Add gRPC authenticator for exporter

exporters/common/src/main/java/io/opentelemetry/exporter/internal/auth/Authenticator.java

@@ -41,7 +41,7 @@ static void setAuthenticatorOnDelegate(Object builder, Authenticator authenticat
       field.setAccessible(true);
       Object value = field.get(builder);
       if (value instanceof GrpcExporterBuilder) {
-        throw new IllegalArgumentException("GrpcExporterBuilder not supported yet.");
+        ((GrpcExporterBuilder<?>) value).setAuthenticator(authenticator);
       } else if (value instanceof HttpExporterBuilder) {
         ((HttpExporterBuilder<?>) value).setAuthenticator(authenticator);
       } else {

exporters/common/src/main/java/io/opentelemetry/exporter/internal/grpc/GrpcExporterBuilder.java

@@ -12,6 +12,7 @@
 import io.opentelemetry.api.metrics.MeterProvider;
 import io.opentelemetry.exporter.internal.ExporterBuilderUtil;
 import io.opentelemetry.exporter.internal.TlsConfigHelper;
+import io.opentelemetry.exporter.internal.auth.Authenticator;
 import io.opentelemetry.exporter.internal.compression.Compressor;
 import io.opentelemetry.exporter.internal.marshal.Marshaler;
 import io.opentelemetry.sdk.common.export.RetryPolicy;
@@ -62,6 +63,7 @@ public class GrpcExporterBuilder<T extends Marshaler> {
   private TlsConfigHelper tlsConfigHelper = new TlsConfigHelper();
   @Nullable private RetryPolicy retryPolicy = RetryPolicy.getDefault();
   private Supplier<MeterProvider> meterProviderSupplier = GlobalOpenTelemetry::getMeterProvider;
+  @Nullable private Authenticator authenticator;
 
   // Use Object type since gRPC may not be on the classpath.
   @Nullable private Object grpcChannel;
@@ -147,6 +149,11 @@ public GrpcExporterBuilder<T> setMeterProvider(Supplier<MeterProvider> meterProv
     return this;
   }
 
+  public GrpcExporterBuilder<T> setAuthenticator(Authenticator authenticator) {
+    this.authenticator = authenticator;
+    return this;
+  }
+
   @SuppressWarnings("BuilderReturnThis")
   public GrpcExporterBuilder<T> copy() {
     GrpcExporterBuilder<T> copy =
@@ -209,7 +216,8 @@ public GrpcExporter<T> build() {
             grpcStubFactory,
             retryPolicy,
             isPlainHttp ? null : tlsConfigHelper.getSslContext(),
-            isPlainHttp ? null : tlsConfigHelper.getTrustManager());
+            isPlainHttp ? null : tlsConfigHelper.getTrustManager(),
+            authenticator);
     LOGGER.log(Level.FINE, "Using GrpcSender: " + grpcSender.getClass().getName());
 
     return new GrpcExporter<>(exporterName, type, grpcSender, meterProviderSupplier);

exporters/common/src/main/java/io/opentelemetry/exporter/internal/grpc/GrpcSenderProvider.java

@@ -6,6 +6,7 @@
 package io.opentelemetry.exporter.internal.grpc;
 
 import io.grpc.Channel;
+import io.opentelemetry.exporter.internal.auth.Authenticator;
 import io.opentelemetry.exporter.internal.compression.Compressor;
 import io.opentelemetry.exporter.internal.marshal.Marshaler;
 import io.opentelemetry.sdk.common.export.RetryPolicy;
@@ -40,5 +41,6 @@ <T extends Marshaler> GrpcSender<T> createSender(
       Supplier<BiFunction<Channel, String, MarshalerServiceStub<T, ?, ?>>> stubFactory,
       @Nullable RetryPolicy retryPolicy,
       @Nullable SSLContext sslContext,
-      @Nullable X509TrustManager trustManager);
+      @Nullable X509TrustManager trustManager,
+      @Nullable Authenticator authenticator);
 }

exporters/common/src/main/resources/META-INF/native-image/io.opentelemetry.opentelemetry-exporter-common/reflect-config.json

@@ -10,5 +10,9 @@
   {
     "name":"io.opentelemetry.exporter.internal.compression.Compressor",
     "queryAllDeclaredMethods":true
+  },
+  {
+    "name":"io.opentelemetry.exporter.internal.auth.Authenticator",
+    "queryAllDeclaredMethods":true
   }
 ]

exporters/common/src/test/java/io/opentelemetry/exporter/internal/auth/AuthenticatorTest.java

@@ -10,7 +10,9 @@
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 
 import io.opentelemetry.exporter.internal.grpc.GrpcExporter;
+import io.opentelemetry.exporter.internal.grpc.GrpcExporterBuilder;
 import io.opentelemetry.exporter.internal.http.HttpExporterBuilder;
+import java.net.URI;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
@@ -31,16 +33,22 @@ void getHeaders() {
 
