General Guidance for using kafka, and similar packages with frankenphp

Hi,

I am new to frankenphp, trying to evaluate this for a project. I started with https://github.com/f00b4r/2023-10-frankenphp and got it working. Now, I want to use some extensions like kafka, redis, mysql, etc. I used the following modifications to

1. Dockerfile

# Install PHP extensions rdkafka
RUN install-php-extensions rdkafka

2. Docker-compose.yml

services:
  app:
    image: frankapp
    build: .
    ports:
      - 80:80
    environment:
      - CADDY_DEBUG=debug
      - DEBUG=debug
      - FRANKENPHP_CONFIG=worker /srv/public/worker.php
      - SERVER_NAME=:80
    volumes:
      - ./:/srv
      - ./Caddyfile:/etc/caddy/Caddyfile
  kafka1:
    image: 'bitnami/kafka:3.7.0'
    container_name: kafka-3.7-controller-1
    ports:
      - 9093
    environment:
      # KRaft settings. No longer using zookeeper method.
      - KAFKA_CFG_NODE_ID=1
      - KAFKA_KRAFT_CLUSTER_ID=ZmNDEyNT
      - KAFKA_CFG_PROCESS_ROLES=controller
      - KAFKA_CFG_CONTROLLER_QUORUM_VOTERS=1@kafka1:9093
      # Listeners
      - KAFKA_CFG_LISTENERS=CONTROLLER://kafka1:9093
      - KAFKA_CFG_CONTROLLER_LISTENER_NAMES=CONTROLLER
  kafka4:
    image: 'bitnami/kafka:3.7.0'
    container_name: kafka-3.7-broker-4
    ports:
      - 9092
    environment:
      # KRaft settings. No longer using zookeeper method.
      - KAFKA_CFG_NODE_ID=4
      - KAFKA_KRAFT_CLUSTER_ID=ZmNDEyNT
      - KAFKA_CFG_PROCESS_ROLES=broker
      - KAFKA_CFG_CONTROLLER_QUORUM_VOTERS=1@kafka1:9093
      - KAFKA_CFG_AUTO_CREATE_TOPICS_ENABLE=true
      # Listeners
      - KAFKA_CFG_LISTENERS=PLAINTEXT://kafka4:9092
      - KAFKA_CFG_INTER_BROKER_LISTENER_NAME=PLAINTEXT
      - KAFKA_CFG_ADVERTISED_LISTENERS=PLAINTEXT://kafka4:9092
      - KAFKA_CFG_CONTROLLER_LISTENER_NAMES=CONTROLLER
      - KAFKA_CFG_LISTENER_SECURITY_PROTOCOL_MAP=CONTROLLER:PLAINTEXT,PLAINTEXT:PLAINTEXT,SSL:SSL,SASL_PLAINTEXT:SASL_PLAINTEXT,SASL_SSL:SASL_SSL

3. /public/worker.php

<?php declare(strict_types = 1);
ignore_user_abort(true);
do {
	$running = frankenphp_handle_request(function () {
		echo "Hello FrankenPHP!!";
		//print_r($_GET);  // for all GET variables
		//phpinfo();
		if(isset($_POST['testData'])){		
			$payload=trim($_POST['testData']);	
			$conf = new RdKafka\Conf();
			$conf->set('metadata.broker.list', 'kafka4:9092');
			
			$conf->set('socket.timeout.ms', 60); 
			$conf->set('request.timeout.ms', 60); 
			
			if (function_exists('pcntl_sigprocmask')) {
				pcntl_sigprocmask(SIG_BLOCK, array(SIGIO));
				$conf->set('internal.termination.signal', SIGIO);
			} else {
				$conf->set('queue.buffering.max.ms', 1);
			}
			
			$producer = new RdKafka\Producer($conf);
			$topic="testData";
			$kafkaTopic = $producer->newTopic($topic);
			$kafkaTopic->produce(RD_KAFKA_PARTITION_UA, 0, $payload);
			$producer->poll(0);
			for ($flushRetries = 0; $flushRetries < 10; $flushRetries++) {
				$result = $producer->flush(10000);
				if (RD_KAFKA_RESP_ERR_NO_ERROR === $result) {
					echo "Message Published";
					break;
				}
			}
			
		}
	});

	gc_collect_cycles();
} while ($running);

However, If I do a test on worker.php, I am getting the following error.

INFO[0001] Response body: Hello FrankenPHP!<br />
<b>Fatal error</b>:  Uncaught TypeError: RdKafka\Conf::set(): Argument #2 ($value) must be of type string, int given in /srv/public/worker.php:14
Stack trace:
#0 /srv/public/worker.php(14): RdKafka\Conf-&gt;set('socket.timeout....', 60)
#1 [internal function]: {closure}()
#2 /srv/public/worker.php(4): frankenphp_handle_request(Object(Closure))
#3 {main}
  thrown in <b>/srv/public/worker.php</b> on line <b>14</b><br />  source=console

I have another script, producer.php in the same folder, with the same publish code, and If I send a post request, it successfully publishes to kafka. So, it looks like the worker part is having the issue? I looked around for all available resources, including ai help, but their recommendations have not resolved this. Any help is much appreciated.

Start with /public/worker.php: compare its RdKafka configuration calls with the working producer.php, especially the values passed to Conf::set(). Review the Dockerfile and docker-compose.yml to confirm the rdkafka extension and Kafka service setup. Done means the worker handles the request and publishes the testData payload without the reported TypeError.