User route template as OpenTelemetry HTTP route (#182)

* User route template as OpenTelemetry HTTP route

* Remove unused import

* Verify 404 not found still has route path returned

* Set status code in doOnNext

* Update tracing-opentelemetry-http/src/main/java/io/micronaut/tracing/opentelemetry/instrument/http/server/OpenTelemetryServerFilter.java

Co-authored-by: Nemanja Mikic <n0t_l3ss@outlook.com>

tracing-opentelemetry-http/src/main/java/io/micronaut/tracing/opentelemetry/instrument/http/server/MicronautHttpServerAttributesGetter.java

@@ -25,7 +25,6 @@
 
 import javax.annotation.Nullable;
 import java.util.List;
-import java.util.Optional;
 
 @Internal
 enum MicronautHttpServerAttributesGetter implements HttpServerAttributesGetter<HttpRequest<Object>, HttpResponse<Object>> {
@@ -103,8 +102,9 @@ public String target(HttpRequest<Object> request) {
     @Override
     @Nullable
     public String route(HttpRequest<Object> request) {
-        Optional<Object> routeInfo = request.getAttribute(HttpAttributes.ROUTE_INFO);
-        return routeInfo.map(Object::toString).orElse(null);
+        String route = request.getAttribute(HttpAttributes.URI_TEMPLATE).map(Object::toString)
+            .orElse(request.getUri().toString());
+        return request.getMethodName() + " - " + route;
     }
 
     @Override

tracing-opentelemetry-http/src/main/java/io/micronaut/tracing/opentelemetry/instrument/http/server/OpenTelemetryServerFilter.java

@@ -27,6 +27,8 @@
 import io.micronaut.tracing.opentelemetry.instrument.util.OpenTelemetryExclusionsConfiguration;
 import io.micronaut.tracing.opentelemetry.instrument.util.OpenTelemetryObserver;
 import io.micronaut.tracing.opentelemetry.instrument.util.OpenTelemetryPublisherUtils;
+import io.opentelemetry.api.trace.Span;
+import io.opentelemetry.api.trace.StatusCode;
 import io.opentelemetry.api.trace.Tracer;
 import io.opentelemetry.context.Context;
 import io.opentelemetry.instrumentation.api.instrumenter.Instrumenter;
@@ -82,6 +84,15 @@ public Publisher<MutableHttpResponse<?>> doFilter(HttpRequest<?> request, Server
         Context newContext = instrumenter.start(parentContext, request);
 
         return OpenTelemetryPublisherUtils.createOpenTelemetryPublisher(requestPublisher, instrumenter, newContext, request, new OpenTelemetryObserver<MutableHttpResponse<?>>() {
+
+            @Override
+            public void doOnNext(MutableHttpResponse<?> object, Context context) {
+                OpenTelemetryObserver.super.doOnNext(object, context);
+                if (object.status().getCode() >= 400) {
+                    Span.current().setStatus(StatusCode.ERROR);
+                }
+            }
+
             @Override
             public void doOnError(@NonNull Throwable throwable, @NonNull Context openTelemetryContext) {
                 request.setAttribute(CONTINUE, true);

tracing-opentelemetry-http/src/test/groovy/io/micronaut/tracing/instrument/http/OpenTelemetryHttpSpec.groovy

@@ -234,6 +234,23 @@ class OpenTelemetryHttpSpec extends Specification {
         testExporter.reset()
     }
 
+    void 'test error 404'() {
+        when:
+        def route = '/error/notFoundRoute'
+        HttpResponse<String> response = reactorHttpClient.toBlocking().exchange(route, String)
+
+        then:
+        def e = thrown(HttpClientResponseException)
+        e.message == "Not Found"
+        conditions.eventually {
+            exporter.finishedSpanItems.size() == 1
+            exporter.finishedSpanItems[0].name == "GET - " + route
+            exporter.finishedSpanItems[0].status.statusCode == StatusCode.ERROR
+        }
+        cleanup:
+        exporter.reset()
+    }
+
     @Introspected
     static class SomeBody {
     }