Profiler fails with some S3 Errors #7364
Description
When trying to trace an endpoint, we had an error uploading an S3 file (permissions) and it caused the endpoint trace not to appear in datadog at all. Turning on the trace debugging, I found this in the logs:
025-08-07 14:08:28.275 -04:00 [ERR] Exception occurred when calling the CallTarget integration continuation. System.NullReferenceException: Object reference not set to an instance of an object.
at AWSSDK_S3__885C28607F98E604.Amazon_S3_Model_PutObjectResponse.Datadog_Trace_ClrProfiler_AutoInstrumentation_AWS_S3_IS3EtagResponse_30.get_ETag()
at Datadog.Trace.ClrProfiler.AutoInstrumentation.AWS.S3.ObjectManagement.PutObjectAsyncIntegration.OnAsyncMethodEnd[TTarget,TReturn](TTarget instance, TReturn returnValue, Exception exception, CallTargetState& state) in /_/tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/AWS/S3/ObjectManagement/PutObjectAsyncIntegration.cs:line 54
at PutObjectAsyncIntegration.OnAsyncMethodEnd.AmazonS3Client.PutObjectResponse(AmazonS3Client, PutObjectResponse, Exception, CallTargetState&)
at Datadog.Trace.ClrProfiler.CallTarget.Handlers.Continuations.TaskContinuationGenerator`4.SyncCallbackHandler.ContinuationAction(Task`1 previousTask, TTarget target, CallTargetState state)
{ MachineName: ".", Process: "[1209 Seeds.EntryPoin]", AppDomain: "[1 Seeds.EntryPoints.Api]", AssemblyLoadContext: "\"\" Datadog.Trace.ClrProfiler.Managed.Loader.ManagedProfilerAssemblyLoadContext #1", TracerVersion: "3.23.0.0" }
It looks like returnValue is a nullable object in the method signature below, but there's no guard against a null reference in the method itself, and that's what I seem to be running into.
https://github.com/DataDog/dd-trace-dotnet/blame/015d21801674f10d8d72c17276723ec9c322df69/tracer/src/Datadog.Trace/ClrProfiler/AutoInstrumentation/AWS/S3/ObjectManagement/PutObjectAsyncIntegration.cs#L54