<< Since we are for the first time defining a bunch of new request formats, I feel it is better to think through the its possible common use cases and try to incorporate them
Agreed.... providing we are only talking about the fields and not the implementation of the functionality. I worry (only a little) about incorporating fields that are not used initially but whole heartily believe doing so will outweigh the pre-optimization criticism because of the requirement to version the protocol (as you brought up). We can then use those fields later without actually implementing the functionality now. ~ Joe Stein - - - - - - - - - - - - - - - - - http://www.stealth.ly - - - - - - - - - - - - - - - - - On Thu, Mar 12, 2015 at 11:08 AM, Guozhang Wang <wangg...@gmail.com> wrote: > The reason I want to bring it up sooner than later is that future changing > a defined request protocol takes quite some effort: we need to bump up the > version of the request, bump up the ZK path data version, and make sure > server can handle old versions as well as new ones both from clients and > from ZK, etc. Since we are for the first time defining a bunch of new > request formats, I feel it is better to think through the its possible > common use cases and try to incorporate them, but I am also fine with > creating another KIP if most people feel it drags too long. > > Guozhang > > On Thu, Mar 12, 2015 at 7:34 AM, Joe Stein <joe.st...@stealth.ly> wrote: > > > Guozhang and Tong, I really do like this idea and where your discussion > > will lead as it will be very useful for folks to have. I am really > > concerned though that we are scope creeping this KIP. > > > > Andrii is already working on following up on ~ 14 different items of > > feedback in regards to the core motivations/scope of the KIP. He has > > uploaded a new patch already and the KIP based on those items and will be > > responding to this thread about that and for what else still requires > > discussion hopefully in the next few hours. > > > > I want to make sure we are focusing on the open items still requiring > > discussion and stabilizing what we have before trying to introducing more > > new features. > > > > Perhaps a new KIP can get added for the new features you are talking > about > > which can reference this and once this is committed that work can begin > for > > folks that are able to contribute to work on it? > > > > ~ Joe Stein > > - - - - - - - - - - - - - - - - - > > > > http://www.stealth.ly > > - - - - - - - - - - - - - - - - - > > > > On Thu, Mar 12, 2015 at 9:51 AM, Tong Li <liton...@us.ibm.com> wrote: > > > > > Guozhang, > > > augmenting topic is fine, but as soon as we start doing that, > other > > > issues follow, for example, access control, who can access the topic, > who > > > can grant permissions. how the information (metadata) itself gets > > secured. > > > Should the information be saved in ZK or a datastore? Will using a > > metadata > > > file causing long term problems such as file updates/synchronization, > > once > > > we have this metadata file, more people will want to put more stuff in > > it. > > > how can we control the format? K-V pair not good for large data set. > > > Clearly there is a need for it, I wonder if we can make this thing > > > plugable and provide a default implementation which allows us try > > different > > > solutions and also allow people to completely ignore it if they do not > > want > > > to deal with any of these. > > > > > > Thanks. > > > > > > Tong Li > > > OpenStack & Kafka Community Development > > > Building 501/B205 > > > liton...@us.ibm.com > > > > > > [image: Inactive hide details for Guozhang Wang ---03/12/2015 09:39:50 > > > AM---Folks, Just want to elaborate a bit more on the > create-topi]Guozhang > > > Wang ---03/12/2015 09:39:50 AM---Folks, Just want to elaborate a bit > more > > > on the create-topic metadata and batching > > > > > > From: Guozhang Wang <wangg...@gmail.com> > > > To: "dev@kafka.apache.org" <dev@kafka.apache.org> > > > Date: 03/12/2015 09:39 AM > > > Subject: Re: [DISCUSS] KIP-4 - Command line and centralized > > > administrative operations > > > ------------------------------ > > > > > > > > > > > > Folks, > > > > > > Just want to elaborate a bit more on the create-topic metadata and > > batching > > > describe-topic based on config / metadata in my previous email as we > work > > > on KAFKA-1694. The main motivation is to have some sort of topic > > management > > > mechanisms, which I think is quite important in a multi-tenant / cloud > > > architecture: today anyone can create topics in a shared Kafka cluster, > > but > > > there is no concept or "ownership" of topics that are created by > > different > > > users. For example, at LinkedIn we basically distinguish topic owners > via > > > some casual topic name prefix, which is a bit awkward and does not fly > as > > > we scale our customers. It would be great to use describe-topics such > as: > > > > > > Describe all topics that is created by me. > > > > > > Describe all topics whose retention time is overriden to X. > > > > > > Describe all topics whose writable group include user Y (this is > related > > to > > > authorization), etc.. > > > > > > One possible way to achieve this is to add a metadata file in the > > > create-topic request, whose value will also be written ZK as we create > > the > > > topic; then describe-topics can choose to batch topics based on 1) name > > > regex, 2) config K-V matching, 3) metadata regex, etc. > > > > > > Thoughts? > > > > > > Guozhang > > > > > > On Thu, Mar 5, 2015 at 4:37 PM, Guozhang Wang <wangg...@gmail.com> > > wrote: > > > > > > > Thanks for the updated wiki. A few comments below: > > > > > > > > 1. Error description in response: I think if some errorCode could > > > indicate > > > > several different error cases then we should really change it to > > multiple > > > > codes. In general the errorCode itself would be precise and > sufficient > > > for > > > > describing the server side errors. > > > > > > > > 2. Describe topic request: it would be great to go beyond just > batching > > > on > > > > topic name regex for this request. For example, a very common use > case > > of > > > > the topic command is to list all topics whose config A's value is B. > > With > > > > topic name regex then we have to first retrieve __all__ topics's > > > > description info and then filter at the client end, which will be a > > huge > > > > burden on ZK. > > > > > > > > 3. Config K-Vs in create topic: this is related to the previous > point; > > > > maybe we can add another metadata K-V or just a metadata string along > > > side > > > > with config K-V in create topic like we did for offset commit > request. > > > This > > > > field can be quite useful in storing information like "owner" of the > > > topic > > > > who issue the create command, etc, which is quite important for a > > > > multi-tenant setting. Then in the describe topic request we can also > > > batch > > > > on regex of the metadata field. > > > > > > > > 4. Today all the admin operations are async in the sense that command > > > will > > > > return once it is written in ZK, and that is why we need extra > > > verification > > > > like testUtil.waitForTopicCreated() / verify partition reassignment > > > > request, etc. With admin requests we could add a flag to enable / > > disable > > > > synchronous requests; when it is turned on, the response will not > > return > > > > until the request has been completed. And for async requests we can > > add a > > > > "token" field in the response, and then only need a general "admin > > > > verification request" with the given token to check if the async > > request > > > > has been completed. > > > > > > > > 5. +1 for extending Metadata request to include controller / > > coordinator > > > > information, and then we can remove the ConsumerMetadata / > > > ClusterMetadata > > > > requests. > > > > > > > > Guozhang > > > > > > > > On Tue, Mar 3, 2015 at 10:23 AM, Joel Koshy <jjkosh...