func main() {
    conn, err := amqp.Dial("amqp://guest:guest@localhost:5672/")
    if err != nil {
        panic(err)
    }
    defer conn.Close()

    for _, q := range []string{"q1", "q2", "q3"} {
        go RunFetcher(q, conn, 3, 50)

    }

    select {}
}


func RunFetcher(queueName string, conn *amqp.Connection, workers, qos int) {
    ch, err := conn.Channel()
    if err != nil {
        log.Println(err.Error())
        return
    }

    ch.Qos(qos, 0, false)
    defer ch.Close()
    msgs, err := ch.Consume(queueName, "", false, false, false, false, nil)
    if err != nil {
        log.Println(err.Error())
        return
    }

    for index := 0; index < workers; index++ {
        go func() {
            for d := range msgs {
                // process message
                d.Ack(false)
            }
        }()
    }

    select {}
}