InstrumentationModule cleanup (#2925)

instrumentation/methods/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/methods/MethodInstrumentationModule.java

@@ -55,7 +55,7 @@ public class MethodInstrumentationModule extends InstrumentationModule {
   // the default configuration has empty "otel.instrumentation.methods.include", and so doesn't
   // generate any TypeInstrumentation for muzzle to analyze
   @Override
-  protected String[] getMuzzleHelperClassNames() {
+  public String[] getMuzzleHelperClassNames() {
     return typeInstrumentations.isEmpty()
         ? new String[0]
         : new String[] {"io.opentelemetry.javaagent.instrumentation.methods.MethodTracer"};

javaagent-extension-api/src/main/java/io/opentelemetry/javaagent/extension/instrumentation/InstrumentationModule.java

@@ -33,12 +33,12 @@ import net.bytebuddy.matcher.ElementMatcher;
  */
 public abstract class InstrumentationModule implements AgentExtension {
   private static final String[] EMPTY = new String[0];
+  private static final Reference[] EMPTY_REFS = new Reference[0];
 
   private static final boolean DEFAULT_ENABLED =
       Config.get().getBooleanProperty("otel.instrumentation.common.default-enabled", true);
 
   private final Set<String> instrumentationNames;
-  final boolean enabled;
 
   /**
    * Creates an instrumentation module. Note that all implementations of {@link
@@ -75,7 +75,6 @@ public abstract class InstrumentationModule implements AgentExtension {
       throw new IllegalArgumentException("InstrumentationModules must be named");
     }
     this.instrumentationNames = new LinkedHashSet<>(instrumentationNames);
-    this.enabled = Config.get().isInstrumentationEnabled(instrumentationNames, defaultEnabled());
   }
 
   private static List<String> toList(String first, String[] rest) {
@@ -101,15 +100,17 @@ public abstract class InstrumentationModule implements AgentExtension {
     return instrumentationNames.iterator().next();
   }
 
+  /** Returns true if this instrumentation module should be installed. */
+  public final boolean isEnabled() {
+    return Config.get().isInstrumentationEnabled(instrumentationNames, defaultEnabled());
+  }
+
   /**
-   * Returns all helper classes that will be injected into the application classloader, both ones
+   * Allows instrumentation modules to disable themselves by default, or to additionally disable
-   * provided by the implementation and ones that were collected by muzzle during compilation.
+   * themselves on some other condition.
    */
-  public final List<String> getAllHelperClassNames() {
+  protected boolean defaultEnabled() {
-    List<String> helperClassNames = new ArrayList<>();
+    return DEFAULT_ENABLED;
-    helperClassNames.addAll(asList(additionalHelperClassNames()));
-    helperClassNames.addAll(asList(getMuzzleHelperClassNames()));
-    return helperClassNames;
   }
 
   /**
@@ -127,83 +128,6 @@ public abstract class InstrumentationModule implements AgentExtension {
     return false;
   }
 
