extract url template in onStart

Author: laurit

instrumentation-api-incubator/src/main/java/io/opentelemetry/instrumentation/api/incubator/semconv/http/HttpExperimentalAttributesExtractor.java

@@ -48,7 +48,15 @@ private HttpExperimentalAttributesExtractor(
   }
 
   @Override
-  public void onStart(AttributesBuilder attributes, Context parentContext, REQUEST request) {}
+  public void onStart(AttributesBuilder attributes, Context parentContext, REQUEST request) {
+    if (getter instanceof HttpClientAttributesGetter) {
+      HttpClientAttributesGetter<REQUEST, RESPONSE> clientGetter =
+          (HttpClientAttributesGetter<REQUEST, RESPONSE>) getter;
+      String urlTemplate =
+          HttpClientUrlTemplateUtil.getUrlTemplate(parentContext, request, clientGetter);
+      internalSet(attributes, URL_TEMPLATE, urlTemplate);
+    }
+  }
 
   @Override
   public void onEnd(
@@ -65,13 +73,6 @@ public void onEnd(
       Long responseBodySize = responseBodySize(request, response);
       internalSet(attributes, HTTP_RESPONSE_BODY_SIZE, responseBodySize);
     }
-
-    if (getter instanceof HttpClientAttributesGetter) {
-      HttpClientAttributesGetter<REQUEST, RESPONSE> clientGetter =
-          (HttpClientAttributesGetter<REQUEST, RESPONSE>) getter;
-      String urlTemplate = HttpClientUrlTemplateUtil.getUrlTemplate(context, request, clientGetter);
-      internalSet(attributes, URL_TEMPLATE, urlTemplate);
-    }
   }
 
   @Nullable

instrumentation-api-incubator/src/test/java/io/opentelemetry/instrumentation/api/incubator/semconv/http/HttpExperimentalAttributesExtractorTest.java

@@ -60,7 +60,7 @@ void runTest(
 
     AttributesBuilder attributes = Attributes.builder();
     extractor.onStart(attributes, Context.root(), "request");
-    assertThat(attributes.build()).isEmpty();
+    assertThat(attributes.build().asMap()).containsExactlyInAnyOrderEntriesOf(expected);
 
     extractor.onEnd(attributes, Context.root(), "request", "response", null);
     Map<AttributeKey<?>, Object> expectedAttributes = new HashMap<>(expected);