private void CloseFetchersForQueues(
Cluster cluster,
IDictionary <string, IList <KafkaStream <TKey, TValue> > > messageStreams,
IEnumerable <BlockingCollection <FetchedDataChunk> > queuesToBeCleared)
{
var allPartitionInfos = parent.topicRegistry.Values.SelectMany(p => p.Values).ToList();
if (parent.fetcher != null)
{
parent.fetcher.StopConnections();
ClearFetcherQueues(allPartitionInfos, cluster, queuesToBeCleared, messageStreams);
Logger.Info("Committing all offsets after clearing the fetcher queues");
/**
* here, we need to commit offsets before stopping the consumer from returning any more messages
* from the current Data chunk. Since partition ownership is not yet released, this commit offsets
* call will ensure that the offsets committed now will be used by the next consumer thread owning the partition
* for the current Data chunk. Since the fetchers are already shutdown and this is the last chunk to be iterated
* by the consumer, there will be no more messages returned by this iterator until the rebalancing finishes
* successfully and the fetchers restart to fetch more Data chunks
**/
if (parent.Config.AutoCommitEnable)
{
parent.CommitOffsets();
}
}
}
public void TestBasic()
{
// test consumer timeout logic
var consumerConfig0 = TestUtils.CreateConsumerProperties(ZkConnect, Group, Consumer0, 200);
var zkConsumerConnector0 = new ZookeeperConsumerConnector(consumerConfig0);
var topicMessageSterams0 =
zkConsumerConnector0.CreateMessageStreams(
new Dictionary<string, int> { { Topic, 1 } }, new StringDecoder(), new StringDecoder());
// no messages to consume, we should hit timeout;
// also the iterator should support re-entrant, so loop it twice
for (var i = 0; i < 2; i++)
{
Assert.Throws<ConsumerTimeoutException>(
() => this.GetMessages(nMessages * 2, topicMessageSterams0));
}
zkConsumerConnector0.Shutdown();
// send some messages to each broker
var sentMessages1 =
this.SendMessagesToBrokerPartition(Configs.First(), Topic, 0, nMessages)
.Union(this.SendMessagesToBrokerPartition(Configs.Last(), Topic, 0, nMessages)).ToList();
// wait to make sure the topic and partition have a leader for the successful case
TestUtils.WaitUntilLeaderIsElectedOrChanged(this.ZkClient, Topic, 0, 500);
TestUtils.WaitUntilLeaderIsElectedOrChanged(this.ZkClient, Topic, 1, 500);
TestUtils.WaitUntilMetadataIsPropagated(this.Servers, Topic, 0, 1000);
TestUtils.WaitUntilMetadataIsPropagated(this.Servers, Topic, 1, 1000);
// create a consuemr
var consumerConfig1 = TestUtils.CreateConsumerProperties(ZkConnect, Group, Consumer1);
var zkConsumerConnector1 = new ZookeeperConsumerConnector(consumerConfig1);
var topicMessageStreams1 =
zkConsumerConnector1.CreateMessageStreams(
new Dictionary<string, int> { { Topic, 1 } }, new StringDecoder(), new StringDecoder());
var receivedMessages1 = this.GetMessages(nMessages * 2, topicMessageStreams1);
Assert.Equal(sentMessages1.OrderBy(x => x).ToArray(), receivedMessages1.OrderBy(x => x).ToArray());
// also check partition ownership
var actual_1 = this.GetZKChildrenValues(this.dirs.ConsumerOwnerDir);
var expected_1 = new List<Tuple<string, string>>
{
Tuple.Create("0", "group1_consumer1-0"),
Tuple.Create("1", "group1_consumer1-0")
};
Assert.Equal(expected_1, actual_1);
// commit consumer offsets
zkConsumerConnector1.CommitOffsets();
// create a consumer
var consumerConfig2 = TestUtils.CreateConsumerProperties(ZkConnect, Group, Consumer2);
consumerConfig2.RebalanceBackoffMs = RebalanceBackoutMs;
var zkConsumerConnector2 = new ZookeeperConsumerConnector(consumerConfig2);
var topicMessageStreams2 =
zkConsumerConnector2.CreateMessageStreams(
new Dictionary<string, int> { { Topic, 1 } }, new StringDecoder(), new StringDecoder());
