protected boolean get(KafkaETLKey key, BytesWritable value) throws IOException {
if (_messageIt != null && _messageIt.hasNext()) {
MessageAndOffset messageAndOffset = _messageIt.next();
ByteBuffer buf = messageAndOffset.message().buffer();
int origSize = buf.remaining();
byte[] bytes = new byte[origSize];
buf.get(bytes, buf.position(), origSize);
value.set(bytes, 0, origSize);
key.set(_index, _offset, messageAndOffset.message().checksum());
_offset = messageAndOffset.nextOffset(); // increase offset
_count++; // increase count
return true;
} else return false;
}
public void run(
long a_maxReads, String a_topic, int a_partition, List<String> a_seedBrokers, int a_port)
throws Exception {
// find the meta data about the topic and partition we are interested in
//
PartitionMetadata metadata = findLeader(a_seedBrokers, a_port, a_topic, a_partition);
if (metadata == null) {
System.out.println("Can't find metadata for Topic and Partition. Exiting");
return;
}
if (metadata.leader() == null) {
System.out.println("Can't find Leader for Topic and Partition. Exiting");
return;
}
String leadBroker = metadata.leader().host();
String clientName = "Client_" + a_topic + "_" + a_partition;
SimpleConsumer consumer = new SimpleConsumer(leadBroker, a_port, 100000, 64 * 1024, clientName);
long readOffset =
getLastOffset(
consumer, a_topic, a_partition, kafka.api.OffsetRequest.EarliestTime(), clientName);
int numErrors = 0;
while (a_maxReads > 0) {
if (consumer == null) {
consumer = new SimpleConsumer(leadBroker, a_port, 100000, 64 * 1024, clientName);
}
FetchRequest req =
new FetchRequestBuilder()
.clientId(clientName)
.addFetch(
a_topic,
a_partition,
readOffset,
100000) // Note: this fetchSize of 100000 might need to
// be increased if large batches are written to
// Kafka
.build();
FetchResponse fetchResponse = consumer.fetch(req);
if (fetchResponse.hasError()) {
numErrors++;
// Something went wrong!
short code = fetchResponse.errorCode(a_topic, a_partition);
System.out.println(
"Error fetching data from the Broker:" + leadBroker + " Reason: " + code);
if (numErrors > 5) {
break;
}
if (code == ErrorMapping.OffsetOutOfRangeCode()) {
// We asked for an invalid offset. For simple case ask for the last element to reset
readOffset =
getLastOffset(
consumer, a_topic, a_partition, kafka.api.OffsetRequest.LatestTime(), clientName);
continue;
}
consumer.close();
consumer = null;
leadBroker = findNewLeader(leadBroker, a_topic, a_partition, a_port);
continue;
}
numErrors = 0;
long numRead = 0;
for (MessageAndOffset messageAndOffset : fetchResponse.messageSet(a_topic, a_partition)) {
long currentOffset = messageAndOffset.offset();
if (currentOffset < readOffset) {
System.out.println("Found an old offset: " + currentOffset + " Expecting: " + readOffset);
continue;
}
readOffset = messageAndOffset.nextOffset();
ByteBuffer payload = messageAndOffset.message().payload();
byte[] bytes = new byte[payload.limit()];
payload.get(bytes);
System.out.println(
String.valueOf(messageAndOffset.offset()) + ": " + new String(bytes, "UTF-8"));
numRead++;
a_maxReads--;
}
if (numRead == 0) {
try {
Thread.sleep(1000);
} catch (InterruptedException ie) {
}
}
}
if (consumer != null) {
consumer.close();
}
}