Re: [DISCUSS] KIP-4 - Command line and centralized administrative operations

[Jun Rao]

101. There may be a use case where you only want the topics to be created
manually by admins. Currently, you can do that by disabling auto topic
creation and issue topic creation from the TopicCommand. If we disable auto
topic creation completely on the broker and don't have a way to distinguish
between topic creation requests from the regular clients and the admin, we
can't support manual topic creation any more. I was thinking that another
way of distinguishing the clients making the topic creation requests is
using clientId. For example, the admin tool can set it to something like
admin and the broker can treat that clientId specially.

Also, there is a related discussion in KAFKA-2020. Currently, we do the
following in TopicMetadataResponse:

1. If leader is not available, we set the partition level error code to
LeaderNotAvailable.
2. If a non-leader replica is not available, we take that replica out of
the assigned replica list and isr in the response. As an indication for
doing that, we set the partition level error code to ReplicaNotAvailable.

This has a few problems. First, ReplicaNotAvailable probably shouldn't be
an error, at least for the normal producer/consumer clients that just want
to find out the leader. Second, it can happen that both the leader and
another replica are not available at the same time. There is no error code
to indicate both. Third, even if a replica is not available, it's still
useful to return its replica id since some clients (e.g. admin tool) may
still make use of it.

One way to address this issue is to always return the replica id for
leader, assigned replicas, and isr regardless of whether the corresponding
broker is live or not. Since we also return the list of live brokers, the
client can figure out whether a leader or a replica is live or not and act
accordingly. This way, we don't need to set the partition level error code
when the leader or a replica is not available. This doesn't change the wire
protocol, but does change the semantics. Since we are evolving the protocol
of TopicMetadataRequest here, we can potentially piggyback the change.

102.1 For those types of errors due to invalid input, shouldn't we just
guard it at parameter validation time and throw InvalidArgumentException
without even sending the request to the broker?

Thanks,

Jun


On Mon, Mar 16, 2015 at 10:37 AM, Andrii Biletskyi <
andrii.bilets...@stealth.ly> wrote:

