fix(notification): disable mail health contributor in DlqIntegrationTest

notification-service/src/main/java/com/ecommerce/notification_service/consumer/DeadLetterConsumer.java

@@ -14,7 +14,7 @@ public class DeadLetterConsumer {
      * Consumes messages rejected by the main listener after all retry attempts.
      * Logs a structured ERROR for Loki/Grafana alerting and acks the message.
      */
-    @RabbitListener(queues = RabbitMQConfig.DLQ)
+    @RabbitListener(id = "dlqListener", queues = RabbitMQConfig.DLQ)
     public void consumeDeadLetter(OrderPlacedEvent event) {
         log.error("DEAD_LETTER_RECEIVED: orderReference={}, email={}",
                 event.orderReference(), event.email());

notification-service/src/test/java/com/ecommerce/notification_service/DlqIntegrationTest.java

@@ -4,9 +4,11 @@
 import com.ecommerce.notification_service.event.OrderPlacedEvent;
 import jakarta.mail.Session;
 import jakarta.mail.internet.MimeMessage;
+import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.springframework.amqp.core.Message;
 import org.springframework.amqp.rabbit.core.RabbitTemplate;
+import org.springframework.amqp.rabbit.listener.RabbitListenerEndpointRegistry;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.mail.MailSendException;
@@ -33,8 +35,8 @@
  *   - RabbitMQ  → Testcontainers (real broker; DLX/DLQ declared by Spring context)
  *   - JavaMailSender → @MockitoBean (throws MailSendException on every send)
  *
- * Retry intervals are overridden via @DynamicPropertySource to keep the test fast
- * (2 attempts × ~100 ms intervals instead of the production 3 × 10 s).
+ * The DeadLetterConsumer listener is stopped before the test so messages remain
+ * in the DLQ and can be polled directly via rabbitTemplate.receive().
  */
 @SpringBootTest
 @Testcontainers
@@ -56,8 +58,14 @@ static void configureProperties(DynamicPropertyRegistry registry) {
 
         registry.add("spring.mail.host", () -> "127.0.0.1");
         registry.add("spring.mail.port", () -> "25");
+        // @MockitoBean replaces JavaMailSenderImpl with a mock; the mail health
+        // contributor requires a concrete implementation, so disable it here.
+        registry.add("management.health.mail.enabled", () -> "false");
 
-        // Fast retries so the test doesn't wait ~19 s (production: 3 attempts × 10 s)
+        // Retry is disabled by default in the test classpath application.yaml (which replaces
+        // the production yaml). Explicitly enable it and use fast intervals so the test
+        // exhausts retries quickly instead of waiting ~19 s (production: 3 attempts × 10 s).
+        registry.add("spring.rabbitmq.listener.simple.retry.enabled",          () -> "true");
         registry.add("spring.rabbitmq.listener.simple.retry.max-attempts",     () -> "2");
         registry.add("spring.rabbitmq.listener.simple.retry.initial-interval", () -> "100ms");
         registry.add("spring.rabbitmq.listener.simple.retry.max-interval",     () -> "200ms");
@@ -67,6 +75,18 @@ static void configureProperties(DynamicPropertyRegistry registry) {
     @Autowired
     private RabbitTemplate rabbitTemplate;
 
+    @Autowired
+    private RabbitListenerEndpointRegistry listenerRegistry;
+
+    @BeforeEach
+    void stopDlqConsumer() {
+        // Stop the DeadLetterConsumer listener so messages stay in the DLQ
+        // and can be polled directly. Spring AMQP captures the original bean
+        // reference before any spy/mock wrapper, making spy-based verification
+        // unreliable — polling a paused queue is the reliable alternative.
+        listenerRegistry.getListenerContainer("dlqListener").stop();
+    }
+
     @Test
     void publishOrderEvent_emailAlwaysFails_messageDeadLetters() {
         // Arrange – simulate SMTP rejection after message construction succeeds
@@ -84,7 +104,7 @@ void publishOrderEvent_emailAlwaysFails_messageDeadLetters() {
                 event);
 
         // Assert – wait up to 15 s for the dead-lettered message to appear in the DLQ.
-        // rabbitTemplate.receive() does a non-blocking peek with a 1-second timeout.
+        // The DLQ consumer is stopped so the message stays until we receive it.
         await()
                 .atMost(15, TimeUnit.SECONDS)
                 .pollInterval(500, TimeUnit.MILLISECONDS)