public void TestTopicMetadataRequest()
{
// create topic
var topic = "test";
AdminUtils.CreateTopic(this.ZkClient, topic, 1, 1, new Dictionary<string, string>());
// create a topic metadata request
var topicMetadataRequest = new TopicMetadataRequest(new List<string> { topic }, 0);
var serializedMetadataRequest = ByteBuffer.Allocate(topicMetadataRequest.SizeInBytes + 2);
topicMetadataRequest.WriteTo(serializedMetadataRequest);
serializedMetadataRequest.Rewind();
var deserializedMetadataRequest = TopicMetadataRequest.ReadFrom(serializedMetadataRequest);
Assert.Equal(topicMetadataRequest, deserializedMetadataRequest);
}
/// <summary>
/// Used by the producer to send a metadata request since it has access to the ProducerConfig
/// </summary>
/// <param name="topics">The topics for which the metadata needs to be fetched</param>
/// <param name="brokers">The brokers in the cluster as configured on the client</param>
/// <param name="producerConfig">The producer's config</param>
/// <param name="correlationId">topic metadata response</param>
/// <returns></returns>
public static TopicMetadataResponse FetchTopicMetadata(
ISet<string> topics, IList<Broker> brokers, ProducerConfig producerConfig, int correlationId)
{
var fetchMetaDataSucceeded = false;
var i = 0;
var topicMetadataRequest = new TopicMetadataRequest(
TopicMetadataRequest.CurrentVersion, correlationId, producerConfig.ClientId, topics.ToList());
TopicMetadataResponse topicMetadataResponse = null;
Exception t = null;
// shuffle the list of brokers before sending metadata requests so that most requests don't get routed to the same broker
var shuffledBrokers = brokers.Shuffle();
while (i < shuffledBrokers.Count() && !fetchMetaDataSucceeded)
{
var producer = ProducerPool.CreateSyncProducer(producerConfig, shuffledBrokers[i]);
Logger.InfoFormat("Fetching metadata from broker {0} with correlation id {1} for {2} topic(s) {3}", shuffledBrokers[i], correlationId, topics.Count, string.Join(",", topics));
try
{
topicMetadataResponse = producer.Send(topicMetadataRequest);
fetchMetaDataSucceeded = true;
}
catch (Exception e)
{
Logger.Warn(string.Format("Fetching topic metadata with correlation id {0} for topic [{1}] from broker [{2}] failed", correlationId, topics, shuffledBrokers[i]), e);
t = e;
}
finally
{
i++;
producer.Dispose();
}
}
if (!fetchMetaDataSucceeded)
{
throw new KafkaException(
string.Format(
"fetching topic metadata for topics [{0}] from broker [{1}] failed", string.Join(",", topics), string.Join(", ", shuffledBrokers)),
t);
}
Logger.DebugFormat("Successfully fetched metadata for {0} topic(s) {1}", topics.Count(), string.Join(",", topics));
return topicMetadataResponse;
}
public TopicMetadataResponse Send(TopicMetadataRequest request)
{
var response = this.DoSend(request);
return TopicMetadataResponse.ReadFrom(response.Buffer);
}
protected bool Equals(TopicMetadataRequest other)
{
return this.VersionId == other.VersionId && this.CorrelationId == other.CorrelationId
&& string.Equals(this.ClientId, other.ClientId) && this.Topics.SequenceEqual(other.Topics);
}
protected bool Equals(TopicMetadataRequest other)
{
return(this.VersionId == other.VersionId && this.CorrelationId == other.CorrelationId &&
string.Equals(this.ClientId, other.ClientId) && this.Topics.SequenceEqual(other.Topics));
}
public RequestResponseSerializationTest()
{
this.producerRequest = SerializationTestUtils.CreateTestProducerRequest();
this.producerResponse = SerializationTestUtils.CreateTestProducerResponse();
this.fetchRequest = SerializationTestUtils.CreateTestFetchRequest();
this.offsetRequest = SerializationTestUtils.CreateTestOffsetRequest();
this.offsetResponse = SerializationTestUtils.CreateTestOffsetResponse();
this.topicMetadataRequest = SerializationTestUtils.CreateTestTopicMetadataRequest();
this.topicMetadataResponse = SerializationTestUtils.CreateTestTopicMetadataResponse();
}
