[Part3] Support Activity Status and status description in OTLP Exporter.

src/OpenTelemetry.Exporter.OpenTelemetryProtocol/CHANGELOG.md

@@ -2,6 +2,16 @@
 
 ## Unreleased
 
+* Added support for Activity Status and StatusDescription which were
+  added to Activity from `System.Diagnostics.DiagnosticSource` version 6.0.
+  Prior to version 6.0, setting the status of an Activity was provided by the
+  .NET OpenTelemetry API via the `Activity.SetStatus` extension method in the
+  `OpenTelemetry.Trace` namespace. Internally, this extension method added the
+  status as tags on the Activity: `otel.status_code` and `otel.status_description`.
+  Therefore, to maintain backward compatibility, the exporter falls back to using
+  these tags to infer status.
+ ([#3100](https://github.com/open-telemetry/opentelemetry-dotnet/pull/3100))
+
 * Fixed OTLP metric exporter to default to a periodic 60 second export cycle.
   A bug was introduced in #2717 that caused the OTLP metric export to default
   to a manual export cycle (i.e., requiring an explicit flush). A workaround

src/OpenTelemetry.Exporter.OpenTelemetryProtocol/Implementation/ActivityExtensions.cs

@@ -178,7 +178,7 @@ internal static OtlpTrace.Span ToOtlpSpan(this Activity activity)
                 otlpTags.Tags.Return();
             }
 
-            otlpSpan.Status = ToOtlpStatus(ref otlpTags);
+            otlpSpan.Status = activity.ToOtlpStatus(ref otlpTags);
 
             EventEnumerationState otlpEvents = default;
             activity.EnumerateEvents(ref otlpEvents);
@@ -237,21 +237,39 @@ internal static OtlpCommon.KeyValue ToOtlpAttribute(this KeyValuePair<string, ob
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        private static OtlpTrace.Status ToOtlpStatus(ref TagEnumerationState otlpTags)
+        private static OtlpTrace.Status ToOtlpStatus(this Activity activity, ref TagEnumerationState otlpTags)
         {
-            var status = StatusHelper.GetStatusCodeForTagValue(otlpTags.StatusCode);
-
-            if (!status.HasValue)
+            if (activity.Status == ActivityStatusCode.Unset && StatusHelper.GetStatusCodeForTagValue(otlpTags.StatusCode) == null)
             {
                 return null;
             }
 
-            var otlpStatus = new OtlpTrace.Status
+            OtlpTrace.Status.Types.StatusCode otlpActivityStatusCode = OtlpTrace.Status.Types.StatusCode.Unset;
+            string otlpStatusDescription = null;
+            if (activity.Status != ActivityStatusCode.Unset)
             {
                 // The numerical values of the two enumerations match, a simple cast is enough.
-                Code = (OtlpTrace.Status.Types.StatusCode)(int)status,
-            };
+                otlpActivityStatusCode = (OtlpTrace.Status.Types.StatusCode)(int)activity.Status;
+                if (!string.IsNullOrEmpty(activity.StatusDescription))
+                {
+                    otlpStatusDescription = activity.StatusDescription;
+                }
+            }
+            else
+            {
+                var statusCode = StatusHelper.GetStatusCodeForTagValue(otlpTags.StatusCode);
+                if (statusCode != StatusCode.Unset)
+                {
+                    // The numerical values of the two enumerations match, a simple cast is enough.
+                    otlpActivityStatusCode = (OtlpTrace.Status.Types.StatusCode)(int)statusCode;
+                    if (!string.IsNullOrEmpty(otlpTags.StatusDescription))
+                    {
+                        otlpStatusDescription = otlpTags.StatusDescription;
+                    }
+                }
+            }
 
+            var otlpStatus = new OtlpTrace.Status { Code = otlpActivityStatusCode };
             if (otlpStatus.Code != OtlpTrace.Status.Types.StatusCode.Error)
             {
 #pragma warning disable CS0612 // Type or member is obsolete
@@ -265,9 +283,9 @@ private static OtlpTrace.Status ToOtlpStatus(ref TagEnumerationState otlpTags)
 #pragma warning restore CS0612 // Type or member is obsolete
             }
 
-            if (!string.IsNullOrEmpty(otlpTags.StatusDescription))
+            if (!string.IsNullOrEmpty(otlpStatusDescription))
             {
-                otlpStatus.Message = otlpTags.StatusDescription;
+                otlpStatus.Message = otlpStatusDescription;
             }
 
             return otlpStatus;

test/OpenTelemetry.Exporter.OpenTelemetryProtocol.Tests/OtlpTraceExporterTests.cs

