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BAEL-1426 Adding a message generator and updated Word Count Transactional App

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This commit is contained in:
Chirag Dewan 2018-09-22 15:22:06 +05:30
parent 5d7cc11745
commit d9724fc153
3 changed files with 101 additions and 18 deletions
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56
libraries/src/main/java/com/baeldung/kafka/TransactionalMessageProducer.java Normal file
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@ -0,0 +1,56 @@
package com.baeldung.kafka;
import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.ProducerRecord;
import org.apache.kafka.common.KafkaException;
import java.util.Properties;
import java.util.stream.Stream;
import static org.apache.kafka.clients.consumer.ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG;
import static org.apache.kafka.clients.producer.ProducerConfig.ENABLE_IDEMPOTENCE_CONFIG;
import static org.apache.kafka.clients.producer.ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG;
import static org.apache.kafka.clients.producer.ProducerConfig.TRANSACTIONAL_ID_CONFIG;
import static org.apache.kafka.clients.producer.ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG;
public class TransactionalMessageProducer {
private static final String DATA_MESSAGE_1 = "Put any space separated data here for count";
private static final String DATA_MESSAGE_2 = "Output will contain count of every word in the message";
public static void main(String[] args) {
KafkaProducer<String, String> producer = createKafkaProducer();
producer.initTransactions();
try{
producer.beginTransaction();
Stream.of(DATA_MESSAGE_1, DATA_MESSAGE_2).forEach(s -> producer.send(
new ProducerRecord<String, String>("input", null, s)));
producer.commitTransaction();
}catch (KafkaException e){
producer.abortTransaction();
}
}
private static KafkaProducer<String, String> createKafkaProducer() {
Properties props = new Properties();
props.put(BOOTSTRAP_SERVERS_CONFIG, "localhost:9092");
props.put(ENABLE_IDEMPOTENCE_CONFIG, "true");
props.put(TRANSACTIONAL_ID_CONFIG, "prod-0");
props.put(KEY_SERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringSerializer");
props.put(VALUE_SERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringSerializer");
return new KafkaProducer(props);
}
}

39
libraries/src/main/java/com/baeldung/kafka/TransactionalApp.java → libraries/src/main/java/com/baeldung/kafka/TransactionalWordCount.java
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@ -14,6 +14,8 @@ import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import static java.time.Duration.ofSeconds;
import static java.util.Collections.singleton;
@ -21,16 +23,16 @@ import static org.apache.kafka.clients.consumer.ConsumerConfig.*;
import static org.apache.kafka.clients.consumer.ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG;
import static org.apache.kafka.clients.producer.ProducerConfig.*;
public class TransactionalApp {
public class TransactionalWordCount {
private static final String CONSUMER_GROUP_ID = "test";
private static final String CONSUMER_GROUP_ID = "my-group-id";
private static final String OUTPUT_TOPIC = "output";
private static final String INPUT_TOPIC = "input";
public static void main(String[] args) {
KafkaConsumer<String, String> consumer = initConsumer();
KafkaProducer<String, String> producer = initProducer();
KafkaConsumer<String, String> consumer = createKafkaConsumer();
KafkaProducer<String, String> producer = createKafkaProducer();
producer.initTransactions();
@ -38,12 +40,17 @@ public class TransactionalApp {
while (true) {
ConsumerRecords<String, String> records = consumer.poll(ofSeconds(20));
ConsumerRecords<String, String> records = consumer.poll(ofSeconds(60));
Map<String, Integer> wordCountMap = records.records(new TopicPartition(INPUT_TOPIC, 0))
.stream()
.flatMap(record -> Stream.of(record.value().split(" ")))
.map(word -> Tuple.of(word, 1))
.collect(Collectors.toMap(tuple -> tuple.getKey(), t1 -> t1.getValue(), (v1, v2) -> v1 + v2));
producer.beginTransaction();
for (ConsumerRecord record : records)
producer.send(new ProducerRecord(OUTPUT_TOPIC, record));
wordCountMap.forEach((key, value) -> producer.send(new ProducerRecord<String, String>(OUTPUT_TOPIC, key, value.toString())));
Map<TopicPartition, OffsetAndMetadata> offsetsToCommit = new HashMap<>();
@ -51,7 +58,7 @@ public class TransactionalApp {
List<ConsumerRecord<String, String>> partitionedRecords = records.records(partition);
long offset = partitionedRecords.get(partitionedRecords.size() - 1).offset();
offsetsToCommit.put(partition, new OffsetAndMetadata(offset));
offsetsToCommit.put(partition, new OffsetAndMetadata(offset + 1));
}
producer.sendOffsetsToTransaction(offsetsToCommit, CONSUMER_GROUP_ID);
@ -68,11 +75,12 @@ public class TransactionalApp {
}
private static KafkaConsumer<String, String> initConsumer() {
private static KafkaConsumer<String, String> createKafkaConsumer() {
Properties props = new Properties();
props.put(BOOTSTRAP_SERVERS_CONFIG, "localhost:9092");
props.put(GROUP_ID_CONFIG, CONSUMER_GROUP_ID);
props.put(ENABLE_AUTO_COMMIT_CONFIG, "false");
props.put(ISOLATION_LEVEL_CONFIG, "read_committed");
props.put(KEY_DESERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringDeserializer");
props.put(VALUE_DESERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringDeserializer");
@ -81,19 +89,14 @@ public class TransactionalApp {
return consumer;
}
private static KafkaProducer<String, String> initProducer() {
private static KafkaProducer<String, String> createKafkaProducer() {
Properties props = new Properties();
props.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, "localhost:9092");
props.put(ACKS_CONFIG, "all");
props.put(RETRIES_CONFIG, 3);
props.put(BATCH_SIZE_CONFIG, 16384);
props.put(LINGER_MS_CONFIG, 1);
props.put(BUFFER_MEMORY_CONFIG, 33554432);
props.put(BOOTSTRAP_SERVERS_CONFIG, "localhost:9092");
props.put(ENABLE_IDEMPOTENCE_CONFIG, "true");
props.put(TRANSACTIONAL_ID_CONFIG, "prod-1");
props.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringSerializer");
props.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringSerializer");
props.put(KEY_SERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringSerializer");
props.put(VALUE_SERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringSerializer");
return new KafkaProducer(props);

24
libraries/src/main/java/com/baeldung/kafka/Tuple.java Normal file
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@ -0,0 +1,24 @@
package com.baeldung.kafka;
public class Tuple {
private String key;
private Integer value;
private Tuple(String key, Integer value) {
this.key = key;
this.value = value;
}
public static Tuple of(String key, Integer value){
return new Tuple(key,value);
}
public String getKey() {
return key;
}
public Integer getValue() {
return value;
}
}