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.errors.RecordDeserializationException;
10 import org.apache.kafka.common.serialization.*;
11 import org.apache.kafka.common.utils.Bytes;
12 import org.junit.jupiter.api.*;
13 import org.springframework.beans.factory.annotation.Autowired;
14 import org.springframework.boot.test.context.ConfigDataApplicationContextInitializer;
15 import org.springframework.boot.test.context.TestConfiguration;
16 import org.springframework.context.annotation.Bean;
17 import org.springframework.context.annotation.Import;
18 import org.springframework.kafka.test.context.EmbeddedKafka;
19 import org.springframework.test.context.TestPropertySource;
20 import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
22 import java.time.Duration;
24 import java.util.concurrent.ExecutionException;
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;
32 import static de.juplo.kafka.ApplicationTests.PARTITIONS;
33 import static de.juplo.kafka.ApplicationTests.TOPIC;
34 import static org.assertj.core.api.Assertions.*;
35 import static org.awaitility.Awaitility.*;
38 @SpringJUnitConfig(initializers = ConfigDataApplicationContextInitializer.class)
39 @TestMethodOrder(MethodOrderer.OrderAnnotation.class)
42 "consumer.bootstrap-server=${spring.embedded.kafka.brokers}",
43 "consumer.topic=" + TOPIC })
44 @EmbeddedKafka(topics = TOPIC, partitions = PARTITIONS)
46 class ApplicationTests
48 public static final String TOPIC = "FOO";
49 public static final int PARTITIONS = 10;
52 StringSerializer stringSerializer = new StringSerializer();
55 Serializer valueSerializer;
57 KafkaProducer<String, Bytes> kafkaProducer;
59 KafkaConsumer<String, Long> kafkaConsumer;
61 KafkaConsumer<Bytes, Bytes> offsetConsumer;
63 ApplicationProperties properties;
65 ExecutorService executor;
67 Consumer<ConsumerRecord<String, Long>> testHandler;
68 EndlessConsumer<String, Long> endlessConsumer;
69 Map<TopicPartition, Long> oldOffsets;
70 Map<TopicPartition, Long> newOffsets;
71 Set<ConsumerRecord<String, Long>> receivedRecords;
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(valueSerializer.serialize(TOPIC, i)));
82 await("100 records received")
83 .atMost(Duration.ofSeconds(30))
84 .until(() -> receivedRecords.size() >= 100);
86 await("Offsets committed")
87 .atMost(Duration.ofSeconds(10))
90 checkSeenOffsetsForProgress();
91 compareToCommitedOffsets(newOffsets);
94 assertThatExceptionOfType(IllegalStateException.class)
95 .isThrownBy(() -> endlessConsumer.exitStatus())
96 .describedAs("Consumer should still be running");
101 void commitsOffsetOfErrorForReprocessingOnError()
103 send100Messages(counter ->
105 ? new Bytes(stringSerializer.serialize(TOPIC, "BOOM!"))
106 : new Bytes(valueSerializer.serialize(TOPIC, counter)));
108 await("Consumer failed")
109 .atMost(Duration.ofSeconds(30))
110 .until(() -> !endlessConsumer.running());
112 checkSeenOffsetsForProgress();
113 compareToCommitedOffsets(newOffsets);
115 endlessConsumer.start();
116 await("Consumer failed")
117 .atMost(Duration.ofSeconds(30))
118 .until(() -> !endlessConsumer.running());
120 checkSeenOffsetsForProgress();
121 compareToCommitedOffsets(newOffsets);
122 assertThat(receivedRecords.size())
123 .describedAs("Received not all sent events")
126 assertThatNoException()
127 .describedAs("Consumer should not be running")
128 .isThrownBy(() -> endlessConsumer.exitStatus());
129 assertThat(endlessConsumer.exitStatus())
130 .describedAs("Consumer should have exited abnormally")
131 .containsInstanceOf(RecordDeserializationException.class);
135 /** Helper methods for the verification of expectations */
137 void compareToCommitedOffsets(Map<TopicPartition, Long> offsetsToCheck)
139 doForCurrentOffsets((tp, offset) ->
141 Long expected = offsetsToCheck.get(tp) + 1;
142 log.debug("Checking, if the offset for {} is {}", tp, expected);
144 .describedAs("Committed offset corresponds to the offset of the consumer")
145 .isEqualTo(expected);
149 void checkSeenOffsetsForProgress()
151 // Be sure, that some messages were consumed...!
