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.http.HttpStatus;
   8 import org.springframework.web.bind.annotation.*;
   9 import org.springframework.web.context.request.async.DeferredResult;
  10
  11 import javax.annotation.PreDestroy;
  12 import java.math.BigInteger;
  13 import java.util.Properties;
  14 import java.util.concurrent.ExecutionException;
  15
  16
  17 @Slf4j
  18 @RestController
  19 public class RestProducer
  20 {
  21   private final String id;
  22   private final String topic;
  23   private final Integer partition;
  24   private final KafkaProducer<String, String> producer;
  25
  26   private long produced = 0;
  27
  28   public RestProducer(ApplicationProperties properties)
  29   {
  30     this.id = properties.getClientId();
  31     this.topic = properties.getTopic();
  32     this.partition = properties.getPartition();
  33
  34     Properties props = new Properties();
  35     props.put("bootstrap.servers", properties.getBootstrapServer());
  36     props.put("client.id", properties.getClientId());
  37     props.put("acks", properties.getAcks());
  38     props.put("batch.size", properties.getBatchSize());
  39     props.put("delivery.timeout.ms", 20000); // 20 Sekunden
  40     props.put("request.timeout.ms",  10000); // 10 Sekunden
  41     props.put("linger.ms", properties.getLingerMs());
  42     props.put("compression.type", properties.getCompressionType());
  43     props.put("key.serializer", StringSerializer.class.getName());
  44     props.put("value.serializer", StringSerializer.class.getName());
  45
  46     this.producer = new KafkaProducer<>(props);
  47   }
  48
  49   @PostMapping(path = "{key}")
  50   public DeferredResult<ProduceResult> send(
  51       @PathVariable String key,
  52       @RequestHeader(name = "X-id", required = false) Long correlationId,
  53       @RequestBody String value)
  54   {
  55     DeferredResult<ProduceResult> result = new DeferredResult<>();
  56
  57     final long time = System.currentTimeMillis();
  58
  59     final ProducerRecord<String, String> record = new ProducerRecord<>(
  60         topic,  // Topic
  61         partition, // Partition
  62         key,    // Key
  63         value   // Value
  64     );
  65
  66     record.headers().add("source", id.getBytes());
  67     if (correlationId != null)
  68     {
  69       record.headers().add("id", BigInteger.valueOf(correlationId).toByteArray());
  70     }
  71
  72     producer.send(record, (metadata, e) ->
  73     {
  74       long now = System.currentTimeMillis();
  75       if (e == null)
  76       {
  77         // HANDLE SUCCESS
  78         produced++;
  79         result.setResult(new ProduceSuccess(metadata.partition(), metadata.offset()));
  80         log.debug(
  81             "{} - Sent key={} message={} partition={}/{} timestamp={} latency={}ms",
  82             id,
  83             record.key(),
  84             record.value(),
  85             metadata.partition(),
  86             metadata.offset(),
  87             metadata.timestamp(),
  88             now - time
  89         );
  90       }
  91       else
  92       {
  93         // HANDLE ERROR
  94         result.setErrorResult(new ProduceFailure(e));
  95         log.error(
  96             "{} - ERROR key={} timestamp={} latency={}ms: {}",
  97             id,
  98             record.key(),
  99             metadata == null ? -1 : metadata.timestamp(),
 100             now - time,
 101             e.toString()
 102         );
 103       }
 104     });
 105
 106     long now = System.currentTimeMillis();
 107     log.trace(
 108         "{} - Queued #{} key={} latency={}ms",
 109         id,
 110         value,
 111         record.key(),
 112         now - time
 113     );
 114
 115     return result;
 116   }
 117
 118   @ExceptionHandler
 119   @ResponseStatus(HttpStatus.BAD_REQUEST)
 120   public ErrorResponse illegalStateException(IllegalStateException e)
 121   {
 122     return new ErrorResponse(e.getMessage(), HttpStatus.BAD_REQUEST.value());
 123   }
 124
 125   @PreDestroy
 126   public void destroy() throws ExecutionException, InterruptedException
 127   {
 128     log.info("{} - Destroy!", id);
 129     log.info("{} - Closing the KafkaProducer", id);
 130     producer.close();
 131     log.info("{}: Produced {} messages in total, exiting!", id, produced);
 132   }
 133 }