X-Git-Url: http://juplo.de/gitweb/?a=blobdiff_plain;f=src%2Fmain%2Fjava%2Fde%2Fjuplo%2Fkafka%2FEndlessConsumer.java;h=27c1e446cab68442bdf41ee6bb44baeb5c72e6c5;hb=66ff7d205e66616de8aaca94503dbbcd7d281f6d;hp=63fc10f98e4808f22f9c27f2cab828ef7f41aee9;hpb=384ed293b9d6d71f68031f92bd7bf60670a7ba4b;p=demos%2Fkafka%2Ftraining

diff --git a/src/main/java/de/juplo/kafka/EndlessConsumer.java b/src/main/java/de/juplo/kafka/EndlessConsumer.java
index 63fc10f..27c1e44 100644
--- a/src/main/java/de/juplo/kafka/EndlessConsumer.java
+++ b/src/main/java/de/juplo/kafka/EndlessConsumer.java
@@ -2,211 +2,101 @@ package de.juplo.kafka;
 
 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 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 javax.annotation.PreDestroy;
-import java.time.Duration;
-import java.util.*;
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.locks.Condition;
-import java.util.concurrent.locks.Lock;
-import java.util.concurrent.locks.ReentrantLock;
+import java.util.List;
+import java.util.Optional;
 
 
-@Slf4j
 @RequiredArgsConstructor
-public class EndlessConsumer<K, V> implements Runnable
+@Slf4j
+@KafkaListener(
+    id = "${spring.kafka.client-id}",
+    idIsGroup = false,
+    topics = "${sumup.adder.topic}",
+    autoStartup = "false")
+public class EndlessConsumer
 {
-  private final ExecutorService executor;
   private final String id;
-  private final String topic;
-  private final Consumer<K, V> consumer;
-  private final CommittingConsumerRebalanceListener rebalanceListener;
-  private final RecordHandler<K, V> recordHandler;
-
-  private final Lock lock = new ReentrantLock();
-  private final Condition condition = lock.newCondition();
-  private boolean running = false;
-  private Exception exception;
-  private long consumed = 0;
+  private final KafkaListenerEndpointRegistry registry;
+  private final RecordHandler recordHandler;
 
+  private long consumed = 0;
 
 
-  @Override
-  public void run()
+  @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)
   {
-    try
-    {
-      log.info("{} - Subscribing to topic {}", id, topic);
-      rebalanceListener.enableCommits();
-      consumer.subscribe(Arrays.asList(topic), rebalanceListener);
-
-      while (true)
-      {
-        ConsumerRecords<K, V> records =
-            consumer.poll(Duration.ofSeconds(1));
-
-        // Do something with the data...
-        log.info("{} - Received {} messages", id, records.count());
-        for (ConsumerRecord<K, V> record : records)
-        {
           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++;
-        }
-      }
-    }
-    catch(WakeupException e)
-    {
-      log.info("{} - RIIING! Request to stop consumption.", id);
-      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());
-
-      shutdown(e);
-    }
-    catch(Exception e)
-    {
-      log.error("{} - Unexpected error: {}, disabling commits", id, e.toString(), e);
-      rebalanceListener.disableCommits();
-      shutdown(e);
-    }
-    finally
-    {
-      log.info("{} - Consumer-Thread exiting", id);
-    }
   }
 
-  private void shutdown()
+  @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)
   {
-    shutdown(null);
-  }
+          log.info(
+              "{} - {}: {}/{} - {}={}",
+              id,
+              offset,
+              topic,
+              partition,
+              key,
+              message
+          );
 
-  private void shutdown(Exception e)
-  {
-    lock.lock();
-    try
-    {
-      try
-      {
-        log.info("{} - Unsubscribing from topic {}", id, topic);
-        consumer.unsubscribe();
-      }
-      catch (Exception ue)
-      {
-        log.error(
-            "{} - Error while unsubscribing from topic {}: {}",
-            id,
-            topic,
-            ue.toString());
-      }
-      finally
-      {
-        running = false;
-        exception = e;
-        condition.signal();
-      }
-    }
-    finally
-    {
-      lock.unlock();
-    }
+          recordHandler.calculateSum(topic, partition, offset, key, message);
+
+          consumed++;
   }
 
   public void start()
   {
-    lock.lock();
-    try
-    {
-      if (running)
-        throw new IllegalStateException("Consumer instance " + id + " is already running!");
-
-      log.info("{} - Starting - consumed {} messages before", id, consumed);
-      running = true;
-      exception = null;
-      executor.submit(this);
-    }
-    finally
-    {
-      lock.unlock();
-    }
-  }
+    if (running())
+      throw new IllegalStateException("Consumer instance " + id + " is already running!");
 
-  public synchronized void stop() throws InterruptedException
-  {
-    lock.lock();
-    try
-    {
-      if (!running)
-        throw new IllegalStateException("Consumer instance " + id + " is not running!");
-
-      log.info("{} - Stopping", id);
-      consumer.wakeup();
-      condition.await();
-      log.info("{} - Stopped - consumed {} messages so far", id, consumed);
-    }
-    finally
-    {
-      lock.unlock();
-    }
+    log.info("{} - Starting - consumed {} messages before", id, consumed);
+    registry.getListenerContainer(id).start();
   }
 
-  @PreDestroy
-  public void destroy() throws ExecutionException, InterruptedException
+  public void stop()
   {
-    log.info("{} - Destroy!", id);
-    log.info("{}: Consumed {} messages in total, exiting!", id, consumed);
-  }
+    if (!running())
+      throw new IllegalStateException("Consumer instance " + id + " is not running!");
 
-  public boolean running()
-  {
-    lock.lock();
-    try
-    {
-      return running;
-    }
-    finally
-    {
-      lock.unlock();
-    }
+    log.info("{} - Stopping", id);
+    registry.getListenerContainer(id).stop();
+    log.info("{} - Stopped - consumed {} messages so far", id, consumed);
   }
 
-  public Optional<Exception> exitStatus()
+  public boolean running()
   {
-    lock.lock();
-    try
-    {
-      if (running)
-        throw new IllegalStateException("No exit-status available: Consumer instance " + id + " is running!");
-
-      return Optional.ofNullable(exception);
-    }
-    finally
-    {
-      lock.unlock();
-    }
+    return registry.getListenerContainer(id).isRunning();
   }
 }