juplo.de Git - demos/kafka/training/blob - src/test/java/de/juplo/kafka/ApplicationTests.java

   1 package de.juplo.kafka;
   2
   3 import lombok.extern.slf4j.Slf4j;
   4 import org.apache.kafka.clients.consumer.ConsumerRecord;
   5 import org.apache.kafka.clients.consumer.KafkaConsumer;
   6 import org.apache.kafka.clients.producer.KafkaProducer;
   7 import org.apache.kafka.clients.producer.ProducerRecord;
   8 import org.apache.kafka.common.TopicPartition;
   9 import org.apache.kafka.common.errors.WakeupException;
  10 import org.apache.kafka.common.serialization.BytesSerializer;
  11 import org.apache.kafka.common.serialization.LongSerializer;
  12 import org.apache.kafka.common.serialization.StringSerializer;
  13 import org.apache.kafka.common.utils.Bytes;
  14 import org.junit.jupiter.api.MethodOrderer;
  15 import org.junit.jupiter.api.Order;
  16 import org.junit.jupiter.api.Test;
  17 import org.junit.jupiter.api.TestMethodOrder;
  18 import org.springframework.beans.factory.annotation.Autowired;
  19 import org.springframework.boot.test.context.ConfigDataApplicationContextInitializer;
  20 import org.springframework.boot.test.context.TestConfiguration;
  21 import org.springframework.context.annotation.Bean;
  22 import org.springframework.context.annotation.Import;
  23 import org.springframework.kafka.test.context.EmbeddedKafka;
  24 import org.springframework.test.context.TestPropertySource;
  25 import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
  26
  27 import java.util.*;
  28 import java.util.concurrent.ExecutorService;
  29 import java.util.function.BiConsumer;
  30 import java.util.function.Consumer;
  31 import java.util.function.Function;
  32 import java.util.stream.Collectors;
  33 import java.util.stream.IntStream;
  34
  35 import static de.juplo.kafka.ApplicationTests.PARTITIONS;
  36 import static de.juplo.kafka.ApplicationTests.TOPIC;
  37 import static org.assertj.core.api.Assertions.assertThat;
  38
  39
  40 @SpringJUnitConfig(initializers = ConfigDataApplicationContextInitializer.class)
  41 @TestMethodOrder(MethodOrderer.OrderAnnotation.class)
  42 @TestPropertySource(
  43                 properties = {
  44                                 "consumer.bootstrap-server=${spring.embedded.kafka.brokers}",
  45                                 "consumer.topic=" + TOPIC })
  46 @EmbeddedKafka(topics = TOPIC, partitions = PARTITIONS)
  47 @Slf4j
  48 class ApplicationTests
  49 {
  50         public static final String TOPIC = "FOO";
  51         public static final int PARTITIONS = 10;
  52
  53
  54         StringSerializer stringSerializer = new StringSerializer();
  55         LongSerializer longSerializer = new LongSerializer();
  56
  57         @Autowired
  58         KafkaProducer<String, Bytes> kafkaProducer;
  59         @Autowired
  60         KafkaConsumer<String, Long> kafkaConsumer;
  61         @Autowired
  62         ApplicationProperties properties;
  63         @Autowired
  64         ExecutorService executor;
  65
  66
  67         @Test
  68         @Order(1) // << The poistion pill is not skipped. Hence, this test must run first
  69         void commitsCurrentOffsetsOnSuccess()
  70         {
  71                 send100Messages(i ->  new Bytes(longSerializer.serialize(TOPIC, i)));
  72
  73                 Set<ConsumerRecord<String, Long>> received = new HashSet<>();
  74                 Map<Integer, Long> offsets = runEndlessConsumer(record ->
  75                 {
  76                         received.add(record);
  77                         if (received.size() == 100)
  78                                 throw new WakeupException();
  79                 });
  80
  81                 check(offsets);
  82         }
  83
  84         @Test
  85         @Order(2)
  86         void commitsNoOffsetsOnError()
  87         {
  88                 send100Messages(counter ->
  89                                 counter == 77
  90                                                 ? new Bytes(stringSerializer.serialize(TOPIC, "BOOM!"))
