry.Args.Should().BeEmpty();
+    }
+
+    [Fact]
+    public void Log_InvalidBeforeSendLog_DoesNotCaptureEnvelope()
+    {
+        _fixture.Options.EnableLogs = true;
+        _fixture.Options.SetBeforeSendLog(static (SentryLog log) => throw new InvalidOperationException());
+        var logger = _fixture.GetSut();
+
+        logger.LogTrace("Template string with arguments: {0}, {1}, {2}, {3}", ["string", true, 1, 2.2]);
+
+        _fixture.Hub.Received(0).CaptureEnvelope(Arg.Any<Envelope>());
+        var entry = _fixture.DiagnosticLogger.Entries.Should().ContainSingle().Which;
+        entry.Level.Should().Be(SentryLevel.Error);
+        entry.Message.Should().Be("The BeforeSendLog callback threw an exception. The Log will be dropped.");
+        entry.Exception.Should().BeOfType<InvalidOperationException>();
+        entry.Args.Should().BeEmpty();
+    }
+
     private static void ConfigureLog(SentryLog log)
     {
         log.SetAttribute("attribute-key", "attribute-value");
     }
+
+    private static void Throw(SentryLog log)
+    {
+        throw new InvalidOperationException();
+    }
 }
 
 file static class AssertionExtensions