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     // TODO: Fügen Sie die Header zu der Nachricht hinzu
  67
  68     producer.send(record, (metadata, e) ->
  69     {
  70       long now = System.currentTimeMillis();
  71       if (e == null)
  72       {
  73         // HANDLE SUCCESS
  74         produced++;
  75         result.setResult(new ProduceSuccess(metadata.partition(), metadata.offset()));
  76         log.debug(
  77             "{} - Sent key={} message={} partition={}/{} timestamp={} latency={}ms",
  78             id,
  79             record.key(),
  80             record.value(),
  81             metadata.partition(),
  82             metadata.offset(),
  83             metadata.timestamp(),
  84             now - time
  85         );
  86       }
  87       else
  88       {
  89         // HANDLE ERROR
  90         result.setErrorResult(new ProduceFailure(e));
  91         log.error(
  92             "{} - ERROR key={} timestamp={} latency={}ms: {}",
  93             id,
  94             record.key(),
  95             metadata == null ? -1 : metadata.timestamp(),
  96             now - time,
  97             e.toString()
  98         );
  99       }
 100     });
 101
 102     long now = System.currentTimeMillis();
 103     log.trace(
 104         "{} - Queued message with key={} latency={}ms",
 105         id,
 106         record.key(),
 107         now - time
 108     );
 109
 110     return result;
 111   }
 112
 113   @ExceptionHandler
 114   @ResponseStatus(HttpStatus.BAD_REQUEST)
 115   public ErrorResponse illegalStateException(IllegalStateException e)
 116   {
 117     return new ErrorResponse(e.getMessage(), HttpStatus.BAD_REQUEST.value());
 118   }
 119
 120   @PreDestroy
 121   public void destroy() throws ExecutionException, InterruptedException
 122   {
 123     log.info("{} - Destroy!", id);
 124     log.info("{} - Closing the KafkaProducer", id);
 125     producer.close();
 126     log.info("{}: Produced {} messages in total, exiting!", id, produced);
 127   }
 128 }