interop: enable OpenTelemetry tracing support in Java interop client …

gradle/libs.versions.toml

@@ -122,6 +122,7 @@ opencensus-impl = { module = "io.opencensus:opencensus-impl", version.ref = "ope
 opentelemetry-api = "io.opentelemetry:opentelemetry-api:1.64.0"
 opentelemetry-exporter-prometheus = "io.opentelemetry:opentelemetry-exporter-prometheus:1.64.0-alpha"
 opentelemetry-gcp-resources = "io.opentelemetry.contrib:opentelemetry-gcp-resources:1.59.0-alpha"
+opentelemetry-exporter-otlp = "io.opentelemetry:opentelemetry-exporter-otlp:1.64.0"
 opentelemetry-sdk-extension-autoconfigure = "io.opentelemetry:opentelemetry-sdk-extension-autoconfigure:1.64.0"
 opentelemetry-sdk-testing = "io.opentelemetry:opentelemetry-sdk-testing:1.64.0"
 perfmark-api = "io.perfmark:perfmark-api:0.27.0"

interop-testing/build.gradle

@@ -26,6 +26,7 @@ dependencies {
             libraries.opencensus.contrib.grpc.metrics,
             libraries.google.auth.oauth2Http,
             libraries.opentelemetry.sdk.extension.autoconfigure,
+            libraries.opentelemetry.exporter.otlp,
             libraries.guava.jre // Fix checkUpperBoundDeps using -android
     api project(':grpc-api'),
             project(':grpc-stub'),

interop-testing/src/main/java/io/grpc/testing/integration/OpenTelemetryUtil.java

@@ -0,0 +1,66 @@
+/*
+ * Copyright 2026 The gRPC Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.grpc.testing.integration;
+
+import io.grpc.opentelemetry.GrpcOpenTelemetry;
+import io.grpc.opentelemetry.InternalGrpcOpenTelemetry;
+import io.opentelemetry.sdk.OpenTelemetrySdk;
+import io.opentelemetry.sdk.autoconfigure.AutoConfiguredOpenTelemetrySdk;
+import io.opentelemetry.sdk.autoconfigure.AutoConfiguredOpenTelemetrySdkBuilder;
+import java.util.HashMap;
+import java.util.Map;
+import org.codehaus.mojo.animal_sniffer.IgnoreJRERequirement;
+
+/**
+ * Utility methods for OpenTelemetry configuration in integration testing.
+ */
+public final class OpenTelemetryUtil {
+
+  private OpenTelemetryUtil() {}
+
+  /**
+   * Initializes and registers OpenTelemetry tracing for interop client and server.
+   *
+   * @param otelCollectorAddress optional collector address (e.g. "localhost:4317")
+   * @return the configured {@link OpenTelemetrySdk}
+   */
+  @IgnoreJRERequirement // OpenTelemetry uses Java 8+ APIs
+  public static OpenTelemetrySdk setupOpenTelemetry(String otelCollectorAddress) {
+    AutoConfiguredOpenTelemetrySdkBuilder sdkBuilder =
+        AutoConfiguredOpenTelemetrySdk.builder();
+    Map<String, String> properties = new HashMap<>();
+    properties.put("otel.traces.exporter", "otlp");
+    // Reduce BatchSpanProcessor export delay from default 5000ms to 100ms for fast test runs.
+    properties.put("otel.bsp.schedule.delay", "100");
+    if (otelCollectorAddress != null && !otelCollectorAddress.isEmpty()) {
+      String endpoint = otelCollectorAddress;
+      if (!endpoint.startsWith("http://") && !endpoint.startsWith("https://")) {
+        endpoint = "http://" + endpoint;
+      }
+      properties.put("otel.exporter.otlp.endpoint", endpoint);
+    }
+    sdkBuilder.addPropertiesSupplier(() -> properties);
+    AutoConfiguredOpenTelemetrySdk autoSdk = sdkBuilder.build();
+    OpenTelemetrySdk openTelemetrySdk = autoSdk.getOpenTelemetrySdk();
+    GrpcOpenTelemetry.Builder grpcOpentelemetryBuilder = GrpcOpenTelemetry.newBuilder()
+        .sdk(openTelemetrySdk);
+    InternalGrpcOpenTelemetry.enableTracing(grpcOpentelemetryBuilder, true);
+    GrpcOpenTelemetry grpcOpenTelemetry = grpcOpentelemetryBuilder.build();
+    grpcOpenTelemetry.registerGlobal();
+    return openTelemetrySdk;
+  }
+}

interop-testing/src/main/java/io/grpc/testing/integration/TestServiceClient.java

@@ -68,6 +68,7 @@
 import io.grpc.testing.integration.Messages.StreamingOutputCallRequest;
 import io.grpc.testing.integration.Messages.StreamingOutputCallResponse;
 import io.grpc.testing.integration.Messages.TestOrcaReport;
+import io.opentelemetry.sdk.OpenTelemetrySdk;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.InputStream;
@@ -79,6 +80,7 @@
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicReference;
 import javax.annotation.Nullable;
+import org.codehaus.mojo.animal_sniffer.IgnoreJRERequirement;
 
