add test for reflection method filtering

Author: SylvainJuge

instrumentation/internal/internal-reflection/javaagent-integration-tests/src/main/java/instrumentation/TestHelperClass.java

@@ -0,0 +1,15 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package instrumentation;
+
+/**
+ * Class that will be injected in target classloader with inline instrumentation and proxied with
+ * indy instrumentation
+ */
+public class TestHelperClass {
+
+  public TestHelperClass() {}
+}

instrumentation/internal/internal-reflection/javaagent-integration-tests/src/main/java/instrumentation/TestInstrumentationModule.java

@@ -10,10 +10,15 @@
 import com.google.auto.service.AutoService;
 import io.opentelemetry.javaagent.extension.instrumentation.InstrumentationModule;
 import io.opentelemetry.javaagent.extension.instrumentation.TypeInstrumentation;
+import io.opentelemetry.javaagent.extension.instrumentation.internal.ExperimentalInstrumentationModule;
+import io.opentelemetry.javaagent.extension.instrumentation.internal.injection.ClassInjector;
+import io.opentelemetry.javaagent.extension.instrumentation.internal.injection.InjectionMode;
+import java.util.Arrays;
 import java.util.List;
 
 @AutoService(InstrumentationModule.class)
-public class TestInstrumentationModule extends InstrumentationModule {
+public class TestInstrumentationModule extends InstrumentationModule
+    implements ExperimentalInstrumentationModule {
   public TestInstrumentationModule() {
     super("test-instrumentation");
   }
@@ -22,4 +27,17 @@ public TestInstrumentationModule() {
   public List<TypeInstrumentation> typeInstrumentations() {
     return singletonList(new TestTypeInstrumentation());
   }
+
+  @Override
+  public List<String> getAdditionalHelperClassNames() {
+    // makes the class from instrumentation from the instrumented class with inlined advice
+    return Arrays.asList("instrumentation.TestHelperClass");
+  }
+
+  @Override
+  public void injectClasses(ClassInjector injector) {
+    injector
+        .proxyBuilder("instrumentation.TestHelperClass")
+        .inject(InjectionMode.CLASS_AND_RESOURCE);
+  }
 }

instrumentation/internal/internal-reflection/javaagent-integration-tests/src/test/java/ReflectionTest.java

@@ -5,6 +5,8 @@
 
 import static org.assertj.core.api.Assertions.assertThat;
 
+import instrumentation.TestHelperClass;
+import io.opentelemetry.javaagent.bootstrap.IndyProxy;
 import io.opentelemetry.javaagent.bootstrap.VirtualFieldAccessorMarker;
 import io.opentelemetry.javaagent.bootstrap.VirtualFieldInstalledMarker;
 import java.io.ObjectStreamClass;
@@ -42,7 +44,37 @@ void testOurFieldsAndMethodsAreNotVisibleWithReflection() {
   void testGeneratedSerialVersionUid() {
     // expected value is computed with serialver utility that comes with jdk
     assertThat(ObjectStreamClass.lookup(TestClass.class).getSerialVersionUID())
-        .isEqualTo(-1508684692096503670L);
+        .isEqualTo(-4292813100633930936L);
     assertThat(TestClass.class.getDeclaredFields().length).isEqualTo(0);
   }
+
+  @Test
+  void testInjectedClassProxyUnwrap() throws Exception {
+    TestClass testClass = new TestClass();
+    Class<?> helperType = testClass.testHelperClass();
+    assertThat(helperType)
+        .describedAs("unable to resolve injected class from instrumented class")
+        .isNotNull();
+
+    Object instance = helperType.getConstructor().newInstance();
+    if (IndyProxy.class.isAssignableFrom(helperType)) {
+      // indy advice: must be an indy proxy
+
+      for (Method method : helperType.getMethods()) {
+        assertThat(method.getName())
+            .describedAs("proxy method must be hidden from reflection")
+            .isNotEqualTo("__getIndyProxyDelegate");
+      }
+
+      assertThat(instance).isInstanceOf(IndyProxy.class);
+
+      Object proxyDelegate = ((IndyProxy) instance).__getIndyProxyDelegate();
+      assertThat(proxyDelegate).isNotInstanceOf(IndyProxy.class);
+
+    } else {
+      // inline advice: must be of the expected type
+      assertThat(helperType).isEqualTo(TestHelperClass.class);
+      assertThat(instance).isInstanceOf(TestHelperClass.class).isNotInstanceOf(IndyProxy.class);
+    }
+  }
 }

instrumentation/internal/internal-reflection/javaagent-integration-tests/src/test/java/TestClass.java

@@ -17,4 +17,13 @@ public String testMethod() {
   public String testMethod2() {
     return "not instrumented";
   }
+
+  public Class<?> testHelperClass() {
+    try {
+      return Class.forName(
+          "instrumentation.TestHelperClass", false, TestClass.class.getClassLoader());
+    } catch (ClassNotFoundException e) {
+      return null;
+    }
+  }
 }