   @Test
   void setAuthenticatorOnDelegate_Success() {
-    HttpExporterBuilder<?> builder =
+    // For HTTP exporter
+    HttpExporterBuilder<?> httpBuilder =
         new HttpExporterBuilder<>("otlp", "test", "http://localhost:4318/test");
-
-    assertThat(builder).extracting("authenticator").isNull();
-
+    assertThat(httpBuilder).extracting("authenticator").isNull();
     Authenticator authenticator = Collections::emptyMap;
+    Authenticator.setAuthenticatorOnDelegate(new WithDelegate(httpBuilder), authenticator);
+    assertThat(httpBuilder)
+        .extracting("authenticator", as(InstanceOfAssertFactories.type(Authenticator.class)))
+        .isSameAs(authenticator);
 
-    Authenticator.setAuthenticatorOnDelegate(new WithDelegate(builder), authenticator);
-
-    assertThat(builder)
+    // For GRPC exporter
+    GrpcExporterBuilder<?> grpcBuilder =
+        new GrpcExporterBuilder<>("otlp", "test", 60, URI.create("test"), null, "/test");
+    assertThat(grpcBuilder).extracting("authenticator").isNull();
+    Authenticator.setAuthenticatorOnDelegate(new WithDelegate(grpcBuilder), authenticator);
+    assertThat(grpcBuilder)
         .extracting("authenticator", as(InstanceOfAssertFactories.type(Authenticator.class)))
         .isSameAs(authenticator);
   }

exporters/otlp/all/src/jmh/java/io/opentelemetry/exporter/otlp/trace/OltpExporterBenchmark.java

@@ -105,6 +105,7 @@ public void setUp() {
                 Collections::emptyMap,
                 null,
                 null,
+                null,
                 null),
             MeterProvider::noop);
 

exporters/sender/grpc-managed-channel/src/main/java/io/opentelemetry/exporter/sender/grpc/managedchannel/internal/UpstreamGrpcSenderProvider.java

@@ -5,11 +5,16 @@
 
 package io.opentelemetry.exporter.sender.grpc.managedchannel.internal;
 
+import static io.grpc.Metadata.ASCII_STRING_MARSHALLER;
+
+import io.grpc.CallCredentials;
 import io.grpc.Channel;
 import io.grpc.Codec;
 import io.grpc.CompressorRegistry;
 import io.grpc.ManagedChannel;
 import io.grpc.ManagedChannelBuilder;
+import io.grpc.Metadata;
+import io.opentelemetry.exporter.internal.auth.Authenticator;
 import io.opentelemetry.exporter.internal.compression.Compressor;
 import io.opentelemetry.exporter.internal.grpc.GrpcSender;
 import io.opentelemetry.exporter.internal.grpc.GrpcSenderProvider;
@@ -21,6 +26,7 @@
 import java.net.URI;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.Executor;
 import java.util.function.BiFunction;
 import java.util.function.Supplier;
 import javax.annotation.Nullable;
@@ -47,7 +53,8 @@ public <T extends Marshaler> GrpcSender<T> createSender(
       Supplier<BiFunction<Channel, String, MarshalerServiceStub<T, ?, ?>>> stubFactory,
       @Nullable RetryPolicy retryPolicy,
       @Nullable SSLContext sslContext,
-      @Nullable X509TrustManager trustManager) {
+      @Nullable X509TrustManager trustManager,
+      @Nullable Authenticator authenticator) {
     boolean shutdownChannel = false;
     if (managedChannel == null) {
       // Shutdown the channel as part of the exporter shutdown sequence if
@@ -83,11 +90,29 @@ public OutputStream compress(OutputStream os) throws IOException {
       compression = compressor.getEncoding();
     }
 
+    CallCredentials cred =
+        new CallCredentials() {
+          @Override
+          public void applyRequestMetadata(
+              RequestInfo requestInfo, Executor executor, MetadataApplier metadataApplier) {
+            Metadata headers = new Metadata();
+            if (authenticator != null) {
+              // For each header provided in the authenticator, put it in the header of the
+              // Metadata.
+              for (Map.Entry<String, String> e : authenticator.getHeaders().entrySet()) {
+                headers.put(Metadata.Key.of(e.getKey(), ASCII_STRING_MARSHALLER), e.getValue());
+              }
+            }
+            metadataApplier.apply(headers);
+          }
+        };
+
     MarshalerServiceStub<T, ?, ?> stub =
         stubFactory
             .get()
             .apply((Channel) managedChannel, authorityOverride)
-            .withCompression(compression);
+            .withCompression(compression)
+            .withCallCredentials(cred);
 
     return new UpstreamGrpcSender<>(stub, shutdownChannel, timeoutNanos, headersSupplier);
   }

exporters/sender/okhttp/src/main/java/io/opentelemetry/exporter/sender/okhttp/internal/OkHttpGrpcSender.java