-  /**
-   * Returns a list of references to helper and library classes used in this module's type
-   * instrumentation advices.
-   *
-   * <p>The actual implementation of this method is generated automatically during compilation by
-   * the {@code io.opentelemetry.javaagent.tooling.muzzle.collector.MuzzleCodeGenerationPlugin}
-   * ByteBuddy plugin.
-   *
-   * <p><b>This method is generated automatically</b>: if you override it, the muzzle compile plugin
-   * will not generate a new implementation, it will leave the existing one.
-   */
-  public Reference[] getMuzzleReferences() {
-    return new Reference[0];
-  }
-
-  /**
-   * Returns a list of instrumentation helper classes, automatically detected by muzzle during
-   * compilation. Those helpers will be injected into the application classloader.
-   *
-   * <p>The actual implementation of this method is generated automatically during compilation by
-   * the {@code io.opentelemetry.javaagent.tooling.muzzle.collector.MuzzleCodeGenerationPlugin}
-   * ByteBuddy plugin.
-   *
-   * <p><b>This method is generated automatically</b>: if you override it, the muzzle compile plugin
-   * will not generate a new implementation, it will leave the existing one.
-   */
-  protected String[] getMuzzleHelperClassNames() {
-    return EMPTY;
-  }
-
-  /**
-   * Returns a map of {@code class-name to context-class-name}. Keys (and their subclasses) will be
-   * associated with a context class stored in the value.
-   *
-   * <p>The actual implementation of this method is generated automatically during compilation by
-   * the {@code io.opentelemetry.javaagent.tooling.muzzle.collector.MuzzleCodeGenerationPlugin}
-   * ByteBuddy plugin.
-   *
-   * <p><b>This method is generated automatically</b>: if you override it, the muzzle compile plugin
-   * will not generate a new implementation, it will leave the existing one.
-   */
-  protected Map<String, String> getMuzzleContextStoreClasses() {
-    return Collections.emptyMap();
-  }
-
-  /**
-   * Instrumentation modules can override this method to provide additional helper classes that are
-   * not located in instrumentation packages described in the {@code InstrumentationClassPredicate}
-   * class and {@link #isHelperClass(String)} (and not automatically detected by muzzle). These
-   * additional classes will be injected into the application classloader first.
-   *
-   * <p>Implementing {@link #isHelperClass(String)} is generally simpler and less error-prone
-   * compared to implementing this method.
-   *
-   * @deprecated Use {@link #isHelperClass(String)} instead.
-   */
-  @Deprecated
-  protected String[] additionalHelperClassNames() {
-    return EMPTY;
-  }
-
-  /**
-   * Same as {@link #order()}.
-   *
-   * @deprecated use {@link #order()} instead.
-   */
-  @Deprecated
-  public int getOrder() {
-    return 0;
-  }
-
-  /** {@inheritDoc} */
-  @Override
-  public int order() {
-    return getOrder();
-  }
-
   /** Returns resource names to inject into the user's classloader. */
   public String[] helperResourceNames() {
     return EMPTY;
@@ -228,10 +152,47 @@ public abstract class InstrumentationModule implements AgentExtension {
   public abstract List<TypeInstrumentation> typeInstrumentations();
 
   /**
-   * Allows instrumentation modules to disable themselves by default, or to additionally disable
+   * Returns a list of references to helper and library classes used in this module's type
-   * themselves on some other condition.
+   * instrumentation advices.
+   *
+   * <p>The actual implementation of this method is generated automatically during compilation by
+   * the {@code io.opentelemetry.javaagent.tooling.muzzle.collector.MuzzleCodeGenerationPlugin}
+   * ByteBuddy plugin.
+   *
+   * <p><b>This method is generated automatically</b>: if you override it, the muzzle compile plugin
+   * will not generate a new implementation, it will leave the existing one.
    */
-  protected boolean defaultEnabled() {
+  public Reference[] getMuzzleReferences() {
-    return DEFAULT_ENABLED;
+    return EMPTY_REFS;
+  }
+
+  /**
+   * Returns a list of instrumentation helper classes, automatically detected by muzzle during
+   * compilation. Those helpers will be injected into the application classloader.
+   *
+   * <p>The actual implementation of this method is generated automatically during compilation by
+   * the {@code io.opentelemetry.javaagent.tooling.muzzle.collector.MuzzleCodeGenerationPlugin}
+   * ByteBuddy plugin.
+   *
+   * <p><b>This method is generated automatically</b>: if you override it, the muzzle compile plugin
+   * will not generate a new implementation, it will leave the existing one.
+   */
+  public String[] getMuzzleHelperClassNames() {
+    return EMPTY;
+  }
+
+  /**
+   * Returns a map of {@code class-name to context-class-name}. Keys (and their subclasses) will be
+   * associated with a context class stored in the value.
+   *
+   * <p>The actual implementation of this method is generated automatically during compilation by
+   * the {@code io.opentelemetry.javaagent.tooling.muzzle.collector.MuzzleCodeGenerationPlugin}
+   * ByteBuddy plugin.
+   *
+   * <p><b>This method is generated automatically</b>: if you override it, the muzzle compile plugin
+   * will not generate a new implementation, it will leave the existing one.
+   */
+  public Map<String, String> getMuzzleContextStoreClasses() {
+    return Collections.emptyMap();
   }
 }

javaagent-extension-api/src/main/java/io/opentelemetry/javaagent/extension/matcher/AgentElementMatchers.java

