try reproduce MDC issue

doc-examples/jdbc-example-java/src/main/java/example/ProductManager.java

@@ -1,14 +1,23 @@
 
 package example;
 
+import io.micronaut.context.propagation.slf4j.MdcPropagationContext;
+import io.micronaut.core.propagation.PropagatedContext;
 import io.micronaut.transaction.TransactionOperations;
+import io.micronaut.transaction.annotation.Transactional;
 import jakarta.inject.Singleton;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.slf4j.MDC;
+
 import java.sql.Connection;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
+import java.util.UUID;
 
 @Singleton
 public class ProductManager {
+    private static final Logger LOG = LoggerFactory.getLogger(ProductManager.class);
 
     private final Connection connection;
     private final TransactionOperations<Connection> transactionManager;
@@ -72,4 +81,51 @@ Product findUsingRepo(String name) {
             return productRepository.findByName(name).orElse(null);
         });
     }
+
+    /**
+     * Creates new product using transaction operations and product repository.
+     *
+     * @param name the product name
+     * @param manufacturer the manufacturer
+     * @return the created product instance
+     */
+    Product saveUsingRepoAndMDC(String name, Manufacturer manufacturer) {
+        UUID newUserId = UUID.randomUUID();
+        MDC.put("userId", newUserId.toString());
+        MDC.put("product", name);
+        try (PropagatedContext.Scope ignore = PropagatedContext.getOrEmpty().plus(new MdcPropagationContext()).propagate()) {
+            return transactionManager.executeWrite(status -> {
+                String product = MDC.get("product");
+                LOG.info("Saving product {}", product);
+                return productRepository.save(new Product(name, manufacturer));
+            });
+        }
+    }
+
+    /**
+     * Creates new product using transaction operations and product repository.
+     *
+     * @param name the product name
+     * @param manufacturer the manufacturer
+     * @return the created product instance
+     */
+    Product saveUsingRepoAndMDCTransactional(String name, Manufacturer manufacturer) {
+        UUID newUserId = UUID.randomUUID();
+        MDC.put("userId", newUserId.toString());
+        MDC.put("product", name);
+        try (PropagatedContext.Scope ignore = PropagatedContext.getOrEmpty().plus(new MdcPropagationContext()).propagate()) {
+            Product product = saveProductTransactional(name, manufacturer);
+            System.out.println("MDC.get(\"another\") = " + MDC.get("another"));
+            return product;
+        }
+    }
+
+    @Transactional
+    Product saveProductTransactional(String name, Manufacturer manufacturer) {
+        String product = MDC.get("product");
+        LOG.info("Saving product {}", product);
+        MDC.put("another", product);
+        return productRepository.save(new Product(name, manufacturer));
+    }
+
 }

doc-examples/jdbc-example-java/src/main/resources/logback.xml

@@ -2,7 +2,7 @@
 
     <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
         <encoder>
-            <pattern>%cyan(%d{HH:mm:ss.SSS}) %gray([%thread]) %highlight(%-5level) %magenta(%logger{36}) - %msg%n</pattern>
+            <pattern>product=%X{product} %cyan(%d{HH:mm:ss.SSS}) %gray([%thread]) %highlight(%-5level) %magenta(%logger{36}) - %msg%n</pattern>
         </encoder>
     </appender>
 

doc-examples/jdbc-example-java/src/test/java/example/ProductManagerSpec.java

@@ -49,4 +49,16 @@ void testProductManagerUsingRepo() {
         assertNull(product);
     }
 
+    @Test
+    void testProductManagerUsingRepoMDC() {
+        Manufacturer intel = manufacturerRepository.save("Intel");
+        productManager.saveUsingRepoAndMDCTransactional("Processor", intel);
+
+        Product product = productManager.findUsingRepo("Processor");
+        assertEquals("Processor", product.getName());
+
+        product = productManager.findUsingRepo("NonExistingProduct");
+        assertNull(product);
+    }
+
 }