What are Go and message queues (NATS, RabbitMQ)?

Question

Accepted Answer

Go works with **message queues** via client libraries.

```go
// NATS: high-performance queue
import "github.com/nats-io/nats.go"

// Connect
nc, err := nats.Connect("nats://localhost:4222")
if err != nil {
    log.Fatal(err)
}
def nc.Close()

// Publish
nc.Publish("orders.new", []byte(`{"id": 1, "amount": 100}`))

// Subscribe
nc.Subscribe("orders.new", func(msg *nats.Msg) {
    fmt.Printf("Received: %s
", string(msg.Data))
})

// Request/Response
reply, err := nc.Request("orders.get", []byte(`{"id": 1}`), 5*time.Second)
fmt.Println(string(reply.Data))

// JetStream: persistent queue
js, _ := nc.JetStream()
js.Publish("orders.new", data)

// RabbitMQ
import amqp "github.com/rabbitmq/amqp091-go"

conn, _ := amqp.Dial("amqp://guest:guest@localhost:5672/")
ch, _ := conn.Channel()

// Queue declaration
q, _ := ch.QueueDeclare("orders", true, false, false, false, nil)

// Publish
ch.Publish("", q.Name, false, false, amqp.Publishing{
    ContentType: "application/json",
    Body:        []byte(`{"id": 1}`),
})

// Consume
msgs, _ := ch.Consume(q.Name, "", false, false, false, false, nil)
for msg := range msgs {
    fmt.Printf("Received: %s
", msg.Body)
    msg.Ack(false)
}
```

**NATS vs RabbitMQ:**
- NATS: fast, lightweight, pub/sub.
- RabbitMQ: reliable, routing, ack.

Go: What are Go and message queues (NATS, RabbitMQ)?