@gmail.com> > > wrote: > > > > > > > >> Thanks for sending that out Joe - I don't think I will be able to > make > > > >> it today, so if notes can be sent out afterward that would be great. > > > >> > > > >> On Mon, Mar 02, 2015 at 09:16:13AM -0800, Gwen Shapira wrote: > > > >> > Thanks for sending this out Joe. Looking forward to chatting with > > > >> everyone :) > > > >> > > > > >> > On Mon, Mar 2, 2015 at 6:46 AM, Joe Stein <joe.st...@stealth.ly> > > > wrote: > > > >> > > Hey, I just sent out a google hangout invite to all pmc, > > committers > > > >> and > > > >> > > everyone I found working on a KIP. If I missed anyone in the > > invite > > > >> please > > > >> > > let me know and can update it, np. > > > >> > > > > > >> > > We should do this every Tuesday @ 2pm Eastern Time. Maybe we can > > get > > > >> INFRA > > > >> > > help to make a google account so we can manage better? > > > >> > > > > > >> > > To discuss > > > >> > > > > > >> > > > > > > https://cwiki.apache.org/confluence/display/KAFKA/Kafka+Improvement+Proposals > > > >> > > in progress and related JIRA that are interdependent and common > > > work. > > > >> > > > > > >> > > ~ Joe Stein > > > >> > > > > > >> > > On Tue, Feb 24, 2015 at 2:59 PM, Jay Kreps <jay.kr...@gmail.com > > > > > >> wrote: > > > >> > > > > > >> > >> Let's stay on Google hangouts that will also record and make > the > > > >> sessions > > > >> > >> available on youtube. > > > >> > >> > > > >> > >> -Jay > > > >> > >> > > > >> > >> On Tue, Feb 24, 2015 at 11:49 AM, Jeff Holoman < > > > >> jholo...@cloudera.com> > > > >> > >> wrote: > > > >> > >> > > > >> > >> > Jay / Joe > > > >> > >> > > > > >> > >> > We're happy to send out a Webex for this purpose. We could > > record > > > >> the > > > >> > >> > sessions if there is interest and publish them out. > > > >> > >> > > > > >> > >> > Thanks > > > >> > >> > > > > >> > >> > Jeff > > > >> > >> > > > > >> > >> > On Tue, Feb 24, 2015 at 11:28 AM, Jay Kreps < > > jay.kr...@gmail.com > > > > > > > >> wrote: > > > >> > >> > > > > >> > >> > > Let's try to get the technical hang-ups sorted out, > though. I > > > >> really > > > >> > >> > think > > > >> > >> > > there is some benefit to live discussion vs writing. I am > > > >> hopeful that > > > >> > >> if > > > >> > >> > > we post instructions and give ourselves a few attempts we > can > > > >> get it > > > >> > >> > > working. > > > >> > >> > > > > > >> > >> > > Tuesday at that time would work for me...any objections? > > > >> > >> > > > > > >> > >> > > -Jay > > > >> > >> > > > > > >> > >> > > On Tue, Feb 24, 2015 at 8:18 AM, Joe Stein < > > > joe.st...@stealth.ly > > > >> > > > > >> > >> wrote: > > > >> > >> > > > > > >> > >> > > > Weekly would be great maybe like every Tuesday ~ 1pm ET / > > > 10am > > > >> PT > > > >> > >> ???? > > > >> > >> > > > > > > >> > >> > > > I don't mind google hangout but there is always some > issue > > or > > > >> > >> whatever > > > >> > >> > so > > > >> > >> > > > we know the apache irc channel works. We can start there > > and > > > >> see how > > > >> > >> it > > > >> > >> > > > goes? We can pull transcripts too and associate to > tickets > > if > > > >> need be > > > >> > >> > > makes > > > >> > >> > > > it helpful for things. > > > >> > >> > > > > > > >> > >> > > > ~ Joestein > > > >> > >> > > > > > > >> > >> > > > On Tue, Feb 24, 2015 at 11:10 AM, Jay Kreps < > > > >> jay.kr...@gmail.com> > > > >> > >> > wrote: > > > >> > >> > > > > > > >> > >> > > > > We'd talked about doing a Google Hangout to chat about > > > this. > > > >> What > > > >> > >> > about > > > >> > >> > > > > generalizing that a little further...I actually think > it > > > >> would be > > > >> > >> > good > > > >> > >> > > > for > > > >> > >> > > > > everyone spending a reasonable chunk of their week on > > Kafka > > > >> stuff > > > >> > >> to > > > >> > >> > > > maybe > > > >> > >> > > > > sync up once a week. I think we could use time to talk > > > >> through > > > >> > >> design > > > >> > >> > > > > stuff, make sure we are on top of code reviews, talk > > > through > > > >> any > > > >> > >> > tricky > > > >> > >> > > > > issues, etc. > > > >> > >> > > > > > > > >> > >> > > > > We can make it publicly available so that any one can > > > follow > > > >> along > > > >> > >> > who > > > >> > >> > > > > likes. > > > >> > >> > > > > > > > >> > >> > > > > Any interest in doing this? If so I'll try to set it up > > > >> starting > > > >> > >> next > > > >> > >> > > > week. > > > >> > >> > > > > > > > >> > >> > > > > -Jay > > > >> > >> > > > > > > > >> > >> > > > > On Tue, Feb 24, 2015 at 3:57 AM, Andrii Biletskyi < > > > >> > >> > > > > andrii.bilets...@stealth.ly> wrote: > > > >> > >> > > > > > > > >> > >> > > > > > Hi all, > > > >> > >> > > > > > > > > >> > >> > > > > > I've updated KIP page, fixed / aligned document > > > structure. > > > >> Also I > > > >> > >> > > added > > > >> > >> > > > > > some > > > >> > >> > > > > > very initial proposal for AdminClient so we have > > > something > > > >> to > > > >> > >> start > > > >> > >> > > > from > > > >> > >> > > > > > while > > > >> > >> > > > > > discussing the KIP. > > > >> > >> > > > > > > > > >> > >> > > > > > > > > >> > >> > > > > > > > > >> > >> > > > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > > >> > >> > > > >> > > > > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-4+-+Command+line+and+centralized+administrative+operations > > > >> > >> > > > > > > > > >> > >> > > > > > Thanks, > > > >> > >> > > > > > Andrii Biletskyi > > > >> > >> > > > > > > > > >> > >> > > > > > On Wed, Feb 18, 2015 at 9:01 PM, Andrii Biletskyi < > > > >> > >> > > > > > andrii.bilets...