From: Kai Moritz <kai@juplo.de>
Date: Thu, 15 May 2025 21:36:38 +0000 (+0200)
Subject: DLT für den auf Message-Conversion basierenden `@KafkaHandler`-Consumer konfiguriert
X-Git-Tag: spring/spring-consumer--messageconverter--dlt--2025-05-lvm--spickzettel~1
X-Git-Url: http://juplo.de/gitweb/?a=commitdiff_plain;h=8d75ae87846b9ac54741648ed90ede4f220edf2a;p=demos%2Fkafka%2Ftraining

DLT für den auf Message-Conversion basierenden `@KafkaHandler`-Consumer konfiguriert
---

diff --git a/README.sh b/README.sh
index bdeb8b2..c8d1531 100755
--- a/README.sh
+++ b/README.sh
@@ -1,6 +1,6 @@
 #!/bin/bash
 
-IMAGE=juplo/spring-consumer:1.1-messageconverter-SNAPSHOT
+IMAGE=juplo/spring-consumer:1.1-messageconverter-dlt-SNAPSHOT
 
 if [ "$1" = "cleanup" ]
 then
diff --git a/build.gradle b/build.gradle
index 7968723..d8a228f 100644
--- a/build.gradle
+++ b/build.gradle
@@ -8,7 +8,7 @@ plugins {
 }
 
 group = 'de.juplo.kafka'
-version = '1.1-messageconverter-SNAPSHOT'
+version = '1.1-messageconverter-dlt-SNAPSHOT'
 
 java {
 	toolchain {
diff --git a/docker/docker-compose.yml b/docker/docker-compose.yml
index 8c411dd..64976c2 100644
--- a/docker/docker-compose.yml
+++ b/docker/docker-compose.yml
@@ -95,6 +95,7 @@ services:
           echo -n Bereits konfiguriert:
           cat INITIALIZED
           kafka-topics --bootstrap-server kafka:9092 --describe --topic test
+          kafka-topics --bootstrap-server kafka:9092 --describe --topic test-dlt
         else
           kafka-topics --bootstrap-server kafka:9092 \
                        --delete \
@@ -108,6 +109,18 @@ services:
                        --config min.insync.replicas=2 \
           && echo Das Topic \'test\' wurde erfolgreich angelegt: \
           && kafka-topics --bootstrap-server kafka:9092 --describe --topic test \
+          && kafka-topics --bootstrap-server kafka:9092 \
+                       --delete \
+                       --if-exists \
+                       --topic test-dlt
+          kafka-topics --bootstrap-server kafka:9092 \
+                       --create \
+                       --topic test-dlt \
+                       --partitions 2 \
+                       --replication-factor 3 \
+                       --config min.insync.replicas=2 \
+          && echo Das Topic \'test-dlt\' wurde erfolgreich angelegt: \
+          && kafka-topics --bootstrap-server kafka:9092 --describe --topic test-dlt \
           && date > INITIALIZED
         fi
     stop_grace_period: 0s
@@ -143,7 +156,7 @@ services:
       juplo.producer.topic: test
 
   consumer:
-    image: juplo/spring-consumer:1.1-messageconverter-SNAPSHOT
+    image: juplo/spring-consumer:1.1-messageconverter-dlt-SNAPSHOT
     environment:
       spring.kafka.bootstrap-servers: kafka:9092
       spring.kafka.client-id: consumer
@@ -152,7 +165,7 @@ services:
       juplo.consumer.topic: test
 
   peter:
-    image: juplo/spring-consumer:1.1-messageconverter-SNAPSHOT
+    image: juplo/spring-consumer:1.1-messageconverter-dlt-SNAPSHOT
     environment:
       spring.kafka.bootstrap-servers: kafka:9092
       spring.kafka.client-id: peter
@@ -161,7 +174,7 @@ services:
       juplo.consumer.topic: test
 
   ute:
-    image: juplo/spring-consumer:1.1-messageconverter-SNAPSHOT
+    image: juplo/spring-consumer:1.1-messageconverter-dlt-SNAPSHOT
     environment:
       spring.kafka.bootstrap-servers: kafka:9092
       spring.kafka.client-id: ute
diff --git a/pom.xml b/pom.xml
index 2b90634..f06056c 100644
--- a/pom.xml
+++ b/pom.xml
@@ -15,7 +15,7 @@
   <artifactId>spring-consumer</artifactId>
   <name>Spring Consumer</name>
   <description>Super Simple Consumer-Group, that is implemented as Spring-Boot application and configured by Spring Kafka</description>
-  <version>1.1-messageconverter-SNAPSHOT</version>
+  <version>1.1-messageconverter-dlt-SNAPSHOT</version>
 
   <properties>
     <java.version>21</java.version>
diff --git a/src/main/java/de/juplo/kafka/ApplicationConfiguration.java b/src/main/java/de/juplo/kafka/ApplicationConfiguration.java
index 463621a..ba86745 100644
--- a/src/main/java/de/juplo/kafka/ApplicationConfiguration.java
+++ b/src/main/java/de/juplo/kafka/ApplicationConfiguration.java
@@ -3,6 +3,10 @@ package de.juplo.kafka;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.kafka.core.KafkaOperations;
+import org.springframework.kafka.listener.DeadLetterPublishingRecoverer;
+import org.springframework.kafka.listener.DefaultErrorHandler;
+import org.springframework.kafka.listener.SeekUtils;
 import org.springframework.kafka.support.converter.JsonMessageConverter;
 import org.springframework.kafka.support.mapping.DefaultJackson2JavaTypeMapper;
 import org.springframework.kafka.support.mapping.Jackson2JavaTypeMapper;
@@ -34,4 +38,18 @@ public class ApplicationConfiguration
 
     return converter;
   }
+
+  @Bean
+  public DeadLetterPublishingRecoverer deadLetterPublishingRecoverer(KafkaOperations<?, ?> kafkaTemplate)
+  {
+    return new DeadLetterPublishingRecoverer(kafkaTemplate);
+  }
+
+  @Bean
+  public DefaultErrorHandler errorHandler(DeadLetterPublishingRecoverer recoverer)
+  {
+    return new DefaultErrorHandler(
+      recoverer,
+      SeekUtils.DEFAULT_BACK_OFF);
+  }
 }
diff --git a/src/main/resources/application.yml b/src/main/resources/application.yml
index 8ca8a1b..e4897bd 100644
--- a/src/main/resources/application.yml
+++ b/src/main/resources/application.yml
@@ -28,6 +28,8 @@ spring:
     consumer:
       group-id: my-group
       value-deserializer: org.apache.kafka.common.serialization.ByteArrayDeserializer
+    producer:
+      value-serializer: org.apache.kafka.common.serialization.ByteArraySerializer
   level:
     root: INFO
     de.juplo: DEBUG