Alpakka Consumer 不使用通过 Docker compose 运行的来自 Kafka 的消息

Question

我已经通过 Docker compose 运行了 Kafka 和 Zookeeper。我可以使用 Kafka 终端向主题发送/使用消息，并且可以通过 Conduktor 监控所有内容。但不幸的是，我无法使用 Alpakka 连接器通过我的 Scala 应用程序使用 msgs。该应用程序连接到该主题，但是每当我向该主题发送一条消息时，什么都没有发生。

只有 Kafka 和 Zookeeper 正在通过 docker-compose 运行。我直接在主机上运行 Scala 消费者应用程序。

Docker 编写

version: '3'
services:
  zookeeper:
    image: wurstmeister/zookeeper
    ports:
      - "2181:2181"
  kafka:
    image: wurstmeister/kafka
    ports:
      - "9092:9092"
    environment:
      KAFKA_BROKER_ID: 1
      HOSTNAME_COMMAND: "route -n | awk '/UG[ \t]/{print $$2}'"
      KAFKA_ZOOKEEPER_CONNECT: zookeeper:2181
    depends_on:
      - zookeeper

Scala 应用

object Main extends App {
  implicit val actorSystem = ActorSystem()

  import actorSystem.dispatcher

  val kafkaConsumerSettings = ConsumerSettings(actorSystem, new StringDeserializer, new StringDeserializer)
    .withGroupId("new_id")
    .withCommitRefreshInterval(1.seconds)
    .withProperty(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest")
    .withBootstrapServers("localhost:9092")

  Consumer
    .plainSource(kafkaConsumerSettings, Subscriptions.topics("test1"))
    .map(msg => msg.value())
    .runWith(Sink.foreach(println)).onComplete {
    case Failure(exception) => exception.printStackTrace()
    case Success(value) => println("done")
  }
}

应用 - 控制台输出

16:58:33.877 INFO  [akka.event.slf4j.Slf4jLogger]                     Slf4jLogger started
16:58:34.470 INFO  [akka.kafka.internal.SingleSourceLogic]            [1955f] Starting. StageActor Actor[akka://default/system/Materializers/StreamSupervisor-0/$$a#-591284224]
16:58:34.516 INFO  [org.apache.kafka.clients.consumer.ConsumerConfig] ConsumerConfig values: 
    allow.auto.create.topics = true
    auto.commit.interval.ms = 5000
    auto.offset.reset = earliest
    bootstrap.servers = [localhost:9092]
    check.crcs = true
    client.dns.lookup = default
    client.id = 
    client.rack = 
    connections.max.idle.ms = 540000
    default.api.timeout.ms = 60000
    enable.auto.commit = false
    exclude.internal.topics = true
    fetch.max.bytes = 52428800
    fetch.max.wait.ms = 500
    fetch.min.bytes = 1
    group.id = novo_id
    group.instance.id = null
    heartbeat.interval.ms = 3000
    interceptor.classes = []
    internal.leave.group.on.close = true
    isolation.level = read_uncommitted
    key.deserializer = class org.apache.kafka.common.serialization.StringDeserializer
    max.partition.fetch.bytes = 1048576
    max.poll.interval.ms = 300000
    max.poll.records = 500
    metadata.max.age.ms = 300000
    metric.reporters = []
    metrics.num.samples = 2
    metrics.recording.level = INFO
    metrics.sample.window.ms = 30000
    partition.assignment.strategy = [class org.apache.kafka.clients.consumer.RangeAssignor]
    receive.buffer.bytes = 65536
    reconnect.backoff.max.ms = 1000
    reconnect.backoff.ms = 50
    request.timeout.ms = 30000
    retry.backoff.ms = 100
    sasl.client.callback.handler.class = null
    sasl.jaas.config = null
    sasl.kerberos.kinit.cmd = /usr/bin/kinit
    sasl.kerberos.min.time.before.relogin = 60000
    sasl.kerberos.service.name = null
    sasl.kerberos.ticket.renew.jitter = 0.05
    sasl.kerberos.ticket.renew.window.factor = 0.8
    sasl.login.callback.handler.class = null
    sasl.login.class = null
    sasl.login.refresh.buffer.seconds = 300
    sasl.login.refresh.min.period.seconds = 60
    sasl.login.refresh.window.factor = 0.8
    sasl.login.refresh.window.jitter = 0.05
    sasl.mechanism = GSSAPI
    security.protocol = PLAINTEXT
    security.providers = null
    send.buffer.bytes = 131072
    session.timeout.ms = 10000
    ssl.cipher.suites = null
    ssl.enabled.protocols = [TLSv1.2, TLSv1.1, TLSv1]
    ssl.endpoint.identification.algorithm = https
    ssl.key.password = null
    ssl.keymanager.algorithm = SunX509
    ssl.keystore.location = null
    ssl.keystore.password = null
    ssl.keystore.type = JKS
    ssl.protocol = TLS
    ssl.provider = null
    ssl.secure.random.implementation = null
    ssl.trustmanager.algorithm = PKIX
    ssl.truststore.location = null
    ssl.truststore.password = null
    ssl.truststore.type = JKS
    value.deserializer = class org.apache.kafka.common.serialization.StringDeserializer

16:58:34.701 INFO  [org.apache.kafka.common.utils.AppInfoParser]      Kafka version: 2.4.0
16:58:34.702 INFO  [org.apache.kafka.common.utils.AppInfoParser]      Kafka commitId: 77a89fcf8d7fa018
16:58:34.702 INFO  [org.apache.kafka.common.utils.AppInfoParser]      Kafka startTimeMs: 1585256314699
16:58:34.715 INFO  [org.apache.kafka.clients.consumer.KafkaConsumer]  [Consumer clientId=consumer-novo_id-1, groupId=novo_id] Subscribed to topic(s): test1
16:58:35.308 INFO  [org.apache.kafka.clients.Metadata]                [Consumer clientId=consumer-novo_id-1, groupId=novo_id] Cluster ID: c2XBuDIJTI-gBs9guTvG

Answer 1

导出KAFKA_ADVERTISED_LISTENERS

描述广播的主机名如何通过 客户。该值会发布到 ZooKeeper 以供客户端使用。

如果使用SSL 或SASL 协议，端点值必须指定 以下格式的协议：

• SSL：SSL:// 或 SASL_SSL://

• SASL：SASL_PLAINTEXT:// 或 SASL_SSL://

KAFKA_ADVERTISED_LISTENERS=PLAINTEXT://localhost:29092

---

现在你的消费者可以使用端口29092：

.withBootstrapServers("localhost:29092")