<div align="center">
<p>
    <img width="480" src="https://www.andplus.com/hs-fs/hubfs/kafkalogo.jpg?&name=kafkalogo.jpg">
</p>
<h1>Apache Kafka 공부</h1>
    <h5>v2.13-2.6.0</h5>

[Apache Kafka](https://kafka.apache.org/)

</div>

## 설치
[Kafka 다운로드](https://kafka.apache.org/downloads)

*Download Binary*

## 실행

zookeeper & kafka 서버 실행

```console

WIN10@DESKTOP:~$ zookeeper-server-start config/zookeeper.properties

WIN10@DESKTOP:~$ kafka-server-start config/server.properties

```

## CLI 명령어

1. 토픽 만들기 (파티션=3, 복제 계수=2)
```console
WIN10@DESKTOP:~$ kafka-topics --zookeeper localhost:2181 --topic first-topic --create --partitions 3 --replication-factor 2
```

2. 토픽 목록 보기
```console
WIN10@DESKTOP:~$ kafka-topics --zookeeper localhost:2181 --list

first-topic
second-topic
```

3. 토픽 설정 보기
```console
WIN10@DESKTOP:~$ kafka-topics --zookeeper localhost:2181 --topic first-topic --describe

Topic: first-topic      PartitionCount: 3       ReplicationFactor: 1    Configs:
        Topic: first-topic      Partition: 0    Leader: 0       Replicas: 0     Isr: 0
        Topic: first-topic      Partition: 1    Leader: 0       Replicas: 0     Isr: 0
        Topic: first-topic      Partition: 2    Leader: 0       Replicas: 0     Isr: 0
```

4. 토픽 컨슈머 (프로듀서 작동할 때)
```console
WIN10@DESKTOP:~$ kafka-console-consumer --bootstrap-server localhost:9092 --topic first-topic
```

5. 토픽 그룹 이름 설정 및 컨슈머
```console
WIN10@DESKTOP:~$ kafka-console-consumer --bootstrap-server localhost:9092 --topic first-topic --group group-one
```

6. 토픽 컨슈머 그룹 목록
```console
WIN10@DESKTOP:~$ kafka-consumer-groups --bootstrap-server localhost:9092 --list

group-one
```

7. 토픽 오프셋 초기화
```console
WIN10@DESKTOP:~$ kafka-consumer-groups --bootstrap-server localhost:9092 --topic first-topic --group group-one --reset-offsets --to-earliest --execute

GROUP                          TOPIC                          PARTITION  NEW-OFFSET
group-one                      first-topic                    0          0
group-one                      first-topic                    1          0
group-one                      first-topic                    2          0

```

## 목차

<table>
    <tr><td width=40% valign=top>
        
* Kafka
    * [Simple Producer](https://github.com/Alfex4936/kafka-Studies/blob/main/src/main/java/csw/kafka/study/lesson1/ProducerDemo.java)
</td></tr>
</table>