What are message brokers? Which ones do you know? How does RabbitMQ differ from Kafka?

Message Brokers are systems that facilitate the transfer of messages between applications or services, allowing them to exchange data asynchronously and reliably.

Popular brokers:

• RabbitMQ
• Apache Kafka
• ActiveMQ
• Amazon SQS

Differences between RabbitMQ and Kafka:

• RabbitMQ is a classic message broker based on queues and message routing. It supports various protocols (AMQP), guarantees message delivery, and is suitable for complex scenarios with acknowledgments and routing.

• Kafka is a distributed data streaming platform focused on high throughput and storing large volumes of messages as logs. Kafka is more suitable for processing data streams and analytics.

Key differences:

Characteristic	RabbitMQ	Kafka
Model	Queues and exchanges	Log with partitions
Message storage	Short-term, until read	Long-term, with re-read capability
Delivery approach	Push (sending messages)	Pull (clients read messages themselves)
Usage	Complex routing, RPC	Stream processing, analytics

Example of using RabbitMQ in Go (with the amqp library):

conn, _ := amqp.Dial("amqp://guest:guest@localhost:5672/")
ch, _ := conn.Channel()
q, _ := ch.QueueDeclare("task_queue", true, false, false, false, nil)
body := "Hello World"
ch.Publish("", q.Name, false, false, amqp.Publishing{
  ContentType: "text/plain",
  Body:        []byte(body),
})

Kafka in Go is usually used through the sarama or confluent-kafka-go libraries for working with topics and partitions.