Add javaagent<->application context bridge for HttpRouteHolder (#5838)

* Add javaagent<->application context bridge for HttpRouteHolder

* remove comments

* fix broken http.route bridge

* spotless

* Move to a separate module

instrumentation-api-semconv/src/main/java/io/opentelemetry/instrumentation/api/instrumenter/http/HttpRouteHolder.java

@@ -7,10 +7,10 @@
 
 import io.opentelemetry.api.trace.Span;
 import io.opentelemetry.context.Context;
-import io.opentelemetry.context.ContextKey;
 import io.opentelemetry.instrumentation.api.instrumenter.ContextCustomizer;
 import io.opentelemetry.instrumentation.api.instrumenter.Instrumenter;
 import io.opentelemetry.instrumentation.api.instrumenter.LocalRootSpan;
+import io.opentelemetry.instrumentation.api.internal.HttpRouteState;
 import io.opentelemetry.semconv.trace.attributes.SemanticAttributes;
 import javax.annotation.Nullable;
 
@@ -25,25 +25,19 @@
  */
 public final class HttpRouteHolder {
 
- private static final ContextKey<HttpRouteHolder> CONTEXT_KEY =
- ContextKey.named("opentelemetry-http-server-route-key");
-
  /**
  * Returns a {@link ContextCustomizer} that initializes a {@link HttpRouteHolder} in the {@link
  * Context} returned from {@link Instrumenter#start(Context, Object)}.
  */
  public static <REQUEST> ContextCustomizer<REQUEST> get() {
  return (context, request, startAttributes) -> {
- if (context.get(CONTEXT_KEY) != null) {
+ if (HttpRouteState.fromContextOrNull(context) != null) {
  return context;
  }
- return context.with(CONTEXT_KEY, new HttpRouteHolder());
+ return context.with(HttpRouteState.create(0, null));
  };
  }
 
- private volatile int updatedBySourceOrder = 0;
- @Nullable private volatile String route;
-
  private HttpRouteHolder() {}
 
  /**
@@ -107,8 +101,8 @@ public static <T, U> void updateHttpRoute(
  if (serverSpan == null) {
  return;
  }
- HttpRouteHolder httpRouteHolder = context.get(CONTEXT_KEY);
- if (httpRouteHolder == null) {
+ HttpRouteState httpRouteState = HttpRouteState.fromContextOrNull(context);
+ if (httpRouteState == null) {
  String httpRoute = httpRouteGetter.get(context, arg1, arg2);
  if (httpRoute != null && !httpRoute.isEmpty()) {
  // update both span name and attribute, since there's no HttpRouteHolder in the context
@@ -120,27 +114,26 @@ public static <T, U> void updateHttpRoute(
  // special case for servlet filters, even when we have a route from previous filter see whether
  // the new route is better and if so use it instead
  boolean onlyIfBetterRoute =
- !source.useFirst && source.order == httpRouteHolder.updatedBySourceOrder;
- if (source.order > httpRouteHolder.updatedBySourceOrder || onlyIfBetterRoute) {
+ !source.useFirst && source.order == httpRouteState.getUpdatedBySourceOrder();
+ if (source.order > httpRouteState.getUpdatedBySourceOrder() || onlyIfBetterRoute) {
  String route = httpRouteGetter.get(context, arg1, arg2);
  if (route != null
  && !route.isEmpty()
- && (!onlyIfBetterRoute || httpRouteHolder.isBetterRoute(route))) {
+ && (!onlyIfBetterRoute || isBetterRoute(httpRouteState, route))) {
 
  // update just the span name - the attribute will be picked up by the
  // HttpServerAttributesExtractor at the end of request processing
  serverSpan.updateName(route);
 
- httpRouteHolder.updatedBySourceOrder = source.order;
- httpRouteHolder.route = route;
+ httpRouteState.update(context, source.order, route);
  }
  }
  }
 
