feat: 비동기 스레드에 MDC 데이터 적재

- 비동기 스레드에 요청 스레드의 MDC 데이터를 적재하여 로그 추적이 안되는 문제 해결
- 데코레이터 디자인 패턴 적용

Author: kchsoft

src/main/java/site/praytogether/pray_together/config/AsyncConfig.java

@@ -17,6 +17,7 @@ public Executor notificationExecutor() {
     executor.setQueueCapacity(100);
     executor.setMaxPoolSize(10);
     executor.setThreadNamePrefix("notification-");
+    executor.setTaskDecorator(new MdcTaskDecorator());
     executor.setWaitForTasksToCompleteOnShutdown(true);
     executor.setAwaitTerminationSeconds(30);
     executor.initialize();
@@ -30,6 +31,7 @@ public Executor emailExecutor() {
     executor.setQueueCapacity(50);
     executor.setMaxPoolSize(10);
     executor.setThreadNamePrefix("email-");
+    executor.setTaskDecorator(new MdcTaskDecorator());
     executor.setWaitForTasksToCompleteOnShutdown(true);
     executor.setAwaitTerminationSeconds(60);
     executor.initialize();

src/main/java/site/praytogether/pray_together/config/MdcTaskDecorator.java

@@ -0,0 +1,25 @@
+package site.praytogether.pray_together.config;
+
+import java.util.Map;
+import org.slf4j.MDC;
+import org.springframework.core.task.TaskDecorator;
+import org.springframework.lang.NonNull;
+
+public class MdcTaskDecorator implements TaskDecorator {
+
+  @Override
+  @NonNull
+  public Runnable decorate(@NonNull Runnable runnable) {
+    Map<String, String> contextMap = MDC.getCopyOfContextMap();
+    return () -> {
+      if (contextMap != null) {
+        MDC.setContextMap(contextMap);
+      }
+      try {
+        runnable.run();
+      } finally {
+        MDC.clear();
+      }
+    };
+  }
+}