 /**
  * Application that starts a client for the {@link TestServiceGrpc.TestServiceImplBase} and runs
@@ -135,6 +137,9 @@ public static void main(String[] args) throws Exception {
   private int soakRequestSize = 271828;
   private int soakResponseSize = 314159;
   private int numThreads = 1;
+  private boolean enableOpentelemetry;
+  private String otelCollectorAddress;
+  private OpenTelemetrySdk openTelemetrySdk;
   private String additionalMetadata = "";
   private static LoadBalancerProvider customBackendMetricsLoadBalancerProvider;
 
@@ -219,6 +224,10 @@ void parseArgs(String[] args) throws Exception {
         numThreads = Integer.parseInt(value);
       } else if ("additional_metadata".equals(key)) {
         additionalMetadata = value;
+      } else if ("enable_opentelemetry".equals(key)) {
+        enableOpentelemetry = Boolean.parseBoolean(value);
+      } else if ("otel_collector_address".equals(key)) {
+        otelCollectorAddress = value;
       } else {
         System.err.println("Unknown argument: " + key);
         usage = true;
@@ -306,7 +315,11 @@ void parseArgs(String[] args) throws Exception {
   }
 
   @VisibleForTesting
+  @IgnoreJRERequirement // OpenTelemetry uses Java 8+ APIs
   void setUp() {
+    if (enableOpentelemetry) {
+      this.openTelemetrySdk = OpenTelemetryUtil.setupOpenTelemetry(otelCollectorAddress);
+    }
     tester.setUp();
   }
 
@@ -321,6 +334,10 @@ private synchronized void tearDown() {
       throw ex;
     } catch (Exception ex) {
       throw new RuntimeException(ex);
+    } finally {
+      if (openTelemetrySdk != null) {
+        openTelemetrySdk.close();
+      }
     }
   }
 

interop-testing/src/main/java/io/grpc/testing/integration/TestServiceServer.java

@@ -32,13 +32,15 @@
 import io.grpc.testing.TlsTesting;
 import io.grpc.xds.orca.OrcaMetricReportingServerInterceptor;
 import io.grpc.xds.orca.OrcaServiceImpl;
+import io.opentelemetry.sdk.OpenTelemetrySdk;
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
 import java.util.List;
 import java.util.Locale;
 import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.TimeUnit;
+import org.codehaus.mojo.animal_sniffer.IgnoreJRERequirement;
 
 /** Server that manages startup/shutdown of a single {@code TestService}. */
 public class TestServiceServer {
@@ -76,6 +78,9 @@ public void run() {
   private boolean useTls = true;
   private boolean useAlts = false;
   private int mcsLimit = -1;
+  private boolean enableOpentelemetry = false;
+  private String otelCollectorAddress;
+  private OpenTelemetrySdk openTelemetrySdk;
 
   private ScheduledExecutorService executor;
   private Server server;
@@ -123,6 +128,10 @@ void parseArgs(String[] args) {
         mcsLimit = Integer.parseInt(value);
         // TODO: Make Netty server builder usable for IPV6 as well (not limited to MCS handling)
         addressType = Util.AddressType.IPV4; // To use NettyServerBuilder
+      } else if ("enable_opentelemetry".equals(key)) {
+        enableOpentelemetry = Boolean.parseBoolean(value);
+      } else if ("otel_collector_address".equals(key)) {
+        otelCollectorAddress = value;
       } else {
         System.err.println("Unknown argument: " + key);
         usage = true;
@@ -155,7 +164,11 @@ void parseArgs(String[] args) {
 
   @SuppressWarnings("AddressSelection")
   @VisibleForTesting
+  @IgnoreJRERequirement // OpenTelemetry uses Java 8+ APIs
   void start() throws Exception {
+    if (enableOpentelemetry) {
+      this.openTelemetrySdk = OpenTelemetryUtil.setupOpenTelemetry(otelCollectorAddress);
+    }
     executor = Executors.newSingleThreadScheduledExecutor();
     ServerCredentials serverCreds;
     if (useAlts) {
@@ -224,11 +237,17 @@ void start() throws Exception {
 
   @VisibleForTesting
   void stop() throws Exception {
-    server.shutdownNow();
-    if (!server.awaitTermination(5, TimeUnit.SECONDS)) {
-      System.err.println("Timed out waiting for server shutdown");
+    try {
+      server.shutdownNow();
+      if (!server.awaitTermination(5, TimeUnit.SECONDS)) {
+        System.err.println("Timed out waiting for server shutdown");
+      }
+      MoreExecutors.shutdownAndAwaitTermination(executor, 5, TimeUnit.SECONDS);
+    } finally {
+      if (openTelemetrySdk != null) {
+        openTelemetrySdk.close();
+      }
     }
-    MoreExecutors.shutdownAndAwaitTermination(executor, 5, TimeUnit.SECONDS);
   }
 
   @VisibleForTesting