spark记录（19）SparkStreaming之从kafkaBroker和zookeeper获取offset，和使用zookeeper管理offset

一、从kafkaBroker获取offset

/**
 * 测试之前需要启动kafka
 * @author root
 *
 */
public class GetTopicOffsetFromKafkaBroker {
    public static void main(String[] args) {
        
        Map<TopicAndPartition, Long> topicOffsets = getTopicOffsets("node1:9092,node2:9092,node3:9092", "mytopic");
        Set<Entry<TopicAndPartition, Long>> entrySet = topicOffsets.entrySet();
        for(Entry<TopicAndPartition, Long> entry : entrySet) {
            TopicAndPartition topicAndPartition = entry.getKey();
            Long offset = entry.getValue();
            String topic = topicAndPartition.topic();
            int partition = topicAndPartition.partition();
            System.out.println("topic = "+topic+",partition = "+partition+",offset = "+offset);
        }
    
    }
    
    /**
     * 从kafka集群中得到当前topic，生产者在每个分区中生产消息的偏移量位置
     * @param KafkaBrokerServer
     * @param topic
     * @return
     */
    public static Map<TopicAndPartition,Long> getTopicOffsets(String KafkaBrokerServer, String topic){
        Map<TopicAndPartition,Long> retVals = new HashMap<TopicAndPartition,Long>();
        
        for(String broker:KafkaBrokerServer.split(",")){
            
            SimpleConsumer simpleConsumer = new SimpleConsumer(broker.split(":")[0],Integer.valueOf(broker.split(":")[1]), 64*10000,1024,"consumer"); 
            TopicMetadataRequest topicMetadataRequest = new TopicMetadataRequest(Arrays.asList(topic));
            TopicMetadataResponse topicMetadataResponse = simpleConsumer.send(topicMetadataRequest);
            
            for (TopicMetadata metadata : topicMetadataResponse.topicsMetadata()) {
                for (PartitionMetadata part : metadata.partitionsMetadata()) {
                    Broker leader = part.leader();
                    if (leader != null) { 
                        TopicAndPartition topicAndPartition = new TopicAndPartition(topic, part.partitionId()); 
                        
                        PartitionOffsetRequestInfo partitionOffsetRequestInfo = new PartitionOffsetRequestInfo(kafka.api.OffsetRequest.LatestTime(), 10000); 
                        OffsetRequest offsetRequest = new OffsetRequest(ImmutableMap.of(topicAndPartition, partitionOffsetRequestInfo), kafka.api.OffsetRequest.CurrentVersion(), simpleConsumer.clientId()); 
                        OffsetResponse offsetResponse = simpleConsumer.getOffsetsBefore(offsetRequest); 
                        
                        if (!offsetResponse.hasError()) { 
                            long[] offsets = offsetResponse.offsets(topic, part.partitionId()); 
                            retVals.put(topicAndPartition, offsets[0]);
                        }
                    }
                }
            }
            simpleConsumer.close();
        }
        return retVals;
    }
}

二、从zookeeper获取offset

public class GetTopicOffsetFromZookeeper {
    
    public static Map<TopicAndPartition,Long> getConsumerOffsets(String zkServers,String groupID, String topic) { 
        Map<TopicAndPartition,Long> retVals = new HashMap<TopicAndPartition,Long>();
        
        ObjectMapper objectMapper = new ObjectMapper();
        CuratorFramework  curatorFramework = CuratorFrameworkFactory.builder()
                .connectString(zkServers).connectionTimeoutMs(1000)
                .sessionTimeoutMs(10000).retryPolicy(new RetryUntilElapsed(1000, 1000)).build();
        
        curatorFramework.start();
        
        try{
            String nodePath = "/consumers/"+groupID+"/offsets/" + topic;
            if(curatorFramework.checkExists().forPath(nodePath)!=null){
                List<String> partitions=curatorFramework.getChildren().forPath(nodePath);
                for(String partiton:partitions){
                    int partitionL=Integer.valueOf(partiton);
                    Long offset=objectMapper.readValue(curatorFramework.getData().forPath(nodePath+"/"+partiton),Long.class);
                    TopicAndPartition topicAndPartition=new TopicAndPartition(topic,partitionL);
                    retVals.put(topicAndPartition, offset);
                }
            }
        }catch(Exception e){
            e.printStackTrace();
        }
        curatorFramework.close();
        
        return retVals;
    } 
    
    
    public static void main(String[] args) {
        Map<TopicAndPartition, Long> consumerOffsets = getConsumerOffsets("node3:2181,node4:2181,node5:2181","zhy","mytopic");
        Set<Entry<TopicAndPartition, Long>> entrySet = consumerOffsets.entrySet();
        for(Entry<TopicAndPartition, Long> entry : entrySet) {
            TopicAndPartition topicAndPartition = entry.getKey();
            String topic = topicAndPartition.topic();
            int partition = topicAndPartition.partition();
            Long offset = entry.getValue();
            System.out.println("topic = "+topic+",partition = "+partition+",offset = "+offset);
        }
    }
}

三、使用zookeeper管理offset

public class UseZookeeperManageOffset {
    /**
     * 使用log4j打印日志，“UseZookeeper.class” 设置日志的产生类
     */
    static final Logger logger = Logger.getLogger(UseZookeeperManageOffset.class);
    
    
    public static void main(String[] args) {
        /**
         * 加载log4j的配置文件，方便打印日志
         */
        ProjectUtil.LoadLogConfig();
        logger.info("project is starting...");
        
        /**
         * 从kafka集群中得到topic每个分区中生产消息的最大偏移量位置
         */
        Map<TopicAndPartition, Long> topicOffsets = GetTopicOffsetFromKafkaBroker.getTopicOffsets("node1:9092,node2:9092,node3:9092", "mytopic");
        
        /**
         * 从zookeeper中获取当前topic每个分区 consumer 消费的offset位置
         */
        Map<TopicAndPartition, Long> consumerOffsets = 
                GetTopicOffsetFromZookeeper.getConsumerOffsets("node3:2181,node4:2181,node5:2181","zhy","mytopic");
        
        /**
         * 合并以上得到的两个offset ，
         *     思路是：
         *         如果zookeeper中读取到consumer的消费者偏移量，那么就zookeeper中当前的offset为准。
         *         否则，如果在zookeeper中读取不到当前消费者组消费当前topic的offset，就是当前消费者组第一次消费当前的topic，
         *             offset设置为topic中消息的最大位置。
         */
        if(null!=consumerOffsets && consumerOffsets.size()>0){
            topicOffsets.putAll(consumerOffsets);
        }
        /**
         * 如果将下面的代码解开，是将topicOffset 中当前topic对应的每个partition中消费的消息设置为0，就是从头开始。
         */
//        for(Map.Entry<TopicAndPartition, Long> item:topicOffsets.entrySet()){
//          item.setValue(0l);
//        }
        
        /**
         * 构建SparkStreaming程序，从当前的offset消费消息
         */
        JavaStreamingContext jsc = SparkStreamingDirect.getStreamingContext(topicOffsets,"zhy");
        jsc.start();
        jsc.awaitTermination();
        jsc.close();
        
    }
}