152 Set<TopicPartition> withProgress = new HashSet<>();
153 partitions().forEach(tp ->
155 Long oldOffset = oldOffsets.get(tp);
156 Long newOffset = newOffsets.get(tp);
157 if (!oldOffset.equals(newOffset))
159 log.debug("Progress for {}: {} -> {}", tp, oldOffset, newOffset);
160 withProgress.add(tp);
163 assertThat(withProgress)
164 .describedAs("Some offsets must have changed, compared to the old offset-positions")
169 /** Helper methods for setting up and running the tests */
171 void doForCurrentOffsets(BiConsumer<TopicPartition, Long> consumer)
173 offsetConsumer.assign(partitions());
174 partitions().forEach(tp -> consumer.accept(tp, offsetConsumer.position(tp)));
175 offsetConsumer.unsubscribe();
178 List<TopicPartition> partitions()
182 .range(0, PARTITIONS)
183 .mapToObj(partition -> new TopicPartition(TOPIC, partition))
184 .collect(Collectors.toList());
188 void send100Messages(Function<Long, Bytes> messageGenerator)
192 for (int partition = 0; partition < 10; partition++)
194 for (int key = 0; key < 10; key++)
196 Bytes value = messageGenerator.apply(++i);
198 ProducerRecord<String, Bytes> record =
199 new ProducerRecord<>(
202 Integer.toString(key%2),
205 kafkaProducer.send(record, (metadata, e) ->
207 if (metadata != null)
211 metadata.partition(),
219 "Exception for {}={}: {}",
233 testHandler = record -> {} ;
235 oldOffsets = new HashMap<>();
236 newOffsets = new HashMap<>();
237 receivedRecords = new HashSet<>();
239 doForCurrentOffsets((tp, offset) ->
241 oldOffsets.put(tp, offset - 1);
242 newOffsets.put(tp, offset - 1);
245 Consumer<ConsumerRecord<String, Long>> captureOffsetAndExecuteTestHandler =
249 new TopicPartition(record.topic(), record.partition()),
251 receivedRecords.add(record);
252 testHandler.accept(record);
256 new EndlessConsumer<>(
258 properties.getClientId(),
259 properties.getTopic(),
261 captureOffsetAndExecuteTestHandler);
263 endlessConsumer.start();
271 endlessConsumer.stop();
275 log.info("Exception while stopping the consumer: {}", e.toString());
281 @Import(ApplicationConfiguration.class)
282 public static class Configuration
285 Serializer<Long> serializer()
287 return new LongSerializer();
291 KafkaProducer<String, Bytes> kafkaProducer(ApplicationProperties properties)
293 Properties props = new Properties();
294 props.put("bootstrap.servers", properties.getBootstrapServer());
295 props.put("linger.ms", 100);
296 props.put("key.serializer", StringSerializer.class.getName());
297 props.put("value.serializer", BytesSerializer.class.getName());
299 return new KafkaProducer<>(props);
303 KafkaConsumer<Bytes, Bytes> offsetConsumer(ApplicationProperties properties)
305 Properties props = new Properties();
306 props.put("bootstrap.servers", properties.getBootstrapServer());
307 props.put("client.id", "OFFSET-CONSUMER");
308 props.put("group.id", properties.getGroupId());
309 props.put("key.deserializer", BytesDeserializer.class.getName());
310 props.put("value.deserializer", BytesDeserializer.class.getName());
312 return new KafkaConsumer<>(props);