First of all, sorry to arrive late on this. Jun, do you have a reference that states that "purge" means to remove a portion? If I do "define: purge" on Google, one of the definitions is "physically remove (something) completely."
In the PR, I was asking about the reasoning more than suggesting a change. But let me clarify my thoughts. There are 2 separate things to think about: 1. The protocol change. It's currently called Purge with no mention of what it's purging. This is consistent with Fetch and Produce and it makes sense if we reserve the word "Purge" for dealing with records/messages. Having said that, I don't think this is particularly intuitive for people who are not familiar with Kafka and its history. The number of APIs in the protocol keeps growing and it would be better to be explicit about what is being purged/deleted, in my opinion. If we are explicit, then we need to decide what to call it, since there is no precedent. A few options: PurgeRecords, PurgeMessages, PurgeData, DeleteRecords, DeleteMessages, DeleteData (I personally don't like the Data suffix as it's not used anywhere else). 2. The AdminClient change. Regarding the name of the method, I'd prefer to avoid the `Data` suffix because I don't think we use that anywhere else (please correct me if I'm wrong). In the Producer, we have `send(ProduceRecord)` and in the consumer we have `ConsumerRecords poll(...)`. So maybe, the suffix should be `Records`? Like in the protocol, we still need to decide if we want to use `purge` or `delete`. We seem to use `delete` for all the other methods in the AdminClient, so unless we have a reason to use a different name, it seems like we should be consistent. The proposed method signature is `Future<Map<TopicPartition, PurgeDataResult>> purgeDataBefore(Map<TopicPartition, Long> offsetForPartition)`. In the AdminClient KIP (KIP-117), we are using classes to encapsulate the parameters and result. We should probably do the same in this KIP for consistency. Once we do that, we should also consider if `Before` should be in the method name or should be in the parameter class. Just an example to describe what I mean, one could say `deleteRecords(DeleteRecordsParams.before(offsetsForPartition)`. That way, we could provide a different way of deleting by simply updating the parameters class. Some food for thought. :) Ismael On Thu, Mar 2, 2017 at 5:46 PM, Dong Lin <lindon...@gmail.com> wrote: > Hey Jun, > > Thanks for this information. I am not aware of this difference between the > purge and delete. Given this difference, I will prefer to the existing name > of the purge. > > Ismael, please let me if you are strong about using delete. > > Thanks, > Dong > > > On Thu, Mar 2, 2017 at 9:40 AM, Jun Rao <j...@confluent.io> wrote: > > > Hi, Dong, > > > > It seems that delete means removing everything while purge means > removing a > > portion. So, it seems that it's better to be able to distinguish the two? > > > > Thanks, > > > > Jun > > > > On Wed, Mar 1, 2017 at 1:57 PM, Dong Lin <lindon...@gmail.com> wrote: > > > > > Hi all, > > > > > > I have updated the KIP to include a script that allows user to purge > data > > > by providing a map from partition to offset. I think this script may be > > > convenience and useful, e.g., if user simply wants to purge all data of > > > given partitions from command line. I am wondering if anyone object > this > > > script or has suggestions on the interface. > > > > > > Besides, Ismael commented in the pull request that it may be better to > > > rename PurgeDataBefore() to DeleteDataBefore() and rename PurgeRequest > to > > > DeleteRequest. I think it may be a good idea because kafka-topics.sh > > > already use "delete" as an option. Personally I don't have strong > > > preference between "purge" and "delete". I am wondering if anyone > object > > to > > > this change. > > > > > > Thanks, > > > Dong > > > > > > > > > > > > On Wed, Mar 1, 2017 at 9:46 AM, Dong Lin <lindon...@gmail.com> wrote: > > > > > > > Hi Ismael, > > > > > > > > I actually mean log_start_offset. I realized that it is a better name > > > > after I start implementation because "logStartOffset" is already used > > in > > > > Log.scala and LogCleanerManager.scala. So I changed it from > > > > log_begin_offset to log_start_offset in the patch. But I forgot to > > update > > > > the KIP and specify it in the mailing thread. > > > > > > > > Thanks for catching this. Let me update the KIP to reflect this > change. > > > > > > > > Dong > > > > > > > > > > > > On Wed, Mar 1, 2017 at 6:15 AM, Ismael Juma <ism...