[OTLP] Avoid redundant allocations and log HTTP export success (#6562)

Author: martincostello

src/OpenTelemetry.Exporter.OpenTelemetryProtocol/Implementation/ExportClient/OtlpGrpcExportClient.cs

@@ -67,7 +67,7 @@ public override ExportClientResponse SendExportRequest(byte[] buffer, int conten
                         status = new Status(StatusCode.Internal, "Failed to deserialize response message.");
                     }
 
-                    OpenTelemetryProtocolExporterEventSource.Log.ResponseDeserializationFailed(this.Endpoint.ToString());
+                    OpenTelemetryProtocolExporterEventSource.Log.ResponseDeserializationFailed(this.Endpoint);
 
                     return new ExportClientGrpcResponse(
                         success: false,
@@ -88,7 +88,7 @@ public override ExportClientResponse SendExportRequest(byte[] buffer, int conten
 
             if (status.StatusCode == StatusCode.OK)
             {
-                OpenTelemetryProtocolExporterEventSource.Log.ExportSuccess(this.Endpoint.ToString(), "Export completed successfully.");
+                OpenTelemetryProtocolExporterEventSource.Log.ExportSuccess(this.Endpoint, "Export completed successfully.");
                 return SuccessExportResponse;
             }
 

src/OpenTelemetry.Exporter.OpenTelemetryProtocol/Implementation/ExportClient/OtlpHttpExportClient.cs

@@ -39,6 +39,7 @@ public override ExportClientResponse SendExportRequest(byte[] buffer, int conten
                 return new ExportClientHttpResponse(success: false, deadlineUtc: deadlineUtc, response: httpResponse, ex);
             }
 
+            OpenTelemetryProtocolExporterEventSource.Log.ExportSuccess(this.Endpoint, "Export completed successfully.");
             return SuccessExportResponse;
         }
         catch (HttpRequestException ex)

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

@@ -104,6 +104,24 @@ public void ExportFailure(Uri endpoint, string message, Status status)
         }
     }
 
+    [NonEvent]
+    public void ExportSuccess(Uri endpoint, string message)
+    {
+        if (Log.IsEnabled(EventLevel.Informational, EventKeywords.All))
+        {
+            this.ExportSuccess(endpoint.ToString(), message);
+        }
+    }
+
+    [NonEvent]
+    public void ResponseDeserializationFailed(Uri endpoint)
+    {
+        if (Log.IsEnabled(EventLevel.Error, EventKeywords.All))
+        {
+            this.ResponseDeserializationFailed(endpoint.ToString());
+        }
+    }
+
     [Event(2, Message = "Exporter failed send data to collector to {0} endpoint. Data will not be sent. Exception: {1}", Level = EventLevel.Error)]
     public void FailedToReachCollector(string rawCollectorUri, string ex)
     {