Tracing performance optimization.

tests/functional/context-propagation/src/main/java/io/helidon/tests/functional/context/hello/HelloBean.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2020 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -25,7 +25,6 @@
 import io.helidon.common.context.Context;
 import io.helidon.common.context.Contexts;
 
-import io.opentracing.SpanContext;
 import org.eclipse.microprofile.faulttolerance.Asynchronous;
 import org.eclipse.microprofile.faulttolerance.Timeout;
 
@@ -44,7 +43,7 @@ public class HelloBean {
     public String getHello() {
         Context context = Contexts.context().get();
         Objects.requireNonNull(context);
-        Objects.requireNonNull(context.get(SpanContext.class).get());
+
         return "Hello World";
     }
 
@@ -57,7 +56,8 @@ public String getHello() {
     public String getHelloTimeout() {
         Context context = Contexts.context().get();
         Objects.requireNonNull(context);
-        Objects.requireNonNull(context.get(SpanContext.class).get());
+        // span context may be null if tracer is not configured
+        //Objects.requireNonNull(context.get(SpanContext.class).get());
         return "Hello World";
     }
 
@@ -70,7 +70,7 @@ public String getHelloTimeout() {
     public CompletionStage<String> getHelloAsync() {
         Context context = Contexts.context().get();
         Objects.requireNonNull(context);
-        Objects.requireNonNull(context.get(SpanContext.class).get());
+        //Objects.requireNonNull(context.get(SpanContext.class).get());
         return CompletableFuture.completedFuture("Hello World");
     }
 }

tests/functional/context-propagation/src/main/java/io/helidon/tests/functional/context/hello/HelloResource.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2020 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.

tests/functional/context-propagation/src/test/java/io/helidon/tests/functional/context/hello/HelloTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2020 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -55,19 +55,19 @@ static void destroyClass() {
     }
 
     @Test
-    void TestHello() {
+    void testHello() {
         WebTarget target = baseTarget.path("/hello");
         assertOk(target.request().get(), "Hello World");
     }
 
     @Test
-    void TestHelloTimeout() {
+    void testHelloTimeout() {
         WebTarget target = baseTarget.path("/helloTimeout");
         assertOk(target.request().get(), "Hello World");
     }
 
     @Test
-    void TestHelloAsync() {
+    void testHelloAsync() {
         WebTarget target = baseTarget.path("/helloAsync");
         assertOk(target.request().get(), "Hello World");
     }

webserver/jersey/src/test/java/io/helidon/webserver/jersey/JerseyExampleResource.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, 2019 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2017, 2020 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -71,7 +71,8 @@ public class JerseyExampleResource {
     public Response webServerInjection() {
         return Response.ok("request=" + request.getClass().getName()
                                    + "\nresponse=" + response.getClass().getName()
-                                   + "\nspanContext=" + spanContext.getClass().getName()).build();
+                                   + "\nspanContext=" + (null == spanContext ? null : spanContext.getClass().getName()))
+                .build();
     }
 
     @GET

webserver/jersey/src/test/java/io/helidon/webserver/jersey/JerseySupportTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, 2019 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2017, 2020 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -54,9 +54,6 @@ public class JerseySupportTest {
     public static void startServerAndClient() throws Exception {
         JerseyExampleMain.INSTANCE.webServer(true);
         webTarget = JerseyExampleMain.INSTANCE.target();
-
-        //        JerseyGrizzlyRiMain.main(null);
-        //        webTarget = JerseyExampleMain.client().target("http://localhost:8080");
     }
 
     @Test
@@ -76,7 +73,7 @@ public void injection() throws Exception {
         doAssert(response,
                  "request=io.helidon.webserver.RequestRouting$RoutedRequest\n"
                          + "response=io.helidon.webserver.RequestRouting$RoutedResponse\n"
-                         + "spanContext=io.opentracing.noop.NoopSpanContextImpl");
+                         + "spanContext=null");
     }
 
     @Test

webserver/webserver/src/main/java/io/helidon/webserver/WebTracingConfig.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2020 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -20,6 +20,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.stream.Collectors;
 
 import io.helidon.common.context.Context;
@@ -33,6 +34,7 @@
 import io.opentracing.Span;
 import io.opentracing.SpanContext;
 import io.opentracing.Tracer;
+import io.opentracing.noop.NoopScopeManager;
 import io.opentracing.noop.NoopSpanBuilder;
 import io.opentracing.propagation.Format;
 import io.opentracing.propagation.TextMapAdapter;
@@ -224,13 +226,24 @@ public void accept(ServerRequest req, ServerResponse res) {
 
     static final class RequestSpanHandler implements Handler {
         private static final String TRACING_SPAN_HTTP_REQUEST = "HTTP Request";
+        private final AtomicBoolean checkedIfShouldTrace = new AtomicBoolean();
+        private volatile boolean shouldTrace = true;
 
         RequestSpanHandler() {
         }
 
         @Override
         public void accept(ServerRequest req, ServerResponse res) {
-            doAccept(req, res);
+            if (checkedIfShouldTrace.compareAndSet(false, true)) {
+                if (req.tracer().scopeManager() instanceof NoopScopeManager) {
+                    shouldTrace = false;
+                }
+            }
+
+            if (shouldTrace) {
+                doAccept(req, res);
+            }
+
             req.next();
         }
 
@@ -257,22 +270,6 @@ private void doAccept(ServerRequest req, ServerResponse res) {
             SpanContext inboundSpanContext = tracer.extract(Format.Builtin.HTTP_HEADERS, new TextMapAdapter(headersMap));
 
             if (inboundSpanContext instanceof NoopSpanBuilder) {
-                // this is all a noop stuff, does not matter what I do here - this is to prevent null pointers
-                // when span is used
-                // TODO once we return Optional from ServerRequest.spanContext(), we can also remove the
-                // following codeblock and we do not need to create teh span and register it with context
-                Span span = tracer.buildSpan("helidon-webserver")
-                        .asChildOf(inboundSpanContext)
-                        .start();
-
-                context.register(span);
-                context.register(span.context());
-                context.register(ServerRequest.class, span);
-                context.register(ServerRequest.class, span.context());
-
-                res.whenSent()
-                        .thenRun(span::finish);
-
                 // no tracing
                 return;
             }
@@ -304,9 +301,6 @@ private void doAccept(ServerRequest req, ServerResponse res) {
             // cannot use startActive, as it conflicts with the thread model we use
             Span span = spanBuilder.start();
 
-            // TODO remove the next single line for version 2.0 - we should only expose SpanContext
-            context.register(span);
-            context.register(ServerRequest.class, span);
             context.register(span.context());
             context.register(ServerRequest.class, span.context());