Question

我正在尝试使用库clj-kafka。

这是我的代码

  (use [clj-kafka.producer]
       [clj-kafka.zk]
       [clj-kafka.consumer.zk]
       [clj-kafka.core]))

(brokers {"zookeeper.connect" "localhost:2181"})

(def p (producer {"metadata.broker.list" "localhost:9092"
                  "serializer.class" "kafka.serializer.DefaultEncoder"
                  "partitioner.class" "kafka.producer.DefaultPartitioner"}))

(send-message p (message "test" (.getBytes "this is my message")))

(def config {"zookeeper.connect" "localhost:2181"
             "group.id" "clj-kafka.consumer"
             "auto.offset.reset" "smallest"
             "auto.commit.enable" "false"})

(with-resource [c (consumer config)]
  shutdown
  (take 2 (messages c "test"))) ;; return ()

我用

启动zookepper-server和kafka本身

bin/zookeeper-server-start.sh config/zookeeper.properties
bin/kafka-server-start.sh config/server.properties

config / zookepper.properties：

dataDir=/tmp/zookeeper
clientPort=2181
maxClientCnxns=0

和config / server.properties：

broker.id=0
listeners=PLAINTEXT://:9092
num.network.threads=3
num.io.threads=8
socket.send.buffer.bytes=102400
zocket.receive.buffer.bytes=102400
socket.request.max.bytes=104857600
log.dirs=/tmp/kafka-logs
num.partitions=1
num.recovery.threads.per.data.dir=1
log.retention.hours=168
log.segment.bytes=1073741824
log.retention.check.interval.ms=300000
zookeeper.connect=localhost:2181
zookeeper.connection.timeout.ms=6000

问题＆＃39;是我执行时：

(with-resource [c (consumer config)]
  shutdown
  (take 2 (messages c "test"))) ;; return empty ()

这里有什么想法吗？

提前致谢

Answer 1

请参阅此github issue。似乎文档不是很好。你必须用doall强制实现序列（懒惰）。试试这个：

(with-resource [c (consumer config)]
  shutdown
  (doall (take 2 (messages c "test"))))

clj-kafka - 消费者空

1 个答案: