Go operation kafka package sarama

Overview

sarama is a pure Go client library for working with Apache Kafka (version 0.8 and higher). It includes a high-level API to easily generate and consume messages, and a low-level API to control bytes on the wire when the high-level API is insufficient.
There are more stars on github (recommended).

• Open source package: https://github.com/Shopify/sarama
• Document address: https://pkg.go.dev/github.com/shopify/sarama

Less gossip, the above example

package main

import (
    "context"
    "fmt"
    "github.com/Shopify/sarama"
    "log"
    "os"
    "os/signal"
    "sync"
)

type consumerGroupHandler struct {
}

func (consumerGroupHandler) Setup(sarama.ConsumerGroupSession) error {
    return nil
}
func (consumerGroupHandler) Cleanup(sarama.ConsumerGroupSession) error { return nil }

// ConsumeClaim must start a consumer loop of ConsumerGroupClaim's Messages().
func (consumerGroupHandler) ConsumeClaim(session sarama.ConsumerGroupSession, claim sarama.ConsumerGroupClaim) error {
    for msg := range claim.Messages() {
        log.Printf("Message claimed: value = %s, timestamp = %v, topic = %s", msg.Value, msg.Timestamp, msg.Topic)
        session.MarkMessage(msg, "")
    }
    return nil
}

//消费者组
func SaramaConsumerGroup() {
    config := sarama.NewConfig()
    config.Consumer.Return.Errors = false
    config.Version = sarama.V0_10_2_0                     // specify appropriate version
    config.Consumer.Offsets.Initial = sarama.OffsetOldest // 未找到组消费位移的时候从哪边开始消费

    group, err := sarama.NewConsumerGroup([]string{"localhost:9092"}, "my-group", config)
    if err != nil {
        panic(err)
    }
    defer func() { _ = group.Close() }()

    // Track errors
    go func() {
        for err := range group.Errors() {
            fmt.Println("ERROR", err)
        }
    }()
    fmt.Println("Consumed start")
    // Iterate over consumer sessions.
    ctx := context.Background()
    for {
        topics := []string{"my_topic"}
        handler := consumerGroupHandler{}

        // `Consume` should be called inside an infinite loop, when a
        // server-side rebalance happens, the consumer session will need to be
        // recreated to get the new claims
        err := group.Consume(ctx, topics, handler)
        if err != nil {
            panic(err)
        }
    }
}

//消费者
func SaramaConsumer() {
    consumer, err := sarama.NewConsumer([]string{"localhost:9092"}, sarama.NewConfig())
    if err != nil {
        panic(err)
    }

    defer func() {
        if err := consumer.Close(); err != nil {
            log.Fatalln(err)
        }
    }()

    partitionConsumer, err := consumer.ConsumePartition("my_topic", 0, sarama.OffsetNewest)
    if err != nil {
        panic(err)
    }

    defer func() {
        if err := partitionConsumer.Close(); err != nil {
            log.Fatalln(err)
        }
    }()

    // Trap SIGINT to trigger a shutdown.
    signals := make(chan os.Signal, 1)
    signal.Notify(signals, os.Interrupt)

    consumed := 0
ConsumerLoop:
    for {
        select {
        case msg := <-partitionConsumer.Messages():
            log.Printf("Consumed message offset %d\n", msg.Offset)
            consumed++
        case <-signals:
            break ConsumerLoop
        }
    }

    log.Printf("Consumed: %d\n", consumed)
}

//异步生产者Goroutines
func SyncProducer() {
    config := sarama.NewConfig()
    config.Producer.Return.Successes = true
    config.Producer.Return.Errors = true
    producer, err := sarama.NewAsyncProducer([]string{"localhost:9092"}, config)
    if err != nil {
        panic(err)
    }

    // Trap SIGINT to trigger a graceful shutdown.
    signals := make(chan os.Signal, 1)
    signal.Notify(signals, os.Interrupt)

    var (
        wg                                  sync.WaitGroup
        enqueued, successes, producerErrors int
    )

    wg.Add(1)
    go func() {
        defer wg.Done()
        for range producer.Successes() {
            successes++
        }
    }()

    wg.Add(1)
    go func() {
        defer wg.Done()
        for err := range producer.Errors() {
            log.Println(err)
            producerErrors++
        }
    }()

ProducerLoop:
    for {
        message := &sarama.ProducerMessage{Topic: "my_topic", Value: sarama.StringEncoder("testing 456")}
        select {
        case producer.Input() <- message:
            enqueued++

        case <-signals:
            producer.AsyncClose() // Trigger a shutdown of the producer.
            break ProducerLoop
        }
    }

    wg.Wait()

    log.Printf("Successfully produced: %d; errors: %d\n", successes, producerErrors)
}

//异步生产者Select
func SyncProducerSelect() {
    producer, err := sarama.NewAsyncProducer([]string{"localhost:9092"}, nil)
    if err != nil {
        panic(err)
    }

    defer func() {
        if err := producer.Close(); err != nil {
            log.Fatalln(err)
        }
    }()

    // Trap SIGINT to trigger a shutdown.
    signals := make(chan os.Signal, 1)
    signal.Notify(signals, os.Interrupt)

    var enqueued, producerErrors int
ProducerLoop:
    for {
        select {
        case producer.Input() <- &sarama.ProducerMessage{Topic: "my_topic", Key: nil, Value: sarama.StringEncoder("testing 123")}:
            enqueued++
        case err := <-producer.Errors():
            log.Println("Failed to produce message", err)
            producerErrors++
        case <-signals:
            break ProducerLoop
        }
    }
    log.Printf("Enqueued: %d; errors: %d\n", enqueued, producerErrors)
}

//同步生产模式
func SaramaProducer() {
    producer, err := sarama.NewSyncProducer([]string{"localhost:9092"}, nil)
    if err != nil {
        log.Fatalln(err)
    }
    defer func() {
        if err := producer.Close(); err != nil {
            log.Fatalln(err)
        }
    }()

    msg := &sarama.ProducerMessage{Topic: "my_topic", Value: sarama.StringEncoder("testing 123")}
    partition, offset, err := producer.SendMessage(msg)
    if err != nil {
        log.Printf("FAILED to send message: %s\n", err)
    } else {
        log.Printf("> message sent to partition %d at offset %d\n", partition, offset)
    }

}

func main() {
    //生产者
    go SyncProducer()
    //go SaramaProducer()
    //go SyncProducerSelect()

    //消费者
    SaramaConsumerGroup()
    //SaramaConsumer()

}

links

https://pkg.go.dev/github.com/Shopify/sarama
https://github.com/Shopify/sarama

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