> Jun,
>
> Answering your questions:
>
> 101. If I understand you correctly, you are saying future producer versions
> (which
> will be ported to TMR_V1) won't be able to automatically create topic (if
> we
> unconditionally remove topic creation from there). But we need to this
> preserve logic.
> Ok, about your proposal: I'm not a big fan too, when it comes to
> differentiating
> clients directly in protocol schema. And also I'm not sure I understand at
> all why
> auto.create.topics.enable is a server side configuration. Can we deprecate
> this setting
> in future versions, add this setting to producer and based on that upon
> receiving
> UnknownTopic create topic explicitly by a separate producer call via
> adminClient?
>
> 102.1. Hm, yes. It's because we want to support batching and at the same
> time we
> want to give descriptive error messages for clients. Since AdminClient
> holds the context
> to construct such messages (e.g. AdminClient layer can know that
> InvalidArgumentsCode
> means two cases: either invalid number - e.g. -1; or replication-factor was
> provided while
> partitions argument wasn't) - I wrapped responses in Exceptions. But I'm
> open to any
> other ideas, this was just initial version.
> 102.2. Yes, I agree. I'll change that to probably some other dto.
>
> Thanks,
> Andrii Biletskyi
>
> On Fri, Mar 13, 2015 at 7:16 PM, Jun Rao <j...@confluent.io> wrote:
>
> > Andrii,
> >
> > 101. That's what I was thinking too, but it may not be that simple. In
> > TopicMetadataRequest_V1,
> > we can let it not trigger auto topic creation. Then, in the producer
> side,
> > if it gets an UnknownTopicException, it can explicitly issue a
> > createTopicRequest for auto topic creation. On the consumer side, it will
> > never issue createTopicRequest. This works when auto topic creation is
> > enabled on the broker side. However, I am not sure how things will work
> > when auto topic creation is disabled on the broker side. In this case, we
> > want to have a way to manually create a topic, potentially through admin
> > commands. However, then we need a way to distinguish createTopicRequest
> > issued from the producer clients and the admin tools. May be we can add a
> > new field in createTopicRequest and set it differently in the producer
> > client and the admin client. However, I am not sure if that's the best
> > approach.
> >
> > 2. Yes, refactoring existing requests is a non-trivial amount of work. I
> > posted some comments in KAFKA-1927. We will probably have to fix
> KAFKA-1927
> > first, before adding the new logic in KAFKA-1694. Otherwise, the changes
> > will be too big.
> >
> > 102. About the AdminClient:
> > 102.1. It's a bit weird that we return exception in the api. It seems
> that
> > we should either return error code or throw an exception when getting the
> > response state.
> > 102.2. We probably shouldn't explicitly use the request object in the
> api.
> > Not every request evolution requires an api change.
> >
> > Thanks,
> >
> > Jun
> >
> >
> > On Fri, Mar 13, 2015 at 4:08 AM, Andrii Biletskyi <
> > andrii.bilets...@stealth.ly> wrote:
> >
> > > Jun,
> > >
> > > Thanks for you comments. Answers inline:
> > >
> > > 100. There are a few fields such as ReplicaAssignment,
> > > > ReassignPartitionRequest,
> > > > and PartitionsSerialized that are represented as a string, but
> contain
> > > > composite structures in json. Could we flatten them out directly in
> the
> > > > protocol definition as arrays/records?
> > >
> > >
> > > Yes, now with Admin Client this looks a bit weird. My initial
> motivation
> > > was:
> > > ReassignPartitionCommand accepts input in json, we want to remain
> tools'
> > > interfaces unchanged, where possible.
> > > If we port it to deserialized format, in CLI (/tools project) we will
> > have
> > > to add some
> > > json library since /tools is written in java and we'll need to
> > deserialize
> > > json file
> > > provided by a user. Can we quickly agree on what this library should be
> > > (Jackson, GSON, whatever)?
> > >
> > > 101. Does TopicMetadataRequest v1 still trigger auto topic creation?
> This
> > > > will be a bit weird now that we have a separate topic creation api.
> > Have
> > > > you thought about how the new createTopicRequest and
> > TopicMetadataRequest
> > > > v1 will be used in the producer/consumer client, in addition to admin
> > > > tools? For example, ideally, we don't want TopicMetadataRequest from
> > the
> > > > consumer to trigger auto topic creation.
> > >
> > >
> > > I agree, this strange logic should be fixed. I'm not confident in this
> > > Kafka part so
> > > correct me if I'm wrong, but it doesn't look like a hard thing to do, I
> > > think we can
> > > leverage AdminClient for that in Producer and unconditionally remove
> > topic
> > > creation from the TopicMetadataRequest_V1.
> > >
> > > 2. I think Jay meant getting rid of scala classes
> > > > like HeartbeatRequestAndHeader and HeartbeatResponseAndHeader. We did
> > > that
> > > > as a stop-gap thing when adding the new requests for the consumers.
> > > > However, the long term plan is to get rid of all those and just reuse
> > the
> > > > java request/response in the client. Since this KIP proposes to add a
> > > > significant number of new requests, perhaps we should bite the bullet
