Adds OLTP GRPC span exporter support

Signed-off-by: Gagan Juneja <gjjuneja@amazon.com>

plugins/telemetry-otel/build.gradle

@@ -29,6 +29,11 @@ dependencies {
   api "io.opentelemetry:opentelemetry-semconv:${versions.opentelemetry}-alpha"
   api "io.opentelemetry:opentelemetry-sdk-logs:${versions.opentelemetry}-alpha"
   api "io.opentelemetry:opentelemetry-api-logs:${versions.opentelemetry}-alpha"
+  api "io.opentelemetry:opentelemetry-exporter-otlp-common:${versions.opentelemetry}"
+  api "io.opentelemetry:opentelemetry-exporter-otlp:${versions.opentelemetry}"
+  api 'com.squareup.okhttp3:okhttp:4.10.0'
+  api 'org.jetbrains.kotlin:kotlin-stdlib:1.6.20'
+  api 'com.squareup.okio:okio-jvm:3.0.0'
 }
 
 

plugins/telemetry-otel/src/main/java/org/opensearch/telemetry/tracing/OTelResourceProvider.java

@@ -23,6 +23,7 @@
 import org.opensearch.common.settings.Settings;
 
 import java.util.concurrent.TimeUnit;
+import org.opensearch.telemetry.tracing.exporter.SpanExporterFactory;
 
 import static org.opensearch.telemetry.OTelTelemetryPlugin.TRACER_EXPORTER_BATCH_SIZE_SETTING;
 import static org.opensearch.telemetry.OTelTelemetryPlugin.TRACER_EXPORTER_DELAY_SETTING;
@@ -32,6 +33,8 @@
  * This class encapsulates all OpenTelemetry related resources
  */
 public final class OTelResourceProvider {
+
+    private static final SpanExporterFactory spanExporterFactory = new SpanExporterFactory();
     private OTelResourceProvider() {}
 
     /**
@@ -40,6 +43,7 @@ private OTelResourceProvider() {}
      * @return OpenTelemetry instance
      */
     public static OpenTelemetry get(Settings settings) {
+        SpanExporter spanExporter = spanExporterFactory.create(settings);
         return get(
             settings,
             new LoggingSpanExporter(),

plugins/telemetry-otel/src/main/java/org/opensearch/telemetry/tracing/exporter/SpanExporterFactory.java

@@ -0,0 +1,59 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.telemetry.tracing.exporter;
+
+import io.opentelemetry.exporter.logging.LoggingSpanExporter;
+import io.opentelemetry.exporter.otlp.trace.OtlpGrpcSpanExporter;
+import io.opentelemetry.sdk.trace.export.SpanExporter;
+import org.opensearch.common.settings.Setting;
+import org.opensearch.common.settings.Settings;
+
+import static org.opensearch.telemetry.OTelTelemetryPlugin.TRACER_EXPORTER_DELAY_SETTING;
+
+/**
+ * Factory class to create the {@link SpanExporter} instance.
+ */
+public class SpanExporterFactory {
+
+    /**
+     * Span Exporter type setting.
+     */
+    public static final Setting<SpanExporterType> TRACER_SPAN_EXPORTER_TYPE_SETTING = new Setting<>(
+        "telemetry.tracer.span.exporter.type",
+        SpanExporterType.LOGGING.name(),
+        SpanExporterType::fromString,
+        Setting.Property.NodeScope,
+        Setting.Property.Dynamic
+    );
+
+    /**
+     * Base constructor.
+     */
+    public SpanExporterFactory() {
+
+    }
+
+    /**
+     * Creates the {@link SpanExporter} instaces based on the TRACER_SPAN_EXPORTER_TYPE_SETTING value.
+     * @param settings settings.
+     * @return SpanExporter instance.
+     */
+    public SpanExporter create(Settings settings) {
+        SpanExporterType exporterType = TRACER_SPAN_EXPORTER_TYPE_SETTING.get(settings);
+        switch (exporterType) {
+            case OLTP_GRPC:
+                //TODO: For now just giving default implementation, but we need to use otel autoconfigue to expose
+                // all the configurations.
+                return OtlpGrpcSpanExporter.builder().build();
+            case LOGGING:
+            default:
+                return LoggingSpanExporter.create();
+        }
+    }
+}

plugins/telemetry-otel/src/main/java/org/opensearch/telemetry/tracing/exporter/SpanExporterType.java

@@ -0,0 +1,36 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.telemetry.tracing.exporter;
+
+import java.util.Arrays;
+
+/**
+ * Span Exporter type. For now, we are just supporting the 2 main types. But the idea is to make it configurable
+ * through otel autoconfigure.
+ */
+public enum SpanExporterType {
+
+    LOGGING, OLTP_GRPC;
+
+    /**
+     * Creates the {@link SpanExporterType} instance from the String.
+     * @param name
+     * @return
+     */
+    public static SpanExporterType fromString(String name) {
+        for (SpanExporterType exporterType : values()) {
+            if (exporterType.name().equalsIgnoreCase(name)) {
+                return exporterType;
+            }
+        }
+        throw new IllegalArgumentException(
+            "invalid value for tracing level [" + name + "], " + "must be in " + Arrays.asList(SpanExporterType.values())
+        );
+    }
+}

plugins/telemetry-otel/src/main/plugin-metadata/plugin-security.policy

@@ -7,6 +7,8 @@
  */
 
 grant {
+    permission java.net.NetPermission "getProxySelector";
+    permission java.net.SocketPermission "127.0.0.1:4317", "connect,resolve";
 };
 
 

plugins/telemetry-otel/src/test/java/org/opensearch/telemetry/tracing/exporter/SpanExporterFactoryTest.java

@@ -0,0 +1,44 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.telemetry.tracing.exporter;
+
+import io.opentelemetry.exporter.logging.LoggingSpanExporter;
+import io.opentelemetry.exporter.otlp.trace.OtlpGrpcSpanExporter;
+import io.opentelemetry.sdk.trace.export.SpanExporter;
+import org.opensearch.common.settings.Settings;
+import org.opensearch.test.OpenSearchTestCase;
+
+
+public class SpanExporterFactoryTest extends OpenSearchTestCase {
+
+    private final SpanExporterFactory spanExporterFactory = new SpanExporterFactory();
+
+    public void testSpanExporterDefault() {
+        Settings settings = Settings.builder().build();
+        SpanExporter spanExporter = spanExporterFactory.create(settings);
+        assertTrue(spanExporter instanceof LoggingSpanExporter);
+    }
+
+    public void testSpanExporterLogging() {
+        Settings settings = Settings.builder().put(SpanExporterFactory.TRACER_SPAN_EXPORTER_TYPE_SETTING.getKey(), "logging").build();
+        SpanExporter spanExporter = spanExporterFactory.create(settings);
+        assertTrue(spanExporter instanceof LoggingSpanExporter);
+    }
+
+    public void testSpanExporterGrpc() {
+        Settings settings = Settings.builder().put(SpanExporterFactory.TRACER_SPAN_EXPORTER_TYPE_SETTING.getKey(), "OLTP_GRPC").build();
+        SpanExporter spanExporter = spanExporterFactory.create(settings);
+        assertTrue(spanExporter instanceof OtlpGrpcSpanExporter);
+    }
+
+    public void testSpanExporterInvalid() {
+        Settings settings = Settings.builder().put(SpanExporterFactory.TRACER_SPAN_EXPORTER_TYPE_SETTING.getKey(), "abc").build();
+        assertThrows(IllegalArgumentException.class, () -> spanExporterFactory.create(settings));
+    }
+}