@stealth.ly> wrote: > > > >> > >> > > > > > > > > >> > >> > > > > > > Jay, > > > >> > >> > > > > > > > > > >> > >> > > > > > > Re error messages: you are right, in most cases > > client > > > >> will > > > >> > >> have > > > >> > >> > > > enough > > > >> > >> > > > > > > context to show descriptive error message. My > concern > > > is > > > >> that > > > >> > >> we > > > >> > >> > > will > > > >> > >> > > > > > have > > > >> > >> > > > > > > to > > > >> > >> > > > > > > add lots of new error codes for each possible > error. > > Of > > > >> course, > > > >> > >> > we > > > >> > >> > > > > could > > > >> > >> > > > > > > reuse > > > >> > >> > > > > > > some of existing like UknownTopicOrPartitionCode, > but > > > we > > > >> will > > > >> > >> > also > > > >> > >> > > > need > > > >> > >> > > > > > to > > > >> > >> > > > > > > add smth like: TopicAlreadyExistsCode, > > > >> TopicConfigInvalid (both > > > >> > >> > for > > > >> > >> > > > > topic > > > >> > >> > > > > > > name and config, and probably user would like to > know > > > >> what > > > >> > >> > exactly > > > >> > >> > > > > > > is wrong in his config), InvalidReplicaAssignment, > > > >> > >> InternalError > > > >> > >> > > > (e.g. > > > >> > >> > > > > > > zookeeper failure) etc. > > > >> > >> > > > > > > And this is only for TopicCommand, we will also > need > > to > > > >> add > > > >> > >> > similar > > > >> > >> > > > > stuff > > > >> > >> > > > > > > for > > > >> > >> > > > > > > ReassignPartitions, PreferredReplica. So we'll end > up > > > >> with a > > > >> > >> > large > > > >> > >> > > > list > > > >> > >> > > > > > of > > > >> > >> > > > > > > error codes, used only in Admin protocol. > > > >> > >> > > > > > > Having said that, I agree my proposal is not > > consistent > > > >> with > > > >> > >> > other > > > >> > >> > > > > cases. > > > >> > >> > > > > > > Maybe we can find better solution or something > > > >> in-between. > > > >> > >> > > > > > > > > > >> > >> > > > > > > Re Hangout chat: I think it is a great idea. This > way > > > we > > > >> can > > > >> > >> move > > > >> > >> > > on > > > >> > >> > > > > > > faster. > > > >> > >> > > > > > > Let's agree somehow on date/time so people can > join. > > > >> Will work > > > >> > >> > for > > > >> > >> > > me > > > >> > >> > > > > > this > > > >> > >> > > > > > > and > > > >> > >> > > > > > > next week almost anytime if agreed in advance. > > > >> > >> > > > > > > > > > >> > >> > > > > > > Thanks, > > > >> > >> > > > > > > Andrii > > > >> > >> > > > > > > > > > >> > >> > > > > > > On Wed, Feb 18, 2015 at 7:09 PM, Jay Kreps < > > > >> > >> jay.kr...@gmail.com> > > > >> > >> > > > > wrote: > > > >> > >> > > > > > > > > > >> > >> > > > > > >> Hey Andrii, > > > >> > >> > > > > > >> > > > >> > >> > > > > > >> Generally we can do good error handling without > > > needing > > > >> custom > > > >> > >> > > > > > server-side > > > >> > >> > > > > > >> messages. I.e. generally the client has the > context > > to > > > >> know > > > >> > >> that > > > >> > >> > > if > > > >> > >> > > > it > > > >> > >> > > > > > got > > > >> > >> > > > > > >> an error that the topic doesn't exist to say > "Topic > > X > > > >> doesn't > > > >> > >> > > exist" > > > >> > >> > > > > > >> rather > > > >> > >> > > > > > >> than "error code 14" (or whatever). Maybe there > are > > > >> specific > > > >> > >> > cases > > > >> > >> > > > > where > > > >> > >> > > > > > >> this is hard? If we want to add server-side error > > > >> messages we > > > >> > >> > > really > > > >> > >> > > > > do > > > >> > >> > > > > > >> need to do this in a consistent way across the > > > protocol. > > > >> > >> > > > > > >> > > > >> > >> > > > > > >> I still have a bunch of open questions here from > my > > > >> previous > > > >> > >> > > list. I > > > >> > >> > > > > > will > > > >> > >> > > > > > >> be out for the next few days for Strata though. > > Maybe > > > >> we could > > > >> > >> > do > > > >> > >> > > a > > > >> > >> > > > > > Google > > > >> > >> > > > > > >> Hangout chat on any open issues some time towards > > the > > > >> end of > > > >> > >> > next > > > >> > >> > > > week > > > >> > >> > > > > > for > > > >> > >> > > > > > >> anyone interested in this ticket? I have a feeling > > > that > > > >> might > > > >> > >> > > > progress > > > >> > >> > > > > > >> things a little faster than email--I think we > could > > > talk > > > >> > >> through > > > >> > >> > > > those > > > >> > >> > > > > > >> issues I brought up fairly quickly... > > > >> > >> > > > > > >> > > > >> > >> > > > > > >> -Jay > > > >> > >> > > > > > >> > > > >> > >> > > > > > >> On Wed, Feb 18, 2015 at 7:27 AM, Andrii Biletskyi > < > > > >> > >> > > > > > >> andrii.bilets...@stealth.ly> wrote: > > > >> > >> > > > > > >> > > > >> > >> > > > > > >> > Hi all, > > > >> > >> > > > > > >> > > > > >> > >> > > > > > >> > I'm trying to address some of the issues which > > were > > > >> > >> mentioned > > > >> > >> > > > > earlier > > > >> > >> > > > > > >> about > > > >> > >> > > > > > >> > Admin RQ/RP format. One of those was about > > batching > > > >> > >> > operations. > > > >> > >> > > > What > > > >> > >> > > > > > if > > > >> > >> > > > > > >> we > > > >> > >> > > > > > >> > follow TopicCommand approach and let people > > specify > > > >> > >> topic-name > > > >> > >> > > by > > > >> > >> > > > > > >> regexp - > > > >> > >> > > > > > >> > would that cover most of the use cases? > > > >> > >> > > > > > >> > > > > >> > >> > > > > > >> > Secondly, is what information should we > generally > > > >> provide in > > > >> > >> > > Admin > > > >> > >> > > > > > >> > responses. > > > >> > >> > > > > > >> > I realize that Admin commands don't imply they > > will > > > >> be used > > > >> > >> > only > > > >> > >> > > > in > > > >> > >> > > > > > CLI > > > >> > >> > > > > > >> > but, > > > >> > >> > > > > > >> > it seems to me, CLI is a very important client > of > > > this > > > >> > >> > feature. > > > >> > >> > > In > > > >> > >> > > > > > this > > > >> > >> > > > > > >> > case, > > > >> > >> > > > > > >> > seems logical, we would like to provide users > with > > > >> rich > > > >> > >> > > experience > > > >> > >> > > > > in > > > >> > >> > > > > > >> terms > > > >> > >> > > > > > >> > of > > > >> > >> > > > > > >> > getting results / errors of the executed > commands. > > > >> Usually > > > >> > >> we > > > >> > >> > > > supply > > > >> > >> > > > > > >> with > > > >> > >> > > > > > >> > responses only errorCode, which looks very > > limiting, > > > >> in case > > > >> > >> > of > > > >> > >> > > > CLI > > > >> > >> > > > > we > > > >> > >> > > > > > >> may > > > >> > >> > > > > > >> > want to print human readable error description. > > > >> > >> > > > > > >> > > > > >> > >> > > > > > >> > So, taking into account previous item about > > > batching, > > > >> what > > > >> > >> do > > > >> > >> > > you > > > >> > >> > > > > > think > > > >> > >> > > > > > >> > about > > > >> > >> > > > > > >> > having smth like: > > > >> > >> > > > > > >> > > > > >> > >> > > > > > >> > ('create' doesn't support regexp) > > > >> > >> > > > > > >> > CreateTopicRequest => TopicName Partitions > > Replicas > > > >> > >> > > > > ReplicaAssignment > > > >> > >> > > > > > >> > [Config] > > > >> > >> > > > > > >> > CreateTopicResponse => ErrorCode > ErrorDescription > > > >> > >> > > > > > >> > ErrorCode => int16 > > > >> > >> > > > > > >> > ErrorDescription => string (empty if > successful) > > > >> > >> > > > > > >> > > > > >> > >> > > > > > >> > AlterTopicRequest -> TopicNameRegexp Partitions > > > >> > >> > > ReplicaAssignment > > > >> > >> > > > > > >> > [AddedConfig] [DeletedConfig] > > > >> > >> > > > > > >> > AlterTopicResponse -> [TopicName ErrorCode > > > >> ErrorDescription] > > > >> > >> > > > > > >> > CommandErrorCode CommandErrorDescription > > > >> > >> > > > > > >> > CommandErrorCode => int16 > > > >> > >> > > > > > >> > CommandErrorDescription => string (nonempty in > > > case > > > >> of > > > >> > >> fatal > > > >> > >> > > > > error, > > > >> > >> > > > > > >> e.g. > > > >> > >> > > > > > >> > we couldn't get topics by regexp) > > > >> > >> > > > > > >> > > > > >> > >> > > > > > >> > DescribeTopicRequest -> TopicNameRegexp > > > >> > >> > > > > > >> > DescribeTopicResponse -> [TopicName > > TopicDescription > > > >> > >> ErrorCode > > > >> > >> > > > > > >> > ErrorDescription] CommandErrorCode > > > >> CommandErrorDescription > > > >> > >> > > > > > >> > > > > >> > >> > > > > > >> > Also, any thoughts about our discussion > regarding > > > >> re-routing > > > >> > >> > > > > facility? > > > >> > >> > > > > > >> In > > > >> > >> > > > > > >> > my > > > >> > >> > > > > > >> > understanding, it is like between augmenting > > > >> > >> > > TopicMetadataRequest > > > >> > >> > > > > > >> > (to include at least controllerId) and > > implementing > > > >> new > > > >> > >> > generic > > > >> > >> > > > > > >> re-routing > > > >> > >> > > > > > >> > facility so sending messages to controller will > be > > > >> handled > > > >> > >> by > > > >> > >> > > it. > > > >> > >> > > > > > >> > > > > >> > >> > > > > > >> > Thanks, > > > >> > >> > > > > > >> > Andrii Biletskyi > > > >> > >> > > > > > >> > > > > >> > >> > > > > > >> > On Mon, Feb 16, 2015 at 5:26 PM, Andrii > Biletskyi > > < > > > >> > >> > > > > > >> > andrii.bilets...@stealth.ly> wrote: > > > >> > >> > > > > > >> > > > > >> > >> > > > > > >> > > @Guozhang: > > > >> > >> > > > > > >> > > Thanks for your comments, I've answered some > of > > > >> those. The > > > >> > >> > > main > > > >> > >> > > > > > thing > > > >> > >> > > > > > >> is > > > >> > >> > > > > > >> > > having merged request for > > > >> create-alter-delete-describe - I > > > >> > >> > > have > > > >> > >> > > > > some > > > >> > >> > > > > > >> > > concerns about this approach. > > > >> > >> > > > > > >> > > > > > >> > >> > > > > > >> > > @*Jay*: > > > >> > >> > > > > > >> > > I see that introduced ClusterMetadaRequest is > > also > > > >> one of > > > >> > >> > the > > > >> > >> > > > > > >> concerns. > > > >> > >> > > > > > >> > We > > > >> > >> > > > > > >> > > can solve it if we implement re-routing > > facility. > > > >> But I > > > >> > >> > agree > > > >> > >> > > > with > > > >> > >> > > > > > >> > > Guozhang - it will make clients' internals a > > > little > > > >> bit > > > >> > >> > easier > > > >> > >> > > > but > > > >> > >> > > > > > >> this > > > >> > >> > > > > > >> > > seems to be a complex logic to implement and > > > >> support then. > > > >> > >> > > > > > Especially > > > >> > >> > > > > > >> for > > > >> > >> > > > > > >> > > Fetch and Produce (even if we add re-routing > > later > > > >> for > > > >> > >> these > > > >> > >> > > > > > >> requests). > > > >> > >> > > > > > >> > > Also people will tend to avoid this re-routing > > > >> facility > > > >> > >> and > > > >> > >> > > hold > > > >> > >> > > > > > local > > > >> > >> > > > > > >> > > cluster cache to ensure their high-priority > > > requests > > > >> > >> (which > > > >> > >> > > some > > > >> > >> > > > > of > > > >> > >> > > > > > >> the > > > >> > >> > > > > > >> > > admin requests are) not sent to some busy > broker > > > >> where > > > >> > >> they > > > >> > >> > > wait > > > >> > >> > > > > to > > > >> > >> > > > > > be > > > >> > >> > > > > > >> > > routed to the correct one. > > > >> > >> > > > > > >> > > As pointed out by Jun here ( > > > >> > >> > > > > > >> > > > > > >> > >> > > > > > >> > > > > >> > >> > > > > > >> > > > >> > >> > > > > > > > > >> > >> > > > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > > >> > >> > > > >> > > > > > > https://issues.apache.org/jira/browse/KAFKA-1772?focusedCommentId=14234530&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14234530 > > > >> > >> > > > > > >> > ) > > > >> > >> > > > > > >> > > to solve the issue we might introduce a > message > > > >> type to > > > >> > >> get > > > >> > >> > > > > cluster > > > >> > >> > > > > > >> > state. > > > >> > >> > > > > > >> > > But I agree we can just update > > > >> TopicMetadataResponse to > > > >> > >> > > include > > > >> > >> > > > > > >> > > controllerId (and probably smth else). > > > >> > >> > > > > > >> > > What are you thougths? > > > >> > >> > > > > > >> > > > > > >> > >> > > > > > >> > > Thanks, > > > >> > >> > > > > > >> > > Andrii > > > >> > >> > > > > > >> > > > > > >> > >> > > > > > >> > > On Thu, Feb 12, 2015 at 8:31 AM, Guozhang > Wang < > > > >> > >> > > > > wangg...@gmail.com> > > > >> > >> > > > > > >> > wrote: > > > >> > >> > > > > > >> > > > > > >> > >> > > > > > >> > >> I think for the topics commands we can > actually > > > >> merge > > > >> > >> > > > > > >> > >> create/alter/delete/describe as one request > > type > > > >> since > > > >> > >> > their > > > >> > >> > > > > > formats > > > >> > >> > > > > > >> are > > > >> > >> > > > > > >> > >> very much similar, and keep list-topics and > > > others > > > >> like > > > >> > >> > > > > > >> > >> partition-reassignment / > > > preferred-leader-election > > > >> as > > > >> > >> > > separate > > > >> > >> > > > > > >> request > > > >> > >> > > > > > >> > >> types, I also left some other comments on the > > RB > > > ( > > > >> > >> > > > > > >> > >> https://reviews.apache.org/r/29301/). > > > >> > >> > > > > > >> > >> > > > >> > >> > > > > > >> > >> On Wed, Feb 11, 2015 at 2:04 PM, Jay Kreps < > > > >> > >> > > > jay.kr...@gmail.com> > > > >> > >> > > > > > >> wrote: > > > >> > >> > > > > > >> > >> > > > >> > >> > > > > > >> > >> > Yeah I totally agree that we don't want to > > just > > > >> have > > > >> > >> one > > > >> > >> > > "do > > > >> > >> > > > > > admin > > > >> > >> > > > > > >> > >> stuff" > > > >> > >> > > > > > >> > >> > command that has the union of all > parameters. > > > >> > >> > > > > > >> > >> > > > > >> > >> > > > > > >> > >> > What I am saying is that command line tools > > are > > > >> one > > > >> > >> > client > > > >> > >> > > of > > > >> > >> > > > > the > > > >> > >> > > > > > >> > >> > administrative apis, but these will be used > > in > > > a > > > >> number > > > >> > >> > of > > > >> > >> > > > > > >> scenarios > > > >> > >> > > > > > >> > so > > > >> > >> > > > > > >> > >> > they should make logical sense even in the > > > >> absence of > > > >> > >> the > > > >> > >> > > > > command > > > >> > >> > > > > > >> line > > > >> > >> > > > > > >> > >> > tool. Hence comments like trying to clarify > > the > > > >> > >> > > relationship > > > >> > >> > > > > > >> between > > > >> > >> > > > > > >> > >> > ClusterMetadata and TopicMetadata...these > > kinds > > > >> of > > > >> > >> things > > > >> > >> > > > > really > > > >> > >> > > > > > >> need > > > >> > >> > > > > > >> > >> to be > > > >> > >> > > > > > >> > >> > thought through. > > > >> > >> > > > > > >> > >> > > > > >> > >> > > > > > >> > >> > Hope that makes sense. > > > >> > >> > > > > > >> > >> > > > > >> > >> > > > > > >> > >> > -Jay > > > >> > >> > > > > > >> > >> > > > > >> > >> > > > > > >> > >> > On Wed, Feb 11, 2015 at 1:41 PM, Andrii > > > >> Biletskyi < > > > >> > >> > > > > > >> > >> > andrii.bilets...