Der Rest-Producer schreibt in eine fixe Partition, wenn so konfiguriert
[demos/kafka/training] / 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.util.Properties;
12 import java.util.concurrent.ExecutionException;
13
14
15 @Slf4j
16 @RestController
17 public class RestProducer
18 {
19   private final String id;
20   private final String topic;
21   private final Integer partition;
22   private final KafkaProducer<String, String> producer;
23
24   private long produced = 0;
25
26   public RestProducer(ApplicationProperties properties)
27   {
28     this.id = properties.getClientId();
29     this.topic = properties.getTopic();
30     this.partition = properties.getPartition();
31
32     Properties props = new Properties();
33     props.put("bootstrap.servers", properties.getBootstrapServer());
34     props.put("client.id", properties.getClientId());
35     props.put("acks", properties.getAcks());
36     props.put("batch.size", properties.getBatchSize());
37     props.put("delivery.timeout.ms", 20000); // 20 Sekunden
38     props.put("request.timeout.ms",  10000); // 10 Sekunden
39     props.put("linger.ms", properties.getLingerMs());
40     props.put("compression.type", properties.getCompressionType());
41     props.put("key.serializer", StringSerializer.class.getName());
42     props.put("value.serializer", StringSerializer.class.getName());
43
44     this.producer = new KafkaProducer<>(props);
45   }
46
47   @PostMapping(path = "{key}")
48   public DeferredResult<ProduceResult> send(
49       @PathVariable String key,
50       @RequestBody String value)
51   {
52     DeferredResult<ProduceResult> result = new DeferredResult<>();
53
54     final long time = System.currentTimeMillis();
55
56     final ProducerRecord<String, String> record = new ProducerRecord<>(
57         topic,  // Topic
58         partition, // Partition
59         key,    // Key
60         value   // Value
61     );
62
63     producer.send(record, (metadata, e) ->
64     {
65       long now = System.currentTimeMillis();
66       if (e == null)
67       {
68         // HANDLE SUCCESS
69         produced++;
70         result.setResult(new ProduceSuccess(metadata.partition(), metadata.offset()));
71         log.debug(
72             "{} - Sent key={} message={} partition={}/{} timestamp={} latency={}ms",
73             id,
74             record.key(),
75             record.value(),
76             metadata.partition(),
77             metadata.offset(),
78             metadata.timestamp(),
79             now - time
80         );
81       }
82       else
83       {
84         // HANDLE ERROR
85         result.setErrorResult(new ProduceFailure(e));
86         log.error(
87             "{} - ERROR key={} timestamp={} latency={}ms: {}",
88             id,
89             record.key(),
90             metadata == null ? -1 : metadata.timestamp(),
91             now - time,
92             e.toString()
93         );
94       }
95     });
96
97     long now = System.currentTimeMillis();
98     log.trace(
99         "{} - Queued #{} key={} latency={}ms",
100         id,
101         value,
102         record.key(),
103         now - time
104     );
105
106     return result;
107   }
108
109   @PreDestroy
110   public void destroy() throws ExecutionException, InterruptedException
111   {
112     log.info("{} - Destroy!", id);
113     log.info("{} - Closing the KafkaProducer", id);
114     producer.close();
115     log.info("{}: Produced {} messages in total, exiting!", id, produced);
116   }
117 }