X-Git-Url: http://juplo.de/gitweb/?a=blobdiff_plain;f=src%2Fmain%2Fjava%2Fde%2Fjuplo%2Fkafka%2FEndlessConsumer.java;h=04a0a3af8e112e55f7c34a60fe785713c27283b8;hb=1709f0e4f41be7e3b955d19769697a517633827d;hp=22dce95ee17a7c6c9f089bbe5e9377fe8bdcdba3;hpb=e87f4bb2bc188252955fb4932ddd99161ba621d3;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 22dce95..04a0a3a 100644
--- a/src/main/java/de/juplo/kafka/EndlessConsumer.java
+++ b/src/main/java/de/juplo/kafka/EndlessConsumer.java
@@ -1,145 +1,130 @@
 package de.juplo.kafka;
 
+import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.kafka.clients.consumer.ConsumerRecord;
-import org.apache.kafka.clients.consumer.ConsumerRecords;
-import org.apache.kafka.clients.consumer.KafkaConsumer;
-import org.apache.kafka.common.errors.WakeupException;
-import org.apache.kafka.common.serialization.StringDeserializer;
+import org.apache.kafka.common.TopicPartition;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.kafka.annotation.KafkaListener;
+import org.springframework.kafka.config.KafkaListenerEndpointRegistry;
+import org.springframework.kafka.listener.ConsumerAwareRebalanceListener;
+import org.springframework.stereotype.Component;
 
-import javax.annotation.PreDestroy;
-import java.time.Duration;
-import java.util.Arrays;
-import java.util.Properties;
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Future;
-import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.function.Consumer;
 
 
+@Component
 @Slf4j
-public class EndlessConsumer implements Runnable
+@RequiredArgsConstructor
+public class EndlessConsumer<K, V> implements ConsumerAwareRebalanceListener
 {
-  private final ExecutorService executor;
-  private final String bootstrapServer;
-  private final String groupId;
-  private final String id;
-  private final String topic;
+  @Autowired
+  private KafkaListenerEndpointRegistry registry;
+  @Value("${spring.kafka.consumer.client-id}")
+  String id;
+  @Autowired
+  Consumer<ConsumerRecord<K, V>> handler;
 
-  private AtomicBoolean running = new AtomicBoolean();
   private long consumed = 0;
-  private KafkaConsumer<String, String> consumer = null;
-  private Future<?> future = null;
-
-  public EndlessConsumer(
-      ExecutorService executor,
-      String bootstrapServer,
-      String groupId,
-      String clientId,
-      String topic)
-  {
-    this.executor = executor;
-    this.bootstrapServer = bootstrapServer;
-    this.groupId = groupId;
-    this.id = clientId;
-    this.topic = topic;
-  }
 
-  @Override
-  public void run()
-  {
-    Properties props = new Properties();
-    props.put("bootstrap.servers", bootstrapServer);
-    props.put("group.id", groupId);
-    props.put("client.id", id);
-    props.put("auto.offset.reset", "earliest");
-    props.put("key.deserializer", StringDeserializer.class.getName());
-    props.put("value.deserializer", StringDeserializer.class.getName());
+  private final Map<Integer, Map<String, Long>> seen = new HashMap<>();
+  private final Map<Integer, Long> offsets = new HashMap<>();
 
-    this.consumer = new KafkaConsumer<>(props);
 
-    try
+  @Override
+  public void onPartitionsRevokedBeforeCommit(
+      org.apache.kafka.clients.consumer.Consumer<?, ?> consumer,
+      Collection<TopicPartition> partitions)
+  {
+    partitions.forEach(tp ->
     {
-      log.info("{} - Subscribing to topic {}", id, topic);
-      consumer.subscribe(Arrays.asList(topic));
-
-      while (true)
+      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())
       {
-        ConsumerRecords<String, String> records =
-            consumer.poll(Duration.ofSeconds(1));
-
-        // Do something with the data...
-        log.info("{} - Received {} messages", id, records.count());
-        for (ConsumerRecord<String, String> record : records)
-        {
-          consumed++;
-          log.info(
-              "{} - {}: {}/{} - {}={}",
-              id,
-              record.offset(),
-              record.topic(),
-              record.partition(),
-              record.key(),
-              record.value()
-          );
-        }
+        log.info(
+            "{} - Seen {} messages for partition={}|key={}",
+            id,
+            removed.get(key),
+            partition,
+            key);
       }
-    }
-    catch(WakeupException e)
-    {
-      log.info("{} - RIIING!", id);
-    }
-    catch(Exception e)
-    {
-      log.error("{} - Unexpected error: {}", id, e.toString());
-      running.set(false); // Mark the instance as not running
-    }
-    finally
+    });
+  }
+
+  @Override
+  public void onPartitionsAssigned(
+      org.apache.kafka.clients.consumer.Consumer<?, ?> consumer,
+      Collection<TopicPartition> partitions)
+  {
+    partitions.forEach(tp ->
     {
-      log.info("{} - Closing the KafkaConsumer", id);
-      consumer.close();
-      log.info("{} - Consumer-Thread exiting", id);
-    }
+      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<>());
+    });
+  }
+
+
+  @KafkaListener(
+      id = "${spring.kafka.consumer.client-id}",
+      idIsGroup = false,
+      topics = "${consumer.topic}",
+      autoStartup = "false")
+  public void receive(ConsumerRecord<K, V> record)
+  {
+    log.info(
+        "{} - {}: {}/{} - {}={}",
+        id,
+        record.offset(),
+        record.topic(),
+        record.partition(),
+        record.key(),
+        record.value()
+    );
+
+    handler.accept(record);
+
+    consumed++;
   }
 
 
   public synchronized void start()
   {
-    boolean stateChanged = running.compareAndSet(false, true);
-    if (!stateChanged)
-      throw new RuntimeException("Consumer instance " + id + " is already running!");
+    if (registry.getListenerContainer(id).isChildRunning())
+      throw new IllegalStateException("Consumer instance " + id + " is already running!");
 
     log.info("{} - Starting - consumed {} messages before", id, consumed);
-    future = executor.submit(this);
+    registry.getListenerContainer(id).start();
   }
 
-  public synchronized void stop() throws ExecutionException, InterruptedException
+  public synchronized void stop()
   {
-    boolean stateChanged = running.compareAndSet(true, false);
-    if (!stateChanged)
-      throw new RuntimeException("Consumer instance " + id + " is not running!");
+    if (!registry.getListenerContainer(id).isChildRunning())
+      throw new IllegalStateException("Consumer instance " + id + " is not running!");
 
     log.info("{} - Stopping", id);
-    consumer.wakeup();
-    future.get();
+    registry.getListenerContainer(id).stop();
     log.info("{} - Stopped - consumed {} messages so far", id, consumed);
   }
 
-  @PreDestroy
-  public void destroy() throws ExecutionException, InterruptedException
+  public synchronized boolean isRunning()
   {
-    log.info("{} - Destroy!", id);
-    try
-    {
-      stop();
-    }
-    catch (IllegalStateException e)
-    {
-      log.info("{} - Was already stopped", id);
-    }
-    finally
-    {
-      log.info("{}: Consumed {} messages in total, exiting!", id, consumed);
-    }
+    return registry.getListenerContainer(id).isChildRunning();
   }
 }