Improve span naming when serving a resource (Wicket) (open-telemetry#18312)

Co-authored-by: Trask Stalnaker <trask.stalnaker@gmail.com>

Author: asvanberg

instrumentation/wicket-8.0/common-testing/src/main/java/hello/HelloApplication.java

@@ -20,6 +20,7 @@ protected void init() {
     super.init();
 
     mountPage("/exception", ExceptionPage.class);
+    mountResource("/resource", new HelloResource());
   }
 
   @Override

instrumentation/wicket-8.0/common-testing/src/main/java/hello/HelloResource.java

@@ -0,0 +1,23 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package hello;
+
+import org.apache.wicket.request.resource.CharSequenceResource;
+import org.apache.wicket.request.resource.IResource;
+import org.apache.wicket.request.resource.ResourceReference;
+
+public class HelloResource extends ResourceReference {
+  private static final long serialVersionUID = 1L;
+
+  public HelloResource() {
+    super("hello-resource");
+  }
+
+  @Override
+  public IResource getResource() {
+    return new CharSequenceResource("text/plain", "hello resource");
+  }
+}

instrumentation/wicket-8.0/common-testing/src/main/java/io/opentelemetry/javaagent/instrumentation/wicket/v8_0/AbstractWicketTest.java

@@ -76,4 +76,21 @@ void testException() {
                         .hasStatus(StatusData.error())
                         .hasException(new Exception("test exception"))));
   }
+
+  @Test
+  void testResource() {
+    AggregatedHttpResponse response =
+        client.get(address.resolve("wicket-test/resource").toString()).aggregate().join();
+
+    assertThat(response.status().code()).isEqualTo(200);
+    assertThat(response.contentUtf8()).isEqualTo("hello resource");
+
+    testing.waitAndAssertTraces(
+        trace ->
+            trace.hasSpansSatisfyingExactly(
+                span ->
+                    span.hasName("GET " + getContextPath() + "/wicket-test/hello.HelloResource")
+                        .hasKind(SpanKind.SERVER)
+                        .hasNoParent()));
+  }
 }

instrumentation/wicket-8.0/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/wicket/v8_0/RequestHandlerExecutorInstrumentation.java

@@ -18,6 +18,7 @@
 import net.bytebuddy.matcher.ElementMatcher;
 import org.apache.wicket.core.request.handler.IPageClassRequestHandler;
 import org.apache.wicket.request.IRequestHandler;
+import org.apache.wicket.request.handler.resource.ResourceReferenceRequestHandler;
 
 class RequestHandlerExecutorInstrumentation implements TypeInstrumentation {
 
@@ -45,6 +46,13 @@ public static void onEnter(@Advice.Argument(0) IRequestHandler handler) {
             WicketServerSpanNaming.getServerSpanName(),
             (IPageClassRequestHandler) handler);
       }
+      if (handler instanceof ResourceReferenceRequestHandler) {
+        HttpServerRoute.update(
+            Java8BytecodeBridge.currentContext(),
+            CONTROLLER,
+            WicketServerSpanNaming.getServerSpanNameResource(),
+            (ResourceReferenceRequestHandler) handler);
+      }
     }
   }
 }

instrumentation/wicket-8.0/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/wicket/v8_0/WicketServerSpanNaming.java

@@ -9,6 +9,7 @@
 import io.opentelemetry.javaagent.bootstrap.servlet.ServletContextPath;
 import org.apache.wicket.core.request.handler.IPageClassRequestHandler;
 import org.apache.wicket.request.cycle.RequestCycle;
+import org.apache.wicket.request.handler.resource.ResourceReferenceRequestHandler;
 
 public class WicketServerSpanNaming {
 
@@ -22,9 +23,24 @@ public class WicketServerSpanNaming {
         return ServletContextPath.prepend(context, filterPath + "/" + pageName);
       };
 
+  private static final HttpServerRouteGetter<ResourceReferenceRequestHandler>
+      serverSpanNameResource =
+          (context, handler) -> {
+            // using class name as page name
+            String resourceName = handler.getResourceReference().getClass().getName();
+            // wicket filter mapping without wildcard, if wicket filter is mapped to /*
+            // this will be an empty string
+            String filterPath = RequestCycle.get().getRequest().getFilterPath();
+            return ServletContextPath.prepend(context, filterPath + "/" + resourceName);
+          };
+
   public static HttpServerRouteGetter<IPageClassRequestHandler> getServerSpanName() {
     return serverSpanName;
   }
 
+  public static HttpServerRouteGetter<ResourceReferenceRequestHandler> getServerSpanNameResource() {
+    return serverSpanNameResource;
+  }
+
   private WicketServerSpanNaming() {}
 }