Use StringBuilder to create error message.

Author: hjgraca

libraries/src/AWS.Lambda.Powertools.Tracing/Internal/TracingAspectHandler.cs

@@ -14,6 +14,7 @@
  */
 
 using System;
+using System.Text;
 using AWS.Lambda.Powertools.Common;
 
 namespace AWS.Lambda.Powertools.Tracing.Internal;
@@ -164,24 +165,25 @@ public T OnException<T>(AspectEventArgs eventArgs, Exception exception)
         {
             var nameSpace = GetNamespace();
 
-            var message =
-                "Exception type " + exception.GetType() + Environment.NewLine +
-                "Exception message: " + exception.Message + Environment.NewLine +
-                "Stack trace: " + exception.StackTrace + Environment.NewLine;
+            var sb = new StringBuilder();
+            sb.AppendLine($"Exception type: {exception.GetType()}");
+            sb.AppendLine($"Exception message: {exception.Message}");
+            sb.AppendLine($"Stack trace: {exception.StackTrace}");
+
             if (exception.InnerException != null)
             {
-                message += "---BEGIN InnerException--- " + Environment.NewLine +
-                           "Exception type " + exception.InnerException.GetType() + Environment.NewLine +
-                           "Exception message: " + exception.InnerException.Message + Environment.NewLine +
-                           "Stack trace: " + exception.InnerException.StackTrace + Environment.NewLine +
-                           "---END Inner Exception";
+                sb.AppendLine("---BEGIN InnerException--- ");
+                sb.AppendLine($"Exception type {exception.InnerException.GetType()}");
+                sb.AppendLine($"Exception message: {exception.InnerException.Message}");
+                sb.AppendLine($"Stack trace: {exception.InnerException.StackTrace}");
+                sb.AppendLine("---END Inner Exception");
             }
 
             _xRayRecorder.AddMetadata
             (
                 nameSpace,
                 $"{eventArgs.Name} error",
-                message
+                sb.ToString()
             );
         }
 

libraries/tests/AWS.Lambda.Powertools.Tracing.Tests/TracingAttributeTest.cs

@@ -15,6 +15,7 @@
 
 using System;
 using System.Linq;
+using System.Text;
 using AWS.Lambda.Powertools.Common;
 using AWS.Lambda.Powertools.Tracing.Internal;
 using Moq;
@@ -768,19 +769,20 @@ public void OnException_WhenTracerCaptureModeIsDisabled_DoesNotCaptureError()
 
         static string GetException(Exception exception)
         {
-            var message =
-                "Exception type " + exception.GetType() + Environment.NewLine +
-                "Exception message: " + exception.Message + Environment.NewLine +
-                "Stack trace: " + exception.StackTrace + Environment.NewLine;
+            var sb = new StringBuilder();
+            sb.AppendLine($"Exception type: {exception.GetType()}");
+            sb.AppendLine($"Exception message: {exception.Message}");
+            sb.AppendLine($"Stack trace: {exception.StackTrace}");
+
             if (exception.InnerException != null)
             {
-                message += "---BEGIN InnerException--- " + Environment.NewLine +
-                           "Exception type " + exception.InnerException.GetType() + Environment.NewLine +
-                           "Exception message: " + exception.InnerException.Message + Environment.NewLine +
-                           "Stack trace: " + exception.InnerException.StackTrace + Environment.NewLine +
-                           "---END Inner Exception";
+                sb.AppendLine("---BEGIN InnerException--- ");
+                sb.AppendLine($"Exception type {exception.InnerException.GetType()}");
+                sb.AppendLine($"Exception message: {exception.InnerException.Message}");
+                sb.AppendLine($"Stack trace: {exception.InnerException.StackTrace}");
+                sb.AppendLine("---END Inner Exception");
             }
-            return message;
+            return sb.ToString();
         }
 
         #endregion