private SimpleConsumer findLeaderConsumer(int partition) {
try {
if (consumer != null) {
return consumer;
}
PartitionMetadata metadata = findLeader(partition);
if (metadata == null) {
leaderBroker = null;
consumer = null;
return null;
}
leaderBroker = metadata.leader();
consumer =
new SimpleConsumer(
leaderBroker.host(),
leaderBroker.port(),
config.socketTimeoutMs,
config.socketReceiveBufferBytes,
config.clientId);
return consumer;
} catch (Exception e) {
LOG.error(e.getMessage(), e);
}
return null;
}
public static void fetch() {
HashMap<String, HashMap<String, String>> brokerDetails = new HashMap<>();
List<kafka.javaapi.TopicMetadata> data = MetadataDump();
HashMap<String, String> topicDetails = new HashMap<>();
String topic;
for (kafka.javaapi.TopicMetadata item : data) {
topic = item.topic();
for (kafka.javaapi.PartitionMetadata part : item.partitionsMetadata()) {
String replicas = "";
String isr = "";
for (kafka.cluster.Broker replica : part.replicas()) {
replicas += " " + replica.host();
}
for (kafka.cluster.Broker replica : part.isr()) {
isr += " " + replica.host();
}
topicDetails.put("partition", String.valueOf(part.partitionId()));
topicDetails.put("leader", part.leader().host());
topicDetails.put("replicas", "[" + replicas + "]");
topicDetails.put("isr", "[" + isr + "]");
}
brokerDetails.put(topic, topicDetails);
}
current = brokerDetails;
}
private PartitionMetadata findLeader(
List<String> a_seedBrokers, int a_port, String a_topic, int a_partition) {
PartitionMetadata returnMetaData = null;
loop:
for (String seed : a_seedBrokers) {
SimpleConsumer consumer = null;
try {
consumer = new SimpleConsumer(seed, a_port, 100000, 64 * 1024, "leaderLookup");
List<String> topics = Collections.singletonList(a_topic);
TopicMetadataRequest req = new TopicMetadataRequest(topics);
kafka.javaapi.TopicMetadataResponse resp = consumer.send(req);
List<TopicMetadata> metaData = resp.topicsMetadata();
for (TopicMetadata item : metaData) {
for (PartitionMetadata part : item.partitionsMetadata()) {
if (part.partitionId() == a_partition) {
returnMetaData = part;
break loop;
}
}
}
} catch (Exception e) {
System.out.println(
"Error communicating with Broker ["
+ seed
+ "] to find Leader for ["
+ a_topic
+ ", "
+ a_partition
+ "] Reason: "
+ e);
} finally {
if (consumer != null) {
consumer.close();
}
}
}
if (returnMetaData != null) {
m_replicaBrokers.clear();
for (kafka.cluster.Broker replica : returnMetaData.replicas()) {
m_replicaBrokers.add(replica.host());
}
}
return returnMetaData;
}
public BlockingChannel create(ConsumerGroupId consumerGroupId) {
ConsumerMetadataResponse metadataResponse = readConsumerMetadata(consumerGroupId);
if (metadataResponse.errorCode() != ErrorMapping.NoError()) {
throw new ReadingConsumerMetadataException(metadataResponse.errorCode());
}
Broker coordinator = metadataResponse.coordinator();
BlockingChannel blockingChannel =
new BlockingChannel(
coordinator.host(),
coordinator.port(),
BlockingChannel.UseDefaultBufferSize(),
BlockingChannel.UseDefaultBufferSize(),
readTimeout);
return blockingChannel;
}
public ByteBufferMessageSet fetchMessages(int partition, long offset) throws IOException {
String topic = config.topic;
FetchRequest req =
new FetchRequestBuilder()
.clientId(config.clientId)
.addFetch(topic, partition, offset, config.fetchMaxBytes)
.maxWait(config.fetchWaitMaxMs)
.build();
FetchResponse fetchResponse = null;
SimpleConsumer simpleConsumer = null;
try {
simpleConsumer = findLeaderConsumer(partition);
if (simpleConsumer == null) {
// LOG.error(message);
return null;
}
fetchResponse = simpleConsumer.fetch(req);
} catch (Exception e) {
if (e instanceof ConnectException
|| e instanceof SocketTimeoutException
|| e instanceof IOException
|| e instanceof UnresolvedAddressException) {
LOG.warn("Network error when fetching messages:", e);
if (simpleConsumer != null) {
String host = simpleConsumer.host();
int port = simpleConsumer.port();
simpleConsumer = null;
throw new KafkaException(
"Network error when fetching messages: " + host + ":" + port + " , " + e.getMessage(),
e);
}
} else {
throw new RuntimeException(e);
}
}
if (fetchResponse.hasError()) {
short code = fetchResponse.errorCode(topic, partition);
if (code == ErrorMapping.OffsetOutOfRangeCode() && config.resetOffsetIfOutOfRange) {
long startOffset = getOffset(topic, partition, config.startOffsetTime);
offset = startOffset;
}
if (leaderBroker != null) {
LOG.error(
"fetch data from kafka topic["
+ config.topic
+ "] host["
+ leaderBroker.host()
+ ":"
+ leaderBroker.port()
+ "] partition["
+ partition
+ "] error:"
+ code);
} else {
}
return null;
} else {
ByteBufferMessageSet msgs = fetchResponse.messageSet(topic, partition);
return msgs;
}
}