Ambiguous entry in docs

[Алекс Турс <go...@gmail.com>]

Hi.

I read (mostly) all documentation top to bottom and happened to stumble
upon passage I cannot understand. It states:

https://kafka.apache.org/documentation/#impl_consumerregistration

"If the consumer creates a message stream using a topic filter, it also
registers a watch on changes (new topics being added) under the broker
topic registry. (Each change will trigger re-evaluation of the available
topics to determine which topics are allowed by the topic filter. A new
allowed topic will trigger rebalancing among all consumers within the
consumer group.)"

So, what are these topic filters? And what is message stream for consumer?
Googling on that shows couple of SO questions and rare links to streams api.

Best regards,

Alex

Re: Ambiguous entry in docs

[Kamal <ka...@gmail.com>]

A consumer can read data from multiple topics. The above line describes the
usage of
topic regex in which an existing consumer can read data from newly (yet-to)
created topics.
For more details, see

https://kafka.apache.org/0100/javadoc/org/apache/kafka/clients/consumer/KafkaConsumer.html#subscribe(java.util.regex.Pattern,%20org.apache.kafka.clients.consumer.ConsumerRebalanceListener)



On Wed, Jan 17, 2018 at 1:29 PM, Алекс Турс <go...@gmail.com>
wrote:

> Hi.
>
> I read (mostly) all documentation top to bottom and happened to stumble
> upon passage I cannot understand. It states:
>
> https://kafka.apache.org/documentation/#impl_consumerregistration
>
> "If the consumer creates a message stream using a topic filter, it also
> registers a watch on changes (new topics being added) under the broker
> topic registry. (Each change will trigger re-evaluation of the available
> topics to determine which topics are allowed by the topic filter. A new
> allowed topic will trigger rebalancing among all consumers within the
> consumer group.)"
>
> So, what are these topic filters? And what is message stream for consumer?
> Googling on that shows couple of SO questions and rare links to streams
> api.
>
> Best regards,
>
> Alex
>