We always set HttpRoute to the same as AspNetCoreRoute, so we can just make it readonly

Author: andrewlock

tracer/src/Datadog.Trace/DiagnosticListeners/AspNetCoreDiagnosticObserver.cs

@@ -404,7 +404,6 @@ private static Span StartMvcCoreSpan(
                 // these will already be set correctly
                 rootSpanTags.AspNetCoreRoute = aspNetRoute;
                 rootSpan.ResourceName = span.ResourceName;
-                rootSpanTags.HttpRoute = aspNetRoute;
             }
 
             return span;
@@ -575,7 +574,6 @@ private void OnRoutingEndpointMatched(object arg)
                 {
                     rootSpan.ResourceName = resourceName;
                     tags.AspNetCoreRoute = normalizedRoute;
-                    tags.HttpRoute = normalizedRoute;
                 }
 
                 _security.CheckPathParamsAndSessionId(httpContext, rootSpan, routeValues);

tracer/src/Datadog.Trace/Generated/net461/Datadog.Trace.SourceGenerators/TagListGenerator/AspNetCoreTags.g.cs

@@ -55,7 +55,7 @@ public override void SetTag(string key, string? value)
                     AspNetCoreRoute = value;
                     break;
                 case "http.route": 
-                    HttpRoute = value;
+                    Logger.Value.Warning("Attempted to set readonly tag {TagName} on {TagType}. Ignoring.", key, nameof(AspNetCoreTags));
                     break;
                 default: 
                     base.SetTag(key, value);

tracer/src/Datadog.Trace/Generated/net6.0/Datadog.Trace.SourceGenerators/TagListGenerator/AspNetCoreTags.g.cs

@@ -55,7 +55,7 @@ public override void SetTag(string key, string? value)
                     AspNetCoreRoute = value;
                     break;
                 case "http.route": 
-                    HttpRoute = value;
+                    Logger.Value.Warning("Attempted to set readonly tag {TagName} on {TagType}. Ignoring.", key, nameof(AspNetCoreTags));
                     break;
                 default: 
                     base.SetTag(key, value);

tracer/src/Datadog.Trace/Generated/netcoreapp3.1/Datadog.Trace.SourceGenerators/TagListGenerator/AspNetCoreTags.g.cs

@@ -55,7 +55,7 @@ public override void SetTag(string key, string? value)
                     AspNetCoreRoute = value;
                     break;
                 case "http.route": 
-                    HttpRoute = value;
+                    Logger.Value.Warning("Attempted to set readonly tag {TagName} on {TagType}. Ignoring.", key, nameof(AspNetCoreTags));
                     break;
                 default: 
                     base.SetTag(key, value);

tracer/src/Datadog.Trace/Generated/netstandard2.0/Datadog.Trace.SourceGenerators/TagListGenerator/AspNetCoreTags.g.cs

@@ -55,7 +55,7 @@ public override void SetTag(string key, string? value)
                     AspNetCoreRoute = value;
                     break;
                 case "http.route": 
-                    HttpRoute = value;
+                    Logger.Value.Warning("Attempted to set readonly tag {TagName} on {TagType}. Ignoring.", key, nameof(AspNetCoreTags));
                     break;
                 default: 
                     base.SetTag(key, value);

tracer/src/Datadog.Trace/Tagging/AspNetCoreTags.cs

@@ -19,6 +19,6 @@ internal partial class AspNetCoreTags : WebTags
         public string AspNetCoreRoute { get; set; }
 
         [Tag(Tags.HttpRoute)]
-        public string HttpRoute { get; set; }
+        public string HttpRoute => AspNetCoreRoute;
     }
 }