On Tue, Dec 12, 2017, at 09:39, Jason Gustafson wrote:
> Hi Colin,
>
> They do share the same namespace. We have a "protocol type" field in the
> JoinGroup request to make sure that all members are of the same kind.
Hi Jason,
Thanks. That makes sense.
> Very roughly what I was thinking is something like this. First we introduce an
> interface for deserialization:
>
> interface GroupMetadataDeserializer<Metadata, Assignment> {
> String protocolType();
> Metadata desrializeMetadata(ByteBuffer);
> Assignment deserializeAssignment(ByteBuffer);
> }
>
> Then we add some kind of generic container:
>
> class MemberMetadata<Metadata, Assignment> {
> Metadata metadata;
> Assignment assignment;
> }
>
> Then we have two APIs: one generic and one specific to consumer groups:
>
> <M, A> Map<String, MemberMetadata<M,A>> describeGroup(String groupId,
> GroupMetadataDeserializer<M, A> deserializer);
>
> Map<String, ConsumerGroupMetadata> describeConsumerGroup(String groupId);
>
> (This is just a sketch, so obviously we can change them to use futures or
> to batch or whatever.)
>
> I think it would be fine to not provide a connect-specific API since this
> usage will probably be limited to Connect itself.
Yeah, it probably makes sense to have a separation between describeGroup
and describeConsumerGroup.
We will have to be pretty careful with cross-version compatibility in
describeConsumerGroup. It should be possible for an old client to talk
to a new broker, and a new client to talk to an old broker. So we
should be prepared to read data in multiple formats.
I'm not sure if we need to have a 'deserializer' argument to
describeGroup. We can just let them access a byte array, right?
Theoretically they might also just want to check for the presence or
absence of a group, but not deserialize anything.
best,
Colin
>
> Thanks,
> Jason
>
>
> On Mon, Dec 11, 2017 at 9:15 PM, Colin McCabe <cmcc...@apache.org> wrote:
>
> > Sorry... this is probably a silly question, but do Kafka Connect groups
> > share a namespace with consumer groups? If we had a separate API for
> > Kafka Connect groups vs. Consumer groups, would that make sense? Or
> > should we unify them?
> >
> > best,
> > Colin
> >
> >
> > On Mon, Dec 11, 2017, at 16:11, Jason Gustafson wrote:
> > > Hi Jorge,
> > >
> > > Kafka group management is actually more general than consumer groups
> > > (e.g.
> > > there are kafka connect groups). If we are adding these APIs, I would
> > > suggest we consider the more general protocol and how to expose
> > > group-protocol-specific metadata. For example, it might be reasonable to
> > > have both an API to access to the low-level bytes as well as some
> > > higher-level convenience APIs for accessing consumer groups.
> > >
> > > Thanks,
> > > Jason
> > >
> > > On Mon, Dec 4, 2017 at 4:07 PM, Matthias J. Sax <matth...@confluent.io>
> > > wrote:
> > >
> > > > Jorge,
> > > >
> > > > is there any update regarding this KIP?
> > > >
> > > >
> > > > -Matthias
> > > >
> > > > On 11/17/17 9:14 AM, Guozhang Wang wrote:
> > > > > Hello Jorge,
> > > > >
> > > > > I made a pass over the wiki, and here are a few comments:
> > > > >
> > > > > 1. First, regarding to Tom's comment #2 above, I think if we are only
> > > > going
> > > > > to include the String groupId. Then it is Okay to keep as a String
> > than
> > > > > using a new wrapper class. However, I think we could include the
> > > > > protocol_type returned from the ListGroupsResponse along with the
> > > > groupId.
> > > > > This is a very useful information to tell which consumer groups are
> > from
> > > > > Connect, which ones are from Streams, which ones are user-customized
> > etc.
> > > > > With this, it is reasonable to keep a wrapper class.
> > > > >
> > > > > 2. In ConsumerDescription, could we also add the state, protocol_type
> > > > > (these two are form DescribeGroupResponse), and the Node coordinator
> > > > (this
> > > > > may be returned from the AdminClient itself) as well? This is also
> > for
> > > > > information consistency with the old client (note that protocol_type
> > was
> > > > > called assignment_strategy there).
