Service ergänzt, der das Dead-Letter-Topic ausliest

[demos/kafka/training] / src / main / java / de / juplo / kafka / EndlessConsumer.java

diff --git a/src/main/java/de/juplo/kafka/EndlessConsumer.java b/src/main/java/de/juplo/kafka/EndlessConsumer.java
index 01397a2..27c1e44 100644 (file)
--- a/src/main/java/de/juplo/kafka/EndlessConsumer.java
+++ b/src/main/java/de/juplo/kafka/EndlessConsumer.java
@@ -3,8 +3,12 @@ package de.juplo.kafka;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.kafka.clients.consumer.ConsumerRecord;
+import org.springframework.kafka.annotation.KafkaHandler;
 import org.springframework.kafka.annotation.KafkaListener;
 import org.springframework.kafka.config.KafkaListenerEndpointRegistry;
+import org.springframework.kafka.support.KafkaHeaders;
+import org.springframework.messaging.handler.annotation.Header;
+import org.springframework.messaging.handler.annotation.Payload;
 
 import java.util.List;
 import java.util.Optional;
@@ -12,34 +16,62 @@ import java.util.Optional;
 
 @RequiredArgsConstructor
 @Slf4j
-public class EndlessConsumer<K, V>
+@KafkaListener(
+    id = "${spring.kafka.client-id}",
+    idIsGroup = false,
+    topics = "${sumup.adder.topic}",
+    autoStartup = "false")
+public class EndlessConsumer
 {
   private final String id;
   private final KafkaListenerEndpointRegistry registry;
-  private final ApplicationErrorHandler errorHandler;
-  private final RecordHandler<K, V> recordHandler;
+  private final RecordHandler recordHandler;
 
   private long consumed = 0;
 
 
-  @KafkaListener(
-      id = "${spring.kafka.client-id}",
-      idIsGroup = false,
-      topics = "${sumup.adder.topic}",
-      autoStartup = "false")
-  public void accept(ConsumerRecord<K, V> record)
+  @KafkaHandler
+  public void addNumber(
+    @Header(KafkaHeaders.RECEIVED_MESSAGE_KEY) String key,
+    @Header(KafkaHeaders.RECEIVED_TOPIC) String topic,
+    @Header(KafkaHeaders.RECEIVED_PARTITION_ID) Integer partition,
+    @Header(KafkaHeaders.OFFSET) Long offset,
+    @Payload MessageAddNumber message)
   {
           log.info(
               "{} - {}: {}/{} - {}={}",
               id,
-              record.offset(),
-              record.topic(),
-              record.partition(),
-              record.key(),
-              record.value()
+              offset,
+              topic,
+              partition,
+              key,
+              message
           );
 
-          recordHandler.accept(record);
+          recordHandler.addNumber(topic, partition, offset, key, message);
+
+          consumed++;
+  }
+
+  @KafkaHandler
+  public void calculateSum(
+    @Header(KafkaHeaders.RECEIVED_MESSAGE_KEY) String key,
+    @Header(KafkaHeaders.RECEIVED_TOPIC) String topic,
+    @Header(KafkaHeaders.RECEIVED_PARTITION_ID) Integer partition,
+    @Header(KafkaHeaders.OFFSET) Long offset,
+    @Payload MessageCalculateSum message)
+  {
+          log.info(
+              "{} - {}: {}/{} - {}={}",
+              id,
+              offset,
+              topic,
+              partition,
+              key,
+              message
+          );
+
+          recordHandler.calculateSum(topic, partition, offset, key, message);
 
           consumed++;
   }
@@ -50,7 +82,6 @@ public class EndlessConsumer<K, V>
       throw new IllegalStateException("Consumer instance " + id + " is already running!");
 
     log.info("{} - Starting - consumed {} messages before", id, consumed);
-    errorHandler.clearState();
     registry.getListenerContainer(id).start();
   }
 
@@ -68,12 +99,4 @@ public class EndlessConsumer<K, V>
   {
     return registry.getListenerContainer(id).isRunning();
   }
-
-  public Optional<Exception> exitStatus()
-  {
-    if (running())
-      throw new IllegalStateException("No exit-status available: Consumer instance " + id + " is running!");
-
-    return errorHandler.getException();
-  }
 }