Möglichst einfacher Producer auf Basis des KafkaTemplate

[demos/kafka/training] / src / main / java / de / juplo / kafka / Application.java

diff --git a/src/main/java/de/juplo/kafka/Application.java b/src/main/java/de/juplo/kafka/Application.java
index 9fcaa6e..dda9b11 100644 (file)
--- a/src/main/java/de/juplo/kafka/Application.java
+++ b/src/main/java/de/juplo/kafka/Application.java
@@ -1,151 +1,88 @@
 package de.juplo.kafka;
 
 import lombok.extern.slf4j.Slf4j;
-import org.apache.kafka.clients.producer.KafkaProducer;
-import org.apache.kafka.clients.producer.ProducerRecord;
-import org.apache.kafka.common.serialization.StringSerializer;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.ApplicationArguments;
+import org.springframework.boot.ApplicationRunner;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.kafka.core.KafkaTemplate;
+import org.springframework.kafka.support.SendResult;
+import org.springframework.util.concurrent.ListenableFuture;
 
-import java.util.Properties;
+import java.util.List;
 
 
 @Slf4j
-public class SimpleProducer
+@SpringBootApplication
+public class Application implements ApplicationRunner
 {
-  private final String id;
-  private final String topic;
-  private final KafkaProducer<String, String> producer;
+  public final static String ARG_NUM = "num";
 
-  private long produced = 0;
-  private volatile boolean running = true;
-  private volatile boolean done = false;
+  @Autowired
+  KafkaTemplate<String, String> kafkaTemplate;
 
-  public SimpleProducer(String broker, String topic, String clientId)
-  {
-    Properties props = new Properties();
-    props.put("bootstrap.servers", broker);
-    props.put("client.id", clientId); // Nur zur Wiedererkennung
-    props.put("key.serializer", StringSerializer.class.getName());
-    props.put("value.serializer", StringSerializer.class.getName());
-
-    producer = new KafkaProducer<>(props);
 
-    this.topic = topic;
-    this.id = clientId;
+  void send(String key, String value)
+  {
+    ListenableFuture<SendResult<String, String>> listenableFuture =
+        kafkaTemplate.sendDefault(key, value);
+
+    listenableFuture.addCallback(
+        result -> log.debug(
+            "Sent {}={} to partition={}, offset={}",
+            result.getProducerRecord().key(),
+            result.getProducerRecord().value(),
+            result.getRecordMetadata().partition(),
+            result.getRecordMetadata().offset()),
+        e -> log.error("ERROR sendig message", e));
   }
 
-  public void run()
+  @Override
+  public void run(ApplicationArguments args)
   {
-    long i = 0;
+    int num = 10;
 
-    try
+    if (args.containsOption(ARG_NUM))
     {
-      for (; running ; i++)
+      List<String> numArgs = args.getOptionValues(ARG_NUM);
+      if (numArgs.size() > 1)
       {
-        send(Long.toString(i%10), Long.toString(i));
-        Thread.sleep(500);
+        log.error(
+            "Only one occurence of argument {} is allowed, but found: {}",
+            ARG_NUM,
+            numArgs.size());
+        return;
       }
-    }
-    catch (InterruptedException e) {}
-    finally
-    {
-      log.info("{}: Closing the KafkaProducer", id);
-      producer.close();
-      log.info("{}: Produced {} messages in total, exiting!", id, produced);
-      done = true;
-    }
-  }
-
-  void send(String key, String value)
-  {
-    final long time = System.currentTimeMillis();
-
-    final ProducerRecord<String, String> record = new ProducerRecord<>(
-        topic,  // Topic
-        key,    // Key
-        value   // Value
-    );
 
-    producer.send(record, (metadata, e) ->
-    {
-      long now = System.currentTimeMillis();
-      if (e == null)
+      try
       {
-        // HANDLE SUCCESS
-        produced++;
-        log.debug(
-            "{} - Sent key={} message={} partition={}/{} timestamp={} latency={}ms",
-            id,
-            record.key(),
-            record.value(),
-            metadata.partition(),
-            metadata.offset(),
-            metadata.timestamp(),
-            now - time
-        );
+        num = Integer.parseInt(numArgs.get(0));
       }
-      else
+      catch (NumberFormatException e)
       {
-        // HANDLE ERROR
-        log.error(
-            "{} - ERROR key={} timestamp={} latency={}ms: {}",
-            id,
-            record.key(),
-            metadata == null ? -1 : metadata.timestamp(),
-            now - time,
-            e.toString()
-        );
+        log.error("{} is not a number: {}", numArgs.get(0), e.getMessage());
       }
-    });
-
-    long now = System.currentTimeMillis();
-    log.trace(
-        "{} - Queued #{} key={} latency={}ms",
-        id,
-        value,
-        record.key(),
-        now - time
-    );
-  }
-
-
-  public static void main(String[] args) throws Exception
-  {
-    String broker = ":9092";
-    String topic = "test";
-    String clientId = "DEV";
-
-    switch (args.length)
-    {
-      case 3:
-        clientId = args[2];
-      case 2:
-        topic = args[1];
-      case 1:
-        broker = args[0];
     }
 
-    SimpleProducer instance = new SimpleProducer(broker, topic, clientId);
-
-    Runtime.getRuntime().addShutdownHook(new Thread(() ->
+    for (int i = 0; i < num; i++)
     {
-      instance.running = false;
-      while (!instance.done)
+      send(Long.toString(i%10), Long.toString(i));
+      try
       {
-        log.info("Waiting for main-thread...");
-        try
-        {
-          Thread.sleep(1000);
-        }
-        catch (InterruptedException e) {}
+        Thread.sleep(500);
+      }
+      catch (InterruptedException e)
+      {
+        log.info("Interrupted after sending {} messages", i);
+        return;
       }
-      log.info("Shutdown completed.");
-    }));
+    }
+  }
+
 
-    log.info(
-        "Running SimpleProducer: broker={}, topic={}, client-id={}",
-        broker,
-        topic,
-        clientId);
-    instance.run();
+  public static void main(String[] args)
+  {
+    SpringApplication.run(Application.class, args);
   }
 }