We are on Kafka 0.10.0.1 (server and client) and use Java
consumer/producer APIs. We have an application where we create Kafka topics
dynamically (using the AdminUtils Java API) and then start
producing/consuming on those topics. The issue we frequently run into is
this:
1. Application process creates a topic "foo-bar" via
AdminUtils.createTopic. This is sucessfully completed.
2. Same application process then creates a consumer (using new Java
consumer API) on that foo-bar topic as a next step.
3. The consumer that gets created in step#2 however, doesn't seem to be
enrolled in consumer group for this topic because of this (notice the last
line in the log):
2017-02-21 00:58:43,359 [Thread-6] DEBUG
org.apache.kafka.clients.consumer.KafkaConsumer
- Kafka consumer created
2017-02-21 00:58:43,360 [Thread-6] DEBUG
org.apache.kafka.clients.consumer.KafkaConsumer
- Subscribed to topic(s): foo-bar
2017-02-21 00:58:43,543 [Thread-6] DEBUG org.apache.kafka.clients.consu
mer.internals.AbstractCoordinator - Received group coordinator response
ClientResponse(receivedTimeMs=1487667523542, disconnected=false,
request=ClientRequest(expectResponse=true, callback=org.apache.kafka.clie
nts.consumer.internals.ConsumerNetworkClient$RequestFutureCo
mpletionHandler@50aad50f, request=RequestSend(header={ap
i_key=10,api_version=0,correlation_id=0,client_id=consumer-1},
body={group_id=my-app-group}), createdTimeMs=1487667523378,
sendTimeMs=1487667523529), responseBody={error_code=0,coo
rdinator={node_id=0,host=localhost,port=9092}})
2017-02-21 00:58:43,543 [Thread-6] INFO org.apache.kafka.clients.consu
mer.internals.AbstractCoordinator - Discovered coordinator
localhost:9092 (id: 2147483647 rack: null) for group my-app-group.
2017-02-21 00:58:43,545 [Thread-6] INFO org.apache.kafka.clients.consu
mer.internals.ConsumerCoordinator - Revoking previously assigned
partitions [] for group my-app-group
2017-02-21 00:58:43,545 [Thread-6] INFO org.apache.kafka.clients.consu
mer.internals.AbstractCoordinator - (Re-)joining group my-app-group
2017-02-21 00:58:43,548 [Thread-6] DEBUG org.apache.kafka.clients.consu
mer.internals.AbstractCoordinator - Sending JoinGroup
({group_id=my-app-group,session_timeout=30000,member_id=,
protocol_type=consumer,group_protocols=[{protocol_name=
range,protocol_metadata=java.nio.HeapByteBuffer[pos=0 lim=59 cap=59]}]})
to coordinator localhost:9092 (id: 2147483647 <(214)%20748-3647> rack:
null)
2017-02-21 00:58:43,548 [Thread-6] DEBUG org.apache.kafka.common.metrics.Metrics
- Added sensor with name node-2147483647.bytes-sent
2017-02-21 00:58:43,549 [Thread-6] DEBUG org.apache.kafka.common.metrics.Metrics
- Added sensor with name node-2147483647.bytes-received
2017-02-21 00:58:43,549 [Thread-6] DEBUG org.apache.kafka.common.metrics.Metrics
- Added sensor with name node-2147483647.latency
2017-02-21 00:58:43,552 [Thread-6] DEBUG org.apache.kafka.clients.consu
mer.internals.AbstractCoordinator - Received successful join group
response for group my-app-group: {error_code=0,generation_id=1,
group_protocol=range,leader_id=consumer-1-1453e523-402a-43fe
-87e8-795ae4c68c5d,member_id=consumer-1-1453e523-402a-43fe-
87e8-795ae4c68c5d,members=[{member_id=consumer-1-1453e523-
402a-43fe-87e8-795ae4c68c5d,member_metadata=java.nio.HeapByteBuffer[pos=0
lim=59 cap=59]}]}
2017-02-21 00:58:43,552 [Thread-6] DEBUG org.apache.kafka.clients.consu
mer.internals.ConsumerCoordinator - Performing assignment for group
my-app-group using strategy range with subscriptions
{consumer-1-1453e523-402a-43fe-87e8-795ae4c68c5d=Subscriptio
n(topics=[foo-bar])}
*2017-02-21 00:58:43,552 [Thread-6] DEBUG org.apache.kafka.clients.consu
mer.internals.AbstractPartitionAssignor - Skipping assignment for topic
foo-bar since no metadata is available*
4. A few seconds later, a separate process, produces (via Java producer
API) on the foo-bar topic, some messages.
5. The consumer created in step#2 (although is waiting for messages) on
the foo-bar topic, _doesn't_ consume these messages.
6. *5 minutes later* the Kafka server triggers a consumer rebalance which
then successfully assigns partition(s) of this foo-bar topic to consumer
created in step#2 and the consumer start consuming these messages.
This 5 minute delay in consuming messages from this dynamically created
topic is what we want to avoid. Is there anyway I can deterministically
do/force creation of a dynamic topic and be assured that upon completion of
that call, I can create a consumer and start consuming of that topic such
that it can receive messages as soon as the messages are produced on that
topic, without having to wait for a 5 minute delay (or whatever the
rebalance configuration is)? In essence, is there a way to ensure that the
Kafka consumer does get the topic metadata for a topic that was created
successfully by the same application, immediately?
P.S: We have topic auto creation disabled, so this isn't really a auto
topic creation issue. In our case we are explicitly invoking the create
topic operation via the Java API.
-Jaikiran