@@ -348,6 +348,97 @@ public void ToOtlpSpanActivitiesWithNullArrayTest()
             Assert.Null(stringArray[2].Value);
         }
 
+        [Theory]
+        [InlineData(ActivityStatusCode.Unset, "")]
+        [InlineData(ActivityStatusCode.Ok, "")]
+        [InlineData(ActivityStatusCode.Error, "error description")]
+        public void ToOtlpSpanNativeActivityStatusTest(ActivityStatusCode expectedStatusCode, string statusDescription)
+        {
+            using var activitySource = new ActivitySource(nameof(this.ToOtlpSpanTest));
+            using var activity = activitySource.StartActivity("Name");
+            activity.SetStatus(expectedStatusCode, statusDescription);
+
+            var otlpSpan = activity.ToOtlpSpan();
+
+            if (expectedStatusCode == ActivityStatusCode.Unset)
+            {
+                Assert.Null(otlpSpan.Status);
+            }
+            else
+            {
+                Assert.NotNull(otlpSpan.Status);
+                Assert.Equal((int)expectedStatusCode, (int)otlpSpan.Status.Code);
+                if (expectedStatusCode == ActivityStatusCode.Error)
+                {
+                    Assert.Equal(statusDescription, otlpSpan.Status.Message);
+                }
+
+                if (expectedStatusCode == ActivityStatusCode.Ok)
+                {
+                    Assert.Empty(otlpSpan.Status.Message);
+                }
+            }
+        }
+
+        [Theory]
+        [InlineData(StatusCode.Unset, "unset", "")]
+        [InlineData(StatusCode.Ok, "Ok", "")]
+        [InlineData(StatusCode.Error, "ERROR", "error description")]
+        public void ToOtlpSpanStatusTagTest(StatusCode expectedStatusCode, string statusCodeTagValue, string statusDescription)
+        {
+            using var activitySource = new ActivitySource(nameof(this.ToOtlpSpanTest));
+            using var activity = activitySource.StartActivity("Name");
+            activity.SetTag(SpanAttributeConstants.StatusCodeKey, statusCodeTagValue);
+            activity.SetTag(SpanAttributeConstants.StatusDescriptionKey, statusDescription);
+
+            var otlpSpan = activity.ToOtlpSpan();
+
+            Assert.NotNull(otlpSpan.Status);
+            Assert.Equal((int)expectedStatusCode, (int)otlpSpan.Status.Code);
+
+            if (expectedStatusCode == StatusCode.Error)
+            {
+                Assert.Equal(statusDescription, otlpSpan.Status.Message);
+            }
+            else
+            {
+                Assert.Empty(otlpSpan.Status.Message);
+            }
+        }
+
+        [Fact]
+        public void ToOtlpSpanActivityStatusTakesPrecedenceOverStatusTagsWhenActivityStatusCodeIsOk()
+        {
+            using var activitySource = new ActivitySource(nameof(this.ToOtlpSpanTest));
+            using var activity = activitySource.StartActivity("Name");
+            const string TagDescriptionOnError = "Description when TagStatusCode is Error.";
+            activity.SetStatus(ActivityStatusCode.Ok);
+            activity.SetTag(SpanAttributeConstants.StatusCodeKey, "ERROR");
+            activity.SetTag(SpanAttributeConstants.StatusDescriptionKey, TagDescriptionOnError);
+
+            var otlpSpan = activity.ToOtlpSpan();
+
+            Assert.NotNull(otlpSpan.Status);
+            Assert.Equal((int)ActivityStatusCode.Ok, (int)otlpSpan.Status.Code);
+            Assert.Empty(otlpSpan.Status.Message);
+        }
+
+        [Fact]
+        public void ToOtlpSpanActivityStatusTakesPrecedenceOverStatusTagsWhenActivityStatusCodeIsError()
+        {
+            using var activitySource = new ActivitySource(nameof(this.ToOtlpSpanTest));
+            using var activity = activitySource.StartActivity("Name");
+            const string StatusDescriptionOnError = "Description when ActivityStatusCode is Error.";
+            activity.SetStatus(ActivityStatusCode.Error, StatusDescriptionOnError);
+            activity.SetTag(SpanAttributeConstants.StatusCodeKey, "OK");
+
+            var otlpSpan = activity.ToOtlpSpan();
+
+            Assert.NotNull(otlpSpan.Status);
+            Assert.Equal((int)ActivityStatusCode.Error, (int)otlpSpan.Status.Code);
+            Assert.Equal(StatusDescriptionOnError, otlpSpan.Status.Message);
+        }
+
         [Fact]
         public void ToOtlpSpanPeerServiceTest()
         {