Kafka를 Golang과 연결

package main

import (
  "fmt"
  "github.com/confluentinc/confluent-kafka-go/kafka"
)

var (
  broker  = "localhost:9092"
  groupId = "group-id"
  topic   = "topic-name"
)

func startProducer() {
  p, err := kafka.NewProducer(&kafka.ConfigMap{"bootstrap.servers": broker})
  if err != nil {
    panic(err)
  }

  go func() {
    for e := range p.Events() {
      switch ev := e.(type) {
      case *kafka.Message:
        if ev.TopicPartition.Error != nil {
          fmt.Printf("Delivery failed: %v\n", ev.TopicPartition)
        } else {
          fmt.Printf("Delivered message to %v\n", ev.TopicPartition)
        }
      }
    }
  }()

  for _, word := range []string{"message 1", "message 2", "message 3"} {
    p.Produce(&kafka.Message{
      TopicPartition: kafka.TopicPartition{Topic: &topic, Partition: kafka.PartitionAny},
      Value:          []byte(word),
    }, nil)
  }
}

func startConsumer() {
  c, err := kafka.NewConsumer(&kafka.ConfigMap{
    "bootstrap.servers": broker,
    "group.id":          groupId,
    "auto.offset.reset": "earliest",
  })

  if err != nil {
    panic(err)
  }
  c.Subscribe(topic, nil)

  for {
    msg, err := c.ReadMessage(-1)
    if err == nil {
      fmt.Printf("Message on %s: %s\n", msg.TopicPartition, string(msg.Value))
    } else {
      fmt.Printf("Consumer error: %v (%v)\n", err, msg)
      break
    }
  }

  c.Close()
}

func main() {
  startProducer()
  startConsumer()
}