@juma.me.uk> > wrote: > > > > > > > >> Hi Dong, > > > >> > > > >> When you say "logStartOffset", do you mean "log_begin_offset "? I > > could > > > >> only find the latter in the KIP. If so, would log_start_offset be a > > > better > > > >> name? > > > >> > > > >> Ismael > > > >> > > > >> On Tue, Feb 28, 2017 at 4:26 AM, Dong Lin <lindon...@gmail.com> > > wrote: > > > >> > > > >> > Hi Jun and everyone, > > > >> > > > > >> > I would like to change the KIP in the following way. Currently, if > > any > > > >> > replica if offline, the purge result for a partition will > > > >> > be NotEnoughReplicasException and its low_watermark will be 0. The > > > >> > motivation for this approach is that we want to guarantee that the > > > data > > > >> > before purgedOffset has been deleted on all replicas of this > > partition > > > >> if > > > >> > purge result indicates success. > > > >> > > > > >> > But this approach seems too conservative. It should be sufficient > in > > > >> most > > > >> > cases to just tell user success and set low_watermark to minimum > > > >> > logStartOffset of all live replicas in the PurgeResponse if > > > >> logStartOffset > > > >> > of all live replicas have reached purgedOffset. This is because > for > > an > > > >> > offline replicas to become online and be elected leader, it should > > > have > > > >> > received one FetchReponse from the current leader which should > tell > > it > > > >> to > > > >> > purge beyond purgedOffset. The benefit of doing this change is > that > > we > > > >> can > > > >> > allow purge operation to succeed when some replica is offline. > > > >> > > > > >> > Are you OK with this change? If so, I will go ahead to update the > > KIP > > > >> and > > > >> > implement this behavior. > > > >> > > > > >> > Thanks, > > > >> > Dong > > > >> > > > > >> > > > > >> > > > > >> > On Tue, Jan 17, 2017 at 10:18 AM, Dong Lin <lindon...@gmail.com> > > > wrote: > > > >> > > > > >> > > Hey Jun, > > > >> > > > > > >> > > Do you have time to review the KIP again or vote for it? > > > >> > > > > > >> > > Hey Ewen, > > > >> > > > > > >> > > Can you also review the KIP again or vote for it? I have > discussed > > > >> with > > > >> > > Radai and Becket regarding your concern. We still think putting > it > > > in > > > >> > Admin > > > >> > > Client seems more intuitive because there is use-case where > > > >> application > > > >> > > which manages topic or produces data may also want to purge > data. > > It > > > >> > seems > > > >> > > weird if they need to create a consumer to do this. > > > >> > > > > > >> > > Thanks, > > > >> > > Dong > > > >> > > > > > >> > > On Thu, Jan 12, 2017 at 9:34 AM, Mayuresh Gharat < > > > >> > > gharatmayures...@gmail.com> wrote: > > > >> > > > > > >> > >> +1 (non-binding) > > > >> > >> > > > >> > >> Thanks, > > > >> > >> > > > >> > >> Mayuresh > > > >> > >> > > > >> > >> On Wed, Jan 11, 2017 at 1:03 PM, Dong Lin <lindon...@gmail.com > > > > > >> wrote: > > > >> > >> > > > >> > >> > Sorry for the duplicated email. It seems that gmail will put > > the > > > >> > voting > > > >> > >> > email in this thread if I simply replace DISCUSS with VOTE in > > the > > > >> > >> subject. > > > >> > >> > > > > >> > >> > On Wed, Jan 11, 2017 at 12:57 PM, Dong Lin < > > lindon...@gmail.com> > > > >> > wrote: > > > >> > >> > > > > >> > >> > > Hi all, > > > >> > >> > > > > > >> > >> > > It seems that there is no further concern with the KIP-107. > > At > > > >> this > > > >> > >> point > > > >> > >> > > we would like to start the voting process. The KIP can be > > found > > > >> at > > > >> > >> > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-107 > > > >> > >> > > %3A+Add+purgeDataBefore%28%29+API+in+AdminClient. > > > >> > >> > > > > > >> > >> > > Thanks, > > > >> > >> > > Dong > > > >> > >> > > > > > >> > >> > > > > >> > >> > > > >> > >> > > > >> > >> > > > >> > >> -- > > > >> > >> -Regards, > > > >> > >> Mayuresh R. Gharat > > > >> > >> (862) 250-7125 > > > >> > >> > > > >> > > > > > >> > > > > > >> > > > > >> > > > > > > > > > > > > > >
