Expose AutoConfiguredOpenTelemetrySdk to AgentListener (#4831)

* Expose AutoConfiguredOpenTelemetrySdk to AgentListener

* Only call AgentListener if noop is disabled, deprecate AgentListener methods

* Call AgentListener in DelayedAfterAgentCallback

javaagent-extension-api/build.gradle.kts

@@ -16,4 +16,6 @@ dependencies {
 
   // metrics are unstable, do not expose as api
   implementation("io.opentelemetry:opentelemetry-sdk-metrics")
+  // autoconfigure is unstable, do not expose as api
+  implementation("io.opentelemetry:opentelemetry-sdk-extension-autoconfigure")
 }

javaagent-extension-api/src/main/java/io/opentelemetry/javaagent/extension/AgentListener.java

@@ -8,13 +8,14 @@ package io.opentelemetry.javaagent.extension;
 import io.opentelemetry.instrumentation.api.cache.Cache;
 import io.opentelemetry.instrumentation.api.config.Config;
 import io.opentelemetry.instrumentation.api.field.VirtualField;
+import io.opentelemetry.sdk.autoconfigure.AutoConfiguredOpenTelemetrySdk;
 import java.lang.instrument.Instrumentation;
 import net.bytebuddy.agent.builder.AgentBuilder;
 
 /**
  * {@link AgentListener} can be used to execute code before/after Java agent installation, for
- * example to install any implementation providers that are used by instrumentations. For instance,
- * this project uses this SPI to install OpenTelemetry SDK.
+ * example to install any implementation providers that are used by instrumentations. Can also be
+ * used to obtain the {@link AutoConfiguredOpenTelemetrySdk}.
  *
  * <p>This is a service provider interface that requires implementations to be registered in a
  * provider-configuration file stored in the {@code META-INF/services} resource directory.
@@ -22,18 +23,44 @@ import net.bytebuddy.agent.builder.AgentBuilder;
 public interface AgentListener extends Ordered {
 
   /**
-   * Runs before the {@link AgentBuilder} construction, before any instrumentation is added.
+   * Runs before {@link AgentBuilder} construction, before any instrumentation is added.
    *
-   * <p>Execute only a minimal code because any classes loaded before the agent installation will
-   * have to be retransformed, which takes extra time, and more importantly means that fields can't
-   * be added to those classes - which causes {@link VirtualField} to fall back to the less
-   * performant {@link Cache} implementation for those classes.
+   * <p>Execute only minimal code because any classes loaded before the agent installation will have
+   * to be retransformed, which takes extra time, and more importantly means that fields can't be
+   * added to those classes - which causes {@link VirtualField} to fall back to the less performant
+   * {@link Cache} implementation for those classes.
+   *
+   * @deprecated Use {@link #beforeAgent(Config, AutoConfiguredOpenTelemetrySdk)}
    */
+  @Deprecated
   default void beforeAgent(Config config) {}
 
+  /**
+   * Runs before {@link AgentBuilder} construction, before any instrumentation is added. Not called
+   * if noop api enabled via {@code otel.javaagent.experimental.use-noop-api}.
+   *
+   * <p>Execute only minimal code because any classes loaded before the agent installation will have
+   * to be retransformed, which takes extra time, and more importantly means that fields can't be
+   * added to those classes - which causes {@link VirtualField} to fall back to the less performant
+   * {@link Cache} implementation for those classes.
+   */
+  default void beforeAgent(
+      Config config, AutoConfiguredOpenTelemetrySdk autoConfiguredOpenTelemetrySdk) {}
+
   /**
    * Runs after instrumentations are added to {@link AgentBuilder} and after the agent is installed
    * on an {@link Instrumentation}.
+   *
+   * @deprecated Use {@link #afterAgent(Config, AutoConfiguredOpenTelemetrySdk)}
    */
+  @Deprecated
   default void afterAgent(Config config) {}
+
+  /**
+   * Runs after instrumentations are added to {@link AgentBuilder} and after the agent is installed
+   * on an {@link Instrumentation}. Not called if noop api enabled via {@code
+   * otel.javaagent.experimental.use-noop-api}.
+   */
+  default void afterAgent(
+      Config config, AutoConfiguredOpenTelemetrySdk autoConfiguredOpenTelemetrySdk) {}
 }

javaagent-tooling/src/main/java/io/opentelemetry/javaagent/tooling/AgentInstaller.java

