From 38a548b42bf29cbf01bf0fd7d62add25491747d9 Mon Sep 17 00:00:00 2001
From: Kai Moritz <kai@juplo.de>
Date: Tue, 11 Mar 2025 18:55:21 +0100
Subject: [PATCH] =?utf8?q?Vorlage=20(f=C3=BCr=20das=20Bauen=20des=20Consum?=
 =?utf8?q?ers=20als=20Docker-Image)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

---
 README.sh                                     | 39 ------------
 .../java/de/juplo/kafka/ExampleConsumer.java  | 60 ++++---------------
 2 files changed, 10 insertions(+), 89 deletions(-)
 delete mode 100755 README.sh

diff --git a/README.sh b/README.sh
deleted file mode 100755
index 85b8f960..00000000
--- a/README.sh
+++ /dev/null
@@ -1,39 +0,0 @@
-#!/bin/bash
-
-IMAGE=juplo/simple-consumer:1.0-SNAPSHOT
-
-if [ "$1" = "cleanup" ]
-then
-  docker compose -f docker/docker-compose.yml down -t0 -v --remove-orphans
-  mvn clean
-  exit
-fi
-
-docker compose -f docker/docker-compose.yml up -d --remove-orphans kafka-1 kafka-2 kafka-3
-docker compose -f docker/docker-compose.yml rm -svf consumer
-
-if [[
-  $(docker image ls -q $IMAGE) == "" ||
-  "$1" = "build"
-]]
-then
-  mvn clean install || exit
-else
-  echo "Using image existing images:"
-  docker image ls $IMAGE
-fi
-
-docker compose -f docker/docker-compose.yml up --remove-orphans setup || exit 1
-
-
-docker compose -f docker/docker-compose.yml up -d producer
-docker compose -f docker/docker-compose.yml up -d consumer
-
-sleep 5
-docker compose -f docker/docker-compose.yml stop consumer
-
-docker compose -f docker/docker-compose.yml start consumer
-sleep 5
-
-docker compose -f docker/docker-compose.yml stop producer consumer
-docker compose -f docker/docker-compose.yml logs consumer
diff --git a/src/main/java/de/juplo/kafka/ExampleConsumer.java b/src/main/java/de/juplo/kafka/ExampleConsumer.java
index 891af891..7935d403 100644
--- a/src/main/java/de/juplo/kafka/ExampleConsumer.java
+++ b/src/main/java/de/juplo/kafka/ExampleConsumer.java
@@ -29,70 +29,30 @@ public class ExampleConsumer
     String groupId,
     String clientId)
   {
-    Properties props = new Properties();
-    props.put("bootstrap.servers", broker);
-    props.put("group.id", groupId); // ID für die Offset-Commits
-    props.put("client.id", clientId); // Nur zur Wiedererkennung
-    props.put("key.deserializer", StringDeserializer.class.getName());
-    props.put("value.deserializer", StringDeserializer.class.getName());
+    // TODO:
+    // Instanziierung des KafkaConsumer aus Ihrer bisherigen Implementierung
+    // Hier:
+    // - Instanz in this.consumer ablegen
+    // - Das Attribut broker des Konstruktors für bootstrap.servers verwenden
+    // - Das Attribut groupId des Konstruktors für group.id verwenden
 
     this.id = clientId;
     this.topic = topic;
-    consumer = new KafkaConsumer<>(props);
   }
 
 
   public void run()
   {
-    try
-    {
       log.info("{} - Subscribing to topic {}", id, topic);
-      consumer.subscribe(Arrays.asList(topic));
+      // TODO: Aufruf von consumer.subscribe()
       running = true;
 
       while (true)
       {
-        ConsumerRecords<String, String> records = consumer.poll(Duration.ofSeconds(1));
-
-        log.info("{} - Received {} messages", id, records.count());
-        for (ConsumerRecord<String, String> record : records)
-        {
-          handleRecord(
-            record.topic(),
-            record.partition(),
-            record.offset(),
-            record.key(),
-            record.value());
-        }
+        // TODO: Poll & Consume aus Ihrer bisherigen Implementierung
       }
-    }
-    catch(WakeupException e)
-    {
-      log.info("{} - Consumer was signaled to finish its work", id);
-    }
-    catch(Exception e)
-    {
-      log.error("{} - Unexpected error, unsubscribing!", id, e);
-      consumer.unsubscribe();
-    }
-    finally
-    {
-      running = false;
-      log.info("{} - Closing the KafkaConsumer", id);
-      consumer.close();
-      log.info("{}: Consumed {} messages in total, exiting!", id, consumed);
-    }
-  }
 
-  private void handleRecord(
-    String topic,
-    Integer partition,
-    Long offset,
-    String key,
-    String value)
-  {
-    consumed++;
-    log.info("{} - partition={}-{}, offset={}: {}={}", id, topic, partition, offset, key, value);
+      log.info("{}: Consumed {} messages in total, exiting!", id, consumed);
   }
 
 
@@ -120,7 +80,7 @@ public class ExampleConsumer
 
     Runtime.getRuntime().addShutdownHook(new Thread(() ->
     {
-      instance.consumer.wakeup();
+      // TODO: Endlosschleife beenden
 
       while (instance.running)
       {
-- 
2.20.1