@@ -16,7 +16,7 @@ import net.bytebuddy.matcher.ElementMatcher;
 /**
  * This class provides some custom ByteBuddy element matchers to use when applying instrumentation.
  */
-public class AgentElementMatchers {
+public final class AgentElementMatchers {
 
   public static ElementMatcher.Junction<TypeDescription> extendsClass(
       ElementMatcher<TypeDescription> matcher) {
@@ -92,4 +92,6 @@ public class AgentElementMatchers {
       }
     }
   }
+
+  private AgentElementMatchers() {}
 }

javaagent-extension-api/src/main/java/io/opentelemetry/javaagent/extension/matcher/NameMatchers.java

@@ -74,4 +74,6 @@ public final class NameMatchers {
       return (include && contained) || (!include && !contained);
     }
   }
+
+  private NameMatchers() {}
 }

javaagent-extension-api/src/main/java/io/opentelemetry/javaagent/spi/ByteBuddyAgentCustomizer.java

@@ -1,34 +0,0 @@
-/*
- * Copyright The OpenTelemetry Authors
- * SPDX-License-Identifier: Apache-2.0
- */
-
-package io.opentelemetry.javaagent.spi;
-
-import io.opentelemetry.javaagent.extension.spi.AgentExtension;
-import java.lang.instrument.Instrumentation;
-import net.bytebuddy.agent.builder.AgentBuilder;
-
-/**
- * {@link ByteBuddyAgentCustomizer} customizes ByteBuddy agent builder right before the agent is
- * installed - {@link AgentBuilder#installOn(Instrumentation)}. This SPI can be used to customize
- * {@link AgentBuilder} for vendor specific needs. For example install custom listeners or exclude
- * classes. Use this SPI carefully because it can change {@link net.bytebuddy.ByteBuddy} behaviour.
- *
- * <p>This is a service provider interface that requires implementations to be registered in {@code
- * META-INF/services} folder.
- *
- * @deprecated Use {@link AgentExtension} with correct {@link AgentExtension#order()} instead.
- */
-@Deprecated
-public interface ByteBuddyAgentCustomizer {
-
-  /**
-   * Customize ByteBuddy agent builder before {@link AgentBuilder#installOn(Instrumentation)} is
-   * called.
-   *
-   * @param agentBuilder ByteBuddy agent from {@code AgentInstaller}.
-   * @return customized agent builder.
-   */
-  AgentBuilder customize(AgentBuilder agentBuilder);
-}

javaagent-tooling/src/main/java/io/opentelemetry/javaagent/extension/instrumentation/ActualInstrumentationExtensionImplementation.java

@@ -49,11 +49,11 @@ public final class ActualInstrumentationExtensionImplementation
   @Override
   AgentBuilder extend(
       InstrumentationModule instrumentationModule, AgentBuilder parentAgentBuilder) {
-    if (!instrumentationModule.enabled) {
+    if (!instrumentationModule.isEnabled()) {
       log.debug("Instrumentation {} is disabled", instrumentationModule.extensionName());
       return parentAgentBuilder;
     }
-    List<String> helperClassNames = instrumentationModule.getAllHelperClassNames();
+    List<String> helperClassNames = asList(instrumentationModule.getMuzzleHelperClassNames());
     List<String> helperResourceNames = asList(instrumentationModule.helperResourceNames());
     List<TypeInstrumentation> typeInstrumentations = instrumentationModule.typeInstrumentations();
     if (typeInstrumentations.isEmpty()) {
@@ -68,7 +68,7 @@ public final class ActualInstrumentationExtensionImplementation
 
     ElementMatcher.Junction<ClassLoader> moduleClassLoaderMatcher =
         instrumentationModule.classLoaderMatcher();
-    MuzzleMatcher muzzleMatcher = new MuzzleMatcher(instrumentationModule);
+    MuzzleMatcher muzzleMatcher = new MuzzleMatcher(instrumentationModule, helperClassNames);
     AgentBuilder.Transformer helperInjector =
         new HelperInjector(
             instrumentationModule.extensionName(), helperClassNames, helperResourceNames);
@@ -135,11 +135,14 @@ public final class ActualInstrumentationExtensionImplementation
    */
   private static class MuzzleMatcher implements AgentBuilder.RawMatcher {
     private final InstrumentationModule instrumentationModule;
+    private final List<String> helperClassNames;
     private final AtomicBoolean initialized = new AtomicBoolean(false);
     private volatile ReferenceMatcher referenceMatcher;
 
