[HttpClient] Fix missing metric during network failures

src/OpenTelemetry.Instrumentation.Http/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+* Fixed an issue of missing `http.client.duration` metric data in case of
+network failures.
+([#4098](https://github.com/open-telemetry/opentelemetry-dotnet/pull/4098))
+
 ## 1.4.0-rc9.13
 
 Released 2023-Feb-10

src/OpenTelemetry.Instrumentation.Http/Implementation/HttpHandlerMetricsDiagnosticListener.cs

@@ -28,6 +28,7 @@ internal sealed class HttpHandlerMetricsDiagnosticListener : ListenerHandler
         internal const string OnStopEvent = "System.Net.Http.HttpRequestOut.Stop";
 
         private readonly PropertyFetcher<HttpResponseMessage> stopResponseFetcher = new("Response");
+        private readonly PropertyFetcher<HttpRequestMessage> stopRequestFetcher = new("Request");
         private readonly Histogram<double> httpClientDuration;
 
         public HttpHandlerMetricsDiagnosticListener(string name, Meter meter)
@@ -46,14 +47,11 @@ public override void OnEventWritten(string name, object payload)
                 }
 
                 var activity = Activity.Current;
-                if (this.stopResponseFetcher.TryFetch(payload, out HttpResponseMessage response) && response != null)
+                if (this.stopRequestFetcher.TryFetch(payload, out HttpRequestMessage request) && request != null)
                 {
-                    var request = response.RequestMessage;
-
                     TagList tags = default;
                     tags.Add(new KeyValuePair<string, object>(SemanticConventions.AttributeHttpMethod, HttpTagHelper.GetNameForHttpMethod(request.Method)));
                     tags.Add(new KeyValuePair<string, object>(SemanticConventions.AttributeHttpScheme, request.RequestUri.Scheme));
-                    tags.Add(new KeyValuePair<string, object>(SemanticConventions.AttributeHttpStatusCode, (int)response.StatusCode));
                     tags.Add(new KeyValuePair<string, object>(SemanticConventions.AttributeHttpFlavor, HttpTagHelper.GetFlavorTagValueFromProtocolVersion(request.Version)));
                     tags.Add(new KeyValuePair<string, object>(SemanticConventions.AttributeNetPeerName, request.RequestUri.Host));
 
@@ -62,6 +60,11 @@ public override void OnEventWritten(string name, object payload)
                         tags.Add(new KeyValuePair<string, object>(SemanticConventions.AttributeNetPeerPort, request.RequestUri.Port));
                     }
 
+                    if (this.stopResponseFetcher.TryFetch(payload, out HttpResponseMessage response) && response != null)
+                    {
+                        tags.Add(new KeyValuePair<string, object>(SemanticConventions.AttributeHttpStatusCode, (int)response.StatusCode));
+                    }
+
                     // We are relying here on HttpClient library to set duration before writing the stop event.
                     // https://github.com/dotnet/runtime/blob/90603686d314147017c8bbe1fa8965776ce607d0/src/libraries/System.Net.Http/src/System/Net/Http/DiagnosticsHandler.cs#L178
                     // TODO: Follow up with .NET team if we can continue to rely on this behavior.

test/OpenTelemetry.Instrumentation.Http.Tests/HttpClientTests.cs

@@ -157,58 +157,59 @@ public async Task HttpOutCallsAreCollectedSuccessfullyAsync(HttpTestData.HttpOut
                 Assert.True(enrichWithExceptionCalled);
             }
 
-            if (tc.ResponseExpected)
-            {
 #if NETFRAMEWORK
-                Assert.Empty(requestMetrics);
+            Assert.Empty(requestMetrics);
 #else
-                Assert.Single(requestMetrics);
+            Assert.Single(requestMetrics);
 
-                var metric = requestMetrics[0];
-                Assert.NotNull(metric);
-                Assert.True(metric.MetricType == MetricType.Histogram);
+            var metric = requestMetrics[0];
+            Assert.NotNull(metric);
+            Assert.True(metric.MetricType == MetricType.Histogram);
 
-                var metricPoints = new List<MetricPoint>();
-                foreach (var p in metric.GetMetricPoints())
-                {
-                    metricPoints.Add(p);
-                }
+            var metricPoints = new List<MetricPoint>();
+            foreach (var p in metric.GetMetricPoints())
+            {
+                metricPoints.Add(p);
+            }
 
-                Assert.Single(metricPoints);
-                var metricPoint = metricPoints[0];
+            Assert.Single(metricPoints);
+            var metricPoint = metricPoints[0];
 
-                var count = metricPoint.GetHistogramCount();
-                var sum = metricPoint.GetHistogramSum();
+            var count = metricPoint.GetHistogramCount();
+            var sum = metricPoint.GetHistogramSum();
 
-                Assert.Equal(1L, count);
-                Assert.Equal(activity.Duration.TotalMilliseconds, sum);
+            Assert.Equal(1L, count);
+            Assert.Equal(activity.Duration.TotalMilliseconds, sum);
 
