Add gRPC export for profiles signal type.

Changes per code review feedback

Author: jhalliday

exporters/otlp/profiles/build.gradle.kts

@@ -16,7 +16,7 @@ dependencies {
   implementation(project(":exporters:otlp:common"))
 
   implementation(project(":exporters:otlp:all"))
-  implementation("io.grpc:grpc-stub")
+  compileOnly("io.grpc:grpc-stub")
 
   annotationProcessor("com.google.auto.value:auto-value")
 
@@ -26,4 +26,5 @@ dependencies {
   testImplementation("io.opentelemetry.proto:opentelemetry-proto")
   testImplementation(project(":exporters:otlp:testing-internal"))
   testImplementation(project(":exporters:sender:okhttp"))
+  testImplementation("io.grpc:grpc-stub")
 }

exporters/otlp/profiles/src/main/java/io/opentelemetry/exporter/otlp/profiles/MultiProfilesExporter.java

@@ -8,16 +8,16 @@
 import io.opentelemetry.sdk.common.CompletableResultCode;
 import java.util.Collection;
 
-final class NoopProfilesExporter implements ProfilesExporter {
+final class NoopProfileExporter implements ProfileExporter {
 
-  private static final ProfilesExporter INSTANCE = new NoopProfilesExporter();
+  private static final ProfileExporter INSTANCE = new NoopProfileExporter();
 
-  static ProfilesExporter getInstance() {
+  static ProfileExporter getInstance() {
     return INSTANCE;
   }
 
   @Override
-  public CompletableResultCode export(Collection<ProfileData> spans) {
+  public CompletableResultCode export(Collection<ProfileData> profiles) {
     return CompletableResultCode.ofSuccess();
   }
 

exporters/otlp/profiles/src/main/java/io/opentelemetry/exporter/otlp/profiles/NoopProfilesExporter.java renamed to exporters/otlp/profiles/src/main/java/io/opentelemetry/exporter/otlp/profiles/NoopProfileExporter.java

@@ -15,20 +15,20 @@
 
 /** Exports profiles using OTLP via gRPC, using OpenTelemetry's protobuf model. */
 @ThreadSafe
-public class OtlpGrpcProfilesExporter implements ProfilesExporter {
+public class OtlpGrpcProfileExporter implements ProfileExporter {
 
   private final GrpcExporterBuilder<Marshaler> builder;
   private final GrpcExporter<Marshaler> delegate;
 
   /**
-   * Returns a new {@link OtlpGrpcProfilesExporter} using the default values.
+   * Returns a new {@link OtlpGrpcProfileExporter} using the default values.
    *
    * <p>To load configuration values from environment variables and system properties, use <a
    * href="https://github.com/open-telemetry/opentelemetry-java/tree/main/sdk-extensions/autoconfigure">opentelemetry-sdk-extension-autoconfigure</a>.
    *
-   * @return a new {@link OtlpGrpcProfilesExporter} instance.
+   * @return a new {@link OtlpGrpcProfileExporter} instance.
    */
-  public static OtlpGrpcProfilesExporter getDefault() {
+  public static OtlpGrpcProfileExporter getDefault() {
     return builder().build();
   }
 
@@ -41,7 +41,7 @@ public static OtlpGrpcProfilesExporterBuilder builder() {
     return new OtlpGrpcProfilesExporterBuilder();
   }
 
-  OtlpGrpcProfilesExporter(
+  OtlpGrpcProfileExporter(
       GrpcExporterBuilder<Marshaler> builder, GrpcExporter<Marshaler> delegate) {
     this.builder = builder;
     this.delegate = delegate;

exporters/otlp/profiles/src/main/java/io/opentelemetry/exporter/otlp/profiles/OtlpGrpcProfilesExporter.java renamed to exporters/otlp/profiles/src/main/java/io/opentelemetry/exporter/otlp/profiles/OtlpGrpcProfileExporter.java

@@ -40,6 +40,8 @@ public final class OtlpGrpcProfilesExporterBuilder {
   private static final URI DEFAULT_ENDPOINT = URI.create(DEFAULT_ENDPOINT_URL);
   private static final long DEFAULT_TIMEOUT_SECS = 10;
 
+  // TODO maybe make more efficient by adding support for MEMORY_MODE
+
   // Visible for testing
   final GrpcExporterBuilder<Marshaler> delegate;
 
@@ -227,7 +229,7 @@ public OtlpGrpcProfilesExporterBuilder setExecutorService(ExecutorService execut
    *
    * @return a new exporter's instance
    */
-  public OtlpGrpcProfilesExporter build() {
-    return new OtlpGrpcProfilesExporter(delegate, delegate.build());
+  public OtlpGrpcProfileExporter build() {
+    return new OtlpGrpcProfileExporter(delegate, delegate.build());
   }
 }

exporters/otlp/profiles/src/main/java/io/opentelemetry/exporter/otlp/profiles/OtlpGrpcProfilesExporterBuilder.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.exporter.otlp.profiles;
+
+import io.opentelemetry.sdk.common.CompletableResultCode;
+import java.io.Closeable;
+import java.util.Collection;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * An interface that allows different profiling services to export recorded data in their own
+ * format.
+ */
+public interface ProfileExporter extends Closeable {
+
+  /**
+   * Called to export sampled {@code ProfileData}s. Note that export operations can be performed
+   * simultaneously depending on the type of processor being used.
+   *
+   * @param profiles the collection of sampled profiles to be exported.
+   * @return the result of the export, which is often an asynchronous operation.
+   */
+  CompletableResultCode export(Collection<ProfileData> profiles);
+
+  /**
+   * Exports the collection of sampled {@code ProfileData}s that have not yet been exported. Note
+   * that export operations can be performed simultaneously depending on the type of span processor
+   * being used.
+   *
+   * @return the result of the flush, which is often an asynchronous operation.
+   */
+  CompletableResultCode flush();
+
+  /**
+   * Asynchronously terminate operation of the exporter.
+   *
+   * @return a {@link CompletableResultCode} which is completed when shutdown completes.
+   */
+  CompletableResultCode shutdown();
+
+  /** Closes this {@link ProfileExporter}, releasing any resources. */
+  @Override
+  default void close() {
+    shutdown().join(10, TimeUnit.SECONDS);
+  }
+}

exporters/otlp/profiles/src/main/java/io/opentelemetry/exporter/otlp/profiles/ProfileExporter.java

@@ -14,7 +14,7 @@
 import java.util.Collections;
 
 // TODO eventually merge with io.opentelemetry.exporter.otlp.testing.internal.FakeTelemetryUtil
-public class FakeTelemetryUtil {
+class FakeTelemetryUtil {
 
   private FakeTelemetryUtil() {}
 
@@ -25,7 +25,7 @@ private FakeTelemetryUtil() {}
           .build();
 
   /** Generate a fake {@link ProfileData}. */
-  public static ProfileData generateFakeProfileData() {
+  static ProfileData generateFakeProfileData() {
     String profileId = "0123456789abcdef0123456789abcdef";
     return ImmutableProfileData.create(
         Resource.create(Attributes.empty()),