  // This is used when setting route from a servlet filter to pick the most descriptive (longest)
  // route.
- private boolean isBetterRoute(String name) {
- String route = this.route;
+ private static boolean isBetterRoute(HttpRouteState httpRouteState, String name) {
+ String route = httpRouteState.getRoute();
  int routeLength = route == null ? 0 : route.length();
  return name.length() > routeLength;
  }
@@ -151,8 +144,8 @@ private boolean isBetterRoute(String name) {
  */
  @Nullable
  static String getRoute(Context context) {
- HttpRouteHolder httpRouteHolder = context.get(CONTEXT_KEY);
- return httpRouteHolder == null ? null : httpRouteHolder.route;
+ HttpRouteState httpRouteState = HttpRouteState.fromContextOrNull(context);
+ return httpRouteState == null ? null : httpRouteState.getRoute();
  }
 
  private static final class OneArgAdapter<T> implements HttpRouteBiGetter<T, HttpRouteGetter<T>> {

instrumentation-api-semconv/src/main/java/io/opentelemetry/instrumentation/api/internal/HttpRouteState.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.instrumentation.api.internal;
+
+import io.opentelemetry.context.Context;
+import io.opentelemetry.context.ContextKey;
+import io.opentelemetry.context.ImplicitContextKeyed;
+import javax.annotation.Nullable;
+
+/**
+ * This class is internal and is hence not for public use. Its APIs are unstable and can change at
+ * any time.
+ */
+public final class HttpRouteState implements ImplicitContextKeyed {
+
+ private static final ContextKey<HttpRouteState> KEY =
+ ContextKey.named("opentelemetry-http-server-route-key");
+
+ @Nullable
+ public static HttpRouteState fromContextOrNull(Context context) {
+ return context.get(KEY);
+ }
+
+ public static HttpRouteState create(int updatedBySourceOrder, @Nullable String route) {
+ return new HttpRouteState(updatedBySourceOrder, route);
+ }
+
+ private volatile int updatedBySourceOrder;
+ @Nullable private volatile String route;
+
+ private HttpRouteState(int updatedBySourceOrder, @Nullable String route) {
+ this.updatedBySourceOrder = updatedBySourceOrder;
+ this.route = route;
+ }
+
+ @Override
+ public Context storeInContext(Context context) {
+ return context.with(KEY, this);
+ }
+
+ public int getUpdatedBySourceOrder() {
+ return updatedBySourceOrder;
+ }
+
+ @Nullable
+ public String getRoute() {
+ return route;
+ }
+
+ public void update(
+ @SuppressWarnings("unused")
+ Context context, // context is used by the javaagent bridge instrumentation
+ int updatedBySourceOrder,
+ String route) {
+ this.updatedBySourceOrder = updatedBySourceOrder;
+ this.route = route;
+ }
+}

instrumentation/opentelemetry-api/opentelemetry-api-1.0/javaagent/build.gradle.kts

@@ -42,39 +42,4 @@ dependencies {
  // @WithSpan annotation is used to generate spans in ContextBridgeTest
  testImplementation("io.opentelemetry:opentelemetry-extension-annotations")
  testInstrumentation(project(":instrumentation:opentelemetry-annotations-1.0:javaagent"))
-
- testImplementation(project(":instrumentation:opentelemetry-api:opentelemetry-api-1.0:testing"))
- testInstrumentation(project(":instrumentation:opentelemetry-api:opentelemetry-api-1.0:testing"))
-}
-
-testing {
- suites {
- val testOldInstrumentationApi by registering(JvmTestSuite::class) {
- dependencies {
- implementation("io.opentelemetry.instrumentation:opentelemetry-instrumentation-api-semconv")
- implementation("io.opentelemetry.instrumentation:opentelemetry-instrumentation-api")
- implementation(project(":instrumentation:opentelemetry-api:opentelemetry-api-1.0:testing"))
- }
- }
- }
-}
-
-configurations.configureEach {
- if (name.contains("testOldInstrumentationApi")) {
- resolutionStrategy {
- dependencySubstitution {
- // version 1.13.0 contains the old ServerSpan implementation that uses SERVER_KEY context key
- substitute(module("io.opentelemetry.instrumentation:opentelemetry-instrumentation-api-semconv"))
- .using(module("io.opentelemetry.instrumentation:opentelemetry-instrumentation-api-semconv:1.13.0-alpha"))
- substitute(module("io.opentelemetry.instrumentation:opentelemetry-instrumentation-api"))
- .using(module("io.opentelemetry.instrumentation:opentelemetry-instrumentation-api:1.13.0-alpha"))
- }
- }
- }
-}
-
-tasks {
- check {
- dependsOn(testing.suites)
- }
 }