Extended attributes support for log4j-appender-2.17

instrumentation/log4j/log4j-appender-2.17/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/log4j/appender/v2_17/Log4jHelper.java

@@ -30,7 +30,7 @@
 
 public final class Log4jHelper {
 
-  private static final LogEventMapper<Map<String, String>> mapper;
+  private static final LogEventMapper<Map<String, ?>> mapper;
   private static final boolean captureExperimentalAttributes;
   private static final MethodHandle stackTraceMethodHandle = getStackTraceMethodHandle();
 
@@ -147,17 +147,17 @@ private static MethodHandle getStackTraceMethodHandle() {
     }
   }
 
-  private enum ContextDataAccessorImpl implements ContextDataAccessor<Map<String, String>> {
+  private enum ContextDataAccessorImpl implements ContextDataAccessor<Map<String, ?>, Object> {
     INSTANCE;
 
     @Override
     @Nullable
-    public String getValue(Map<String, String> contextData, String key) {
+    public Object getValue(Map<String, ?> contextData, String key) {
       return contextData.get(key);
     }
 
     @Override
-    public void forEach(Map<String, String> contextData, BiConsumer<String, String> action) {
+    public void forEach(Map<String, ?> contextData, BiConsumer<String, Object> action) {
       contextData.forEach(action);
     }
   }

instrumentation/log4j/log4j-appender-2.17/library/build.gradle.kts

@@ -7,6 +7,7 @@ dependencies {
   annotationProcessor("org.apache.logging.log4j:log4j-core:2.17.0")
 
   implementation(project(":instrumentation:log4j:log4j-context-data:log4j-context-data-2.17:library-autoconfigure"))
+  implementation("io.opentelemetry:opentelemetry-api-incubator")
 
   testImplementation("io.opentelemetry:opentelemetry-sdk-testing")
   testLibrary("com.lmax:disruptor:3.3.4")

instrumentation/log4j/log4j-appender-2.17/library/src/main/java/io/opentelemetry/instrumentation/log4j/appender/v2_17/OpenTelemetryAppender.java

@@ -300,11 +300,13 @@ private void emit(OpenTelemetry openTelemetry, LogEvent event) {
     // when using async logger we'll be executing on a different thread than what started logging
     // reconstruct the context from context data
     if (context == Context.root()) {
-      ContextDataAccessor<ReadOnlyStringMap> contextDataAccessor = ContextDataAccessorImpl.INSTANCE;
-      String traceId = contextDataAccessor.getValue(contextData, ContextDataKeys.TRACE_ID_KEY);
-      String spanId = contextDataAccessor.getValue(contextData, ContextDataKeys.SPAN_ID_KEY);
+      ContextDataAccessor<ReadOnlyStringMap, Object> contextDataAccessor =
+          ContextDataAccessorImpl.INSTANCE;
+      String traceId =
+          contextDataAccessor.getStringValue(contextData, ContextDataKeys.TRACE_ID_KEY);
+      String spanId = contextDataAccessor.getStringValue(contextData, ContextDataKeys.SPAN_ID_KEY);
       String traceFlags =
-          contextDataAccessor.getValue(contextData, ContextDataKeys.TRACE_FLAGS_KEY);
+          contextDataAccessor.getStringValue(contextData, ContextDataKeys.TRACE_FLAGS_KEY);
       if (traceId != null && spanId != null && traceFlags != null) {
         context =
             Context.root()
@@ -340,17 +342,17 @@ private void emit(OpenTelemetry openTelemetry, LogEvent event) {
     builder.emit();
   }
 
-  private enum ContextDataAccessorImpl implements ContextDataAccessor<ReadOnlyStringMap> {
+  private enum ContextDataAccessorImpl implements ContextDataAccessor<ReadOnlyStringMap, Object> {
     INSTANCE;
 
     @Override
     @Nullable
-    public String getValue(ReadOnlyStringMap contextData, String key) {
+    public Object getValue(ReadOnlyStringMap contextData, String key) {
       return contextData.getValue(key);
     }
 
     @Override
-    public void forEach(ReadOnlyStringMap contextData, BiConsumer<String, String> action) {
+    public void forEach(ReadOnlyStringMap contextData, BiConsumer<String, Object> action) {
       contextData.forEach(action::accept);
     }
   }

instrumentation/log4j/log4j-appender-2.17/library/src/main/java/io/opentelemetry/instrumentation/log4j/appender/v2_17/internal/ContextDataAccessor.java

@@ -12,10 +12,18 @@
  * This class is internal and is hence not for public use. Its APIs are unstable and can change at
  * any time.
  */
-public interface ContextDataAccessor<T> {
+public interface ContextDataAccessor<T, V> {
 
   @Nullable
-  String getValue(T contextData, String key);
+  V getValue(T contextData, String key);
 
-  void forEach(T contextData, BiConsumer<String, String> action);
+  default String getStringValue(T contextData, String key) {
+    Object value = getValue(contextData, key);
+    if (value != null) {
+      return value.toString();
+    }
+    return null;
+  }
+
+  void forEach(T contextData, BiConsumer<String, V> action);
 }