Fix http.route tracing attribute reporting

We know properly report the root path
whereas previously it was being ignored

Fixes: #34778

extensions/opentelemetry/deployment/pom.xml

@@ -86,6 +86,11 @@
             <artifactId>vertx-web-client</artifactId>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>io.quarkus</groupId>
+            <artifactId>quarkus-reactive-routes-deployment</artifactId>
+            <scope>test</scope>
+        </dependency>
         <dependency>
             <groupId>io.quarkus</groupId>
             <artifactId>quarkus-resteasy-deployment</artifactId>

extensions/opentelemetry/deployment/src/test/java/io/quarkus/opentelemetry/deployment/OpenTelemetryReactiveRoutesTest.java

@@ -0,0 +1,96 @@
+package io.quarkus.opentelemetry.deployment;
+
+import static io.opentelemetry.api.trace.SpanKind.SERVER;
+import static io.quarkus.opentelemetry.deployment.common.TestSpanExporter.getSpanByKindAndParentId;
+import static io.quarkus.opentelemetry.deployment.common.TestUtil.assertStringAttribute;
+import static org.hamcrest.Matchers.is;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import io.quarkus.opentelemetry.deployment.common.TestUtil;
+import java.util.List;
+
+import jakarta.enterprise.context.ApplicationScoped;
+import jakarta.inject.Inject;
+import jakarta.ws.rs.GET;
+
+import org.jboss.shrinkwrap.api.ShrinkWrap;
+import org.jboss.shrinkwrap.api.spec.JavaArchive;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
+
+import io.opentelemetry.sdk.trace.data.SpanData;
+import io.opentelemetry.semconv.trace.attributes.SemanticAttributes;
+import io.quarkus.opentelemetry.deployment.common.TestSpanExporter;
+import io.quarkus.opentelemetry.deployment.common.TestSpanExporterProvider;
+import io.quarkus.test.QuarkusUnitTest;
+import io.quarkus.vertx.web.Route;
+import io.restassured.RestAssured;
+import io.smallrye.config.SmallRyeConfig;
+import io.vertx.ext.web.RoutingContext;
+
+public class OpenTelemetryReactiveRoutesTest {
+    @RegisterExtension
+    static final QuarkusUnitTest TEST = new QuarkusUnitTest().setArchiveProducer(
+            () -> ShrinkWrap.create(JavaArchive.class)
+                    .addClass(TestUtil.class)
+                    .addClass(TestSpanExporter.class)
+                    .addClass(TestSpanExporterProvider.class)
+                    .addAsResource("resource-config/application.properties", "application.properties")
+                    .addAsResource(
+                            "META-INF/services-config/io.opentelemetry.sdk.autoconfigure.spi.traces.ConfigurableSpanExporterProvider",
+                            "META-INF/services/io.opentelemetry.sdk.autoconfigure.spi.traces.ConfigurableSpanExporterProvider"));
+    @Inject
+    TestSpanExporter spanExporter;
+
+    @AfterEach
+    void tearDown() {
+        spanExporter.reset();
+    }
+
+    @Test
+    void root() {
+        RestAssured.when()
+                .get("/").then()
+                .statusCode(200)
+                .body(is("hello"));
+
+        List<SpanData> spans = spanExporter.getFinishedSpanItems(1);
+
+        final SpanData server = getSpanByKindAndParentId(spans, SERVER, "0000000000000000");
+        assertEquals("GET /", server.getName());
+        assertStringAttribute(server, SemanticAttributes.HTTP_ROUTE, "/");
+    }
+
+    @Test
+    void nonRoot() {
+        RestAssured.when()
+                .get("/hello").then()
+                .statusCode(200)
+                .body(is("hello world"));
+
+        List<SpanData> spans = spanExporter.getFinishedSpanItems(1);
+
+        final SpanData server = getSpanByKindAndParentId(spans, SERVER, "0000000000000000");
+        assertEquals("GET /hello", server.getName());
+        assertStringAttribute(server, SemanticAttributes.HTTP_ROUTE, "/hello");
+    }
+
+    @ApplicationScoped
+    public static class Routes {
+
+        @Route(path = "/", methods = Route.HttpMethod.GET)
+        public void root(RoutingContext rc) {
+            rc.response().end("hello");
+        }
+
+        @Route(path = "/hello", methods = Route.HttpMethod.GET)
+        public void hello(RoutingContext rc) {
+            String name = rc.request().getParam("name");
+            if (name == null) {
+                name = "world";
+            }
+            rc.response().end("hello " + name);
+        }
+    }
+}

extensions/opentelemetry/runtime/src/main/java/io/quarkus/opentelemetry/runtime/tracing/intrumentation/vertx/HttpInstrumenterVertxTracer.java

@@ -156,7 +156,7 @@ public String get(final io.opentelemetry.context.Context context, final HttpRequ
                 route = requestSpan.getContext().getLocal("VertxRoute");
             }
 
-            if (route != null && route.length() > 1) {
+            if (route != null && route.length() >= 1) {
                 return route;
             }