[Kafka] Getting Started

[DrMaemi]

MacOS

1. https://www.apache.org/dyn/closer.cgi?path=/kafka/3.7.0/kafka_2.13-3.7.0.tgz 다운받아 압축 해제

   $ tar -xzf kafka_2.13-3.7.0.tgz
   $ cd kafka_2.13-3.7.0

2. ZK 실행 (사전에 설치)

   bin/zkServer.sh start

3. Kafka 실행

   bin/kafka-server-start.sh config/server.properties

4. Topic 생성 등 동작 수행

   bin/kafka-topics.sh --create --partitions 1 --replication-factor 1 --topic quickstart-events --bootstrap-server localhost:9092

5. Topic 에 event publish 해보기

   $ bin/kafka-console-producer.sh --topic quickstart-events --bootstrap-server localhost:9092
   >This is my first event
   [2024-04-09 00:57:37,685] WARN [Producer clientId=console-producer] Error while fetching metadata with correlation id 6 : {quickstart-events=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
   >Is there ?
   >This is my second event
   >This is realtime event publishing

6. Event read 해보기

   $ bin/kafka-console-consumer.sh --topic quickstart-events --from-beginning --bootstrap-server localhost:9092
   This is my first event
   Is there ?
   This is my second event
   This is realtime event publishing

7. Topic describe

   bin/kafka-topics.sh --describe --topic quickstart-events --bootstrap-server localhost:9092
   Topic: quickstart-events    TopicId: j9jxzPlMQUiIcgY4vuLA_w PartitionCount: 1   ReplicationFactor: 1    Configs:
   Topic: quickstart-events    Partition: 0    Leader: 0   Replicas: 0 Isr: 0

8. Consumer group describe

   
   bin/kafka-consumer-groups.sh --all-groups --bootstrap-server localhost:9092 --describe

GROUP TOPIC PARTITION CURRENT-OFFSET LOG-END-OFFSET LAG CONSUMER-ID HOST CLIENT-ID console-consumer-80282 quickstart-events 0 - 4 - console-consumer-e1a1fbfc-acca-4b72-aee2-cea8219d4e54 /192.168.219.102 console-consumer

### Java Kafka Stream Application
- [WordCountDemo.java, *github.com/apache/kafka*](https://github.com/apache/kafka/blob/3.6/streams/examples/src/main/java/org/apache/kafka/streams/examples/wordcount/WordCountDemo.java)
- ["TUTORIAL: WRITE A KAFKA STREAMS APPLICATION," *kafka.apache.org*](https://kafka.apache.org/37/documentation/streams/tutorial)

## A. 참조
- [https://kafka.apache.org/quickstart](https://kafka.apache.org/quickstart)
- [https://kafka.apache.org/documentation/#operations](https://kafka.apache.org/documentation/#operations)

[DrMaemi]

bin/kafka-console-consumer.sh --bootstrap-server localhost:9092 --topic quickstart-events --group test_group --from-beginning

bin/kafka-consumer-groups.sh --bootstrap-server localhost:9092 --all-groups --describe

Consumer group 'console-consumer-36288' has no active members.

GROUP           TOPIC             PARTITION  CURRENT-OFFSET  LOG-END-OFFSET  LAG             CONSUMER-ID                                           HOST            CLIENT-ID
test_group      quickstart-events 2          0               0               0               console-consumer-7627f017-1902-4cbb-8dab-85770a513578 /10.61.44.43    console-consumer
test_group      quickstart-events 1          2               2               0               console-consumer-7627f017-1902-4cbb-8dab-85770a513578 /10.61.44.43    console-consumer
test_group      quickstart-events 0          0               0               0               console-consumer-7627f017-1902-4cbb-8dab-85770a513578 /10.61.44.43    console-consumer