将 cloudevents 格式的数据发送到 Kafka 主题

Question

现在我有了这段代码，它工作正常。（它向 Kafka 主题发送一些 json 格式的数据）

j, err := json.Marshal(data)
if err != nil {
    log.Fatal(err)
}
msg := &sarama.ProducerMessage{
    Topic: tName,
    Value: sarama.StringEncoder(j),
}

_, _, err = producer.SendMessage(msg)

但有人希望拥有 cloudevents 格式的数据。 -> https://github.com/cloudevents/sdk-go 所以我该怎么办，因为这个事件结构不能直接转换为字符串。

type Event struct {
    Context     EventContext
    DataEncoded []byte
    // DataBase64 indicates if the event, when serialized, represents
    // the data field using the base64 encoding.
    // In v0.3, this field is superseded by DataContentEncoding
    DataBase64  bool
    FieldErrors map[string]error
}

所以这段代码甚至无法编译。

j, err := json.Marshal(data)
if err != nil {
    log.Fatal(err)
}

//...

event := cloudevents.NewEvent()
event.SetSource("example/uri") 
event.SetType("example.type")
event.SetData(cloudevents.ApplicationJSON, j)

producerMsg := &sarama.ProducerMessage{
    Topic: s.outputTopic,
    Value: sarama.StringEncoder(event),
}
_, _, err = s.producer.SendMessage(producerMsg)

我应该怎么做才能将此事件发送到 Kafka？尝试将 event.DataEncoded 转换为字符串或类似的东西？顺便提一句。编程语言是golang。

Answer 1

您是否看到文档中对事件进行序列化的部分？

https://github.com/cloudevents/sdk-go#serializedeserialize-a-cloudevent

event := cloudevents.NewEvent()
event.SetSource("example/uri") 
event.SetType("example.type") 
// data here is a map[string] interface{}, or some other Struct type representing the "example.type" schema type above 
event.SetData(cloudevents.ApplicationJSON, data)

bytes, err := json.Marshal(event)
if err != nil {
  log.Fatal(err)
}
producerMsg := &sarama.ProducerMessage{
    Topic: s.outputTopic,
    Value: bytes,  // you've already encoded the event 
}

否则，请务必查看提供的使用 CloudEvent 客户端的示例代码https://github.com/cloudevents/sdk-go/blob/main/samples/kafka/sender/main.go

sender, err := kafka_sarama.NewSender([]string{"127.0.0.1:9092"}, saramaConfig, "test-topic")
if err != nil {
    log.Fatalf("failed to create protocol: %s", err.Error())
}

defer sender.Close(context.Background())

c, err := cloudevents.NewClient(sender, cloudevents.WithTimeNow(), cloudevents.WithUUIDs())
if err != nil {
    log.Fatalf("failed to create client, %v", err)
}

event := cloudevents.NewEvent() 
event.Set... 

c.Send(..., event)

...

将 cloudevents 格式的数据发送到 Kafka 主题

Send data in cloudevents format to Kafka topic

go

apache-kafka

cloudevents