@stealth.ly> wrote: > > > >> > >> > > > > > >> > >> > > > > >> > >> > > > > > >> > >> > > Jay, > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > Thanks for answering. You understood > > > >> correctly, most > > > >> > >> of > > > >> > >> > > my > > > >> > >> > > > > > >> comments > > > >> > >> > > > > > >> > >> were > > > >> > >> > > > > > >> > >> > > related to your point 1) - about "well > > > >> thought-out" > > > >> > >> > apis. > > > >> > >> > > > > Also, > > > >> > >> > > > > > >> yes, > > > >> > >> > > > > > >> > >> as I > > > >> > >> > > > > > >> > >> > > understood we would like to introduce a > > > single > > > >> > >> unified > > > >> > >> > > CLI > > > >> > >> > > > > tool > > > >> > >> > > > > > >> with > > > >> > >> > > > > > >> > >> > > centralized server-side request handling > > for > > > >> lots of > > > >> > >> > > > existing > > > >> > >> > > > > > >> ones > > > >> > >> > > > > > >> > >> (incl. > > > >> > >> > > > > > >> > >> > > TopicCommand, CommitOffsetChecker, > > > >> > >> ReassignPartitions, > > > >> > >> > > smth > > > >> > >> > > > > > else > > > >> > >> > > > > > >> if > > > >> > >> > > > > > >> > >> added > > > >> > >> > > > > > >> > >> > > in future). In our previous discussion ( > > > >> > >> > > > > > >> > >> > > > > > >> https://issues.apache.org/jira/browse/KAFKA-1694 > > > ) > > > > > > >> > >> > people > > > >> > >> > > > > said > > > >> > >> > > > > > >> > they'd > > > >> > >> > > > > > >> > >> > > rather > > > >> > >> > > > > > >> > >> > > have a separate message for each command, > > so, > > > >> yes, > > > >> > >> this > > > >> > >> > > > way I > > > >> > >> > > > > > >> came > > > >> > >> > > > > > >> > to > > > >> > >> > > > > > >> > >> 1-1 > > > >> > >> > > > > > >> > >> > > mapping between commands in the tool and > > > >> protocol > > > >> > >> > > > additions. > > > >> > >> > > &g t; > > But > > > > > > >> > >> > > > > > >> I > > > >> > >> > > > > > >> > >> might > > > >> > >> > > > > > >> > >> > be > > > >> > >> > > > > > >> > >> > > wrong. > > > >> > >> > > > > > >> > >> > > At the end I just try to start discussion > > how > > > >> at > > > >> > >> least > > > >> > >> > > > > > generally > > > >> > >> > > > > > >> > this > > > >> > >> > > > > > >> > >> > > protocol should look like. > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > Thanks, > > > >> > >> > > > > > >> > >> > > Andrii > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > On Wed, Feb 11, 2015 at 11:10 PM, Jay > > Kreps < > > > >> > >> > > > > > jay.kr...@gmail.com > > > >> > >> > > > > > >> > > > > >> > >> > > > > > >> > >> wrote: > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > > Hey Andrii, > > > >> > >> > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > To answer your earlier question we just > > > >> really > > > >> > >> can't > > > >> > >> > be > > > >> > >> > > > > > adding > > > >> > >> > > > > > >> any > > > >> > >> > > > > > >> > >> more > > > >> > >> > > > > > >> > >> > > > scala protocol objects. These things > are > > > >> super hard > > > >> > >> > to > > > >> > >> > > > > > maintain > > > >> > >> > > > > > >> > >> because > > > >> > >> > > > > > >> > >> > > > they hand code the byte parsing and > don't > > > >> have good > > > >> > >> > > > > > versioning > > > >> > >> > > > > > >> > >> support. > > > >> > >> > > > > > >> > >> > > > Since we are already planning on > > converting > > > >> we > > > >> > >> > > definitely > > > >> > >> > > > > > don't > > > >> > >> > > > > > >> > >> want to > > > >> > >> > > > > > >> > >> > > add > > > >> > >> > > > > > >> > >> > > > a ton more of these--they are total > tech > > > >> debt. > > > >> > >> > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > What does it mean that the changes are > > > >> isolated > > > >> > >> from > > > >> > >> > > the > > > >> > >> > > > > > >> current > > > >> > >> > > > > > >> > >> code > > > >> > >> > > > > > >> > >> > > base? > > > >> > >> > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > I actually didn't understand the > > remaining > > > >> > >> comments, > > > >> > >> > > > which > > > >> > >> > > > > of > > > >> > >> > > > > > >> the > > > >> > >> > > > > > >> > >> > points > > > >> > >> > > > > > >> > >> > > > are you responding to? > > > >> > >> > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > Maybe one sticking point here is that > it > > > >> seems like > > > >> > >> > you > > > >> > >> > > > > want > > > >> > >> > > > > > to > > > >> > >> > > > > > >> > make > > > >> > >> > > > > > >> > >> > some > > > >> > >> > > > > > >> > >> > > > kind of tool, and you have made a 1-1 > > > mapping > > > >> > >> between > > > >> > >> > > > > > commands > > > >> > >> > > > > > >> you > > > >> > >> > > > > > >> > >> > > imagine > > > >> > >> > > > > > >> > >> > > > in the tool and protocol additions. I > > want > > > >> to make > > > >> > >> > sure > > > >> > >> > > > we > > > >> > >> > > > > > >> don't > > > >> > >> > > > > > >> > do > > > >> > >> > > > > > >> > >> > that. > > > >> > >> > > > > > >> > >> > > > The protocol needs to be really really > > well > > > >> thought > > > >> > >> > out > > > >> > >> > > > > > against > > > >> > >> > > > > > >> > many > > > >> > >> > > > > > >> > >> > use > > > >> > >> > > > > > >> > >> > > > cases so it should make perfect logical > > > >> sense in > > > >> > >> the > > > >> > >> > > > > absence > > > >> > >> > > > > > of > > > >> > >> > > > > > >> > >> knowing > > > >> > >> > > > > > >> > >> > > the > > > >> > >> > > > > > >> > >> > > > command line tool, right? > > > >> > >> > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > -Jay > > > >> > >> > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > On Wed, Feb 11, 2015 at 11:57 AM, > Andrii > > > >> Biletskyi > > > >> > >> < > > > >> > >> > > > > > >> > >> > > > andrii.bilets...