-                var attributes = new KeyValuePair<string, object>[metricPoint.Tags.Count];
-                int i = 0;
-                foreach (var tag in metricPoint.Tags)
-                {
-                    attributes[i++] = tag;
-                }
+            var attributes = new KeyValuePair<string, object>[metricPoint.Tags.Count];
+            int i = 0;
+            foreach (var tag in metricPoint.Tags)
+            {
+                attributes[i++] = tag;
+            }
 
-                var method = new KeyValuePair<string, object>(SemanticConventions.AttributeHttpMethod, tc.Method);
-                var scheme = new KeyValuePair<string, object>(SemanticConventions.AttributeHttpScheme, "http");
-                var statusCode = new KeyValuePair<string, object>(SemanticConventions.AttributeHttpStatusCode, tc.ResponseCode == 0 ? 200 : tc.ResponseCode);
-                var flavor = new KeyValuePair<string, object>(SemanticConventions.AttributeHttpFlavor, "2.0");
-                var hostName = new KeyValuePair<string, object>(SemanticConventions.AttributeNetPeerName, host);
-                var portNumber = new KeyValuePair<string, object>(SemanticConventions.AttributeNetPeerPort, port);
-                Assert.Contains(method, attributes);
-                Assert.Contains(scheme, attributes);
+            var method = new KeyValuePair<string, object>(SemanticConventions.AttributeHttpMethod, tc.Method);
+            var scheme = new KeyValuePair<string, object>(SemanticConventions.AttributeHttpScheme, "http");
+            var statusCode = new KeyValuePair<string, object>(SemanticConventions.AttributeHttpStatusCode, tc.ResponseCode == 0 ? 200 : tc.ResponseCode);
+            var flavor = new KeyValuePair<string, object>(SemanticConventions.AttributeHttpFlavor, "2.0");
+            var hostName = new KeyValuePair<string, object>(SemanticConventions.AttributeNetPeerName, tc.ResponseExpected ? host : "sdlfaldfjalkdfjlkajdflkajlsdjf");
+            var portNumber = new KeyValuePair<string, object>(SemanticConventions.AttributeNetPeerPort, port);
+            Assert.Contains(hostName, attributes);
+            Assert.Contains(portNumber, attributes);
+            Assert.Contains(method, attributes);
+            Assert.Contains(scheme, attributes);
+            Assert.Contains(flavor, attributes);
+            if (tc.ResponseExpected)
+            {
                 Assert.Contains(statusCode, attributes);
-                Assert.Contains(flavor, attributes);
-                Assert.Contains(hostName, attributes);
-                Assert.Contains(portNumber, attributes);
                 Assert.Equal(6, attributes.Length);
-#endif
             }
             else
             {
-                Assert.Empty(requestMetrics);
+                Assert.DoesNotContain(statusCode, attributes);
+                Assert.Equal(5, attributes.Length);
             }
+#endif
         }
 
         [Fact]

test/OpenTelemetry.Instrumentation.Http.Tests/http-out-test-cases.json

@@ -90,35 +90,37 @@
   {
     "name": "Call that cannot resolve DNS will be reported as error span",
     "method": "GET",
-    "url": "https://sdlfaldfjalkdfjlkajdflkajlsdjf.sdlkjafsdjfalfadslkf.com/",
+    "url": "http://sdlfaldfjalkdfjlkajdflkajlsdjf:{port}/",
     "spanName": "HTTP GET",
     "spanStatus": "Error",
     "spanStatusHasDescription": true,
     "responseExpected": false,
     "recordException": false,
     "spanAttributes": {
-      "http.scheme": "https",
+      "http.scheme": "http",
       "http.method": "GET",
-      "net.peer.name": "sdlfaldfjalkdfjlkajdflkajlsdjf.sdlkjafsdjfalfadslkf.com",
+      "net.peer.name": "sdlfaldfjalkdfjlkajdflkajlsdjf",
+      "net.peer.port": "{port}",
       "http.flavor": "{flavor}",
-      "http.url": "https://sdlfaldfjalkdfjlkajdflkajlsdjf.sdlkjafsdjfalfadslkf.com/"
+      "http.url": "http://sdlfaldfjalkdfjlkajdflkajlsdjf:{port}/"
     }
   },
   {
     "name": "Call that cannot resolve DNS will be reported as error span. And Records exception",
     "method": "GET",
-    "url": "https://sdlfaldfjalkdfjlkajdflkajlsdjf.sdlkjafsdjfalfadslkf.com/",
+    "url": "http://sdlfaldfjalkdfjlkajdflkajlsdjf:{port}/",
     "spanName": "HTTP GET",
     "spanStatus": "Error",
     "spanStatusHasDescription": true,
     "responseExpected": false,
     "recordException": true,
     "spanAttributes": {
-      "http.scheme": "https",
+      "http.scheme": "http",
       "http.method": "GET",
-      "net.peer.name": "sdlfaldfjalkdfjlkajdflkajlsdjf.sdlkjafsdjfalfadslkf.com",
+      "net.peer.name": "sdlfaldfjalkdfjlkajdflkajlsdjf",
+      "net.peer.port": "{port}",
       "http.flavor": "{flavor}",
-      "http.url": "https://sdlfaldfjalkdfjlkajdflkajlsdjf.sdlkjafsdjfalfadslkf.com/"
+      "http.url": "http://sdlfaldfjalkdfjlkajdflkajlsdjf:{port}/"
     }
   },
   {