@@ -6,14 +6,17 @@
 package io.opentelemetry.javaagent.tooling;
 
 import static io.opentelemetry.javaagent.bootstrap.AgentInitializer.isJavaBefore9;
+import static io.opentelemetry.javaagent.tooling.OpenTelemetryInstaller.installOpenTelemetrySdk;
 import static io.opentelemetry.javaagent.tooling.SafeServiceLoader.load;
 import static io.opentelemetry.javaagent.tooling.SafeServiceLoader.loadOrdered;
 import static io.opentelemetry.javaagent.tooling.Utils.getResourceName;
 import static net.bytebuddy.matcher.ElementMatchers.any;
 
+import io.opentelemetry.api.GlobalOpenTelemetry;
 import io.opentelemetry.context.Context;
 import io.opentelemetry.context.ContextStorage;
 import io.opentelemetry.context.Scope;
+import io.opentelemetry.extension.noopapi.NoopOpenTelemetry;
 import io.opentelemetry.instrumentation.api.config.Config;
 import io.opentelemetry.javaagent.bootstrap.AgentClassLoader;
 import io.opentelemetry.javaagent.bootstrap.BootstrapPackagePrefixesHolder;
@@ -31,6 +34,7 @@ import io.opentelemetry.javaagent.tooling.ignore.IgnoredTypesBuilderImpl;
 import io.opentelemetry.javaagent.tooling.ignore.IgnoredTypesMatcher;
 import io.opentelemetry.javaagent.tooling.muzzle.AgentTooling;
 import io.opentelemetry.javaagent.tooling.util.Trie;
+import io.opentelemetry.sdk.autoconfigure.AutoConfiguredOpenTelemetrySdk;
 import java.lang.instrument.Instrumentation;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -53,7 +57,8 @@ public class AgentInstaller {
 
   private static final Logger logger;
 
-  private static final String JAVAAGENT_ENABLED_CONFIG = "otel.javaagent.enabled";
+  static final String JAVAAGENT_ENABLED_CONFIG = "otel.javaagent.enabled";
+  static final String JAVAAGENT_NOOP_CONFIG = "otel.javaagent.experimental.use-noop-api";
 
   // This property may be set to force synchronous AgentListener#afterAgent() execution: the
   // condition for delaying the AgentListener initialization is pretty broad and in case it covers
@@ -110,7 +115,19 @@ public class AgentInstaller {
 
     setBootstrapPackages(config);
 
-    runBeforeAgentListeners(agentListeners, config);
+    // If noop OpenTelemetry is enabled, autoConfiguredSdk will be null and AgentListeners are not
+    // called
+    AutoConfiguredOpenTelemetrySdk autoConfiguredSdk = null;
+    if (config.getBoolean(JAVAAGENT_NOOP_CONFIG, false)) {
+      logger.info("Tracing and metrics are disabled because noop is enabled.");
+      GlobalOpenTelemetry.set(NoopOpenTelemetry.getInstance());
+    } else {
+      autoConfiguredSdk = installOpenTelemetrySdk(config);
+    }
+
+    if (autoConfiguredSdk != null) {
+      runBeforeAgentListeners(agentListeners, config, autoConfiguredSdk);
+    }
 
     AgentBuilder agentBuilder =
         new AgentBuilder.Default()
@@ -157,7 +174,11 @@ public class AgentInstaller {
 
