我正在寻找java客户机(kafka consumer)来使用来自多个代理的消息。请给出建议
下面是使用simple partitioner将消息发布到多个代理的代码。
主题是用复制因子“2”和分区“3”创建的。
public int partition(String topic, Object key, byte[] keyBytes, Object value, byte[] valueBytes, Cluster cluster)
{
List<PartitionInfo> partitions = cluster.partitionsForTopic(topic);
int numPartitions = partitions.size();
logger.info("Number of Partitions " + numPartitions);
if (keyBytes == null)
{
int nextValue = counter.getAndIncrement();
List<PartitionInfo> availablePartitions = cluster.availablePartitionsForTopic(topic);
if (availablePartitions.size() > 0)
{
int part = toPositive(nextValue) % availablePartitions.size();
int selectedPartition = availablePartitions.get(part).partition();
logger.info("Selected partition is " + selectedPartition);
return selectedPartition;
}
else
{
// no partitions are available, give a non-available partition
return toPositive(nextValue) % numPartitions;
}
}
else
{
// hash the keyBytes to choose a partition
return toPositive(Utils.murmur2(keyBytes)) % numPartitions;
}
}
public void publishMessage(String message , String topic)
{
Producer<String, String> producer = null;
try
{
producer = new KafkaProducer<>(producerConfigs());
logger.info("Topic to publish the message --" + this.topic);
for(int i =0 ; i < 10 ; i++)
{
producer.send(new ProducerRecord<String, String>(this.topic, message));
logger.info("Message Published Successfully");
}
}
catch(Exception e)
{
logger.error("Exception Occured " + e.getMessage()) ;
}
finally
{
producer.close();
}
}
public Map<String, Object> producerConfigs()
{
loadPropertyFile();
Map<String, Object> propsMap = new HashMap<>();
propsMap.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, brokerList);
propsMap.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, StringSerializer.class);
propsMap.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, StringSerializer.class);
propsMap.put(ProducerConfig.PARTITIONER_CLASS_CONFIG, SimplePartitioner.class);
propsMap.put(ProducerConfig.ACKS_CONFIG, "1");
return propsMap;
}
public Map<String, Object> consumerConfigs() {
Map<String, Object> propsMap = new HashMap<>();
System.out.println("properties.getBootstrap()" + properties.getBootstrap());
propsMap.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, properties.getBootstrap());
propsMap.put(ConsumerConfig.ENABLE_AUTO_COMMIT_CONFIG, false);
propsMap.put(ConsumerConfig.AUTO_COMMIT_INTERVAL_MS_CONFIG, properties.getAutocommit());
propsMap.put(ConsumerConfig.SESSION_TIMEOUT_MS_CONFIG, properties.getTimeout());
propsMap.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class);
propsMap.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class);
propsMap.put(ConsumerConfig.GROUP_ID_CONFIG, properties.getGroupid());
propsMap.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, properties.getAutooffset());
return propsMap;
}
@KafkaListener(id = "ID1", topics = "${config.topic}", group = "${config.groupid}")
public void listen(ConsumerRecord<?, ?> record)
{
logger.info("Message Consumed " + record);
logger.info("Partition From which Record is Received " + record.partition());
this.message = record.value().toString();
}
bootstrap.servers=[localhost:9092, localhost:9093, localhost:9094]
2条答案
按热度按时间e0bqpujr1#
集群中kafka代理节点的数量与使用者逻辑无关。集群中的节点仅用于容错和引导过程。您将消息传递放置在基于某些自定义逻辑的不同主题分区中,这也不会影响使用者逻辑。即使只有一个使用者,该使用者也会使用来自主题订阅的所有分区的消息。我要求你检查你的Kafka集群与单代理节点代码。。。
ljo96ir52#
如果您使用常规java使用者,它将自动从多个代理读取数据。您不需要编写特殊代码。只需订阅您想要消费的主题,消费将自动连接到相应的代理。您只提供一个“单一入口点”代理——客户机自动计算出集群的所有其他代理。