  91                                                 : new Bytes(longSerializer.serialize(TOPIC, counter)));
  92
  93                 Map<Integer, Long> oldOffsets = new HashMap<>();
  94                 doForCurrentOffsets((tp, offset) -> oldOffsets.put(tp.partition(), offset -1));
  95                 Map<Integer, Long> newOffsets = runEndlessConsumer((record) -> {});
  96
  97                 check(oldOffsets);
  98         }
  99
 100
 101         void send100Messages(Function<Long, Bytes> messageGenerator)
 102         {
 103                 long i = 0;
 104
 105                 for (int partition = 0; partition < 10; partition++)
 106                 {
 107                         for (int key = 0; key < 10; key++)
 108                         {
 109                                 Bytes value = messageGenerator.apply(++i);
 110
 111                                 ProducerRecord<String, Bytes> record =
 112                                                 new ProducerRecord<>(
 113                                                                 TOPIC,
 114                                                                 partition,
 115                                                                 Integer.toString(key%2),
 116                                                                 value);
 117
 118                                 kafkaProducer.send(record, (metadata, e) ->
 119                                 {
 120                                         if (metadata != null)
 121                                         {
 122                                                 log.debug(
 123                                                                 "{}|{} - {}={}",
 124                                                                 metadata.partition(),
 125                                                                 metadata.offset(),
 126                                                                 record.key(),
 127                                                                 record.value());
 128                                         }
 129                                         else
 130                                         {
 131                                                 log.warn(
 132                                                                 "Exception for {}={}: {}",
 133                                                                 record.key(),
 134                                                                 record.value(),
 135                                                                 e.toString());
 136                                         }
 137                                 });
 138                         }
 139                 }
 140         }
 141
 142         Map<Integer, Long> runEndlessConsumer(Consumer<ConsumerRecord<String, Long>> consumer)
 143         {
 144                 Map<Integer, Long> offsets = new HashMap<>();
 145                 doForCurrentOffsets((tp, offset) -> offsets.put(tp.partition(), offset -1));
 146                 Consumer<ConsumerRecord<String, Long>> captureOffset = record -> offsets.put(record.partition(), record.offset());
 147                 EndlessConsumer<String, Long> endlessConsumer =
 148                                 new EndlessConsumer<>(
 149                                                 executor,
 150                                                 properties.getClientId(),
 151                                                 properties.getTopic(),
 152                                                 kafkaConsumer,
 153                                                 captureOffset.andThen(consumer));
 154
 155                 endlessConsumer.run();
 156
 157                 return offsets;
 158         }
 159
 160         List<TopicPartition> partitions()
 161         {
 162                 return
 163                                 IntStream
 164                                                 .range(0, PARTITIONS)
 165                                                 .mapToObj(partition -> new TopicPartition(TOPIC, partition))
 166                                                 .collect(Collectors.toList());
 167         }
 168
 169         void doForCurrentOffsets(BiConsumer<TopicPartition, Long> consumer)
 170         {
 171                 kafkaConsumer.assign(partitions());
 172                 partitions().forEach(tp -> consumer.accept(tp, kafkaConsumer.position(tp)));
 173                 kafkaConsumer.unsubscribe();
 174         }
 175
 176         void check(Map<Integer, Long> offsets)
 177         {
 178                 doForCurrentOffsets((tp, offset) ->
 179                 {
 180                         Long expected = offsets.get(tp.partition()) + 1;
 181                         log.debug("Checking, if the offset for {} is {}", tp, expected);
 182                         assertThat(offset).isEqualTo(expected);
 183                 });
 184         }
 185
 186
 187         @TestConfiguration
 188         @Import(ApplicationConfiguration.class)
 189         public static class Configuration
 190         {
 191                 @Bean
 192                 KafkaProducer<String, Bytes> kafkaProducer(ApplicationProperties properties)
 193                 {
 194                         Properties props = new Properties();
 195                         props.put("bootstrap.servers", properties.getBootstrapServer());
 196                         props.put("linger.ms", 100);
 197                         props.put("key.serializer", StringSerializer.class.getName());
 198                         props.put("value.serializer", BytesSerializer.class.getName());
 199
 200                         return new KafkaProducer<>(props);
 201                 }
 202         }
 203 }