CAMEL-22717: camel-mdc - MDC is lost when using interceptSendToEndpoint (and potentially other situations)

Author: davsclaus

components/camel-mdc/src/main/java/org/apache/camel/mdc/MDCEventNotifier.java

@@ -24,22 +24,31 @@ class MDCEventNotifier extends SimpleEventNotifierSupport {
     private final MDCService mdc;
 
     public MDCEventNotifier(MDCService mdc) {
-        // ignore these
+        this.mdc = mdc;
+    }
+
+    @Override
+    protected void setupIgnore(boolean ignore) {
         setIgnoreCamelContextEvents(true);
         setIgnoreCamelContextInitEvents(true);
         setIgnoreRouteEvents(true);
         setIgnoreServiceEvents(true);
         setIgnoreStepEvents(true);
         // we need also async processing started events
         setIgnoreExchangeAsyncProcessingStartedEvents(false);
-        this.mdc = mdc;
     }
 
     @Override
     public void notify(CamelEvent event) throws Exception {
         if (event instanceof CamelEvent.ExchangeAsyncProcessingStartedEvent eap) {
             // exchange is continued processed on another thread so unset MDC
             mdc.unsetMDC(eap.getExchange());
+        } else if (event instanceof CamelEvent.ExchangeCompletedEvent ec) {
+            // exchange is completed so unset MDC
+            mdc.unsetMDC(ec.getExchange());
+        } else if (event instanceof CamelEvent.ExchangeFailedEvent ef) {
+            // exchange is failed so unset MDC
+            mdc.unsetMDC(ef.getExchange());
         }
     }
 }

components/camel-mdc/src/test/resources/log4j2.properties

@@ -27,4 +27,4 @@ appender.file.layout.type = PatternLayout
 appender.file.layout.pattern = %d [%-15.15t] %-5p %-30.30c{1} - %m [%X{camel.threadId}, %X{camel.contextId}, %X{camel.routeId}, %X{camel.exchangeId}, %X{camel.messageId}, %X{head1}, %X{prop1}, %X{head2}, %X{prop2}]%n
 
 rootLogger.level = INFO
-rootLogger.appenderRef.file.ref = console
+rootLogger.appenderRef.file.ref = file