// send some messages to each broker
var sentMessages2 =
this.SendMessagesToBrokerPartition(Configs.First(), Topic, 0, nMessages)
.Union(this.SendMessagesToBrokerPartition(Configs.Last(), Topic, 1, nMessages)).ToList();
// wait to make sure the topic and partition have a leader for the successful case
TestUtils.WaitUntilLeaderIsElectedOrChanged(this.ZkClient, Topic, 0, 500);
TestUtils.WaitUntilLeaderIsElectedOrChanged(this.ZkClient, Topic, 1, 500);
var receivedMessages2 =
this.GetMessages(nMessages, topicMessageStreams1)
.Union(this.GetMessages(nMessages, topicMessageStreams2))
.ToList();
Assert.Equal(sentMessages2.OrderBy(x => x).ToList(), receivedMessages2.OrderBy(x => x).ToList());
// also check partition ownership
var actual_2 = this.GetZKChildrenValues(this.dirs.ConsumerOwnerDir);
var expected_2 = new List<Tuple<string, string>>
{
Tuple.Create("0", "group1_consumer1-0"),
Tuple.Create("1", "group1_consumer2-0")
};
Assert.Equal(expected_2, actual_2);
// create a consumer with empty map
var consumerConfig3 = TestUtils.CreateConsumerProperties(ZkConnect, Group, Consumer3);
var zkConsumerConnector3 = new ZookeeperConsumerConnector(consumerConfig3);
zkConsumerConnector3.CreateMessageStreams(new Dictionary<string, int>());
// send some messages to each broker
var sentMessages3 =
this.SendMessagesToBrokerPartition(Configs.First(), Topic, 0, nMessages)
.Union(this.SendMessagesToBrokerPartition(Configs.Last(), Topic, 1, nMessages))
.ToList();
// wait to make sure the topic and partition have a leader for the successful case
TestUtils.WaitUntilLeaderIsElectedOrChanged(this.ZkClient, Topic, 0, 500);
TestUtils.WaitUntilLeaderIsElectedOrChanged(this.ZkClient, Topic, 1, 500);
var receivedMessages3 =
this.GetMessages(nMessages, topicMessageStreams1)
.Union(this.GetMessages(nMessages, topicMessageStreams2))
.ToList();
Assert.Equal(sentMessages3.OrderBy(x => x).ToList(), receivedMessages3.OrderBy(x => x).ToList());
// also check partition ownership
var actual_3 = this.GetZKChildrenValues(this.dirs.ConsumerOwnerDir);
Assert.Equal(expected_2, actual_3);
zkConsumerConnector1.Shutdown();
zkConsumerConnector2.Shutdown();
zkConsumerConnector3.Shutdown();
Logger.Info("all consumer connectors stopped");
}
internal void Consume()
{
// connects to zookeeper
using (ZookeeperConsumerConnector connector = new ZookeeperConsumerConnector(configSettings, true))
{
if (this.ThreadID == 0)
{
ConsumerGroupHelper.initialOffset = connector.GetOffset(cgOptions.Topic);
Logger.InfoFormat("======Original offset \r\n{0}", ConsumerGroupHelper.initialOffset == null ? "(NULL)" : ConsumeGroupMonitorHelper.GetComsumerGroupOffsetsAsLog(ConsumerGroupHelper.initialOffset));
}
// defines collection of topics and number of threads to consume it with
// ===============NOTE============================
// For example , if there is 80 partitions for one topic.
//
// Normally start more than 96 = 80*120% clients with same GroupId. ( the extra 20% are buffer for autopilot IMP). And set FetchThreadCountPerConsumer as 1.
// Then 80 clients can lock partitions, can set MACHINENAME_ProcessID as ConsumerId, other 16 are idle. Strongly recomand take this method.
//
// If start 40 clients, and set FetchThreadCountPerConsumer as 1. then every client can lock 2 partitions at least. And if some client not available for autopilot
// IMP reason, then some of the client maybe lock 3 partitions.
//
// If start 40 clients, and set FetchThreadCountPerConsumer as 2, you will get two IEnumerator<Message>:topicData[0].GetEnumerator(),topicData[1].GetEnumerator()
// you need start TWO threads to process them in dependently.