> > > > >
> > > > > 3. With 1) / 2) above, maybe we can rename "ConsumerGroupListing" to
> > > > > "ConsumerGroupSummary" and make "ConsumerGroupDescription" an
> > extended
> > > > > class of the former with the additional fields?
> > > > >
> > > > >
> > > > >
> > > > > Guozhang
> > > > >
> > > > >
> > > > > On Tue, Nov 7, 2017 at 2:13 AM, Jorge Esteban Quilcate Otoya <
> > > > > quilcate.jo...@gmail.com> wrote:
> > > > >
> > > > >> Hi Tom,
> > > > >>
> > > > >> 1. You're right. I've updated the KIP accordingly.
> > > > >> 2. Yes, I have add it to keep consistency, but I'd like to know what
> > > > others
> > > > >> think about this too.
> > > > >>
> > > > >> Cheers,
> > > > >> Jorge.
> > > > >>
> > > > >> El mar., 7 nov. 2017 a las 9:29, Tom Bentley (<
> > t.j.bent...@gmail.com>)
> > > > >> escribió:
> > > > >>
> > > > >>> Hi again Jorge,
> > > > >>>
> > > > >>> A couple of minor points:
> > > > >>>
> > > > >>> 1. ConsumerGroupDescription has the member `name`, but everywhere
> > else
> > > > >> that
> > > > >>> I've seen the term "group id" is used, so perhaps calling it "id"
> > or
> > > > >>> "groupId" would be more consistent.
> > > > >>> 2. I think you've added ConsumerGroupListing for consistency with
> > > > >>> TopicListing. For topics it makes sense because at well as the name
> > > > there
> > > > >>> is whether the topic is internal. For consumer groups, though
> > there is
> > > > >> just
> > > > >>> the name and having a separate ConsumerGroupListing seems like it
> > > > doesn't
> > > > >>> add very much, and would mostly get in the way when using the API.
> > I
> > > > >> would
> > > > >>> be interested in what others thought about this.
> > > > >>>
> > > > >>> Cheers,
> > > > >>>
> > > > >>> Tom
> > > > >>>
> > > > >>> On 6 November 2017 at 22:16, Jorge Esteban Quilcate Otoya <
> > > > >>> quilcate.jo...@gmail.com> wrote:
> > > > >>>
> > > > >>>> Thanks for the feedback!
> > > > >>>>
> > > > >>>> @Ted Yu: Links added.
> > > > >>>>
> > > > >>>> KIP updated. Changes:
> > > > >>>>
> > > > >>>> * `#listConsumerGroups(ListConsumerGroupsOptions options)` added
> > to
> > > > >> the
> > > > >>>> API.
> > > > >>>> * `DescribeConsumerGroupResult` and `ConsumerGroupDescription`
> > classes
> > > > >>>> described.
> > > > >>>>
> > > > >>>> Cheers,
> > > > >>>> Jorge.
> > > > >>>>
> > > > >>>>
> > > > >>>>
> > > > >>>>
> > > > >>>> El lun., 6 nov. 2017 a las 20:28, Guozhang Wang (<
> > wangg...@gmail.com
> > > > >)
> > > > >>>> escribió:
> > > > >>>>
> > > > >>>>> Hi Matthias,
> > > > >>>>>
> > > > >>>>> You meant "list groups" I think?
> > > > >>>>>
> > > > >>>>> Guozhang
> > > > >>>>>
> > > > >>>>> On Mon, Nov 6, 2017 at 11:17 AM, Matthias J. Sax <
> > > > >>> matth...@confluent.io>
> > > > >>>>> wrote:
> > > > >>>>>
> > > > >>>>>> The main goal of this KIP is to enable decoupling
> > StreamsResetter
> > > > >>> from
> > > > >>>>>> core module. For this case (ie, using AdminClient within
> > > > >>>>>> StreamsResetter) we get the group.id from the user as command
> > line
> > > > >>>>>> argument. Thus, I think the KIP is useful without "describe
> > group"
> > > > >>>>>> command to.