-    private MuzzleMatcher(InstrumentationModule instrumentationModule) {
+    private MuzzleMatcher(
+        InstrumentationModule instrumentationModule, List<String> helperClassNames) {
       this.instrumentationModule = instrumentationModule;
+      this.helperClassNames = helperClassNames;
     }
 
     @Override
@@ -185,7 +188,7 @@ public final class ActualInstrumentationExtensionImplementation
       if (initialized.compareAndSet(false, true)) {
         referenceMatcher =
             new ReferenceMatcher(
-                instrumentationModule.getAllHelperClassNames(),
+                helperClassNames,
                 instrumentationModule.getMuzzleReferences(),
                 instrumentationModule::isHelperClass);
       }

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

@@ -20,7 +20,6 @@ import io.opentelemetry.javaagent.extension.spi.AgentExtension;
 import io.opentelemetry.javaagent.instrumentation.api.SafeServiceLoader;
 import io.opentelemetry.javaagent.instrumentation.api.internal.BootstrapPackagePrefixesHolder;
 import io.opentelemetry.javaagent.spi.BootstrapPackagesProvider;
-import io.opentelemetry.javaagent.spi.ByteBuddyAgentCustomizer;
 import io.opentelemetry.javaagent.spi.ComponentInstaller;
 import io.opentelemetry.javaagent.spi.IgnoreMatcherProvider;
 import io.opentelemetry.javaagent.tooling.config.ConfigInitializer;
@@ -170,7 +169,6 @@ public class AgentInstaller {
       }
     }
 
-    agentBuilder = customizeByteBuddyAgent(agentBuilder);
     log.debug("Installed {} instrumenter(s)", numInstrumenters);
     ResettableClassFileTransformer resettableClassFileTransformer = agentBuilder.installOn(inst);
     installComponentsAfterByteBuddy(componentInstallers, config);
@@ -221,15 +219,6 @@ public class AgentInstaller {
     }
   }
 
-  private static AgentBuilder customizeByteBuddyAgent(AgentBuilder agentBuilder) {
-    Iterable<ByteBuddyAgentCustomizer> agentCustomizers = loadByteBuddyAgentCustomizers();
-    for (ByteBuddyAgentCustomizer agentCustomizer : agentCustomizers) {
-      log.debug("Applying agent builder customizer {}", agentCustomizer.getClass().getName());
-      agentBuilder = agentCustomizer.customize(agentBuilder);
-    }
-    return agentBuilder;
-  }
-
   private static Iterable<ComponentInstaller> loadComponentProviders() {
     return ServiceLoader.load(ComponentInstaller.class, AgentInstaller.class.getClassLoader());
   }
@@ -245,11 +234,6 @@ public class AgentInstaller {
     return new NoopIgnoreMatcherProvider();
   }
 
-  private static Iterable<ByteBuddyAgentCustomizer> loadByteBuddyAgentCustomizers() {
-    return ServiceLoader.load(
-        ByteBuddyAgentCustomizer.class, AgentInstaller.class.getClassLoader());
-  }
-
   private static List<? extends AgentExtension> loadAgentExtensions() {
     // TODO: InstrumentationModule should no longer be an SPI
     Stream<? extends AgentExtension> extensions =

javaagent-tooling/src/main/java/io/opentelemetry/javaagent/tooling/muzzle/collector/MuzzleCodeGenerator.java

@@ -195,7 +195,7 @@ class MuzzleCodeGenerator implements AsmVisitorWrapper {
 
     private void generateMuzzleHelperClassNamesMethod(ReferenceCollector collector) {
       /*
-       * protected String[] getMuzzleHelperClassNames() {
+       * public String[] getMuzzleHelperClassNames() {
        *   return new String[] {
        *     // sorted helper class names
        *   };
@@ -203,7 +203,7 @@ class MuzzleCodeGenerator implements AsmVisitorWrapper {
        */
       MethodVisitor mv =
           super.visitMethod(
-              Opcodes.ACC_PROTECTED,
+              Opcodes.ACC_PUBLIC,
               MUZZLE_HELPER_CLASSES_METHOD_NAME,
               "()[Ljava/lang/String;",
               null,
@@ -236,7 +236,7 @@ class MuzzleCodeGenerator implements AsmVisitorWrapper {
 
