Versand über das `KafkaTemplate` mit dem `MessageCovnerter`

* Verwendung des `ByteArraySerializer`
* Type-Mappings für den `StringJsonMessageConverter` konfiguriert

diff --git a/README.sh b/README.sh
index 982f7bd..c208c12 100755 (executable)
--- a/README.sh
+++ b/README.sh
@@ -1,6 +1,6 @@
 #!/bin/bash
 
-IMAGE=juplo/spring-producer:1.0-json-SNAPSHOT
+IMAGE=juplo/spring-producer:1.0-messageconverter-SNAPSHOT
 
 if [ "$1" = "cleanup" ]
 then

diff --git a/build.gradle b/build.gradle
index 7556511..2d30d50 100644 (file)
--- a/build.gradle
+++ b/build.gradle
@@ -8,7 +8,7 @@ plugins {
 }
 
 group = 'de.juplo.kafka'
-version = '1.0-json-SNAPSHOT'
+version = '1.0-messageconverter-SNAPSHOT'
 
 java {
        toolchain {
@@ -27,10 +27,10 @@ repositories {
 }
 
 dependencies {
+       implementation 'org.springframework.kafka:spring-kafka'
        implementation 'org.springframework.boot:spring-boot-starter-actuator'
        implementation 'org.springframework.boot:spring-boot-starter-validation'
        implementation 'org.springframework.boot:spring-boot-starter-web'
-       implementation 'org.springframework.kafka:spring-kafka'
        compileOnly 'org.projectlombok:lombok'
        developmentOnly 'org.springframework.boot:spring-boot-devtools'
        annotationProcessor 'org.springframework.boot:spring-boot-configuration-processor'

diff --git a/docker/docker-compose.yml b/docker/docker-compose.yml
index ac00f3c..fe5faf2 100644 (file)
--- a/docker/docker-compose.yml
+++ b/docker/docker-compose.yml
@@ -136,7 +136,7 @@ services:
       - kafka-3
 
   producer:
-    image: juplo/spring-producer:1.0-json-SNAPSHOT
+    image: juplo/spring-producer:1.0-messageconverter-SNAPSHOT
     environment:
       spring.kafka.bootstrap-servers: kafka:9092
       spring.kafka.client-id: producer

diff --git a/pom.xml b/pom.xml
index 7bcb24c..9c93492 100644 (file)
--- a/pom.xml
+++ b/pom.xml
@@ -14,8 +14,8 @@
   <groupId>de.juplo.kafka</groupId>
   <artifactId>spring-producer</artifactId>
   <name>Spring Producer</name>
-  <description>A Simple Producer, based on Spring Boot, that sends messages via Kafka</description>
-  <version>1.0-json-SNAPSHOT</version>
+  <description>A Simple Producer, based on the KafkaTemplate and Spring Boot, that sends messages via Kafka</description>
+  <version>1.0-messageconverter-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 e212a25..57fa246 100644 (file)
--- a/src/main/java/de/juplo/kafka/ApplicationConfiguration.java
+++ b/src/main/java/de/juplo/kafka/ApplicationConfiguration.java
@@ -1,14 +1,22 @@
 package de.juplo.kafka;
 
-import org.apache.kafka.clients.producer.Producer;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import org.springframework.beans.factory.annotation.Value;
+import org.springframework.boot.autoconfigure.kafka.KafkaProperties;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.kafka.core.KafkaTemplate;
 import org.springframework.kafka.core.ProducerFactory;
+import org.springframework.kafka.support.converter.ByteArrayJsonMessageConverter;
+import org.springframework.kafka.support.converter.JsonMessageConverter;
+import org.springframework.kafka.support.mapping.DefaultJackson2JavaTypeMapper;
+import org.springframework.kafka.support.mapping.Jackson2JavaTypeMapper;
 
 import java.time.Duration;
+import java.util.HashMap;
+import java.util.Map;
 
 
 @Configuration
@@ -19,7 +27,8 @@ public class ApplicationConfiguration
   public ExampleProducer exampleProducer(
     @Value("${spring.kafka.client-id}") String clientId,
     ApplicationProperties properties,
-    Producer<String, SumupMessage> kafkaProducer,
+    KafkaProperties kafkaProperties,
+    KafkaTemplate<String, SumupMessage> kafkaTemplate,
     ConfigurableApplicationContext applicationContext)
   {
     return
@@ -29,13 +38,37 @@ public class ApplicationConfiguration
         properties.getProducerProperties().getThrottle() == null
           ? Duration.ofMillis(500)
           : properties.getProducerProperties().getThrottle(),
-        kafkaProducer,
+        kafkaTemplate,
         () -> applicationContext.close());
+
+  }
+
+  @Bean
+  public KafkaTemplate<String, SumupMessage> kafkaTemplate(
+    ProducerFactory<String, SumupMessage> producerFactory,
+    JsonMessageConverter jsonMessageConverter) {
+
+    KafkaTemplate<String, SumupMessage> template = new KafkaTemplate<>(producerFactory);
+    template.setMessageConverter(jsonMessageConverter);
+
+    return template;
   }
 
