kafka笔记

kafka知识点

controller 调度topic partition rapliacaion 选举等

broke 节点

topic 一个队列一个topic

partition 分区

raplication 副本

groupid 消费组 一条消息 同一个组多个消费者 只能被一个消费者消费

安装kafka

docker-compose安装kafka集群

docker-compose.yml

version: '2'
services:
  zookeeper:
    image: wurstmeister/zookeeper
    ports:
      - "2181:2181"
  kafka:
    image: wurstmeister/kafka
    ports:
      - "9092"
    environment:
      KAFKA_ADVERTISED_HOST_NAME: 192.168.199.149
      KAFKA_ZOOKEEPER_CONNECT: zookeeper:2181
      KAFKA_CREATE_TOPICS: test:1:1
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock

test:1:1 的含义是默认创建一个名字为 test, Partition 和 Replica 数量都为 1 的 Topic.

启动kafka和zookeeper

docker-compose up -d --scale kafka=2 --scale=zookeeper=2 

进入其中一个kafka容器 创建一个topic

Kafka git:(master) kafka-topics --create --topic chat --partitions 3 --zookeeper localhost:2181 --replication-factor 2

新创建的 Topic 名字为 chat, partition 数为 3, replica 数为 2.

查看Topic 是否成功创建:

bash-4.4# kafka-topics.sh --describe --zookeeper 192.168.199.149:2181 | grep chat
Topic:chat	PartitionCount:3	ReplicationFactor:2	Configs:
Topic: chat	Partition: 0	Leader: 1001	Replicas: 1001,1002	Isr: 1001,1002
Topic: chat	Partition: 1	Leader: 1002	Replicas: 1002,1001	Isr: 1002,1001
Topic: chat	Partition: 2	Leader: 1001	Replicas: 1001,1002	Isr: 1001,1002

进入kafka_01发送消息

kafka-console-producer.sh --broker-list localhost:9092 --topic chat

进入kafka_02接收消息

kafka-console-consumer.sh --bootstrap-server localhost:9092 --topic chat --from-beginning

php-kafka

segmentfault.com/a/119000001…

安装扩展 # 先安装rdkfka库文件 git clone github.com/edenhill/li… cd librdkafka/ ./configure make sudo make install

git clone https://github.com/arnaud-lb/php-rdkafka.git
cd php-rdkafka
phpize
./configure
make all -j 5
sudo make install

vim [php]/php.ini
extension=rdkafka.so

producer.php

<?php
$conf = new RdKafka\Conf();
$conf->setDrMsgCb(function ($kafka, $message) {
    file_put_contents("./dr_cb.log", var_export($message, true).PHP_EOL, FILE_APPEND);
});
$conf->setErrorCb(function ($kafka, $err, $reason) {
    file_put_contents("./err_cb.log", sprintf("Kafka error: %s (reason: %s)", rd_kafka_err2str($err), $reason).PHP_EOL, FILE_APPEND);
});

$rk = new RdKafka\Producer($conf);
$rk->setLogLevel(LOG_DEBUG);
$rk->addBrokers("192.168.199.149:32768");

$cf = new RdKafka\TopicConf();
// -1必须等所有brokers同步完成的确认 1当前服务器确认 0不确认，这里如果是0回调里的offset无返回，如果是1和-1会返回offset
// 我们可以利用该机制做消息生产的确认，不过还不是100%，因为有可能会中途kafka服务器挂掉
$cf->set('request.required.acks', 0);
$topic = $rk->newTopic("test", $cf);

$option = 'qkl';
for ($i = 0; $i < 20; $i++) {
    //RD_KAFKA_PARTITION_UA自动选择分区
    //$option可选
    $topic->produce(RD_KAFKA_PARTITION_UA, 0, "qkl . $i", $option);
}


$len = $rk->getOutQLen();
while ($len > 0) {
    $len = $rk->getOutQLen();
    var_dump($len);
    $rk->poll(50);
}

consume.php

<?php
$conf = new RdKafka\Conf();
$conf->setDrMsgCb(function ($kafka, $message) {
    file_put_contents("./c_dr_cb.log", var_export($message, true), FILE_APPEND);
});
$conf->setErrorCb(function ($kafka, $err, $reason) {
    file_put_contents("./err_cb.log", sprintf("Kafka error: %s (reason: %s)", rd_kafka_err2str($err), $reason).PHP_EOL, FILE_APPEND);
});

//设置消费组
$conf->set('group.id', 'myConsumerGroup');

$rk = new RdKafka\Consumer($conf);
$rk->addBrokers("192.168.199.149:32768");

$topicConf = new RdKafka\TopicConf();
$topicConf->set('request.required.acks', 1);
//在interval.ms的时间内自动提交确认、建议不要启动
//$topicConf->set('auto.commit.enable', 1);
$topicConf->set('auto.commit.enable', 0);
$topicConf->set('auto.commit.interval.ms', 100);

// 设置offset的存储为file
//$topicConf->set('offset.store.method', 'file');
// 设置offset的存储为broker
 $topicConf->set('offset.store.method', 'broker');
//$topicConf->set('offset.store.path', __DIR__);

//smallest：简单理解为从头开始消费，其实等价于上面的 earliest
//largest：简单理解为从最新的开始消费，其实等价于上面的 latest
//$topicConf->set('auto.offset.reset', 'smallest');

$topic = $rk->newTopic("test", $topicConf);

// 参数1消费分区0
// RD_KAFKA_OFFSET_BEGINNING 重头开始消费
// RD_KAFKA_OFFSET_STORED 最后一条消费的offset记录开始消费
// RD_KAFKA_OFFSET_END 最后一条消费
//$topic->consumeStart(0, RD_KAFKA_OFFSET_BEGINNING);
//$topic->consumeStart(0, RD_KAFKA_OFFSET_END); //
$topic->consumeStart(0, RD_KAFKA_OFFSET_STORED);

while (true) {
    //参数1表示消费分区，这里是分区0
    //参数2表示同步阻塞多久
    $message = $topic->consume(0, 12 * 1000);
    if (is_null($message)) {
        sleep(1);
        echo "No more messages\n";
        continue;
    }
    switch ($message->err) {
        case RD_KAFKA_RESP_ERR_NO_ERROR:
            var_dump($message);
            break;
        case RD_KAFKA_RESP_ERR__PARTITION_EOF:
            echo "No more messages; will wait for more\n";
            break;
        case RD_KAFKA_RESP_ERR__TIMED_OUT:
            echo "Timed out\n";
            break;
        default:
            throw new \Exception($message->errstr(), $message->err);
            break;
    }
}