Bagaimana untuk Mendapatkan Offset Kumpulan Pengguna di Golang Kafka 10 Menggunakan `sarama-cluster`?

<code class="go">import (
    "context"
    "log"
    "strings"

    "github.com/Shopify/sarama"
)

func main() {
    groupName := "testgrp"
    topic := "topic_name"
    offset, err := GetCGOffset(context.Background(), "localhost:9092", groupName, topic)
    if err != nil {
        log.Fatal(err)
    }
    log.Printf("Consumer group %s offset for topic %s is: %d", groupName, topic, offset)
}

type gcInfo struct {
    offset int64
}

func (g *gcInfo) Setup(sarama.ConsumerGroupSession) error {
    return nil
}

func (g *gcInfo) Cleanup(sarama.ConsumerGroupSession) error {
    return nil
}

func (g *gcInfo) ConsumeClaim(_ sarama.ConsumerGroupSession, claim sarama.ConsumerGroupClaim) error {
    g.offset = claim.InitialOffset()
    return nil
}

func GetCGOffset(ctx context.Context, brokers, groupName, topic string) (int64, error) {
    config := sarama.NewConfig()
    config.Consumer.Offsets.AutoCommit.Enable = false // we're not going to update the consumer group offsets
    client, err := sarama.NewConsumerGroup(strings.Split(brokers, ","), groupName, config)
    if err != nil {
        return 0, err
    }
    info := gcInfo{}
    if err := client.Consume(ctx, []string{topic}, &info); err != nil {
        return 0, err
    }
    return info.offset, nil
}</code>