@@ -25,6 +25,7 @@
 
 import io.opentelemetry.api.internal.InstrumentationUtil;
 import io.opentelemetry.exporter.internal.RetryUtil;
+import io.opentelemetry.exporter.internal.auth.Authenticator;
 import io.opentelemetry.exporter.internal.compression.Compressor;
 import io.opentelemetry.exporter.internal.grpc.GrpcExporterUtil;
 import io.opentelemetry.exporter.internal.grpc.GrpcResponse;
@@ -42,6 +43,7 @@
 import java.util.Map;
 import java.util.function.Consumer;
 import java.util.function.Supplier;
+import java.util.stream.Collectors;
 import javax.annotation.Nullable;
 import javax.net.ssl.SSLContext;
 import javax.net.ssl.X509TrustManager;
@@ -80,7 +82,8 @@ public OkHttpGrpcSender(
       Supplier<Map<String, List<String>>> headersSupplier,
       @Nullable RetryPolicy retryPolicy,
       @Nullable SSLContext sslContext,
-      @Nullable X509TrustManager trustManager) {
+      @Nullable X509TrustManager trustManager,
+      @Nullable Authenticator authenticator) {
     OkHttpClient.Builder clientBuilder =
         new OkHttpClient.Builder()
             .dispatcher(OkHttpUtil.newDispatcher())
@@ -90,7 +93,6 @@ public OkHttpGrpcSender(
       clientBuilder.addInterceptor(
           new RetryInterceptor(retryPolicy, OkHttpGrpcSender::isRetryable));
     }
-
     boolean isPlainHttp = endpoint.startsWith("http://");
     if (isPlainHttp) {
       clientBuilder.connectionSpecs(Collections.singletonList(ConnectionSpec.CLEARTEXT));
@@ -102,6 +104,20 @@ public OkHttpGrpcSender(
       }
     }
 
+    if (authenticator != null) {
+      Map<String, List<String>> headers = headersSupplier.get();
+      // Convert the auth header type of Map<String, String> to the expected type of
+      // OkHttpGrpcSender of Map<String, List<String>>
+      Map<String, List<String>> authHeaders =
+          authenticator.getHeaders().entrySet().stream()
+              .collect(
+                  Collectors.toMap(
+                      Map.Entry::getKey, e -> Collections.singletonList(e.getValue())));
+      // The authenticator headers will override the default headers if there are duplicate keys.
+      headers.putAll(authHeaders);
+      headersSupplier = () -> headers;
+    }
+
     this.client = clientBuilder.build();
     this.headersSupplier = headersSupplier;
     this.url = HttpUrl.get(endpoint);

exporters/sender/okhttp/src/main/java/io/opentelemetry/exporter/sender/okhttp/internal/OkHttpGrpcSenderProvider.java

@@ -6,6 +6,7 @@
 package io.opentelemetry.exporter.sender.okhttp.internal;
 
 import io.grpc.Channel;
+import io.opentelemetry.exporter.internal.auth.Authenticator;
 import io.opentelemetry.exporter.internal.compression.Compressor;
 import io.opentelemetry.exporter.internal.grpc.GrpcSender;
 import io.opentelemetry.exporter.internal.grpc.GrpcSenderProvider;
@@ -41,7 +42,8 @@ public <T extends Marshaler> GrpcSender<T> createSender(
       Supplier<BiFunction<Channel, String, MarshalerServiceStub<T, ?, ?>>> stubFactory,
       @Nullable RetryPolicy retryPolicy,
       @Nullable SSLContext sslContext,
-      @Nullable X509TrustManager trustManager) {
+      @Nullable X509TrustManager trustManager,
+      @Nullable Authenticator authenticator) {
     return new OkHttpGrpcSender<>(
         endpoint.resolve(endpointPath).toString(),
         compressor,
@@ -50,6 +52,7 @@ public <T extends Marshaler> GrpcSender<T> createSender(
         headersSupplier,
         retryPolicy,
         sslContext,
-        trustManager);
+        trustManager,
+        authenticator);
   }
 }

exporters/sender/okhttp/src/test/java/io/opentelemetry/exporter/sender/okhttp/internal/OkHttpGrpcSuppressionTest.java

@@ -21,7 +21,7 @@ void send(OkHttpGrpcSender<DummyMarshaler> sender, Runnable onSuccess, Runnable
   @Override
   OkHttpGrpcSender<DummyMarshaler> createSender(String endpoint) {
     return new OkHttpGrpcSender<>(
-        "https://localhost", null, 10L, 10L, Collections::emptyMap, null, null, null);
+        "https://localhost", null, 10L, 10L, Collections::emptyMap, null, null, null, null);
   }
 
   protected static class DummyMarshaler extends MarshalerWithSize {