Fix double log capture (#299)

open-telemetry · Apr 1, 2020 · 10d93ac · 10d93ac
1 parent 64b9585
commit 10d93ac
Showing 1 changed file with 15 additions and 2 deletions.
diff --git a/...main/java/io/opentelemetry/auto/instrumentation/log4j/v2_0/Log4jSpansInstrumentation.java b/...main/java/io/opentelemetry/auto/instrumentation/log4j/v2_0/Log4jSpansInstrumentation.java
@@ -85,12 +85,25 @@ public Map<? extends ElementMatcher<? super MethodDescription>, String> transfor
   public static class LogMessageAdvice {
 
     @Advice.OnMethodEnter(suppress = Throwable.class)
-    public static void methodEnter(
+    public static boolean methodEnter(
         @Advice.This final Logger logger,
         @Advice.Argument(1) final Level level,
         @Advice.Argument(3) final Message message,
         @Advice.Argument(4) final Throwable t) {
-      Log4jSpans.capture(logger, level, message, t);
+      // need to track call depth across all loggers in order to avoid double capture when one
+      // logging framework delegates to another
+      final boolean topLevel = CallDepthThreadLocalMap.incrementCallDepth("logger") == 0;
+      if (topLevel) {
+        Log4jSpans.capture(logger, level, message, t);
+      }
+      return topLevel;
+    }
+
+    @Advice.OnMethodExit(onThrowable = Throwable.class, suppress = Throwable.class)
+    public static void methodExit(@Advice.Enter final boolean topLevel) {
+      if (topLevel) {
+        CallDepthThreadLocalMap.reset("logger");
+      }
     }
   }