I have a Kafka instance running (locally, in a Docker) and I created a producer in Go, using the sarama package.
As I want to use Kafka Streams on my topic, the producer has to embed a timestamp in the messages, or I get this ugly error message:
org.apache.kafka.streams.errors.StreamsException: Input record ConsumerRecord(topic = crawler_events, partition = 0, offset = 0, CreateTime = -1, serialized key size = -1, serialized value size = 187, headers = RecordHeaders(headers = [], isReadOnly = false), key = null, value = {XXX}) has invalid (negative) timestamp. Possibly because a pre-0.10 producer client was used to write this record to Kafka without embedding a timestamp, or because the input topic was created before upgrading the Kafka cluster to 0.10+. Use a different TimestampExtractor to process this data.
Here is the portion of code sending the message in my Go program:
// Init a connection to the Kafka host,
// create the producer,
// and count successes and errors in delivery
func (c *kafkaClient) init() {
config := sarama.NewConfig()
config.Producer.Return.Successes = true
c.config = *config
var err error
c.producer, err = sarama.NewAsyncProducer(c.hosts, &c.config)
if err != nil {
panic(err)
}
go func() {
for range c.producer.Successes() {
c.successes++
}
}()
go func() {
for range c.producer.Errors() {
c.errors++
}
}()
}
// Send a message to the Kafka topic, WITH TIMESTAMP
func (c *kafkaClient) send(event string) {
message := &sarama.ProducerMessage{
Topic: c.topic,
Value: sarama.StringEncoder(event),
Timestamp: time.Now(),
}
c.producer.Input() <- message
c.enqueued++
}
As you can see, the timestamp I try to send is time.Now()
.
When I run the console consumer to see the received timestamps:
docker-compose exec kafka /opt/kafka/bin/kafka-console-consumer.sh \
--bootstrap-server localhost:9092 --topic crawler_events \
--from-beginning --property print.timestamp=true
I see they are all "-1":
CreateTime:-1 {"XXX"}
When adding a message to the topic with the console producer, I have the expected timestamps like:
CreateTime:1539010180284 hello
What am I doing wrong? Thanks for your help.