-  @Bean(destroyMethod = "")
-  public Producer<?, ?> kafkaProducer(ProducerFactory<?, ?> producerFactory)
+  @Bean
+  public ByteArrayJsonMessageConverter jsonMessageConverter(ObjectMapper objectMapper)
   {
-    return producerFactory.createProducer();
+    ByteArrayJsonMessageConverter converter = new ByteArrayJsonMessageConverter();
+    DefaultJackson2JavaTypeMapper typeMapper = new DefaultJackson2JavaTypeMapper();
+
+    // Verwende eine einfache, kurze Type-ID anstatt FQN
+    typeMapper.setTypePrecedence(Jackson2JavaTypeMapper.TypePrecedence.TYPE_ID);
+    Map<String, Class<?>> typeMappings = new HashMap<>();
+    typeMappings.put("ADD", AddNumberMessage.class);
+    typeMappings.put("CALC", CalculateSumMessage.class);
+    typeMapper.setIdClassMapping(typeMappings);
+
+    converter.setTypeMapper(typeMapper);
+
+    return converter;
   }
 }

diff --git a/src/main/java/de/juplo/kafka/ExampleProducer.java b/src/main/java/de/juplo/kafka/ExampleProducer.java
index 0d152f7..9a262b1 100644 (file)
--- a/src/main/java/de/juplo/kafka/ExampleProducer.java
+++ b/src/main/java/de/juplo/kafka/ExampleProducer.java
@@ -1,8 +1,11 @@
 package de.juplo.kafka;
 
 import lombok.extern.slf4j.Slf4j;
-import org.apache.kafka.clients.producer.Producer;
-import org.apache.kafka.clients.producer.ProducerRecord;
+import org.apache.kafka.clients.producer.RecordMetadata;
+import org.springframework.kafka.core.KafkaTemplate;
+import org.springframework.kafka.support.KafkaHeaders;
+import org.springframework.messaging.Message;
+import org.springframework.messaging.support.MessageBuilder;
 
 import java.time.Duration;
 
@@ -13,7 +16,7 @@ public class ExampleProducer implements Runnable
   private final String id;
   private final String topic;
   private final Duration throttle;
-  private final Producer<String, SumupMessage> producer;
+  private final KafkaTemplate<String, SumupMessage> kafkaTemplate;
   private final Thread workerThread;
   private final Runnable closeCallback;
 
@@ -25,13 +28,13 @@ public class ExampleProducer implements Runnable
     String id,
     String topic,
     Duration throttle,
-    Producer<String, SumupMessage> producer,
+    KafkaTemplate<String, SumupMessage> kafkaTemplate,
     Runnable closeCallback)
   {
     this.id = id;
     this.topic = topic;
     this.throttle = throttle;
-    this.producer = producer;
+    this.kafkaTemplate = kafkaTemplate;
 
     workerThread = new Thread(this, "ExampleProducer Worker-Thread");
     workerThread.start();
@@ -77,8 +80,6 @@ public class ExampleProducer implements Runnable
     }
     finally
     {
-      log.info("{}: Closing the KafkaProducer", id);
-      producer.close();
       log.info("{}: Produced {} messages in total, exiting!", id, produced);
     }
   }
@@ -87,18 +88,18 @@ public class ExampleProducer implements Runnable
   {
     final long time = System.currentTimeMillis();
 
-    final ProducerRecord<String, SumupMessage> record = new ProducerRecord<>(
-      topic,  // Topic
-      key,    // Key
-      value   // Value
-    );
+    Message<SumupMessage> message = MessageBuilder
+      .withPayload(value)
+      .setHeader(KafkaHeaders.TOPIC, topic)
+      .build();
 
-    producer.send(record, (metadata, e) ->
+    kafkaTemplate.send(message).whenComplete((result, e) ->
     {
       long now = System.currentTimeMillis();
       if (e == null)
       {
         // HANDLE SUCCESS
+        RecordMetadata metadata = result.getRecordMetadata();
         log.debug(
           "{} - Sent message {}={}, partition={}, offset={}, timestamp={}, latency={}ms",
           id,

diff --git a/src/main/resources/application.yml b/src/main/resources/application.yml
index daf440e..5c71180 100644 (file)
--- a/src/main/resources/application.yml
+++ b/src/main/resources/application.yml
@@ -11,11 +11,8 @@ spring:
       buffer-memory: 33554432
       batch-size: 16384
       compression-type: gzip
-      value-serializer: org.springframework.kafka.support.serializer.JsonSerializer
+      value-serializer: org.apache.kafka.common.serialization.ByteArraySerializer
       properties:
-        spring.json.type.mapping: >-
-          ADD:de.juplo.kafka.AddNumberMessage,
-          CALC:de.juplo.kafka.CalculateSumMessage
         delivery-timeout: 10s
         max-block: 5s
         linger: 0
@@ -34,17 +31,8 @@ management:
       enabled: true
 info:
   kafka:
-    bootstrap-server: ${juplo.bootstrap-server}
-    client-id: ${juplo.client-id}
     producer:
       topic: ${juplo.producer.topic}
-      acks: ${juplo.producer.acks}
-      delivery-timeout: ${juplo.producer.delivery-timeout}
-      max-block: ${juplo.producer.max-block}
-      buffer-memory: ${juplo.producer.buffer-memory}
-      batch-size: ${juplo.producer.batch-size}
-      linger: ${juplo.producer.linger}
-      compression-type: ${juplo.producer.compression-type}
       throttle: ${juplo.producer.throttle}
 logging:
   level:

diff --git a/src/test/java/de/juplo/kafka/ApplicationTests.java b/src/test/java/de/juplo/kafka/ApplicationTests.java
index 3a4493e..7687e9c 100644 (file)
--- a/src/test/java/de/juplo/kafka/ApplicationTests.java
+++ b/src/test/java/de/juplo/kafka/ApplicationTests.java
@@ -27,7 +27,6 @@ import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.
 
 @SpringBootTest(
   properties = {
-    "spring.kafka.bootstrap-servers=${spring.embedded.kafka.brokers}",
     "spring.kafka.consumer.auto-offset-reset=earliest",
     "juplo.producer.topic=" + TOPIC})
 @AutoConfigureMockMvc