     ResettableClassFileTransformer resettableClassFileTransformer = agentBuilder.installOn(inst);
     ClassFileTransformerHolder.setClassFileTransformer(resettableClassFileTransformer);
-    runAfterAgentListeners(agentListeners, config);
+
+    if (autoConfiguredSdk != null) {
+      runAfterAgentListeners(agentListeners, config, autoConfiguredSdk);
+    }
+
     return resettableClassFileTransformer;
   }
 
@@ -178,9 +199,12 @@ public class AgentInstaller {
   }
 
   private static void runBeforeAgentListeners(
-      Iterable<AgentListener> agentListeners, Config config) {
+      Iterable<AgentListener> agentListeners,
+      Config config,
+      AutoConfiguredOpenTelemetrySdk autoConfiguredSdk) {
     for (AgentListener agentListener : agentListeners) {
       agentListener.beforeAgent(config);
+      agentListener.beforeAgent(config, autoConfiguredSdk);
     }
   }
 
@@ -199,7 +223,9 @@ public class AgentInstaller {
   }
 
   private static void runAfterAgentListeners(
-      Iterable<AgentListener> agentListeners, Config config) {
+      Iterable<AgentListener> agentListeners,
+      Config config,
+      AutoConfiguredOpenTelemetrySdk autoConfiguredSdk) {
     // java.util.logging.LogManager maintains a final static LogManager, which is created during
     // class initialization. Some AgentListener implementations may use JRE bootstrap classes
     // which touch this class (e.g. JFR classes or some MBeans).
@@ -223,10 +249,12 @@ public class AgentInstaller {
         && isAppUsingCustomLogManager()) {
       logger.debug("Custom JUL LogManager detected: delaying AgentListener#afterAgent() calls");
       registerClassLoadCallback(
-          "java.util.logging.LogManager", new DelayedAfterAgentCallback(config, agentListeners));
+          "java.util.logging.LogManager",
+          new DelayedAfterAgentCallback(config, agentListeners, autoConfiguredSdk));
     } else {
       for (AgentListener agentListener : agentListeners) {
         agentListener.afterAgent(config);
+        agentListener.afterAgent(config, autoConfiguredSdk);
       }
     }
   }
@@ -326,10 +354,15 @@ public class AgentInstaller {
   private static class DelayedAfterAgentCallback implements Runnable {
     private final Iterable<AgentListener> agentListeners;
     private final Config config;
+    private final AutoConfiguredOpenTelemetrySdk autoConfiguredSdk;
 
-    private DelayedAfterAgentCallback(Config config, Iterable<AgentListener> agentListeners) {
+    private DelayedAfterAgentCallback(
+        Config config,
+        Iterable<AgentListener> agentListeners,
+        AutoConfiguredOpenTelemetrySdk autoConfiguredSdk) {
       this.agentListeners = agentListeners;
       this.config = config;
+      this.autoConfiguredSdk = autoConfiguredSdk;
     }
 
     @Override
@@ -349,6 +382,7 @@ public class AgentInstaller {
       for (AgentListener agentListener : agentListeners) {
         try {
           agentListener.afterAgent(config);
+          agentListener.afterAgent(config, autoConfiguredSdk);
         } catch (RuntimeException e) {
           logger.error("Failed to execute {}", agentListener.getClass().getName(), e);
         }

javaagent-tooling/src/main/java/io/opentelemetry/javaagent/tooling/AgentTracerProviderConfigurer.java

@@ -5,6 +5,8 @@
 
 package io.opentelemetry.javaagent.tooling;
 
+import static io.opentelemetry.javaagent.tooling.AgentInstaller.JAVAAGENT_ENABLED_CONFIG;
+
 import com.google.auto.service.AutoService;
 import io.opentelemetry.exporter.logging.LoggingSpanExporter;
 import io.opentelemetry.instrumentation.api.config.Config;
@@ -24,7 +26,7 @@ public class AgentTracerProviderConfigurer implements SdkTracerProviderConfigure
   @Override
   public void configure(
       SdkTracerProviderBuilder sdkTracerProviderBuilder, ConfigProperties config) {
-    if (!Config.get().getBoolean(OpenTelemetryInstaller.JAVAAGENT_ENABLED_CONFIG, true)) {
+    if (!Config.get().getBoolean(JAVAAGENT_ENABLED_CONFIG, true)) {
       return;
     }
 

javaagent-tooling/src/main/java/io/opentelemetry/javaagent/tooling/OpenTelemetryInstaller.java

