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

   1 package de.juplo.kafka;
   2
   3 import lombok.extern.slf4j.Slf4j;
   4 import org.apache.kafka.clients.producer.KafkaProducer;
   5 import org.apache.kafka.clients.producer.ProducerRecord;
   6 import org.apache.kafka.common.serialization.StringSerializer;
   7 import org.springframework.web.bind.annotation.*;
   8 import org.springframework.web.context.request.async.DeferredResult;
   9
  10 import javax.annotation.PreDestroy;
  11 import java.math.BigInteger;
  12 import java.util.Properties;
  13 import java.util.concurrent.ExecutionException;
  14
  15
  16 @Slf4j
  17 @RestController
  18 public class RestProducer
  19 {
  20   private final String id;
  21   private final String topic;
  22   private final Integer partition;
  23   private final KafkaProducer<String, String> producer;
  24
  25   private long produced = 0;
  26
  27   public RestProducer(ApplicationProperties properties)
  28   {
  29     this.id = properties.getClientId();
  30     this.topic = properties.getTopic();
  31     this.partition = properties.getPartition();
  32
  33     Properties props = new Properties();
  34     props.put("bootstrap.servers", properties.getBootstrapServer());
  35     props.put("client.id", properties.getClientId());
  36     props.put("acks", properties.getAcks());
  37     props.put("batch.size", properties.getBatchSize());
  38     props.put("delivery.timeout.ms", 20000); // 20 Sekunden
  39     props.put("request.timeout.ms",  10000); // 10 Sekunden
  40     props.put("linger.ms", properties.getLingerMs());
  41     props.put("compression.type", properties.getCompressionType());
  42     props.put("key.serializer", StringSerializer.class.getName());
  43     props.put("value.serializer", StringSerializer.class.getName());
  44
  45     this.producer = new KafkaProducer<>(props);
  46   }
  47
  48   @PostMapping(path = "{key}")
  49   public DeferredResult<ProduceResult> send(
  50       @PathVariable String key,
  51       @RequestHeader(name = "X-id", required = false) Long correlationId,
  52       @RequestBody String value)
  53   {
  54     DeferredResult<ProduceResult> result = new DeferredResult<>();
  55
  56     final long time = System.currentTimeMillis();
  57
  58     final ProducerRecord<String, String> record = new ProducerRecord<>(
  59         topic,  // Topic
  60         partition, // Partition
  61         key,    // Key
  62         value   // Value
  63     );
  64
  65     record.headers().add("source", id.getBytes());
  66     if (correlationId != null)
  67     {
  68       record.headers().add("id", BigInteger.valueOf(correlationId).toByteArray());
  69     }
  70
  71     producer.send(record, (metadata, e) ->
  72     {
  73       long now = System.currentTimeMillis();
  74       if (e == null)
  75       {
  76         // HANDLE SUCCESS
  77         produced++;
  78         result.setResult(new ProduceSuccess(metadata.partition(), metadata.offset()));
  79         log.debug(
  80             "{} - Sent key={} message={} partition={}/{} timestamp={} latency={}ms",
  81             id,
  82             record.key(),
  83             record.value(),
  84             metadata.partition(),
  85             metadata.offset(),
  86             metadata.timestamp(),
  87             now - time
  88         );
  89       }
  90       else
  91       {
  92         // HANDLE ERROR
  93         result.setErrorResult(new ProduceFailure(e));
  94         log.error(
  95             "{} - ERROR key={} timestamp={} latency={}ms: {}",
  96             id,
  97             record.key(),
  98             metadata == null ? -1 : metadata.timestamp(),
  99             now - time,
 100             e.toString()
 101         );
 102       }
 103     });
 104
 105     long now = System.currentTimeMillis();
 106     log.trace(
 107         "{} - Queued #{} key={} latency={}ms",
 108         id,
 109         value,
 110         record.key(),
 111         now - time
 112     );
 113
 114     return result;
 115   }
 116
 117   @PreDestroy
 118   public void destroy() throws ExecutionException, InterruptedException
 119   {
 120     log.info("{} - Destroy!", id);
 121     log.info("{} - Closing the KafkaProducer", id);
 122     producer.close();
 123     log.info("{}: Produced {} messages in total, exiting!", id, produced);
 124   }
 125 }