juplo.de Git - demos/kafka/training/blob - src/main/java/de/juplo/kafka/SimpleProducer.java

   1 package de.juplo.kafka;
   2
   3 import lombok.extern.slf4j.Slf4j;
   4 import org.apache.kafka.clients.producer.Producer;
   5 import org.apache.kafka.clients.producer.KafkaProducer;
   6 import org.apache.kafka.clients.producer.ProducerRecord;
   7 import org.apache.kafka.common.serialization.StringSerializer;
   8
   9 import java.util.Properties;
  10 import java.util.concurrent.CompletableFuture;
  11
  12
  13 @Slf4j
  14 public class SimpleProducer
  15 {
  16   private final String id;
  17   private final String topic;
  18   private final Producer<String, String> producer;
  19
  20   private long produced = 0;
  21   private volatile boolean running = true;
  22   private volatile boolean done = false;
  23
  24   public SimpleProducer(String broker, String topic, String clientId)
  25   {
  26     Properties props = new Properties();
  27     props.put("bootstrap.servers", broker);
  28     props.put("client.id", clientId); // Nur zur Wiedererkennung
  29     props.put("transactional.id", clientId); // Aktiviert außerdem enable.idempotence=true
  30     props.put("key.serializer", StringSerializer.class.getName());
  31     props.put("value.serializer", StringSerializer.class.getName());
  32
  33     this.id = clientId;
  34     this.topic = topic;
  35     producer = new KafkaProducer<>(props);
  36     producer.initTransactions();
  37   }
  38
  39   public void run()
  40   {
  41     long i = 0;
  42
  43     try
  44     {
  45       for (; running ; i++)
  46       {
  47         send(Long.toString(i%10), Long.toString(i));
  48         Thread.sleep(500);
  49       }
  50     }
  51     catch (InterruptedException e) {}
  52     finally
  53     {
  54       log.info("{}: Closing the KafkaProducer", id);
  55       producer.close();
  56       log.info("{}: Produced {} messages in total, exiting!", id, produced);
  57       done = true;
  58     }
  59   }
  60
  61   void begin()
  62   {
  63     producer.beginTransaction();
  64   }
  65
  66   void commit()
  67   {
  68     producer.commitTransaction();
  69   }
  70
  71   CompletableFuture<Long> send(String key, String value)
  72   {
  73     final CompletableFuture<Long> result = new CompletableFuture<>();
  74     final long time = System.currentTimeMillis();
  75
  76     final ProducerRecord<String, String> record = new ProducerRecord<>(
  77         topic,  // Topic
  78         key,    // Key
  79         value   // Value
  80     );
  81
  82     producer.send(record, (metadata, e) ->
  83     {
  84       long now = System.currentTimeMillis();
  85       if (e == null)
  86       {
  87         // HANDLE SUCCESS
  88         produced++;
  89         log.debug(
  90             "{} - Sent key={} message={} partition={}/{} timestamp={} latency={}ms",
  91             id,
  92             record.key(),
  93             record.value(),
  94             metadata.partition(),
  95             metadata.offset(),
  96             metadata.timestamp(),
  97             now - time
  98         );
  99         result.complete(metadata.offset());
 100       }
 101       else
 102       {
 103         // HANDLE ERROR
 104         log.error(
 105             "{} - ERROR key={} timestamp={} latency={}ms: {}",
 106             id,
 107             record.key(),
 108             metadata == null ? -1 : metadata.timestamp(),
 109             now - time,
 110             e.toString()
 111         );
 112         result.completeExceptionally(e);
 113       }
 114     });
 115
 116     long now = System.currentTimeMillis();
 117     log.trace(
 118         "{} - Queued #{} key={} latency={}ms",
 119         id,
 120         value,
 121         record.key(),
 122         now - time
 123     );
 124
 125     return result;
 126   }
 127
 128
 129   public static void main(String[] args) throws Exception
 130   {
 131     String broker = ":9092";
 132     String topic = "test";
 133     String clientId = "DEV";
 134
 135     switch (args.length)
 136     {
 137       case 3:
 138         clientId = args[2];
 139       case 2:
 140         topic = args[1];
 141       case 1:
 142         broker = args[0];
 143     }
 144
 145     SimpleProducer instance = new SimpleProducer(broker, topic, clientId);
 146
 147     Runtime.getRuntime().addShutdownHook(new Thread(() ->
 148     {
 149       instance.running = false;
 150       while (!instance.done)
 151       {
 152         log.info("Waiting for main-thread...");
 153         try
 154         {
 155           Thread.sleep(1000);
 156         }
 157         catch (InterruptedException e) {}
 158       }
 159       log.info("Shutdown completed.");
 160     }));
 161
 162     log.info(
 163         "Running SimpleProducer: broker={}, topic={}, client-id={}",
 164         broker,
 165         topic,
 166         clientId);
 167     instance.run();
 168   }
 169 }