1 package de.juplo.kafka;
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.serialization.BytesDeserializer;
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.*;
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;
24 import java.time.Duration;
26 import java.util.concurrent.ExecutionException;
27 import java.util.concurrent.ExecutorService;
28 import java.util.function.BiConsumer;
29 import java.util.function.Consumer;
30 import java.util.function.Function;
31 import java.util.stream.Collectors;
32 import java.util.stream.IntStream;
34 import static de.juplo.kafka.ApplicationTests.PARTITIONS;
35 import static de.juplo.kafka.ApplicationTests.TOPIC;
36 import static org.assertj.core.api.Assertions.assertThat;
37 import static org.awaitility.Awaitility.*;
40 @SpringJUnitConfig(initializers = ConfigDataApplicationContextInitializer.class)
41 @TestMethodOrder(MethodOrderer.OrderAnnotation.class)
44 "consumer.bootstrap-server=${spring.embedded.kafka.brokers}",
45 "consumer.topic=" + TOPIC })
46 @EmbeddedKafka(topics = TOPIC, partitions = PARTITIONS)
48 class ApplicationTests
50 public static final String TOPIC = "FOO";
51 public static final int PARTITIONS = 10;
54 StringSerializer stringSerializer = new StringSerializer();
55 LongSerializer longSerializer = new LongSerializer();
58 KafkaProducer<String, Bytes> kafkaProducer;
60 KafkaConsumer<String, Long> kafkaConsumer;
62 KafkaConsumer<Bytes, Bytes> offsetConsumer;
64 ApplicationProperties properties;
66 ExecutorService executor;
68 Consumer<ConsumerRecord<String, Long>> testHandler;
69 EndlessConsumer<String, Long> endlessConsumer;
70 Map<TopicPartition, Long> oldOffsets;
71 Map<TopicPartition, Long> newOffsets;
77 @Order(1) // << The poistion pill is not skipped. Hence, this test must run first
78 void commitsCurrentOffsetsOnSuccess() throws ExecutionException, InterruptedException
80 send100Messages(i -> new Bytes(longSerializer.serialize(TOPIC, i)));
82 Set<ConsumerRecord<String, Long>> received = new HashSet<>();
83 testHandler = record -> received.add(record);
85 endlessConsumer.start();
87 await("100 records received")
88 .atMost(Duration.ofSeconds(30))
89 .until(() -> received.size() >= 100);
91 await("Offsets committed")
92 .atMost(Duration.ofSeconds(10))
95 checkSeenOffsetsForProgress();
96 compareToCommitedOffsets(newOffsets);
102 void commitsOffsetOfErrorForReprocessingOnError()
104 send100Messages(counter ->
106 ? new Bytes(stringSerializer.serialize(TOPIC, "BOOM!"))
107 : new Bytes(longSerializer.serialize(TOPIC, counter)));
109 Set<ConsumerRecord<String, Long>> received = new HashSet<>();
110 testHandler = record -> received.add(record);
112 endlessConsumer.start();
114 await("Consumer failed")
115 .atMost(Duration.ofSeconds(30))
116 .until(() -> !endlessConsumer.running());
118 checkSeenOffsetsForProgress();
119 compareToCommitedOffsets(newOffsets);
121 endlessConsumer.start();
122 await("Consumer failed")
123 .atMost(Duration.ofSeconds(30))
124 .until(() -> !endlessConsumer.running());
126 checkSeenOffsetsForProgress();
127 compareToCommitedOffsets(newOffsets);
128 assertThat(received.size())
129 .describedAs("Received not all sent events")
134 /** Helper methods for the verification of expectations */
136 void compareToCommitedOffsets(Map<TopicPartition, Long> offsetsToCheck)
138 doForCurrentOffsets((tp, offset) ->
140 Long expected = offsetsToCheck.get(tp) + 1;
141 log.debug("Checking, if the offset for {} is {}", tp, expected);
143 .describedAs("Committed offset corresponds to the offset of the consumer")
144 .isEqualTo(expected);
148 void checkSeenOffsetsForProgress()
150 // Be sure, that some messages were consumed...!
151 Set<TopicPartition> withProgress = new HashSet<>();
152 partitions().forEach(tp ->
154 Long oldOffset = oldOffsets.get(tp);
155 Long newOffset = newOffsets.get(tp);
156 if (!oldOffset.equals(newOffset))
158 log.debug("Progress for {}: {} -> {}", tp, oldOffset, newOffset);
159 withProgress.add(tp);
162 assertThat(withProgress)
163 .describedAs("Some offsets must have changed, compared to the old offset-positions")
168 /** Helper methods for setting up and running the tests */
170 void doForCurrentOffsets(BiConsumer<TopicPartition, Long> consumer)
172 offsetConsumer.assign(partitions());
173 partitions().forEach(tp -> consumer.accept(tp, offsetConsumer.position(tp)));
174 offsetConsumer.unsubscribe();
177 List<TopicPartition> partitions()
181 .range(0, PARTITIONS)
182 .mapToObj(partition -> new TopicPartition(TOPIC, partition))
183 .collect(Collectors.toList());
187 void send100Messages(Function<Long, Bytes> messageGenerator)
191 for (int partition = 0; partition < 10; partition++)
193 for (int key = 0; key < 10; key++)
195 Bytes value = messageGenerator.apply(++i);
197 ProducerRecord<String, Bytes> record =
198 new ProducerRecord<>(
201 Integer.toString(key%2),
204 kafkaProducer.send(record, (metadata, e) ->
206 if (metadata != null)
210 metadata.partition(),
218 "Exception for {}={}: {}",
232 testHandler = record -> {} ;
234 oldOffsets = new HashMap<>();
235 newOffsets = new HashMap<>();
237 doForCurrentOffsets((tp, offset) ->
239 oldOffsets.put(tp, offset - 1);
240 newOffsets.put(tp, offset - 1);
243 Consumer<ConsumerRecord<String, Long>> captureOffsetAndExecuteTestHandler =
247 new TopicPartition(record.topic(), record.partition()),
249 testHandler.accept(record);
253 new EndlessConsumer<>(
255 properties.getClientId(),
256 properties.getTopic(),
258 captureOffsetAndExecuteTestHandler);
266 endlessConsumer.stop();
270 log.info("Exception while stopping the consumer: {}", e.toString());
276 @Import(ApplicationConfiguration.class)
277 public static class Configuration
280 KafkaProducer<String, Bytes> kafkaProducer(ApplicationProperties properties)
282 Properties props = new Properties();
283 props.put("bootstrap.servers", properties.getBootstrapServer());
284 props.put("linger.ms", 100);
285 props.put("key.serializer", StringSerializer.class.getName());
286 props.put("value.serializer", BytesSerializer.class.getName());
288 return new KafkaProducer<>(props);
292 KafkaConsumer<Bytes, Bytes> offsetConsumer(ApplicationProperties properties)
294 Properties props = new Properties();
295 props.put("bootstrap.servers", properties.getBootstrapServer());
296 props.put("client.id", "OFFSET-CONSUMER");
297 props.put("group.id", properties.getGroupId());
298 props.put("key.deserializer", BytesDeserializer.class.getName());
299 props.put("value.deserializer", BytesDeserializer.class.getName());
301 return new KafkaConsumer<>(props);