【kafka学习笔记】Go接入kafka

需要借助的库

github.com/Shopify/sarama // kafka主要的库*
github.com/bsm/sarama-cluster // kafka消费组

生产者

package producer

import (
    "fmt"
    "github.com/HappyTeemo7569/teemoKit/tlog"
    "github.com/Shopify/sarama"
    "kafkaDemo/define"
)

var (
    ProducerId = 1
)

type Producer struct {
    Producer   sarama.SyncProducer
    Topic      string //主题
    ProducerID int    //生产者Id
    MessageId  int
}

func (p *Producer) InitProducer() {
    config := sarama.NewConfig()
    config.Producer.RequiredAcks = sarama.WaitForAll          // 发送完数据需要leader和follow都确认
    config.Producer.Partitioner = sarama.NewRandomPartitioner // 新选出一个partition
    config.Producer.Return.Successes = true                   // 成功交付的消息将在success channel返回

    // 连接kafka
    client, err := sarama.NewSyncProducer([]string{define.SERVER_LIST}, config)
    if err != nil {
        tlog.Error("producer closed, err:", err)
        return
    }

    p.Producer = client
    p.Topic = define.TOPIC
    p.ProducerID = ProducerId
    p.MessageId = 1

    ProducerId++
}

func (p *Producer) SendMessage() {
    // 构造一个消息
    msg := &sarama.ProducerMessage{}
    msg.Topic = p.Topic
    txt := fmt.Sprintf("ProducerID:%d  this is a test log %d",
        p.ProducerID, p.MessageId)
    msg.Value = sarama.StringEncoder(txt)

    // 发送消息
    pid, offset, err := p.Producer.SendMessage(msg)
    //_, _, err := client.SendMessage(msg)
    if err != nil {
        fmt.Println("send msg failed, err:", err)
        return
    }
    tlog.Info(fmt.Sprintf("ProducerID:%d pid:%v offset:%v msg:%s",
        p.ProducerID, pid, offset, txt))

    p.MessageId++
}

func (p *Producer) Close() {
    p.Producer.Close()
}

消费者

package consumer

import (
    "github.com/HappyTeemo7569/teemoKit/tlog"
    "github.com/Shopify/sarama"
    "kafkaDemo/define"
)

type Consumer struct {
    Consumer   sarama.Consumer
    Topic      string
    ConsumerId int //消费者Id
}

func (c *Consumer) InitConsumer() error {
    consumer, err := sarama.NewConsumer([]string{define.SERVER_LIST}, nil)
    if err != nil {
        return err
    }
    c.Consumer = consumer
    c.Topic = define.TOPIC
    c.ConsumerId = ConsumerId
    ConsumerId++
    return nil
}

//指定partition
//offset 可以指定，传-1为获取最新offest
func (c *Consumer) GetMessage(partitionId int32, offset int64) {
    if offset == -1 {
        offset = sarama.OffsetNewest
    }
    pc, err := c.Consumer.ConsumePartition(c.Topic, partitionId, offset)
    if err != nil {
        tlog.Error("failed to start consumer for partition %d,err:%v", partitionId, err)
        //That topic/partition is already being consumed
        return
    }

    // 异步从每个分区消费信息
    go func(sarama.PartitionConsumer) {
        for msg := range pc.Messages() {
            tlog.Info("ConsumerId:%d Partition:%d Offset:%d Key:%v Value:%v", c.ConsumerId, msg.Partition, msg.Offset, msg.Key, string(msg.Value))
        }
    }(pc)
}

//遍历所有分区
func (c *Consumer) GetMessageToAll(offset int64) {
    partitionList, err := c.Consumer.Partitions(c.Topic) // 根据topic取到所有的分区
    if err != nil {
        tlog.Error("fail to get list of partition:err%v", err)
        return
    }
    tlog.Info("所有partition:", partitionList)

    for partition := range partitionList { // 遍历所有的分区
        c.GetMessage(int32(partition), offset)
    }
}

主函数

func main() {
    tlog.Info("开始")

    go producer.Put()
    go consumer.Get()

    for {
        time.Sleep(time.Hour * 60)
    }
}


func Put() {
    producer := new(Producer)
    producer.InitProducer()
    go func() {
        for {
            producer.SendMessage()
            time.Sleep(1 * time.Second)
        }
    }()
}

func Get() {

    offest := int64(0)

    consumer := new(Consumer)
    err := consumer.InitConsumer()
    if err != nil {
        tlog.Error("fail to init consumer, err:%v", err)
        return
    }
    consumer.GetMessageToAll(offest)
}

具体源码可以查看：
https://github.com/HappyTeemo7569/kafkaDemo