> > to
> > > > clean up the existing scala requests first before adding new ones?
> > > >
> > >
> > > Yes, looks like I misunderstood the point of ...RequestAndHeader.
> Okay, I
> > > will
> > > rework that. The only thing is that I don't see any example how it was
> > done
> > > for at
> > > least one existing protocol message. Thus, as I understand, I have to
> > think
> > > how we
> > > are going to do it.
> > > Re porting all existing RQ/RP in this patch. Sounds reasonable, but if
> > it's
> > > an *obligatory*
> > > requirement to have Admin KIP done, I'm afraid this can be a serious
> > > blocker for us.
> > > There are 13 protocol messages and all that would require not only unit
> > > tests but quite
> > > intensive manual testing, no? I'm afraid I'm not the right guy to cover
> > > pretty much all
> > > Kafka core internals :). Let me know your thoughts on this item. Btw
> > there
> > > is a ticket to
> > > follow-up this issue (https://issues.apache.org/jira/browse/KAFKA-2006
> ).
> > >
> > > Thanks,
> > > Andrii Biletskyi
> > >
> > >
> > > On Fri, Mar 13, 2015 at 6:40 AM, Jun Rao <j...@confluent.io> wrote:
> > >
> > > > Andrii,
> > > >
> > > >
> > > > A few more comments.
> > > >
> > > > 100. There are a few fields such as ReplicaAssignment,
> > > > ReassignPartitionRequest,
> > > > and PartitionsSerialized that are represented as a string, but
> contain
> > > > composite structures in json. Could we flatten them out directly in
> the
> > > > protocol definition as arrays/records?
> > > >
> > > > 101. Does TopicMetadataRequest v1 still trigger auto topic creation?
> > This
> > > > will be a bit weird now that we have a separate topic creation api.
> > Have
> > > > you thought about how the new createTopicRequest and
> > TopicMetadataRequest
> > > > v1 will be used in the producer/consumer client, in addition to admin
> > > > tools? For example, ideally, we don't want TopicMetadataRequest from
> > the
> > > > consumer to trigger auto topic creation.
> > > >
> > > > 2. I think Jay meant getting rid of scala classes
> > > > like HeartbeatRequestAndHeader and HeartbeatResponseAndHeader. We did
> > > that
> > > > as a stop-gap thing when adding the new requests for the consumers.
> > > > However, the long term plan is to get rid of all those and just reuse
> > the
> > > > java request/response in the client. Since this KIP proposes to add a
> > > > significant number of new requests, perhaps we should bite the bullet
> > to
> > > > clean up the existing scala requests first before adding new ones?
> > > >
> > > > Thanks,
> > > >
> > > > Jun
> > > >
> > > >
> > > >
> > > > On Thu, Mar 12, 2015 at 3:37 PM, Andrii Biletskyi <
> > > > andrii.bilets...@stealth.ly> wrote:
> > > >
> > > > > Hi,
> > > > >
> > > > > As said above - I list again all comments from this thread so we
> > > > > can see what's left and finalize all pending issues.
> > > > >
> > > > > Comments from Jay:
> > > > > 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.
> > > > >
> > > > > A: Definitely behind this. Would appreciate if there are concrete
> > > > comments
> > > > > how this can be improved.
> > > > >
> > > > > 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.
> > > > >
> > > > > A: Fixed in the latest patch - removed scala protocol classes.
> > > > >
> > > > > 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.
> > > > >
> > > > > A: Fixed in the latest patch - removed MaybeOf type and changed
> > > protocol
> > > > > accordingly.
> > > > >
> > > > > 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?
> > > > >
> > > > > A: I agree. Updated the KIP. Let's extends TopicMetadata to
> version 2
> > > and
> > > > > include controller.
> > > > >
> > > > > 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.
> > > > >
> > > > > A: It's a very interesting idea, but seems there are some concerns
> > > about
> > > > > this
> > > > > feature (like performance considerations, how this will complicate
> > > server
> > > > > etc).
> > > > > I believe this shouldn't be a blocker. If this feature is
> implemented
> > > at
> > > > > some
> > > > > point it won't affect Admin changes - at least no changes to public
> > API
> > > > > will be required.
> > > > >
> > > > > 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.
> > > > >
> > > > > A: Fixed in the latest patch - normalized configs and changed
> > protocol
> > > > > accordingly.
> > > > >
> > > > > 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.
> > > > >
> > > > > A: For long running requests (like reassign partitions) - the post
> > > > > condition is
> > > > > command has begun - so we don't block the client. In case of your
> > > > example -
> > > > > topic commands, this will be refactored and topic commands will be
> > > > executed
> > > > > immediately, since the Controller will serve Admin requests
> > > > > (follow-up ticket KAFKA-1777).
> > > > >
> > > > > 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.
> > > > >
> > > > > A: Fixed in the latest patch - removed topics marked for deletion
> in
> > > > > ListTopicsRequest.
> > > > >
> > > > > 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.
> > > > >
> > > > > A: Updated the KIP - please check "Topic Admin Schema" section.
> > > > >
> > > > > 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.
