Message Queue Knowledge

Message Queue Knowledge Base

Quick reference for message broker operations and advanced messaging patterns. Focuses on broker-level operations — for event-driven patterns, see eda-knowledge.

Broker Comparison

Message Delivery Guarantees

Achieving At-Least-Once in PHP

// RabbitMQ: manual acknowledgment
$channel->basic_consume(
    queue: 'orders',
    no_ack: false,  // require explicit ack
    callback: function (AMQPMessage $msg) use ($channel): void {
        try {
            $this->handler->handle(json_decode($msg->getBody(), true));
            $channel->basic_ack($msg->getDeliveryTag());
        } catch (\Throwable $e) {
            $channel->basic_nack($msg->getDeliveryTag(), requeue: true);
        }
    },
);

Consumer Groups Overview

Ordering Guarantees

When to Use Which Broker

Detection Patterns

# RabbitMQ usage
Grep: "AMQPChannel|PhpAmqpLib|bunny|php-amqplib" --glob "**/*.php"
Grep: "RABBITMQ_|AMQP_" --glob "**/.env*"

# Kafka usage
Grep: "RdKafka|kafka|KafkaConsumer|KafkaProducer" --glob "**/*.php"
Grep: "KAFKA_" --glob "**/.env*"

# SQS usage
Grep: "SqsClient|aws/aws-sdk.*sqs" --glob "**/*.php"
Grep: "SQS_|AWS_SQS" --glob "**/.env*"

# Redis Streams
Grep: "XADD|XREAD|XREADGROUP|XACK" --glob "**/*.php"
Grep: "xAdd|xRead|xReadGroup" --glob "**/*.php"

# Consumer patterns
Grep: "basic_consume|consume\(|poll\(" --glob "**/*.php"
Grep: "basic_ack|basic_nack|commitAsync|xAck" --glob "**/*.php"

# Dead letter configuration
Grep: "dead.letter|x-dead-letter|DLQ|deadLetter" --glob "**/*.php"

References

For detailed information, load these reference files:

• references/rabbitmq-advanced.md — Queue types, exchange topologies, clustering, monitoring, PHP patterns
• references/kafka-advanced.md — Partitioning, consumer groups, schema registry, exactly-once, PHP patterns