@@ -5,14 +5,10 @@
 
 package io.opentelemetry.javaagent.tooling;
 
-import com.google.auto.service.AutoService;
-import io.opentelemetry.api.GlobalOpenTelemetry;
 import io.opentelemetry.api.metrics.GlobalMeterProvider;
 import io.opentelemetry.api.metrics.MeterProvider;
-import io.opentelemetry.extension.noopapi.NoopOpenTelemetry;
 import io.opentelemetry.instrumentation.api.config.Config;
 import io.opentelemetry.javaagent.bootstrap.AgentInitializer;
-import io.opentelemetry.javaagent.extension.AgentListener;
 import io.opentelemetry.javaagent.instrumentation.api.OpenTelemetrySdkAccess;
 import io.opentelemetry.sdk.OpenTelemetrySdk;
 import io.opentelemetry.sdk.autoconfigure.AutoConfiguredOpenTelemetrySdk;
@@ -20,64 +16,46 @@ import io.opentelemetry.sdk.autoconfigure.AutoConfiguredOpenTelemetrySdkBuilder;
 import io.opentelemetry.sdk.common.CompletableResultCode;
 import io.opentelemetry.sdk.metrics.SdkMeterProvider;
 import java.util.Arrays;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
-@AutoService(AgentListener.class)
-public class OpenTelemetryInstaller implements AgentListener {
-  private static final Logger logger = LoggerFactory.getLogger(OpenTelemetryInstaller.class);
-
-  static final String JAVAAGENT_ENABLED_CONFIG = "otel.javaagent.enabled";
-  static final String JAVAAGENT_NOOP_CONFIG = "otel.javaagent.experimental.use-noop-api";
-
-  @Override
-  public void beforeAgent(Config config) {
-    installAgentTracer(config);
-  }
+public class OpenTelemetryInstaller {
 
   /**
-   * Register agent tracer if no agent tracer is already registered.
+   * Install the {@link OpenTelemetrySdk} using autoconfigure, and return the {@link
+   * AutoConfiguredOpenTelemetrySdk}.
    *
-   * @param config Configuration instance
+   * @return the {@link AutoConfiguredOpenTelemetrySdk}
    */
-  @SuppressWarnings("unused")
-  public static synchronized void installAgentTracer(Config config) {
-    if (config.getBoolean(JAVAAGENT_ENABLED_CONFIG, true)) {
+  static AutoConfiguredOpenTelemetrySdk installOpenTelemetrySdk(Config config) {
+    System.setProperty("io.opentelemetry.context.contextStorageProvider", "default");
 
-      if (config.getBoolean(JAVAAGENT_NOOP_CONFIG, false)) {
-        GlobalOpenTelemetry.set(NoopOpenTelemetry.getInstance());
-      } else {
-        System.setProperty("io.opentelemetry.context.contextStorageProvider", "default");
+    AutoConfiguredOpenTelemetrySdkBuilder builder =
+        AutoConfiguredOpenTelemetrySdk.builder()
+            .setResultAsGlobal(true)
+            .addPropertiesSupplier(config::getAllProperties);
 
