Hello all,
I have updated the KIP with following changes
1. HeaderFrom.headers should allow duplicate values, so I have removed it from
the KIP.
FYI, the reference test case[1].
2. The log.dir configuration already allows multiple values under the existing
logic [2].
Therefore, we propose updating its type from STRING to LIST, changing the
default
value from "/tmp/kafka-logs" to List.of("/tmp/kafka-logs"). In addition, we
update its
validator from null to anyNonDuplicateValues(isNullAllowed = true,
isEmptyAllowed = false).
[1]:
https://github.com/apache/kafka/blob/eba9839776c07e860c9aa7fe2d028e4f65031d5b/connect/transforms/src/test/java/org/apache/kafka/connect/transforms/HeaderFromTest.java#L251
[2]:
https://github.com/apache/kafka/blob/eba9839776c07e860c9aa7fe2d028e4f65031d5b/server/src/main/java/org/apache/kafka/server/config/AbstractKafkaConfig.java#L82
Best Regards,
Jiunn-Yang
> Jun Rao <[email protected]> 於 2025年8月22日 凌晨3:06 寫道：
>
> Hi, Jiunn-Yang,
>
> Thanks for the reply. The changes look good to me and we can follow up on
> the 0.0.0.0 issue separately in KIP-1202.
>
> Jun
>
> On Thu, Aug 21, 2025 at 6:55 AM 黃竣陽 <[email protected]> wrote:
>
>> Hello Jun, chia,
>>
>>> (By the way, the table in KIP-1202 has an incorrect value — null is
>> acceptable for both cases.)
>>
>> KIP-1202 covers the scenario where the listeners configuration is set to
>> the special
>> value PLAINTEXT://0.0.0.0:9092. In this case, if advertised.listeners is
>> configured as null,
>> an IllegalArgumentException will be thrown: requirement failed:
>> advertised.listeners cannot
>> use the non-routable meta-address 0.0.0.0. Use a routable IP address.
>>
>>> If we want to address `advertised.listeners` in this KIP, it would be
>> better to also have the controller reject an `empty` value
>>
>> Yes, I fully agree that we should disallow an empty list for this
>> configuration, since specifying an
>> empty list is odd, it would mean that the node does not advertise any
>> listener addresses,
>> making it unreachable by clients. I will updated KIP according by this.
>>
>> Best Regards,
>> Jiunn-Yang
>>
>>> Chia-Ping Tsai <[email protected]> 於 2025年8月21日 晚上8:48 寫道：
>>>
>>> 2. It seems that advertised.listeners should default to null and can't be
>>>
>>> That is an inconsistency between the broker and controller, and it will
>> be addressed by KIP-1202. `null` is valid for both, while `empty` is valid
>> only for the controller. As Jun mentioned, the broker encounters an error
>> in this case.
>>> (By the way, the table in KIP-1202 has an incorrect value — null is
>> acceptable for both cases.)
>>>
>>> If we want to address `advertised.listeners` in this KIP, it would be
>> better to also have the controller reject an `empty` value
>>>
>>> Best,
>>> Chia-Ping
>>>
>>> On 2025/08/20 18:01:35 Jun Rao wrote:
>>>> Hi, Jiunn-Yang,
>>>>
>>>> Thanks for the update.
>>>>
>>>> 1. Sounds good.
>>>>
>>>> 2. It seems that advertised.listeners should default to null and can't
>> be
>>>> empty. Currently, if it's set to empty, it fails with the following.
>>>>
>>>> java.lang.IllegalArgumentException: requirement failed: There must be at
>>>> least one broker advertised listener. Perhaps all listeners appear in
>>>> controller.listener.names?
>>>> at scala.Predef$.require(Predef.scala:337)
>> ~[scala-library-2.13.16.jar:?]
>>>> at
>>>>
>> kafka.server.KafkaConfig.validateAdvertisedBrokerListenersNonEmptyForBroker$1(KafkaConfig.scala:545)
>>>> ~[kafka_2.13-4.2.0-SNAPSHOT.jar:?]
>>>>
>>>> Jun
>>>>
>>>> On Wed, Aug 20, 2025 at 4:58 AM 黃竣陽 <[email protected]> wrote:
>>>>
>>>>> Hello Jun,
>>>>>
>>>>> I have updated the KIP with the following changes.
