package main
import (
   "fmt"
   "github.com/Shopify/sarama"
   cluster "github.com/bsm/sarama-cluster"
   "time"
)
var (
   Consumer *cluster.Consumer
   producer sarama.SyncProducer
   brokers = []string{"ip1:9092","ip2:9092","ip3:9092"}
   topic = "testGo"
   groupId = "testGo_test1"
)
func initProducer() {
   var err error
   config := sarama.NewConfig()
   config.Producer.RequiredAcks = sarama.WaitForLocal
   config.Producer.Retry.Max = 3
   config.Producer.Return.Successes = true
   brokers := brokers
   producer, err = sarama.NewSyncProducer(brokers,config)
   if err != nil {
      fmt.Printf("生產者初始化失敗 -> %v \n", err)
      panic(err)
   }
   fmt.Println("生產者初始化成功。")
}
func initConsumer()  {
   var err error
   config := cluster.NewConfig()
   config.Consumer.Group.Rebalance.Strategy = sarama.BalanceStrategyRange
   config.Consumer.Offsets.Initial = sarama.OffsetNewest
   Consumer, err = cluster.NewConsumer(brokers,groupId,[]string{topic},config)
   if err != nil {
      fmt.Printf("消費者初始化失敗 -> %v \n", err)
      panic(err.Error())
   }
   if Consumer == nil {
      panic(fmt.Sprintf("消費者為空. kafka info -> {brokers:%v, topic: %v, group: %v}", brokers, topic, groupId))
   }
   fmt.Printf("消費者初始化成功, consumer -> %v, topic -> %v, ", Consumer, topic)
}
func main() {
   initProducer()
   initConsumer()
   //生產消息
   for i := 1;i < 100; i ++ {
      pid, offset, err := producer.SendMessage(&sarama.ProducerMessage{
         Topic:     topic,
         Key:       sarama.StringEncoder(i),
         Value:     sarama.ByteEncoder("this is test message."),
      })
      if err != nil {
         fmt.Println("發送消息失敗, err:", err)
         return
      }
      fmt.Printf("offset: %v\n", offset)
   }
   time.Sleep(2 * time.Second)
   //消費消息
   for {
       select {
       case msg, ok := <-Consumer.Messages():
           if ok {
              fmt.Printf("kafka msg: %s \n", msg.Value)
           }
      }
   }
}