php-kafka-consumer

An Apache Kafka consumer in PHP. Subscribe to topics and define callbacks to handle the messages.

Requirements

In order to use this library, you'll need the php-rdkafka PECL extension. Please notice that the extension requires the librdkafka C library.

Minimum requirements:

Dependency	version
librdkafka	v1.5.3
PHP	7.4 +
ext-rdkafka	3.0 +
Laravel	6 +

Install

Using composer:

composer require arquivei/php-kafka-consumer

Usage

<?php

require_once 'vendor/autoload.php';

use Kafka\Consumer\ConsumerBuilder;
use Kafka\Consumer\Entities\Config\Sasl;

class DefaultConsumer
{
    public function __invoke(string $message): void
    {
        print 'Init: ' . date('Y-m-d H:i:s') . PHP_EOL;
        sleep(2);
        print 'Finish: ' . date('Y-m-d H:i:s') . PHP_EOL;
    }
}

$consumer = ConsumerBuilder::create('broker:port', 'php-kafka-consumer-group-id', ['topic'])
    ->withSasl(new Sasl('username', 'pasword', 'mechanisms'))
    ->withCommitBatchSize(1)
    ->withSecurityProtocol('security-protocol')
    ->withHandler(new DefaultConsumer()) // or any callable
    ->build();

$consumer->consume();

Or by using the legacy API:

<?php

require_once 'vendor/autoload.php';

use Kafka\Consumer\Contracts\Consumer;
use Kafka\Consumer\Entities\Config;
use Kafka\Consumer\Entities\Config\Sasl;

class DefaultConsumer extends Consumer
{
    public function handle(string $message): void
    {
        print 'Init: ' . date('Y-m-d H:i:s') . PHP_EOL;
        sleep(2);
        print 'Finish: ' . date('Y-m-d H:i:s') . PHP_EOL;
    }
}

$config = new Config(
    new Sasl(
        'username',
        'password',
        'mechanisms'
    ),
    ['topic'],
    'broker:port',
    1,
    'php-kafka-consumer-group-id',
    new DefaultConsumer(),
    'PLAINTEXT',
    'topic-dlq',
    1,
    6
);

$consumer = new \Kafka\Consumer\Consumer($config);
$consumer->consume();

Usage with Laravel

You need to add the php-kafka-consig.php in config path:

<?php

return [
    'topic' => 'topic',
    'broker' => 'broker',
    'groupId' => 'group-id',
    'securityProtocol' => 'security-protocol',
    'sasl' => [
        'mechanisms' => 'mechanisms',
        'username' => 'username',
        'password' => 'password',
    ],
];

Use the command to execute the consumer:

$ php artisan arquivei:php-kafka-consumer --consumer="App\Consumers\YourConsumer" --commit=1

Middlewares

Middlewares are simple callables that receive two arguments: the message being handled and the next handler. Some possible use cases for middlewares: message transformation, filtering, logging stuff, or even transaction handling, your imagination is the limit.

<?php

use Kafka\Consumer\ConsumerBuilder;

$consumer = ConsumerBuilder::create('broker:port', 'php-kafka-consumer-group-id', ['topic'])
    ->withHandler(function ($message) {/** ... */})
    // You may add any number of middlewares, they will be executed in the order provided
    ->withMiddleware(function (string $rawMessage, callable $next): void {
        $decoded = json_decode($rawMessage, true);
        $next($decoded);
    })
    ->withMiddleware(function (array $message, callable $next): void {
        if (! isset($message['foo'])) {
            return;
        }
        $next($message);
    })
    ->build();

$consumer->consume();

Build and test

If you want to contribute, there are a few utilities that will help.

First create a container:

docker-compose up -d --build

If you have make, you can use pre defined commands in the Makefile

make build

Then install the dependencies:

docker-compose exec php-fpm composer install

or with make:

make composer install

You can run tests locally:

docker-compose exec php-fpm ./vendor/phpunit/phpunit/phpunit tests

or with make:

make test

and check for coverage:

docker-compose exec php-fpm phpdbg -qrr ./vendor/bin/phpunit --whitelist src/ --coverage-html coverage/

or with make:

make coverage