Refactor: `EndlessConsumer` ist selbst ein `ConsumerRebalanceListener`

[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 0a95b2c..8802df9 100644 (file)
--- a/src/main/java/de/juplo/kafka/EndlessConsumer.java
+++ b/src/main/java/de/juplo/kafka/EndlessConsumer.java
@@ -4,6 +4,7 @@ import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.kafka.clients.consumer.*;
 import org.apache.kafka.common.TopicPartition;
+import org.apache.kafka.common.errors.RecordDeserializationException;
 import org.apache.kafka.common.errors.WakeupException;
 
 import javax.annotation.PreDestroy;
@@ -18,7 +19,7 @@ import java.util.concurrent.locks.ReentrantLock;
 
 @Slf4j
 @RequiredArgsConstructor
-public class EndlessConsumer<K, V> implements Runnable
+public class EndlessConsumer<K, V> implements ConsumerRebalanceListener, Runnable
 {
   private final ExecutorService executor;
   private final String id;
@@ -36,55 +37,55 @@ public class EndlessConsumer<K, V> implements Runnable
   private final Map<Integer, Long> offsets = new HashMap<>();
 
 
+  @Override
+  public void onPartitionsRevoked(Collection<TopicPartition> partitions)
+  {
+    partitions.forEach(tp ->
+    {
+      Integer partition = tp.partition();
+      Long newOffset = consumer.position(tp);
+      Long oldOffset = offsets.remove(partition);
+      log.info(
+          "{} - removing partition: {}, consumed {} records (offset {} -> {})",
+          id,
+          partition,
+          newOffset - oldOffset,
+          oldOffset,
+          newOffset);
+      Map<String, Long> removed = seen.remove(partition);
+      for (String key : removed.keySet())
+      {
+        log.info(
+            "{} - Seen {} messages for partition={}|key={}",
+            id,
+            removed.get(key),
+            partition,
+            key);
+      }
+    });
+  }
+
+  @Override
+  public void onPartitionsAssigned(Collection<TopicPartition> partitions)
+  {
+    partitions.forEach(tp ->
+    {
+      Integer partition = tp.partition();
+      Long offset = consumer.position(tp);
+      log.info("{} - adding partition: {}, offset={}", id, partition, offset);
+      offsets.put(partition, offset);
+      seen.put(partition, new HashMap<>());
+    });
+  }
+
+
   @Override
   public void run()
   {
     try
     {
       log.info("{} - Subscribing to topic {}", id, topic);
-      consumer.subscribe(Arrays.asList(topic), new ConsumerRebalanceListener()
-      {
-        @Override
-        public void onPartitionsRevoked(Collection<TopicPartition> partitions)
-        {
-          partitions.forEach(tp ->
-          {
-            Integer partition = tp.partition();
-            Long newOffset = consumer.position(tp);
-            Long oldOffset = offsets.remove(partition);
-            log.info(
-                "{} - removing partition: {}, consumed {} records (offset {} -> {})",
-                id,
-                partition,
-                newOffset - oldOffset,
-                oldOffset,
-                newOffset);
-            Map<String, Long> removed = seen.remove(partition);
-            for (String key : removed.keySet())
-            {
-              log.info(
-                  "{} - Seen {} messages for partition={}|key={}",
-                  id,
-                  removed.get(key),
-                  partition,
-                  key);
-            }
-          });
-        }
-
-        @Override
-        public void onPartitionsAssigned(Collection<TopicPartition> partitions)
-        {
-          partitions.forEach(tp ->
-          {
-            Integer partition = tp.partition();
-            Long offset = consumer.position(tp);
-            log.info("{} - adding partition: {}, offset={}", id, partition, offset);
-            offsets.put(partition, offset);
-            seen.put(partition, new HashMap<>());
-          });
-        }
-      });
+      consumer.subscribe(Arrays.asList(topic), this);
 
       while (true)
       {
@@ -128,6 +129,20 @@ public class EndlessConsumer<K, V> implements Runnable
       consumer.commitSync();
       shutdown();
     }
+    catch(RecordDeserializationException e)
+    {
+      TopicPartition tp = e.topicPartition();
+      long offset = e.offset();
+      log.error(
+          "{} - Could not deserialize  message on topic {} with offset={}: {}",
+          id,
+          tp,
+          offset,
+          e.getCause().toString());
+
+      consumer.commitSync();
+      shutdown(e);
+    }
     catch(Exception e)
     {
       log.error("{} - Unexpected error: {}", id, e.toString(), e);