Update OTLP Trace Example to use Auth Extension (#391)

* Add required dependencies

* Use auth extension for OTLP example

* Make empty classifier name more apparent

Author: psx95

build.gradle

@@ -165,7 +165,7 @@ subprojects {
 		openTelemetryInstrumentationBomVersion = '2.8.0'
 		openTelemetryInstrumentationVersion = '2.8.0'
 		openTelemetrySemconvVersion = '1.27.0'
-		openTelemetryContribVersion = '1.39.0'
+		openTelemetryContribVersion = '1.43.0'
 		junitVersion = '4.13'
 		junit5Version = '5.10.0'
 		mockitoVersion = '5.2.0'
@@ -212,6 +212,7 @@ subprojects {
 			opentelemetry_otlp_exporter      : "io.opentelemetry:opentelemetry-exporter-otlp:${openTelemetryVersion}",
 			opentelemetry_logging_exporter   : "io.opentelemetry:opentelemetry-exporter-logging:${openTelemetryVersion}",
 			opentelemetry_gcp_resources      : "io.opentelemetry.contrib:opentelemetry-gcp-resources:${openTelemetryContribVersion}-alpha",
+			opentelemetry_gcp_auth_extension : "io.opentelemetry.contrib:opentelemetry-gcp-auth-extension:${openTelemetryContribVersion}-alpha",
 			spring_boot_starter              : "org.springframework.boot:spring-boot-starter:${springVersion}",
 			spring_boot_starter_web          : "org.springframework.boot:spring-boot-starter-web:${springWebVersion}",
 			spring_boot_starter_actuator     : "org.springframework.boot:spring-boot-starter-actuator:${springVersion}",

examples/otlptrace/README.md

@@ -17,15 +17,6 @@ Next, set your endpoint with the `OTEL_EXPORTER_OTLP_ENDPOINT` environment varia
 export OTEL_EXPORTER_OTLP_ENDPOINT="http://your-endpoint:port"
 ```
 
-Next, update [`build.gradle`](build.grade) to set the following:
-
-```
-	'-Dotel.resource.attributes=gcp.project_id=<YOUR_PROJECT_ID>,
-	'-Dotel.exporter.otlp.headers=X-Goog-User-Project=<YOUR_QUOTA_PROJECT>',
-	# Optional - if you want to export using gRPC protocol
-	'-Dotel.exporter.otlp.protocol=grpc',
-```
-
 Finally, to run the sample from the project root:
 
 ```

examples/otlptrace/build.gradle

@@ -20,28 +20,33 @@ plugins {
 // examples are not published, so version can be hardcoded
 version = '0.1.0'
 
-mainClassName = 'com.google.cloud.opentelemetry.example.otlptrace.OTLPTraceExample'
-
 description = 'Example for OTLP exporter'
 
+// the shaded variant name for gcp auth extension is an empty string
+def gcp_auth_extension_shaded_classifier = ''
+
 dependencies {
 	implementation(libraries.opentelemetry_api)
 	implementation(libraries.opentelemetry_sdk)
 	implementation(libraries.opentelemetry_otlp_exporter)
 	implementation(libraries.opentelemetry_sdk_autoconf)
-	implementation(libraries.google_auth)
+	implementation("${libraries.opentelemetry_gcp_auth_extension}:${gcp_auth_extension_shaded_classifier}")
+	implementation(libraries.opentelemetry_gcp_resources)
 }
 
 // Provide headers from env variable
-// export OTEL_EXPORTER_OTLP_ENDPOINT="http://path/to/yourendpoint:port"
 def autoconf_config = [
-	'-Dotel.resource.attributes=gcp.project_id=<YOUR_PROJECT>',
-	'-Dotel.exporter.otlp.headers=X-Goog-User-Project=<YOUR_QUOTA_PROJECT>',
+	'-Dgoogle.cloud.project=your-gcp-project-id',
+	'-Dotel.exporter.otlp.endpoint=https://your-api-endpoint:port',
 	'-Dotel.traces.exporter=otlp',
+	'-Dotel.logs.exporter=none',
+	'-Dotel.metrics.exporter=none',
+	'-Dotel.service.name=otlptrace-example',
 	'-Dotel.exporter.otlp.protocol=http/protobuf',
 	'-Dotel.java.global-autoconfigure.enabled=true',
 ]
 
 application {
+	mainClassName = 'com.google.cloud.opentelemetry.example.otlptrace.OTLPTraceExample'
 	applicationDefaultJvmArgs = autoconf_config
 }

examples/otlptrace/src/main/java/com/google/cloud/opentelemetry/example/otlptrace/OTLPTraceExample.java