// If the client get 2 partitions, each thread will handle 1 partition,
// If the client get 3 partitions, then one thread get 2 partitions, the other one get 1 partition. It will make the situaiton complex and the consume of partition not balance.
//==================NOTE=============================
IDictionary<string, int> topicMap = new Dictionary<string, int> { { cgOptions.Topic, cgOptions.FetchThreadCountPerConsumer } };
// get references to topic streams.
IDictionary<string, IList<KafkaMessageStream<Message>>> streams = connector.CreateMessageStreams(topicMap, new DefaultDecoder());
IList<KafkaMessageStream<Message>> topicData = streams[cgOptions.Topic];
long latestTotalCount = 0;
bool hitEndAndCommited = false;
if (cgOptions.CancellationTimeoutMs == KafkaNETExampleConstants.DefaultCancellationTimeoutMs)
{
// Get the message enumerator.
IEnumerator<Message> messageEnumerator = topicData[0].GetEnumerator();
//TODO: the enumerator count equal with FetchThreadCountPerConsumer . For example, if that value is 5, then here should get 5 enumerator.
//IF have 100 partitions, and only 20 consumers, need set this value to 5. and start 5 thread handle each one.
// Add tuples until maximum receive message count is reached or no new messages read after consumer configured timeout.
while (true)
{
bool noMoreMessage = false;
try
{
messageEnumerator.MoveNext();
Message m = messageEnumerator.Current;
latestTotalCount = Interlocked.Increment(ref ConsumerGroupHelper.totalCount);
Logger.InfoFormat("Message {0} from Partition:{1}, Offset:{2}, key:{3}, value:{4}", latestTotalCount, m.PartitionId, m.Offset, m.Key == null ? "(null)" : Encoding.UTF8.GetString(m.Key), m.Payload == null ? "(null)" : Encoding.UTF8.GetString(m.Payload));
if (latestTotalCount == 1)
{
Logger.InfoFormat("Read FIRST message, it's offset: {0} PartitionID:{1}", m.Offset, ((ConsumerIterator<Message>)messageEnumerator).currentTopicInfo.PartitionId);
}
hitEndAndCommited = false;
if (latestTotalCount % cgOptions.CommitBatchSize == 0)
{
//NOTE======
//Normally, just directly call .CommitOffsets()
// CommitOffset(string topic, int partition, long offset) only used when customer has strong requirement for reprocess messages as few as possible.
//Need tune the frequecy of calling .CommitOffsets(), it will directly increate zookeeper load and impact your overall performance
if (cgOptions.CommitOffsetWithPartitionIDOffset)
connector.CommitOffset(cgOptions.Topic, m.PartitionId.Value, m.Offset);
else
connector.CommitOffsets();
Console.WriteLine("\tRead some and commit once, LATEST message offset: {0}. PartitionID:{1} -- {2} Totally read {3} will commit offset. {4} FetchOffset:{5} ConsumeOffset:{6} CommitedOffset:{7}"
, m.Offset, m.PartitionId.Value, ((ConsumerIterator<Message>)messageEnumerator).currentTopicInfo.PartitionId, latestTotalCount, DateTime.Now
, ((ConsumerIterator<Message>)messageEnumerator).currentTopicInfo.FetchOffset
, ((ConsumerIterator<Message>)messageEnumerator).currentTopicInfo.ConsumeOffset
, ((ConsumerIterator<Message>)messageEnumerator).currentTopicInfo.CommitedOffset);
}
if (cgOptions.Count > 0 && latestTotalCount >= cgOptions.Count)
{
Logger.InfoFormat("Read LAST message, it's offset: {0}. PartitionID:{1} Totally read {2} want {3} will exit.", m.Offset, ((ConsumerIterator<Message>)messageEnumerator).currentTopicInfo.PartitionId, latestTotalCount, cgOptions.Count);
break;
}
}
catch (ConsumerTimeoutException)
{
if (!hitEndAndCommited)
{
Logger.InfoFormat("Totally Read {0} will commit offset. {1}", latestTotalCount, DateTime.Now);
connector.CommitOffsets();
hitEndAndCommited = true;
}
// Thrown if no new messages read after consumer configured timeout.
