KafkaException：在 kafka.tools.ConsoleProducer$LineMessageReader.readMessage 的第 1 行找不到密钥

Question

简而言之，我启动了 Kafka，成功创建了一个主题，启动了一个启用了密钥的生产者。到目前为止，一切都很好。我发送了一条简单的消息，我收到了

root@kafka:/# kafka-console-producer --broker-list localhost:9092 --topic testkey --property "parse.key=true" propert
y "key.separator=:"
>1:fisrtmessage
org.apache.kafka.common.KafkaException: No key found on line 1: 1:fisrtmessage
        at kafka.tools.ConsoleProducer$LineMessageReader.readMessage(ConsoleProducer.scala:275)
        at kafka.tools.ConsoleProducer$.main(ConsoleProducer.scala:55)
        at kafka.tools.ConsoleProducer.main(ConsoleProducer.scala)
root@kafka:/#

这里既是生产者又是消费者。如您所见，消费者没有收到消息，生产者崩溃了。

docker-compose.yml

version: '3'

services:
  zookeeper:
    image: confluentinc/cp-zookeeper:5.4.0
    hostname: zookeeper
    container_name: zookeeper
    ports:
      - "2181:2181"
    environment:
      ZOOKEEPER_CLIENT_PORT: 2181
      ZOOKEEPER_TICK_TIME: 2000

  broker:
    image: confluentinc/cp-server:5.4.0
    hostname: broker
    container_name: broker
    depends_on:
      - zookeeper
    ports:
      - "9092:9092"
    environment:
      KAFKA_BROKER_ID: 1
      KAFKA_ZOOKEEPER_CONNECT: 'zookeeper:2181'
      KAFKA_LISTENER_SECURITY_PROTOCOL_MAP: PLAINTEXT:PLAINTEXT,PLAINTEXT_HOST:PLAINTEXT
      KAFKA_ADVERTISED_LISTENERS: PLAINTEXT://broker:29092,PLAINTEXT_HOST://localhost:9092
      KAFKA_METRIC_REPORTERS: io.confluent.metrics.reporter.ConfluentMetricsReporter
      KAFKA_OFFSETS_TOPIC_REPLICATION_FACTOR: 1
      KAFKA_GROUP_INITIAL_REBALANCE_DELAY_MS: 0
      KAFKA_CONFLUENT_LICENSE_TOPIC_REPLICATION_FACTOR: 1
      CONFLUENT_METRICS_REPORTER_BOOTSTRAP_SERVERS: broker:29092
      CONFLUENT_METRICS_REPORTER_ZOOKEEPER_CONNECT: zookeeper:2181
      CONFLUENT_METRICS_REPORTER_TOPIC_REPLICAS: 1
      CONFLUENT_METRICS_ENABLE: 'true'
      CONFLUENT_SUPPORT_CUSTOMER_ID: 'anonymous'

  kafka-tools:
    image: confluentinc/cp-kafka:5.4.0
    hostname: kafka
    container_name: kafka
    command: ["tail", "-f", "/dev/null"]
    network_mode: "host"

Answer 1

您对 kafka-console-producer 的调用在 property 的第二次调用中丢失 --。

这意味着 keySeparator 不是您提供的那个 (:)，而是退回到默认值。根据code的ConsoleProducer默认值是：

var keySeparator = "\t"

由于您提供的字符串不包含任何制表符，因此它会抛出异常“No key found on line ...”，这是在 line 代码处完成的。