-        AutoConfiguredOpenTelemetrySdkBuilder builder =
-            AutoConfiguredOpenTelemetrySdk.builder()
-                .setResultAsGlobal(true)
-                .addPropertiesSupplier(config::getAllProperties);
-
-        ClassLoader classLoader = AgentInitializer.getExtensionsClassLoader();
-        if (classLoader != null) {
-          // May be null in unit tests.
-          builder.setServiceClassLoader(classLoader);
-        }
-
-        OpenTelemetrySdk sdk = builder.build().getOpenTelemetrySdk();
-        OpenTelemetrySdkAccess.internalSetForceFlush(
-            (timeout, unit) -> {
-              CompletableResultCode traceResult = sdk.getSdkTracerProvider().forceFlush();
-              MeterProvider meterProvider = GlobalMeterProvider.get();
-              final CompletableResultCode metricsResult;
-              if (meterProvider instanceof SdkMeterProvider) {
-                metricsResult = ((SdkMeterProvider) meterProvider).forceFlush();
-              } else {
-                metricsResult = CompletableResultCode.ofSuccess();
-              }
-              CompletableResultCode.ofAll(Arrays.asList(traceResult, metricsResult))
-                  .join(timeout, unit);
-            });
-      }
-
-    } else {
-      logger.info("Tracing is disabled.");
+    ClassLoader classLoader = AgentInitializer.getExtensionsClassLoader();
+    if (classLoader != null) {
+      // May be null in unit tests.
+      builder.setServiceClassLoader(classLoader);
     }
+
+    AutoConfiguredOpenTelemetrySdk autoConfiguredSdk = builder.build();
+    OpenTelemetrySdk sdk = autoConfiguredSdk.getOpenTelemetrySdk();
+
+    OpenTelemetrySdkAccess.internalSetForceFlush(
+        (timeout, unit) -> {
+          CompletableResultCode traceResult = sdk.getSdkTracerProvider().forceFlush();
+          MeterProvider meterProvider = GlobalMeterProvider.get();
+          final CompletableResultCode metricsResult;
+          if (meterProvider instanceof SdkMeterProvider) {
+            metricsResult = ((SdkMeterProvider) meterProvider).forceFlush();
+          } else {
+            metricsResult = CompletableResultCode.ofSuccess();
+          }
+          CompletableResultCode.ofAll(Arrays.asList(traceResult, metricsResult))
+              .join(timeout, unit);
+        });
+
+    return autoConfiguredSdk;
   }
 }

javaagent-tooling/src/test/groovy/io/opentelemetry/javaagent/tooling/OpenTelemetryInstallerTest.groovy

@@ -12,7 +12,6 @@ import spock.lang.Specification
 
 class OpenTelemetryInstallerTest extends Specification {
 
-
   void setup() {
     GlobalOpenTelemetry.resetForTest()
   }
@@ -21,40 +20,12 @@ class OpenTelemetryInstallerTest extends Specification {
     GlobalOpenTelemetry.resetForTest()
   }
 
-
-  def "should initialize noop"() {
-
-    given:
-    def config = Config.builder()
-      .readProperties([
-        (OpenTelemetryInstaller.JAVAAGENT_NOOP_CONFIG)   : "true",
-        (OpenTelemetryInstaller.JAVAAGENT_ENABLED_CONFIG): "true"
-      ])
-      .build()
-
+  def "should initialize GlobalOpenTelemetry"() {
     when:
-    def otelInstaller = new OpenTelemetryInstaller()
-    otelInstaller.beforeAgent(config)
-
-    then:
-    GlobalOpenTelemetry.getTracerProvider() == NoopOpenTelemetry.getInstance().getTracerProvider()
-  }
-
-  def "should NOT initialize noop"() {
-
-    given:
-    def config = Config.builder()
-      .readProperties([
-        (OpenTelemetryInstaller.JAVAAGENT_NOOP_CONFIG)   : "true",
-        (OpenTelemetryInstaller.JAVAAGENT_ENABLED_CONFIG): "false"
-      ])
-      .build()
-
-    when:
-    def otelInstaller = new OpenTelemetryInstaller()
-    otelInstaller.beforeAgent(config)
+    def otelInstaller = OpenTelemetryInstaller.installOpenTelemetrySdk(Config.builder().build())
 
     then:
+    otelInstaller != null
     GlobalOpenTelemetry.getTracerProvider() != NoopOpenTelemetry.getInstance().getTracerProvider()
   }