Enable enrich for HttpWebRequest

src/OpenTelemetry.Instrumentation.Http/CHANGELOG.md

@@ -2,6 +2,11 @@
 
 ## Unreleased
 
+* Instrumentation no longer store raw objects like `HttpWebRequest` in
+  Activity.CustomProperty. To enrich activity, use the Enrich action on the
+  instrumentation.
+  ([#1261](https://github.com/open-telemetry/opentelemetry-dotnet/pull/1407))
+
 ## 0.7.0-beta.1
 
 Released 2020-Oct-16

src/OpenTelemetry.Instrumentation.Http/HttpWebRequestInstrumentationOptions.netfx.cs

@@ -16,6 +16,7 @@
 
 #if NETFRAMEWORK
 using System;
+using System.Diagnostics;
 using System.Net;
 using OpenTelemetry.Context.Propagation;
 using OpenTelemetry.Instrumentation.Http.Implementation;
@@ -50,6 +51,17 @@ public class HttpWebRequestInstrumentationOptions
         /// </summary>
         public Func<HttpWebRequest, bool> Filter { get; set; }
 
+        /// <summary>
+        /// Gets or sets an action to enrich an Activity.
+        /// </summary>
+        /// <remarks>
+        /// <para><see cref="Activity"/>: the activity being enriched.</para>
+        /// <para>string: the name of the event.</para>
+        /// <para>object: the raw object from which additional information can be extracted to enrich the activity.
+        /// The type of this object depends on the event, which is given by the above parameter.</para>
+        /// </remarks>
+        public Action<Activity, string, object> Enrich { get; set; }
+
         internal bool EventFilter(HttpWebRequest request)
         {
             try

src/OpenTelemetry.Instrumentation.Http/Implementation/HttpWebRequestActivitySource.netfx.cs

@@ -22,8 +22,6 @@
 using System.Reflection;
 using System.Reflection.Emit;
 using System.Runtime.CompilerServices;
-using System.Text;
-using OpenTelemetry.Context;
 using OpenTelemetry.Context.Propagation;
 using OpenTelemetry.Trace;
 
@@ -41,10 +39,6 @@ internal static class HttpWebRequestActivitySource
         public const string ActivitySourceName = "OpenTelemetry.HttpWebRequest";
         public const string ActivityName = ActivitySourceName + ".HttpRequestOut";
 
-        public const string RequestCustomPropertyName = "OTel.HttpWebRequest.Request";
-        public const string ResponseCustomPropertyName = "OTel.HttpWebRequest.Response";
-        public const string ExceptionCustomPropertyName = "OTel.HttpWebRequest.Exception";
-
         internal static readonly Func<HttpWebRequest, string, IEnumerable<string>> HttpWebRequestHeaderValuesGetter = (request, name) => request.Headers.GetValues(name);
         internal static readonly Action<HttpWebRequest, string, string> HttpWebRequestHeaderValuesSetter = (request, name, value) => request.Headers.Add(name, value);
 
@@ -104,7 +98,15 @@ private static void AddRequestTagsAndInstrumentRequest(HttpWebRequest request, A
 
             if (activity.IsAllDataRequested)
             {
-                activity.SetCustomProperty(RequestCustomPropertyName, request);
+                try
+                {
+                    Options.Enrich?.Invoke(activity, "AddRequestTagsAndInstrumentRequest", request);
+                }
+                catch (Exception ex)
+                {
+                    HttpInstrumentationEventSource.Log.EnrichmentException(ex);
+                }
+
                 activity.SetTag(SemanticConventions.AttributeHttpMethod, request.Method);
                 activity.SetTag(SemanticConventions.AttributeHttpHost, HttpTagHelper.GetHostTagValueFromRequestUri(request.RequestUri));
                 activity.SetTag(SemanticConventions.AttributeHttpUrl, request.RequestUri.OriginalString);
@@ -120,7 +122,15 @@ private static void AddResponseTags(HttpWebResponse response, Activity activity)
         {
             if (activity.IsAllDataRequested)
             {
-                activity.SetCustomProperty(ResponseCustomPropertyName, response);
+                try
+                {
+                    Options.Enrich?.Invoke(activity, "AddResponseTags", response);
+                }
+                catch (Exception ex)
+                {
+                    HttpInstrumentationEventSource.Log.EnrichmentException(ex);
+                }
+
                 activity.SetTag(SemanticConventions.AttributeHttpStatusCode, (int)response.StatusCode);
 
                 activity.SetStatus(
@@ -138,7 +148,14 @@ private static void AddExceptionTags(Exception exception, Activity activity)
                 return;
             }
 
-            activity.SetCustomProperty(ExceptionCustomPropertyName, exception);
+            try
+            {
+                Options.Enrich?.Invoke(activity, "AddExceptionTags", exception);
+            }
+            catch (Exception ex)
+            {
+                HttpInstrumentationEventSource.Log.EnrichmentException(ex);
+            }
 
             Status status;
             if (exception is WebException wexc)