package storm.kafka;
import backtype.storm.Config;
import backtype.storm.utils.Utils;
import com.netflix.curator.framework.CuratorFramework;
import com.netflix.curator.framework.CuratorFrameworkFactory;
import com.netflix.curator.retry.RetryNTimes;
import org.json.simple.JSONValue;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import storm.kafka.trident.GlobalPartitionInformation;
import java.io.UnsupportedEncodingException;
import java.util.List;
import java.util.Map;
public class DynamicBrokersReader {
public static final Logger LOG = LoggerFactory.getLogger(DynamicBrokersReader.class);
private CuratorFramework _curator;
private String _zkPath;
private String _topic;
public DynamicBrokersReader(Map conf, String zkStr, String zkPath, String topic) {
_zkPath = zkPath;
_topic = topic;
_curator = CuratorFrameworkFactory.newClient(
zkStr,
Utils.getInt(conf.get(Config.STORM_ZOOKEEPER_SESSION_TIMEOUT)),
15000,
new RetryNTimes(Utils.getInt(conf.get(Config.STORM_ZOOKEEPER_RETRY_TIMES)),
Utils.getInt(conf.get(Config.STORM_ZOOKEEPER_RETRY_INTERVAL))));
_curator.start();
}
/**
* Get all partitions with their current leaders
*/
public GlobalPartitionInformation getBrokerInfo() {
GlobalPartitionInformation globalPartitionInformation = new GlobalPartitionInformation();
try {
int numPartitionsForTopic = getNumPartitions();
String brokerInfoPath = brokerPath();
for (int partition = 0; partition < numPartitionsForTopic; partition++) {
int leader = getLeaderFor(partition);
String path = brokerInfoPath + "/" + leader;
try {
byte[] brokerData = _curator.getData().forPath(path);
Broker hp = getBrokerHost(brokerData);
globalPartitionInformation.addPartition(partition, hp);
} catch (org.apache.zookeeper.KeeperException.NoNodeException e) {
LOG.error("Node {} does not exist ", path);
}
}
} catch (Exception e) {
throw new RuntimeException(e);
}
LOG.info("Read partition info from zookeeper: " + globalPartitionInformation);
return globalPartitionInformation;
}
private int getNumPartitions() {
try {
String topicBrokersPath = partitionPath();
List<String> children = _curator.getChildren().forPath(topicBrokersPath);
return children.size();
} catch (Exception e) {
throw new RuntimeException(e);
}
}
public String partitionPath() {
return _zkPath + "/topics/" + _topic + "/partitions";
}
public String brokerPath() {
return _zkPath + "/ids";
}
/**
* get /brokers/topics/distributedTopic/partitions/1/state
* { "controller_epoch":4, "isr":[ 1, 0 ], "leader":1, "leader_epoch":1, "version":1 }
*
* @param partition
* @return
*/
private int getLeaderFor(long partition) {
try {
String topicBrokersPath = partitionPath();
byte[] hostPortData = _curator.getData().forPath(topicBrokersPath + "/" + partition + "/state");
Map<Object, Object> value = (Map<Object, Object>) JSONValue.parse(new String(hostPortData, "UTF-8"));
Integer leader = ((Number) value.get("leader")).intValue();
return leader;
} catch (Exception e) {
throw new RuntimeException(e);
}
}
public void close() {
_curator.close();
}
/**
* [zk: localhost:2181(CONNECTED) 56] get /brokers/ids/0
* { "host":"localhost", "jmx_port":9999, "port":9092, "version":1 }
*
* @param contents
* @return
*/
private Broker getBrokerHost(byte[] contents) {
try {
Map<Object, Object> value = (Map<Object, Object>) JSONValue.parse(new String(contents, "UTF-8"));
String host = (String) value.get("host");
Integer port = ((Long) value.get("port")).intValue();
return new Broker(host, port);
} catch (UnsupportedEncodingException e) {
throw new RuntimeException(e);
}
}
}