@@ -15,17 +15,11 @@
  */
 package com.google.cloud.opentelemetry.example.otlptrace;
 
-import com.google.auth.oauth2.GoogleCredentials;
 import io.opentelemetry.api.trace.Span;
 import io.opentelemetry.context.Scope;
-import io.opentelemetry.exporter.otlp.http.trace.OtlpHttpSpanExporter;
-import io.opentelemetry.exporter.otlp.http.trace.OtlpHttpSpanExporterBuilder;
-import io.opentelemetry.exporter.otlp.trace.OtlpGrpcSpanExporter;
-import io.opentelemetry.exporter.otlp.trace.OtlpGrpcSpanExporterBuilder;
 import io.opentelemetry.sdk.OpenTelemetrySdk;
 import io.opentelemetry.sdk.autoconfigure.AutoConfiguredOpenTelemetrySdk;
 import io.opentelemetry.sdk.common.CompletableResultCode;
-import io.opentelemetry.sdk.trace.export.SpanExporter;
 import java.io.IOException;
 import java.util.Random;
 import java.util.concurrent.TimeUnit;
@@ -36,52 +30,6 @@ public class OTLPTraceExample {
 
   private static OpenTelemetrySdk openTelemetrySdk;
 
-  private static OpenTelemetrySdk setupTraceExporter() throws IOException {
-    GoogleCredentials credentials = GoogleCredentials.getApplicationDefault();
-
-    // Update the SDK configured using environment variables and system properties
-    AutoConfiguredOpenTelemetrySdk autoConfOTelSdk =
-        AutoConfiguredOpenTelemetrySdk.builder()
-            .addSpanExporterCustomizer(
-                (exporter, configProperties) -> addAuthorizationHeaders(exporter, credentials))
-            .build();
-    return autoConfOTelSdk.getOpenTelemetrySdk();
-  }
-
-  // Modifies the span exporter initially auto-configured using environment variables
-  // Note: This adds static authorization headers which are set only at initialization time.
-  // This will stop working after the token expires, since the token is not refreshed.
-  private static SpanExporter addAuthorizationHeaders(
-      SpanExporter exporter, GoogleCredentials credentials) {
-    if (exporter instanceof OtlpHttpSpanExporter) {
-      try {
-        credentials.refreshIfExpired();
-        OtlpHttpSpanExporterBuilder builder =
-            ((OtlpHttpSpanExporter) exporter)
-                .toBuilder()
-                    .addHeader(
-                        "Authorization", "Bearer " + credentials.getAccessToken().getTokenValue());
-
-        return builder.build();
-      } catch (IOException e) {
-        System.out.println("error:" + e.getMessage());
-      }
-    } else if (exporter instanceof OtlpGrpcSpanExporter) {
-      try {
-        credentials.refreshIfExpired();
-        OtlpGrpcSpanExporterBuilder builder =
-            ((OtlpGrpcSpanExporter) exporter)
-                .toBuilder()
-                    .addHeader(
-                        "Authorization", "Bearer " + credentials.getAccessToken().getTokenValue());
-        return builder.build();
-      } catch (IOException e) {
-        throw new RuntimeException(e);
-      }
-    }
-    return exporter;
-  }
-
   private static void myUseCase(String description) {
     // Generate a span
     Span span =
@@ -93,7 +41,6 @@ private static void myUseCase(String description) {
         String work = String.format("%s - Work #%d", description, (i + 1));
         doWork(work);
       }
-
       span.addEvent("Event B");
     } finally {
       span.end();
@@ -106,7 +53,9 @@ private static void doWork(String description) {
         openTelemetrySdk.getTracer(INSTRUMENTATION_SCOPE_NAME).spanBuilder(description).startSpan();
     try (Scope scope = span.makeCurrent()) {
       // Simulate work: this could be simulating a network request or an expensive disk operation
-      Thread.sleep(100 + random.nextInt(5) * 100);
+      int randomSleep = random.nextInt(5) * 100;
+      span.setAttribute("RandomSleep", randomSleep);
+      Thread.sleep(100 + randomSleep);
     } catch (InterruptedException e) {
       throw new RuntimeException(e);
     } finally {
@@ -116,7 +65,7 @@ private static void doWork(String description) {
 
   public static void main(String[] args) throws IOException {
     // Configure the OpenTelemetry pipeline with CloudTrace exporter
-    openTelemetrySdk = setupTraceExporter();
+    openTelemetrySdk = AutoConfiguredOpenTelemetrySdk.initialize().getOpenTelemetrySdk();
 
     // Application-specific logic
     myUseCase("One");