@stealth.ly> wrote: > > > >> > >> > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > > Hey Jay, > > > >> > >> > > > > > >> > >> > > > > > > > >> > >> > > > > > >> > >> > > > > I would like to continue this > > discussion > > > >> as it > > > >> > >> seem > > > >> > >> > > > there > > > >> > >> > > > > > is > > > >> > >> > > > > > >> no > > > >> > >> > > > > > >> > >> > > progress > > > >> > >> > > > > > >> > >> > > > > here. > > > >> > >> > > > > > >> > >> > > > > > > > >> > >> > > > > > >> > >> > > > > First of all, could you please > explain > > > >> what did > > > >> > >> you > > > >> > >> > > > mean > > > >> > >> > > > > in > > > >> > >> > > > > > >> 2? > > > >> > >> > > > > > >> > How > > > >> > >> > > > > > >> > >> > > > exactly > > > >> > >> > > > > > >> > >> > > > > are we going to migrate to the new > java > > > >> protocol > > > >> > >> > > > > > definitions. > > > >> > >> > > > > > >> > And > > > >> > >> > > > > > >> > >> why > > > >> > >> > > > > > >> > >> > > > it's > > > >> > >> > > > > > >> > >> > > > > a blocker for centralized CLI? > > > >> > >> > > > > > >> > >> > > > > > > > >> > >> > > > > > >> > >> > > > > I agree with you, this feature > includes > > > >> lots of > > > >> > >> > > stuff, > > > >> > >> > > > > but > > > >> > >> > > > > > >> > >> thankfully > > > >> > >> > > > > > >> > >> > > > > almost all changes are isolated from > > the > > > >> current > > > >> > >> > code > > > >> > >> > > > > base, > > > >> > >> > > > > > >> > >> > > > > so the main thing, I think, we need > to > > > >> agree is > > > >> > >> > RQ/RP > > > >> > >> > > > > > format. > > > >> > >> > > > > > >> > >> > > > > So how can we start discussion about > > the > > > >> concrete > > > >> > >> > > > > messages > > > >> > >> > > > > > >> > format? > > > >> > >> > > > > > >> > >> > > > > Can we take ( > > > >> > >> > > > > > >> > >> > > > > > > > >> > >> > > > > > >> > >> > > > > > > > >> > >> > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > > > >> > >> > > > > > >> > >> > > > >> > >> > > > > > >> > > > > >> > >> > > > > > >> > > > >> > >> > > > > > > > > >> > >> > > > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > > >> > >> > > > >> > > > > > > > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-4+-+Command+line+and+centralized+administrative+operations#KIP-4-Commandlineandcentralizedadministrativeoperations-ProposedRQ/RPFormat > > > > > > >> > >> > > > > > >> > >> > > > > ) > > > >> > >> > > > > > >> > >> > > > > as starting point? > > > >> > >> > > > > > >> > >> > > > > > > > >> > >> > > > > > >> > >> > > > > We had some doubts earlier whether it > > > worth > > > >> > >> > > introducing > > > >> > >> > > > > one > > > >> > >> > > > > > >> > >> generic > > > >> > >> > > > > > >> > >> > > Admin > > > >> > >> > > > > > >> > >> > > > > Request for all commands ( > > > >> > >> > > > > > >> > >> > > > > > > >> https://issues.apache.org/jira/browse/KAFKA-1694 > > > >> > >> > > > > > >> > >> > > > > ) > > > >> > >> > > > > > >> > >> > > > > but then everybody agreed it would be > > > >> better to > > > >> > >> > have > > > >> > >> > > > > > separate > > > >> > >> > > > > > >> > >> message > > > >> > >> > > > > > >> > >> > > for > > > >> > >> > > > > > >> > >> > > > > each admin command. The Request part > is > > > >> really > > > >> > >> > > dictated > > > >> > >> > > > > > from > > > >> > >> > > > > > >> the > > > >> > >> > > > > > >> > >> > > command > > > >> > >> > > > > > >> > >> > > > > (e.g. TopicCommand) arguments itself, > > so > > > >> the > > > >> > >> > proposed > > > >> > >> > > > > > version > > > >> > >> > > > > > >> > >> should > > > >> > >> > > > > > >> > >> > be > > > >> > >> > > > > > >> > >> > > > > fine (let's put aside for now remarks > > > about > > > >> > >> > Optional > > > >> > >> > > > > type, > > > >> > >> > > > > > >> > >> batching, > > > >> > >> > > > > > >> > >> > > > > configs normalization - I agree with > > all > > > of > > > >> > >> them). > > > >> > >> > > > > > >> > >> > > > > So the second part is Response. I see > > > >> there are > > > >> > >> two > > > >> > >> > > > cases > > > >> > >> > > > > > >> here. > > > >> > >> > > > > > >> > >> > > > > a) "Mutate" requests - > > Create/Alter/... ; > > > >> b) > > > >> > >> "Get" > > > >> > >> > > > > > requests - > > > >> > >> > > > > > >> > >> > > > > List/Describe... > > > >> > >> > > > > > >> > >> > > > > > > > >> > >> > > > > > >> > >> > > > > a) should only hold request result > > > >> (regardless > > > >> > >> what > > > >> > >> > > we > > > >> > >> > > > > > decide > > > >> > >> > > > > > >> > >> about > > > >> > >> > > > > > >> > >> > > > > blocking/non-blocking commands > > > execution). > > > >> > >> > > > > > >> > >> > > > > Usually we provide error code in > > response > > > >> but > > > >> > >> since > > > >> > >> > > we > > > >> > >> > > > > will > > > >> > >> > > > > > >> use > > > >> > >> > > > > > >> > >> this > > > >> > >> > > > > > >> > >> > in > > > >> > >> > > > > > >> > >> > > > > interactive shell we need some human > > > >> readable > > > >> > >> error > > > >> > >> > > > > > >> description > > > >> > >> > > > > > >> > - > > > >> > >> > > > > > >> > >> so > > > >> > >> > > > > > >> > >> > I > > > >> > >> > > > > > >> > >> > > > > added errorDesription field where you > > can > > > >> at > > > >> > >> least > > > >> > >> > > > leave > > > >> > >> > > > > > >> > >> > > > > exception.getMessage. > > > >> > >> > > > > > >> > >> > > > > > > > >> > >> > > > > > >> > >> > > > > b) in addition to previous item > message > > > >> should > > > >> > >> hold > > > >> > >> > > > > command > > > >> > >> > > > > > >> > >> specific > > > >> > >> > > > > > >> > >> > > > > response data. We can discuss in > detail > > > >> each of > > > >> > >> > them > > > >> > >> > > > but > > > >> > >> > > > > > >> let's > > > >> > >> > > > > > >> > for > > > >> > >> > > > > > >> > >> > now > > > >> > >> > > > > > >> > >> > > > > agree about the overall pattern. > > > >> > >> > > > > > >> > >> > > > > > > > >> > >> > > > > > >> > >> > > > > Thanks, > > > >> > >> > > > > > >> > >> > > > > Andrii Biletskyi > > > >> > >> > > > > > >> > >> > > > > > > > >> > >> > > > > > >> > >> > > > > On Fri, Jan 23, 2015 at 6:59 AM, Jay > > > Kreps > > > >> < > > > >> > >> > > > > > >> jay.kr...@gmail.com > > > >> > >> > > > > > >> > > > > > >> > >> > > > > > >> > >> > > wrote: > > > >> > >> > > > > > >> > >> > > > > > > > >> > >> > > > > > >> > >> > > > > > Hey Joe, > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > This is great. A few comments on > > KIP-4 > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > 1. This is much needed > functionality, > > > >> but there > > > >> > >> > > are a > > > >> > >> > > > > lot > > > >> > >> > > > > > >> of > > > >> > >> > > > > > >> > >> the so > > > >> > >> > > > > > >> > >> > > > let's > > > >> > >> > > > > > >> > >> > > > > > really think these protocols > through. > > > We > > > >> really > > > >> > >> > > want > > > >> > >> > > > to > > > >> > >> > > > > > >> end up > > > >> > >> > > > > > >> > >> > with a > > > >> > >> > > > > > >> > >> > > > set > > > >> > >> > > > > > >> > >> > > > > > of well thought-out, orthoganol > apis. > > > >> For this > > > >> > >> > > > reason I > > > >> > >> > > > > > >> think > > > >> > >> > > > > > >> > >> it is > > > >> > >> > > > > > >> > >> > > > > really > > > >> > >> > > > > > >> > >> > > > > > important to think through the end > > > state > > > >> even > > > >> > >> if > > > >> > >> > > that > > > >> > >> > > > > > >> includes > > > >> > >> > > > > > >> > >> APIs > > > >> > >> > > > > > >> > >> > > we > > > >> > >> > > > > > >> > >> > > > > > won't implement in the first phase. > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > 2. Let's please please please wait > > > until > > > >> we > > > >> > >> have > > > >> > >> > > > > switched > > > >> > >> > > > > > >> the > > > >> > >> > > > > > >> > >> > server > > > >> > >> > > > > > >> > >> > > > over > > > >> > >> > > > > > >> > >> > > > > > to the new java protocol > definitions. > > > If > > > >> we add > > > >> > >> > > > upteen > > > >> > >> > > > > > >> more ad > > > >> > >> > > > > > >> > >> hoc > > > >> > >> > > > > > >> > >> > > > scala > > > >> > >> > > > > > >> > >> > > > > > objects that is just generating > more > > > >> work for > > > >> > >> the > > > >> > >> > > > > > >> conversion > > > >> > >> > > > > > >> > we > > > >> > >> > > > > > >> > >> > know > > > >> > >> > > > > > >> > >> > > we > > > >> > >> > > > > > >> > >> > > > > > have to do. > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > 3. This proposal introduces a new > > type > > > of > > > >> > >> > optional > > > >> > >> > > > > > >> parameter. > > > >> > >> > > > > > >> > >> This > > > >> > >> > > > > > >> > >> > is > > > >> > >> > > > > > >> > >> > > > > > inconsistent with everything else > in > > > the > > > >> > >> protocol > > > >> > >> > > > where > > > >> > >> > > > > > we > > > >> > >> > > > > > >> use > > > >> > >> > > > > > >> > >> -1 > > > >> > >> > > > > > >> > >> > or > > > >> > >> > > > > > >> > >> > > > some > > > >> > >> > > > > > >> > >> > > > > > other marker value. You could argue > > > >> either way > > > >> > >> > but > > > >> > >> > > > > let's > > > >> > >> > > > > > >> stick > > > >> > >> > > > > > >> > >> with > > > >> > >> > > > > > >> > >> > > > that > > > >> > >> > > > > > >> > >> > > > > > for consistency. For clients that > > > >> implemented > > > >> > >> the > > > >> > >> > > > > > protocol > > > >> > >> > > > > > >> in > > > >> > >> > > > > > >> > a > > > >> > >> > > > > > >> > >> > > better > > > >> > >> > > > > > >> > >> > > > > way > > > >> > >> > > > > > >> > >> > > > > > than our scala code these basic > > > >> primitives are > > > >> > >> > hard > > > >> > >> > > > to > > > >> > >> > > > > > >> change. > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > 4. ClusterMetadata: This seems to > > > >> duplicate > > > >> > >> > > > > > >> > TopicMetadataRequest > > > >> > >> > > > > > >> > >> > > which > > > >> > >> > > > > > >> > >> > > > > has > > > >> > >> > > > > > >> > >> > > > > > brokers, topics, and partitions. I > > > think > > > >> we > > > >> > >> > should > > > >> > >> > > > > rename > > > >> > >> > > > > > >> that > > > >> > >> > > > > > >> > >> > > request > > > >> > >> > > > > > >> > >> > > > > > ClusterMetadataRequest (or just > > > >> > >> MetadataRequest) > > > >> > >> > > and > > > >> > >> > > > > > >> include > > > >> > >> > > > > > >> > >> the id > > > >> > >> > > > > > >> > >> > > of > > > >> > >> > > > > > >> > >> > > > > the > > > >> > >> > > > > > >> > >> > > > > > controller. Or are there other > things > > > we > > > >> could > > > >> > >> > add > > > >> > >> > > > > here? > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > 5. We have a tendency to try to > make > > a > > > >> lot of > > > >> > >> > > > requests > > > >> > >> > > > > > that > > > >> > >> > > > > > >> > can > > > >> > >> > > > > > >> > >> > only > > > >> > >> > > > > > >> > >> > > go > > > >> > >> > > > > > >> > >> > > > > to > > > >> > >> > > > > > >> > >> > > > > > particular nodes. This adds a lot > of > > > >> burden for > > > >> > >> > > > client > > > >> > >> > > > > > >> > >> > > implementations > > > >> > >> > > > > > >> > >> > > > > (it > > > >> > >> > > > > > >> > >> > > > > > sounds easy but each discovery can > > fail > > > >> in many > > > >> > >> > > parts > > > >> > >> > > > > so > > > >> > >> > > > > > it > > > >> > >> > > > > > >> > >> ends up > > > >> > >> > > > > > >> > >> > > > > being a > > > >> > >> > > > > > >> > >> > > > > > full state machine to do right). I > > > think > > > >> we > > > >> > >> > should > > > >> > >> > > > > > consider > > > >> > >> > > > > > >> > >> making > > > >> > >> > > > > > >> > >> > > > admin > > > >> > >> > > > > > >> > >> > > > > > commands and ideally as many of the > > > >> other apis > > > >> > >> as > > > >> > >> > > > > > possible > > > >> > >> > > > > > >> > >> > available > > > >> > >> > > > > > >> > >> > > on > > > >> > >> > > > > > >> > >> > > > > all > > > >> > >> > > > > > >> > >> > > > > > brokers and just redirect to the > > > >> controller on > > > >> > >> > the > > > >> > >> > > > > broker > > > >> > >> > > > > > >> > side. > > > >> > >> > > > > > >> > >> > > Perhaps > > > >> > >> > > > > > >> > >> > > > > > there would be a general way to > > > >> encapsulate > > > >> > >> this > > > >> > >> > > > > > re-routing > > > >> > >> > > > > > >> > >> > behavior. > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > 6. We should probably normalize the > > key > > > >> value > > > >> > >> > pairs > > > >> > >> > > > > used > > > >> > >> > > > > > >> for > > > >> > >> > > > > > >> > >> > configs > > > >> > >> > > > > > >> > >> > > > > rather > > > >> > >> > > > > > >> > >> > > > > > than embedding a new formatting. So > > two > > > >> strings > > > >> > >> > > > rather > > > >> > >> > > > > > than > > > >> > >> > > > > > >> > one > > > >> > >> > > > > > >> > >> > with > > > >> > >> > > > > > >> > >> > > an > > > >> > >> > > > > > >> > >> > > > > > internal equals sign. > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > 7. Is the postcondition of these > APIs > > > >> that the > > > >> > >> > > > command > > > >> > >> > > > > > has > > > >> > >> > > > > > >> > >> begun or > > > >> > >> > > > > > >> > >> > > > that > > > >> > >> > > > > > >> > >> > > > > > the command has been completed? It > > is a > > > >> lot > > > >> > >> more > > > >> > >> > > > usable > > > >> > >> > > > > > if > > > >> > >> > > > > > >> the > > > >> > >> > > > > > >> > >> > > command > > > >> > >> > > > > > >> > >> > > > > has > > > >> > >> > > > > > >> > >> > > > > > been completed so you know that if > > you > > > >> create a > > > >> > >> > > topic > > > >> > >> > > > > and > > > >> > >> > > > > > >> then > > > >> > >> > > > > > >> > >> > > publish > > > >> > >> > > > > > >> > >> > > > to > > > >> > >> > > > > > >> > >> > > > > > it you won't get an exception about > > > >> there being > > > >> > >> > no > > > >> > >> > > > such > > > >> > >> > > > > > >> topic. > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > 8. Describe topic and list topics > > > >> duplicate a > > > >> > >> lot > > > >> > >> > > of > > > >> > >> > > > > > stuff > > > >> > >> > > > > > >> in > > > >> > >> > > > > > >> > >> the > > > >> > >> > > > > > >> > >> > > > > metadata > > > >> > >> > > > > > >> > >> > > > > > request. Is there a reason to give > > back > > > >> topics > > > >> > >> > > marked > > > >> > >> > > > > for > > > >> > >> > > > > > >> > >> > deletion? I > > > >> > >> > > > > > >> > >> > > > > feel > > > >> > >> > > > > > >> > >> > > > > > like if we just make the > > post-condition > > > >> of the > > > >> > >> > > delete > > > >> > >> > > > > > >> command > > > >> > >> > > > > > >> > be > > > >> > >> > > > > > >> > >> > that > > > >> > >> > > > > > >> > >> > > > the > > > >> > >> > > > > > >> > >> > > > > > topic is deleted that will get rid > of > > > >> the need > > > >> > >> > for > > > >> > >> > > > this > > > >> > >> > > > > > >> right? > > > >> > >> > > > > > >> > >> And > > > >> > >> > > > > > >> > >> > it > > > >> > >> > > > > > >> > >> > > > > will > > > >> > >> > > > > > >> > >> > > > > > be much more intuitive. > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > 9. Should we consider batching > these > > > >> requests? > > > >> > >> We > > > >> > >> > > > have > > > >> > >> > > > > > >> > generally > > > >> > >> > > > > > >> > >> > > tried > > > >> > >> > > > > > >> > >> > > > to > > > >> > >> > > > > > >> > >> > > > > > allow multiple operations to be > > > batched. > > > >> My > > > >> > >> > > suspicion > > > >> > >> > > > > is > > > >> > >> > > > > > >> that > > > >> > >> > > > > > >> > >> > without > > > >> > >> > > > > > >> > >> > > > > this > > > >> > >> > > > > > >> > >> > > > > > we will get a lot of code that does > > > >> something > > > >> > >> > like > > > >> > >> > > > > > >> > >> > > > > > for(topic: > > adminClient.listTopics()) > > > >> > >> > > > > > >> > >> > > > > > > > adminClient.describeTopic(topic) > > > >> > >> > > > > > >> > >> > > > > > this code will work great when you > > test > > > >> on 5 > > > >> > >> > topics > > > >> > >> > > > but > > > >> > >> > > > > > >> not do > > > >> > >> > > > > > >> > >> as > > > >> > >> > > > > > >> > >> > > well > > > >> > >> > > > > > >> > >> > > > if > > > >> > >> > > > > > >> > >> > > > > > you have 50k. > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > 10. I think we should also discuss > > how > > > >> we want > > > >> > >> to > > > >> > >> > > > > expose > > > >> > >> > > > > > a > > > >> > >> > > > > > >> > >> > > programmatic > > > >> > >> > > > > > >> > >> > > > > JVM > > > >> > >> > > > > > >> > >> > > > > > client api for these operations. > > > >> Currently > > > >> > >> people > > > >> > >> > > > rely > > > >> > >> > > > > on > > > >> > >> > > > > > >> > >> > AdminUtils > > > >> > >> > > > > > >> > >> > > > > which > > > >> > >> > > > > > >> > >> > > > > > is totally sketchy. I think we > > probably > > > >> need > > > >> > >> > > another > > > >> > >> > > > > > client > > > >> > >> > > > > > >> > >> under > > > >> > >> > > > > > >> > >> > > > > clients/ > > > >> > >> > > > > > >> > >> > > > > > that exposes administrative > > > >> functionality. We > > > >> > >> > will > > > >> > >> > > > need > > > >> > >> > > > > > >> this > > > >> > >> > > > > > >> > >> just > > > >> > >> > > > > > >> > >> > to > > > >> > >> > > > > > >> > >> > > > > > properly test the new apis, I > > suspect. > > > We > > > >> > >> should > > > >> > >> > > > figure > > > >> > >> > > > > > out > > > >> > >> > > > > > >> > that > > > >> > >> > > > > > >> > >> > API. > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > 11. The other information that > would > > be > > > >> really > > > >> > >> > > useful > > > >> > >> > > > > to > > > >> > >> > > > > > >> get > > > >> > >> > > > > > >> > >> would > > > >> > >> > > > > > >> > >> > be > > > >> > >> > > > > > >> > >> > > > > > information about partitions--how > > much > > > >> data is > > > >> > >> in > > > >> > >> > > the > > > >> > >> > > > > > >> > partition, > > > >> > >> > > > > > >> > >> > what > > > >> > >> > > > > > >> > >> > > > are > > > >> > >> > > > > > >> > >> > > > > > the segment offsets, what is the > > > log-end > > > >> offset > > > >> > >> > > (i.e. > > > >> > >> > > > > > last > > > >> > >> > > > > > >> > >> offset), > > > >> > >> > > > > > >> > >> > > > what > > > >> > >> > > > > > >> > >> > > > > is > > > >> > >> > > > > > >> > >> > > > > > the compaction point, etc. I think > > that > > > >> done > > > >> > >> > right > > > >> > >> > > > this > > > >> > >> > > > > > >> would > > > >> > >> > > > > > >> > be > > > >> > >> > > > > > >> > >> > the > > > >> > >> > > > > > >> > >> > > > > > successor to the very awkward > > > >> OffsetRequest we > > > >> > >> > have > > > >> > >> > > > > > today. > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > -Jay > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > On Wed, Jan 21, 2015 at 10:27 PM, > Joe > > > >> Stein < > > > >> > >> > > > > > >> > >> joe.st...@stealth.ly> > > > >> > >> > > > > > >> > >> > > > > wrote: > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > > Hi, created a KIP > > > >> > >> > > > > > >> > >> > > > > > > > > > >> > >> > > > > > >> > >> > > > > > > > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > > > >> > >> > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > > > >> > >> > > > > > >> > >> > > > >> > >> > > > > > >> > > > > >> > >> > > > > > >> > > > >> > >> > > > > > > > > >> > >> > > > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > > >> > >> > > > >> > > > > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-4+-+Command+line+and+centralized+administrative+operations > > > >> > >> > > > > > >> > >> > > > > > > > > > >> > >> > > > > > >> > >> > > > > > > JIRA > > > >> > >> > > > > https://issues.apache.org/jira/browse/KAFKA-1694 > > > >> > >> > > > > > >> > >> > > > > > > > > > >> > >> > > > > > >> > >> > > > > > > > > > >> /******************************************* > > > >> > >> > > > > > >> > >> > > > > > > Joe Stein > > > >> > >> > > > > > >> > >> > > > > > > Founder, Principal Consultant > > > >> > >> > > > > > >> > >> > > > > > > Big Data Open Source Security > LLC > > > >> > >> > > > > > >> > >> > > > > > > http://www.stealth.ly > > > >> > >> > > > > > >> > >> > > > > > > Twitter: @allthingshadoop < > > > >> > >> > > > > > >> > >> > http://www.twitter.com/allthingshadoop > > > >> > >> > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > > > > > > > >> ********************************************/ > > > >> > >> > > > > > >> > >> > > > > > > > > > >> > >> > > > > > >> > >> > > > > > > > > >> > >> > > > > > >> > >> > > > > > > > >> > >> > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > > > >> > >> > > > > > >> > >> > > > >> > >> > > > > > >> > >> > > > >> > >> > > > > > >> > >> > > > >> > >> > > > > > >> > >> -- > > > >> > >> > > > > > >> > >> -- Guozhang > > > >> > >> > > > > > >> > >> > > > >> > >> > > > > > >> > > > > > >> > >> > > > > > >> > > > > > >> > >> > > > > > >> > > > > >> > >> > > > > > >> > > > >> > >> > > > > > > > > > >> > >> > > > > > > > > > >> > >> > > > > > > > > >> > >> > > > > > > > >> > >> > > > > > > >> > >> > > > > > >> > >> > > > > >> > >> > > > > >> > >> > > > > >> > >> > -- > > > >> > >> > Jeff Holoman > > > >> > >> > Systems Engineer > > > >> > >> > > > > >> > >> > > > >> > > > >> > > > > > > > > > > > > -- > > > > -- Guozhang > > > > > > > > > > > > > > > > -- > > > -- Guozhang > > > > > > > > > > > > -- > -- Guozhang >