> > > > >
> > > > > A: Updated the KIP - please check "Admin Client" section with an
> > > initial
> > > > > API proposal.
> > > > >
> > > > > 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.
> > > > >
> > > > > A: I removed ConsumerGroupOffsetsRequest in the latest patch. I
> > believe
> > > > > this should
> > > > > be resolved in a separate KIP / jira ticket.
> > > > >
> > > > > 12. 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.
> > > > >
> > > > > A: Updated the KIP - please check "Protocol Errors" section. I
> added
> > > the
> > > > > comprehensive, fine-grained list of error codes.
> > > > >
> > > > > Comments from Guozhang:
> > > > > 13. 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.
> > > > > AND
> > > > > 14. 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.
> > > > >
> > > > > A: As discussed it is very interesting but can be implemented later
> > > after
> > > > > we have some basic functionality there.
> > > > >
> > > > > 15. 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.
> > > > >
> > > > > A: I see your point. My idea was to provide specific
> Verify...Request
> > > per
> > > > > each
> > > > > long running request, where needed. We can do it the way you
> suggest.
> > > The
> > > > > only
> > > > > concern is that introducing a token we again will make schema
> > > "dynamic".
> > > > We
> > > > > wanted
> > > > > to do similar thing introducing single AdminRequest for all topic
> > > > commands
> > > > > but rejected
> > > > > this idea because we wanted to have schema defined. So this is
> more a
> > > > > choice between:
> > > > > a) have fixed schema but introduce each time new Verify...Request
> for
> > > > > long-running requests
> > > > > b) use one request for verification but generalize it with token
> > > > > I'm fine with whatever decision community come to. Just let me know
> > > your
> > > > > thoughts.
> > > > >
> > > > > Comment from Gwen:
> > > > > 16. Specifically for ownership, I think the plan is to add ACL (it
> > > sounds
> > > > > like you are describing ACL) via an external system (Argus,
> Sentry).
> > > > > I remember KIP-11 described this, but I can't find the KIP any
> > longer.
> > > > >
> > > > > A: Okay, no problem. Not sure though how we are going to handle it.
> > > Wait
> > > > > which KIP
> > > > > will be committed first and include changes to TopicMetadata from
> the
> > > > later
> > > > > one?
> > > > > Anyway, I added this note to "Open Questions" section so we don't
> > miss
> > > > this
> > > > > piece.
> > > > >
> > > > > Thanks,
> > > > > Andrii Biletskyi
> > > > >
> > > > > On Fri, Mar 13, 2015 at 12:34 AM, Andrii Biletskyi <
> > > > > andrii.bilets...@stealth.ly> wrote:
> > > > >
> > > > > > Hi all,
> > > > > >
> > > > > > Today I uploaded the patch that covers some of the discussed and
> > > agreed
> > > > > > items:
> > > > > > - removed MaybeOf optional type
> > > > > > - switched to java protocol definitions
> > > > > > - simplified messages (normalized configs, removed topic marked
> for
> > > > > > deletion)
> > > > > >
> > > > > > I also updated the KIP-4 with respective changes and wrote down
> my
> > > > > > proposal for
> > > > > > pending items:
> > > > > > - Batch Admin Operations -> updated Wire Protocol schema proposal
> > > > > > - Remove ClusterMetadata -> changed to extend
> TopicMetadataRequest
> > > > > > - Admin Client -> updated my initial proposal to reflect batching
> > > > > > - Error codes -> proposed fine-grained error code instead of
> > > > > > AdminRequestFailed
> > > > > >
> > > > > > I will also send a separate email to cover all comments from this
> > > > thread.
> > > > > >
> > > > > > Thanks,
> > > > > > Andrii Biletskyi
> > > > > >
> > > > > >
> > > > > > On Thu, Mar 12, 2015 at 9:26 PM, Gwen Shapira <
> > gshap...@cloudera.com
> > > >
> > > > > > wrote:
> > > > > >
> > > > > >> Found KIP-11 (
> > > > > >>
> > > > >
> > > >
> > >
> >
> https://cwiki.apache.org/confluence/display/KAFKA/KIP-11+-+Authorization+Interface
> > > > > >> )
> > > > > >> It actually specifies changes to the Metadata protocol, so
> making
> > > sure
> > > > > >> both KIPs are consistent in this regard will be good.
> > > > > >>
> > > > > >> On Thu, Mar 12, 2015 at 12:21 PM, Gwen Shapira <
> > > gshap...@cloudera.com
> > > > >
> > > > > >> wrote:
> > > > > >> > Specifically for ownership, I think the plan is to add ACL (it
> > > > sounds
> > > > > >> > like you are describing ACL) via an external system (Argus,
> > > Sentry).
> > > > > >> > I remember KIP-11 described this, but I can't find the KIP any
> > > > longer.
> > > > > >> >
> > > > > >> > Regardless, I think KIP-4 focuses on getting information that
> > > > already
> > > > > >> > exists from Kafka brokers, not on adding information that
> > perhaps
> > > > > >> > should exist but doesn't yet?
> > > > > >> >
> > > > > >> > Gwen
> > > > > >> >
> > > > > >> >
> > > > > >> >
> > > > > >> >
> > > > > >> >
> > > > > >> > On Thu, Mar 12, 2015 at 6:37 AM, Guozhang Wang <
> > > wangg...@gmail.com>
> > > > > >> wrote:
> > > > > >> >> 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.
> > > > > >> >>>> > >> > > > > > 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
> > > > > >>
> > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
>