noMoreMessage = true;
}
if (noMoreMessage)
{
Logger.InfoFormat("No more message , hit end ,will Sleep(1), {0}", DateTime.Now);
if (cgOptions.SleepTypeWhileAlwaysRead == 0)
Thread.Sleep(0);
else if (cgOptions.SleepTypeWhileAlwaysRead == 1)
Thread.Sleep(1); //Best choice is Thread.Sleep(1). Other 3 choice still make the CPU 100%
else if (cgOptions.SleepTypeWhileAlwaysRead == 2)
Thread.Yield();
else
{
}
}
}
}
else
{
//Siphon scenario, repeatly take some messages and process. if no enough messages, will stop current batch after timeout.
while (true)
{
#if NET45
bool noMoreMessage = false;
Message lastMessage = null;
int count = 0;
KafkaMessageStream<Message> messagesStream = null;
ConsumerIterator<Message> iterator = null;
using (CancellationTokenSource cancellationTokenSource = new CancellationTokenSource(cgOptions.CancellationTimeoutMs))
{
lastMessage = null;
IEnumerable<Message> messages = topicData[0].GetCancellable(cancellationTokenSource.Token);
messagesStream = (KafkaMessageStream<Message>)messages;
iterator = (ConsumerIterator<Message>)messagesStream.iterator;
foreach (Message message in messages)
{
latestTotalCount = Interlocked.Increment(ref ConsumerGroupHelper.totalCount);
lastMessage = message;
if (latestTotalCount == 1)
{
PartitionTopicInfo p = iterator.currentTopicInfo;
Logger.InfoFormat("Read FIRST message, it's offset: {0} PartitionID:{1}", lastMessage.Offset, p == null ? "null" : p.PartitionId.ToString());
}
hitEndAndCommited = false;
if (++count >= cgOptions.CommitBatchSize)
{
cancellationTokenSource.Cancel();
}
}
}
if (count > 0)
{
connector.CommitOffsets();
consumedTotalCount += count;
PartitionTopicInfo p = iterator.currentTopicInfo;
Console.WriteLine("\tRead some and commit once, Thread: {8} consumedTotalCount:{9} Target:{10} LATEST message offset: {0}. PartitionID:{1} -- {2} Totally read {3} will commit offset. {4} FetchOffset:{5} ConsumeOffset:{6} CommitedOffset:{7}"
, lastMessage.Offset, lastMessage.PartitionId.Value, p == null ? "null" : p.PartitionId.ToString(), latestTotalCount, DateTime.Now
, p == null ? "null" : p.FetchOffset.ToString()
, p == null ? "null" : p.ConsumeOffset.ToString()
, p == null ? "null" : p.CommitedOffset.ToString()
, this.ThreadID
, this.consumedTotalCount
, this.Count);
}
else
{
noMoreMessage = true;
}
if (this.Count > 0 && consumedTotalCount >= this.Count)
{
Logger.InfoFormat("Current thrad Read LAST message, Totally read {0} want {1} will exit current thread.", consumedTotalCount, this.Count);
break;
}
if (noMoreMessage)
{
Logger.InfoFormat("No more message , hit end ,will Sleep(2000), {0}", DateTime.Now);
if (cgOptions.SleepTypeWhileAlwaysRead == 0)
Thread.Sleep(0);
else if (cgOptions.SleepTypeWhileAlwaysRead == 1)
Thread.Sleep(2000); //Best choice is Thread.Sleep(1). Other 3 choice still make the CPU 100%
else if (cgOptions.SleepTypeWhileAlwaysRead == 2)
Thread.Yield();
else
{
}
}
#endif
#if NET4
throw new NotSupportedException("Please use .net45 to compile .");
#endif
}
}
Logger.InfoFormat("Read {0} will commit offset. {1}", latestTotalCount, DateTime.Now);
connector.CommitOffsets();
latestTotalCount = Interlocked.Read(ref ConsumerGroupHelper.totalCount);
Logger.InfoFormat("Totally read {0} want {1} . ", latestTotalCount, cgOptions.Count);
if (this.ThreadID == 0)
{
ConsumerGroupHelper.newOffset = connector.GetOffset(cgOptions.Topic);
}
}
this.resetEvent.Set();
}