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.Test;
  15 import org.springframework.beans.factory.annotation.Autowired;
  16 import org.springframework.boot.test.context.ConfigDataApplicationContextInitializer;
  17 import org.springframework.boot.test.context.TestConfiguration;
  18 import org.springframework.context.annotation.Bean;
  19 import org.springframework.context.annotation.Import;
  20 import org.springframework.kafka.test.context.EmbeddedKafka;
  21 import org.springframework.test.context.TestPropertySource;
  22 import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
  23
  24 import java.util.*;
  25 import java.util.concurrent.ExecutorService;
  26 import java.util.function.BiConsumer;
  27 import java.util.function.Consumer;
  28 import java.util.function.Function;
  29 import java.util.stream.Collectors;
  30 import java.util.stream.IntStream;
  31
  32 import static de.juplo.kafka.ApplicationTests.PARTITIONS;
  33 import static de.juplo.kafka.ApplicationTests.TOPIC;
  34 import static org.assertj.core.api.Assertions.assertThat;
  35
  36
  37 @SpringJUnitConfig(initializers = ConfigDataApplicationContextInitializer.class)
  38 @TestPropertySource(
  39                 properties = {
  40                                 "consumer.bootstrap-server=${spring.embedded.kafka.brokers}",
  41                                 "consumer.topic=" + TOPIC })
  42 @EmbeddedKafka(topics = TOPIC, partitions = PARTITIONS)
  43 @Slf4j
  44 class ApplicationTests
  45 {
  46         public static final String TOPIC = "FOO";
  47         public static final int PARTITIONS = 10;
  48
  49
  50         StringSerializer stringSerializer = new StringSerializer();
  51         LongSerializer longSerializer = new LongSerializer();
  52
  53         @Autowired
  54         KafkaProducer<String, Bytes> kafkaProducer;
  55         @Autowired
  56         KafkaConsumer<String, Long> kafkaConsumer;
  57         @Autowired
  58         ApplicationProperties properties;
  59         @Autowired
  60         ExecutorService executor;
  61
  62
  63         @Test
  64         void commitsCurrentOffsetsOnSuccess()
  65         {
  66                 send100Messages(i ->  new Bytes(longSerializer.serialize(TOPIC, i)));
  67
  68                 Set<ConsumerRecord<String, Long>> received = new HashSet<>();
  69                 Map<Integer, Long> offsets = runEndlessConsumer(record ->
  70                 {
  71                         received.add(record);
  72                         if (received.size() == 100)
  73                                 throw new WakeupException();
  74                 });
  75
  76                 check(offsets);
  77         }
  78
  79         @Test
  80         void commitsNoOffsetsOnError()
  81         {
  82                 send100Messages(counter ->
  83                                 counter == 77
  84                                                 ? new Bytes(stringSerializer.serialize(TOPIC, "BOOM!"))
  85                                                 : new Bytes(longSerializer.serialize(TOPIC, counter)));
  86
  87                 Map<Integer, Long> oldOffsets = new HashMap<>();
  88                 doForCurrentOffsets((tp, offset) -> oldOffsets.put(tp.partition(), offset -1));
  89                 Map<Integer, Long> newOffsets = runEndlessConsumer((record) -> {});
  90
  91                 check(oldOffsets);
  92         }
  93
  94
  95         void send100Messages(Function<Long, Bytes> messageGenerator)
  96         {
  97                 long i = 0;
  98
  99                 for (int partition = 0; partition < 10; partition++)
 100                 {
 101                         for (int key = 0; key < 10; key++)
 102                         {
 103                                 Bytes value = messageGenerator.apply(++i);
 104
 105                                 ProducerRecord<String, Bytes> record =
 106                                                 new ProducerRecord<>(
 107                                                                 TOPIC,
 108                                                                 partition,
 109                                                                 Integer.toString(key%2),
 110                                                                 value);
 111
 112                                 kafkaProducer.send(record, (metadata, e) ->
 113                                 {
 114                                         if (metadata != null)
 115                                         {
 116                                                 log.debug(
 117                                                                 "{}|{} - {}={}",
 118                                                                 metadata.partition(),
 119                                                                 metadata.offset(),
 120                                                                 record.key(),
 121                                                                 record.value());
 122                                         }
 123                                         else
 124                                         {
 125                                                 log.warn(
 126                                                                 "Exception for {}={}: {}",
 127                                                                 record.key(),
 128                                                                 record.value(),
 129                                                                 e.toString());
 130                                         }
 131                                 });
 132                         }
 133                 }
 134         }
 135
 136         Map<Integer, Long> runEndlessConsumer(Consumer<ConsumerRecord<String, Long>> consumer)
 137         {
 138                 Map<Integer, Long> offsets = new HashMap<>();
 139                 doForCurrentOffsets((tp, offset) -> offsets.put(tp.partition(), offset -1));
 140                 Consumer<ConsumerRecord<String, Long>> captureOffset = record -> offsets.put(record.partition(), record.offset());
 141                 EndlessConsumer<String, Long> endlessConsumer =
 142                                 new EndlessConsumer<>(
 143                                                 executor,
 144                                                 properties.getClientId(),
 145                                                 properties.getTopic(),
 146                                                 kafkaConsumer,
 147                                                 captureOffset.andThen(consumer));
 148
 149                 endlessConsumer.run();
 150
 151                 return offsets;
 152         }
 153
 154         List<TopicPartition> partitions()
 155         {
 156                 return
 157                                 IntStream
 158                                                 .range(0, PARTITIONS)
 159                                                 .mapToObj(partition -> new TopicPartition(TOPIC, partition))
 160                                                 .collect(Collectors.toList());
 161         }
 162
 163         void doForCurrentOffsets(BiConsumer<TopicPartition, Long> consumer)
 164         {
 165                 kafkaConsumer.assign(partitions());
 166                 partitions().forEach(tp -> consumer.accept(tp, kafkaConsumer.position(tp)));
 167                 kafkaConsumer.unsubscribe();
 168         }
 169
 170         void check(Map<Integer, Long> offsets)
 171         {
 172                 doForCurrentOffsets((tp, offset) ->
 173                 {
 174                         Long expected = offsets.get(tp.partition()) + 1;
 175                         log.debug("Checking, if the offset for {} is {}", tp, expected);
 176                         assertThat(offset).isEqualTo(expected);
 177                 });
 178         }
 179
 180
 181         @TestConfiguration
 182         @Import(ApplicationConfiguration.class)
 183         public static class Configuration
 184         {
 185                 @Bean
 186                 KafkaProducer<String, Bytes> kafkaProducer(ApplicationProperties properties)
 187                 {
 188                         Properties props = new Properties();
 189                         props.put("bootstrap.servers", properties.getBootstrapServer());
 190                         props.put("linger.ms", 100);
 191                         props.put("key.serializer", StringSerializer.class.getName());
 192                         props.put("value.serializer", BytesSerializer.class.getName());
 193
 194                         return new KafkaProducer<>(props);
 195                 }
 196         }
 197 }