This topic describes how a PHP client uses SDK for PHP to connect to the default endpoint of Message Queue for Apache Kafka and send and subscribe to messages in a virtual private cloud (VPC).

Prerequisites

Install the C ++ library

  1. Run the following command to switch to the yum repository directory /etc/yum.repos.d/:
    cd /etc/yum.repos.d/
  2. Create a yum repository configuration file confluent.repo.
    [Confluent.dist]
    name=Confluent repository (dist)
    baseurl=https://packages.confluent.io/rpm/5.1/7
    gpgcheck=1
    gpgkey=https://packages.confluent.io/rpm/5.1/archive.key
    enabled=1
    
    [Confluent]
    name=Confluent repository
    baseurl=https://packages.confluent.io/rpm/5.1
    gpgcheck=1
    gpgkey=https://packages.confluent.io/rpm/5.1/archive.key
    enabled=1
  3. Run the following command to install the C ++ library:
    yum install librdkafka-devel

Install the PHP library

  1. Run the following command to install the PHP library:
    pecl install rdkafka
  2. In the PHP initialization file php.ini, add the following line to enable Kafka extensions:
    extension=rdkafka.so

Prepare configurations

Create a configuration file setting.php.
<? php

return [
    'bootstrap_servers' => "xxx:xx,xxx:xx",
    'topic_name' => 'xxx',
    'consumer_id' => 'xxx'
];
Parameter Description
bootstrap_servers The default endpoint of the Message Queue for Apache Kafka instance. You can obtain the default endpoint in the Basic Information section of the Instance Details page in the Message Queue for Apache Kafka console.
topic_name The name of the topic. You can obtain the name of the topic on the Topics page in the Message Queue for Apache Kafka console.
consumer_id The name of the consumer group. You can obtain the name of the consumer group on the Consumer Groups page in the Message Queue for Apache Kafka console.

Send messages

  1. Create a message sender kafka-producer.php.
    <? php
    
    $setting = require __DIR__ . '/setting.php';
    
    $conf = new RdKafka\Conf();
    $conf->set('api.version.request', 'true');
    $conf->set('message.send.max.retries', 5);
    $rk = new RdKafka\Producer($conf);
    ## If want to debug, set log level to LOG_DEBUG
    $rk->setLogLevel(LOG_INFO);
    $rk->addBrokers($setting['bootstrap_servers']);
    $topic = $rk->newTopic($setting['topic_name']);
    $a = $topic->produce(RD_KAFKA_PARTITION_UA, 0, "Message hello kafka");
    $rk->poll(0);
    while ($rk->getOutQLen() > 0) {
        $rk->poll(50);
    }
    echo "send succ" . PHP_EOL;
  2. Run the following command to send messages:
    php kafka-producer.php

Subscribe to messages

  1. Create a subscription program kafka-consumer.php.
    <? php
    $setting = require __DIR__ . '/setting.php';
    $conf = new RdKafka\Conf();
    $conf->set('api.version.request', 'true');
    
    $conf->set('group.id', $setting['consumer_id']);
    
    $conf->set('metadata.broker.list', $setting['bootstrap_servers']);
    
    $topicConf = new RdKafka\TopicConf();
    
    $conf->setDefaultTopicConf($topicConf);
    
    $consumer = new RdKafka\KafkaConsumer($conf);
    
    $consumer->subscribe([$setting['topic_name']]);
    
    echo "Waiting for partition assignment... (make take some time when\n";
    echo "quickly re-joining the group after leaving it.)\n";
    
    while (true) {
        $message = $consumer->consume(30 * 1000);
        switch ($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;
        }
    }
    
    ? >
  2. Run the following command to consume messages:
    php kafka-consumer.php