>>>>>
>>>>> 1. The type of controller.listener.names should be changed from string
>> to
>>>>> list.
>>>>> Its default value should be updated from null to NO_DEFAULT_VALUE, and
>> its
>>>>> validator should be updated to anyNonDuplicateValues(isNullAllowed =
>>>>> false, isEmptyAllowed = false).
>>>>>
>>>>> 2. The type of advertised.listeners should be changed from string to
>> list.
>>>>> As for its validator,
>>>>> I think we can continue the discussion in KIP-1202.
>>>>>
>>>>> Best Regards,
>>>>> Jiunn-Yang
>>>>>
>>>>>> Jun Rao <[email protected]> 於 2025年8月14日 凌晨12:37 寫道：
>>>>>>
>>>>>> Hi, Jiunn-Yang,
>>>>>>
>>>>>> Thanks for the updated KIP. Looks good to me.
>>>>>>
>>>>>> Jun
>>>>>>
>>>>>> On Wed, Aug 13, 2025 at 3:08 AM 黃竣陽 <[email protected]> wrote:
>>>>>>
>>>>>>> Hello Jun,
>>>>>>>
>>>>>>> Thanks for the reply.
>>>>>>>
>>>>>>> I have updated the KIP according there comments.
>>>>>>>
>>>>>>> Best Regards,
>>>>>>> Jiunn-Yang
>>>>>>>
>>>>>>>> Jun Rao <[email protected]> 於 2025年8月13日 凌晨1:57 寫道：
>>>>>>>>
>>>>>>>> Hi, Jiunn-Yang,
>>>>>>>>
>>>>>>>> Thanks for the reply. A few more comments.
>>>>>>>>
>>>>>>>> JR50. It seems that you changed the default value for
>> config.providers
>>>>>>>> incorrectly. The change is meant for bootstrap.servers.
>>>>>>>>
>>>>>>>> JR51. Could you document the current behavior if bootstrap.servers
>> is
>>>>>>> empty
>>>>>>>> in ConsumerConfig, WorkerConfig, ProducerConfig and StreamsConfig?
>>>>>>>>
>>>>>>>> JR52. Could you document the justification for changing the default
>>>>> value
>>>>>>>> for bootstrap.servers in WorkerConfig?
>>>>>>>>
>>>>>>>> JR53. It seems that WorkerConfig is not public facing. Only classes
>> in
>>>>>>>> connect api are public. So, there is no need to document the
>>>>> deprecation
>>>>>>>> of BOOTSTRAP_SERVERS_DEFAULT in WorkerConfig.
>>>>>>>>
>>>>>>>> Jun
>>>>>>>>
>>>>>>>>
>>>>>>>> On Tue, Aug 12, 2025 at 8:14 AM 黃竣陽 <[email protected]> wrote:
>>>>>>>>
>>>>>>>>> Hi chia,
>>>>>>>>>
>>>>>>>>> I have updated the KIP with these changes.
>>>>>>>>>
>>>>>>>>> Best Regards,
>>>>>>>>> Jiunn-Yang
>>>>>>>>>
>>>>>>>>>> Chia-Ping Tsai <[email protected]> 於 2025年8月12日 晚上9:54 寫道：
>>>>>>>>>>
>>>>>>>>>> hi Jiunn
>>>>>>>>>>
>>>>>>>>>>> 黃竣陽 <[email protected]> 於 2025年8月12日 下午6:18 寫道：
>>>>>>>>>>>
>>>>>>>>>>> 3. WorkerConfig – Change the default value of bootstrap.servers
>> from
>>>>>>>>> "localhost:9092" to NO_DEFAULT_VALUE
>>>>>>>>>>> and deprecate the constant BOOTSTRAP_SERVERS_DEFAULT.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> I agree that the default value of “localhost:9092” is strange.
>>>>> However,
>>>>>>>>> it is still a breaking change, so please highlight this change in
>> the
>>>>>>> KIP.
>>>>>>>>>>
>>>>>>>>>> Best,
>>>>>>>>>> Chia-Ping
>>>>>>>>>
>>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>
>>>>>
>>>>
>>
>>
