X-Git-Url: http://juplo.de/gitweb/?a=blobdiff_plain;f=src%2Fmain%2Fjava%2Fde%2Fjuplo%2Fkafka%2FEndlessConsumer.java;h=655151a6680fca4154e69846005e651d638c4a8d;hb=0c9a0c1cf9a0065012743efcd940d8721bc33c20;hp=e4d969748e896ff18863cd465b6e8ab9ee91c2be;hpb=95b1d2d6fd83c68aa0db3e426f173921600e44a6;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 e4d9697..655151a 100644
--- a/src/main/java/de/juplo/kafka/EndlessConsumer.java
+++ b/src/main/java/de/juplo/kafka/EndlessConsumer.java
@@ -1,131 +1,112 @@
 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.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.time.Duration;
-import java.util.Arrays;
-import java.util.Properties;
-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;
 
 
+@RequiredArgsConstructor
 @Slf4j
-public class SimpleConsumer
+@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 recordHandler;
+
   private long consumed = 0;
-  private KafkaConsumer<String, String> consumer;
-  private Lock lock = new ReentrantLock();
-  private Condition stopped = lock.newCondition();
 
 
-  public SimpleConsumer()
+  @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)
   {
-    // tag::create[]
-    Properties props = new Properties();
-    props.put("bootstrap.servers", ":9092");
-    props.put("group.id", "my-consumer"); // << Used for Offset-Commits
-    // end::create[]
-    props.put("auto.offset.reset", "earliest");
-    // tag::create[]
-    props.put("key.deserializer", StringDeserializer.class.getName());
-    props.put("value.deserializer", StringDeserializer.class.getName());
-
-    KafkaConsumer<String, String> consumer = new KafkaConsumer<>(props);
-    // end::create[]
-    this.consumer = consumer;
-  }
+          log.info(
+              "{} - {}: {}/{} - {}={}",
+              id,
+              offset,
+              topic,
+              partition,
+              key,
+              message
+          );
 
+          recordHandler.addNumber(topic, partition, offset, key, message);
 
-  public void run()
-  {
-    String id = "C";
-
-    try
-    {
-      log.info("{} - Subscribing to topic test", id);
-      consumer.subscribe(Arrays.asList("test"));
-
-      // tag::loop[]
-      while (true)
-      {
-        ConsumerRecords<String, String> records =
-            consumer.poll(Duration.ofSeconds(1));
-
-        // Do something with the data...
-        // end::loop[]
-        log.info("{} - Received {} messages", id, records.count());
-        for (ConsumerRecord<String, String> record : records)
-        {
           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,
-              record.offset(),
-              record.topic(),
-              record.partition(),
-              record.key(),
-              record.value()
+              offset,
+              topic,
+              partition,
+              key,
+              message
           );
-        }
-        // tag::loop[]
-      }
-      // end::loop[]
-    }
-    catch(WakeupException e)
-    {
-      log.info("{} - RIIING!", id);
-    }
-    catch(Exception e)
-    {
-      log.error("{} - Unexpected error: {}", id, e.toString());
-    }
-    finally
-    {
-      this.lock.lock();
-      try
-      {
-        log.info("{} - Closing the KafkaConsumer", id);
-        consumer.close();
-        log.info("C - DONE!");
-        stopped.signal();
-      }
-      finally
-      {
-        this.lock.unlock();
-        log.info("{}: Consumed {} messages in total, exiting!", id, consumed);
-      }
-    }
+
+          recordHandler.calculateSum(topic, partition, offset, key, message);
+
+          consumed++;
+  }
+
+  public void start()
+  {
+    if (running())
+      throw new IllegalStateException("Consumer instance " + id + " is already running!");
+
+    log.info("{} - Starting - consumed {} messages before", id, consumed);
+    errorHandler.clearState();
+    registry.getListenerContainer(id).start();
+  }
+
+  public void stop()
+  {
+    if (!running())
+      throw new IllegalStateException("Consumer instance " + id + " is not running!");
+
+    log.info("{} - Stopping", id);
+    registry.getListenerContainer(id).stop();
+    log.info("{} - Stopped - consumed {} messages so far", id, consumed);
   }
 
+  public boolean running()
+  {
+    return registry.getListenerContainer(id).isRunning();
+  }
 
-  public static void main(String[] args) throws Exception
+  public Optional<Exception> exitStatus()
   {
-    SimpleConsumer instance = new SimpleConsumer();
-
-    Runtime.getRuntime().addShutdownHook(new Thread(() ->
-    {
-      instance.lock.lock();
-      try
-      {
-        instance.consumer.wakeup();
-        instance.stopped.await();
-      }
-      catch (InterruptedException e)
-      {
-        log.warn("Interrrupted while waiting for the consumer to stop!", e);
-      }
-      finally
-      {
-        instance.lock.unlock();
-      }
-    }));
-
-    instance.run();
+    if (running())
+      throw new IllegalStateException("No exit-status available: Consumer instance " + id + " is running!");
+
+    return errorHandler.getException();
   }
 }