     private void generateMuzzleReferencesMethod(ReferenceCollector collector) {
       /*
-       * protected synchronized Reference[] getMuzzleReferences() {
+       * public synchronized Reference[] getMuzzleReferences() {
        *   if (null == this.muzzleReferences) {
        *     this.muzzleReferences = new Reference[] {
        *                               // reference builders
@@ -248,7 +248,7 @@ class MuzzleCodeGenerator implements AsmVisitorWrapper {
       try {
         MethodVisitor mv =
             super.visitMethod(
-                Opcodes.ACC_PROTECTED + Opcodes.ACC_SYNCHRONIZED,
+                Opcodes.ACC_PUBLIC + Opcodes.ACC_SYNCHRONIZED,
                 MUZZLE_REFERENCES_METHOD_NAME,
                 "()[Lio/opentelemetry/javaagent/extension/muzzle/Reference;",
                 null,
@@ -534,7 +534,7 @@ class MuzzleCodeGenerator implements AsmVisitorWrapper {
 
     private void generateMuzzleContextStoreClassesMethod(ReferenceCollector collector) {
       /*
-       * protected Map<String, String> getMuzzleContextStoreClasses() {
+       * public Map<String, String> getMuzzleContextStoreClasses() {
        *   Map<String, String> contextStore = new HashMap();
        *   contextStore.put(..., ...);
        *   return contextStore;
@@ -542,7 +542,7 @@ class MuzzleCodeGenerator implements AsmVisitorWrapper {
        */
       MethodVisitor mv =
           super.visitMethod(
-              Opcodes.ACC_PROTECTED,
+              Opcodes.ACC_PUBLIC,
               MUZZLE_CONTEXT_STORE_CLASSES_METHOD_NAME,
               "()Ljava/util/Map;",
               null,

javaagent-tooling/src/main/java/io/opentelemetry/javaagent/tooling/muzzle/matcher/MuzzleGradlePluginUtil.java

@@ -5,6 +5,8 @@
 
 package io.opentelemetry.javaagent.tooling.muzzle.matcher;
 
+import static java.util.Arrays.asList;
+
 import io.opentelemetry.javaagent.extension.instrumentation.InstrumentationModule;
 import io.opentelemetry.javaagent.extension.muzzle.Reference;
 import io.opentelemetry.javaagent.tooling.HelperInjector;
@@ -49,7 +51,7 @@ public final class MuzzleGradlePluginUtil {
         ServiceLoader.load(InstrumentationModule.class, agentClassLoader)) {
       ReferenceMatcher muzzle =
           new ReferenceMatcher(
-              instrumentationModule.getAllHelperClassNames(),
+              asList(instrumentationModule.getMuzzleHelperClassNames()),
               instrumentationModule.getMuzzleReferences(),
               instrumentationModule::isHelperClass);
       List<Mismatch> mismatches = muzzle.getMismatchedReferenceSources(userClassLoader);
@@ -88,7 +90,7 @@ public final class MuzzleGradlePluginUtil {
           ServiceLoader.load(InstrumentationModule.class, agentClassLoader)) {
         try {
           // verify helper injector works
-          List<String> allHelperClasses = instrumentationModule.getAllHelperClassNames();
+          List<String> allHelperClasses = asList(instrumentationModule.getMuzzleHelperClassNames());
           if (!allHelperClasses.isEmpty()) {
             new HelperInjector(
                     MuzzleGradlePluginUtil.class.getSimpleName(),

testing/agent-exporter/src/main/java/io/opentelemetry/javaagent/testing/bytebuddy/TestAgentExtension.java

@@ -6,13 +6,19 @@
 package io.opentelemetry.javaagent.testing.bytebuddy;
 
 import com.google.auto.service.AutoService;
-import io.opentelemetry.javaagent.spi.ByteBuddyAgentCustomizer;
+import io.opentelemetry.javaagent.extension.spi.AgentExtension;
 import net.bytebuddy.agent.builder.AgentBuilder;
 
-@AutoService(ByteBuddyAgentCustomizer.class)
+@AutoService(AgentExtension.class)
-public class TestByteBuddyAgentCustomizer implements ByteBuddyAgentCustomizer {
+public class TestAgentExtension implements AgentExtension {
+
   @Override
-  public AgentBuilder customize(AgentBuilder agentBuilder) {
+  public AgentBuilder extend(AgentBuilder agentBuilder) {
     return agentBuilder.with(TestAgentListener.INSTANCE);
   }
+
+  @Override
+  public String extensionName() {
+    return "test";
+  }
 }