Kafka

一、單例模式安裝

1、準備安裝檔案kafka_2.11-0.11.0.0.tgz，放到linux伺服器，並解壓

2、vim config/server.properties

3、修改項如下:   host.name=你的ip   listeners=PLAINTEXT://你的ip:9092   advertised.listeners=PLAINTEXT://你的ip:9092   zookeeper.connect=zookeeper叢集地址

4、啟動kafka    ./bin/kafka-server-start.sh -daemon config/server.properties &

5、測試

（1）建立topic:my-first-topic

./kafka-topics.sh --create --zookeeper 192.168.85.130:2181 --topic my-first-topic --partitions 1 --replication-factor 1

（2）啟動consumer 

./kafka-console-consumer.sh --bootstrap-server 192.168.85.130:9092 --topic my-first-topic --from-beginning

本指令執行完畢後暫時沒有任何輸出。

（3）啟動producer，這裡需要新開一個視窗

./kafka-console-producer.sh --broker-list 192.168.85.130:9092 --topic my-first-topic

啟動成功後，在本視窗輸入任意內容，回車傳送後，可以上consumer視窗接受到相同的訊息。

6、java程式碼測試

//新建topic
public class TestKafka {
    public static void main(String[] arg){
        Properties prop = new Properties();
        prop.put("bootstrap.servers","192.168.85.130:9092");
        AdminClient adminClient = AdminClient.create(prop);
        List<NewTopic> topicList = new ArrayList<>();
        NewTopic topic = new NewTopic("my-first-topic", 1, (short)1);
        topicList.add(topic);
        adminClient.createTopics(topicList);
    }
}

//Producer 
public class MyProducer {
    public static void main(String[] args){
        Properties props = new Properties();
        props.put("bootstrap.servers", "192.168.85.130:9092");
        props.put("acks", "all");
        props.put("retries", 0);
        props.put("batch.size", 16384);
        props.put("linger.ms", 1);
        props.put("buffer.memory", 33554432);
        props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");

        Producer<String, String> producer = new KafkaProducer<String, String>(props);
        for (int i = 0; i < 10; i++)
            producer.send(new ProducerRecord<String, String>("my-first-topic", Integer.toString(i), Integer.toString(i)));
        producer.close();
    }
}

//Consumer

public class MyConsumer {
    public static void main(String[] args){
        Properties props = new Properties();
        props.put("bootstrap.servers", "192.168.85.130:9092");
        props.put("group.id", "my-first-topic");
        props.put("enable.auto.commit", "true");
        props.put("auto.commit.interval.ms", "1000");
        props.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        props.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        final KafkaConsumer<String, String> consumer = new KafkaConsumer<String,String>(props);
        consumer.subscribe(Arrays.asList("my-first-topic"),new ConsumerRebalanceListener() {
            public void onPartitionsRevoked(Collection<TopicPartition> collection) {
            }
            public void onPartitionsAssigned(Collection<TopicPartition> collection) {
                //將偏移設定到最開始
                consumer.seekToBeginning(collection);
            }
        });
        while (true) {
            ConsumerRecords<String, String> records = consumer.poll(100);
            for (ConsumerRecord<String, String> record : records)
                System.out.printf("offset = %d, key = %s, value = %s%n", record.offset(), record.key(), record.value());
        }
    }
}