> > > > >>>>>>
> > > > >>>>>> I am happy to include "describe group" command in the KIP. Just
> > > > >> want
> > > > >>> to
> > > > >>>>>> point out, that there is no reason to insist on it IMHO.
> > > > >>>>>>
> > > > >>>>>>
> > > > >>>>>> -Matthias
> > > > >>>>>>
> > > > >>>>>> On 11/6/17 7:06 PM, Guozhang Wang wrote:
> > > > >>>>>>> A quick question: I think we do not yet have the `list consumer
> > > > >>>> groups`
> > > > >>>>>>> func as in the old AdminClient. Without this `describe group`
> > > > >> given
> > > > >>>> the
> > > > >>>>>>> group id would not be very useful. Could you include this as
> > well
> > > > >>> in
> > > > >>>>> your
> > > > >>>>>>> KIP? More specifically, you can look at
> > > > >> kafka.admin.AdminClientfor
> > > > >>>> more
> > > > >>>>>>> details on the APIs.
> > > > >>>>>>>
> > > > >>>>>>>
> > > > >>>>>>> Guozhang
> > > > >>>>>>>
> > > > >>>>>>> On Mon, Nov 6, 2017 at 7:22 AM, Ted Yu <yuzhih...@gmail.com>
> > > > >>> wrote:
> > > > >>>>>>>
> > > > >>>>>>>> Please fill out Discussion thread and JIRA fields.
> > > > >>>>>>>>
> > > > >>>>>>>> Thanks
> > > > >>>>>>>>
> > > > >>>>>>>> On Mon, Nov 6, 2017 at 2:02 AM, Tom Bentley <
> > > > >>> t.j.bent...@gmail.com>
> > > > >>>>>> wrote:
> > > > >>>>>>>>
> > > > >>>>>>>>> Hi Jorge,
> > > > >>>>>>>>>
> > > > >>>>>>>>> Thanks for the KIP. A few initial comments:
> > > > >>>>>>>>>
> > > > >>>>>>>>> 1. The AdminClient doesn't have any API like
> > > > >>> `listConsumerGroups()`
> > > > >>>>>>>>> currently, so in general how does a client know the group ids
> > > > >> it
> > > > >>> is
> > > > >>>>>>>>> interested in?
> > > > >>>>>>>>> 2. Could you fill in the API of DescribeConsumerGroupResult,
> > > > >> just
> > > > >>>> so
> > > > >>>>>>>>> everyone knows exactly what being proposed.
> > > > >>>>>>>>> 3. Can you describe the ConsumerGroupDescription class?
> > > > >>>>>>>>> 4. Probably worth mentioning that this will use
> > > > >>>>>>>>> DescribeGroupsRequest/Response, and also enumerating the
> > error
> > > > >>>> codes
> > > > >>>>>>>> that
> > > > >>>>>>>>> can return (or, equivalently, enumerate the exceptions throw
> > > > >> from
> > > > >>>> the
> > > > >>>>>>>>> futures obtained from the DescribeConsumerGroupResult).
> > > > >>>>>>>>>
> > > > >>>>>>>>> Cheers,
> > > > >>>>>>>>>
> > > > >>>>>>>>> Tom
> > > > >>>>>>>>>
> > > > >>>>>>>>> On 6 November 2017 at 08:19, Jorge Esteban Quilcate Otoya <
> > > > >>>>>>>>> quilcate.jo...@gmail.com> wrote:
> > > > >>>>>>>>>
> > > > >>>>>>>>>> Hi everyone,
> > > > >>>>>>>>>>
> > > > >>>>>>>>>> I would like to start a discussion on KIP-222 [1] based on
> > > > >> issue
> > > > >>>>> [2].
> > > > >>>>>>>>>>
> > > > >>>>>>>>>> Looking forward to feedback.
> > > > >>>>>>>>>>
> > > > >>>>>>>>>> [1]
> > > > >>>>>>>>>> https://cwiki.apache.org/confluence/pages/viewpage.
> > > > >>>>>>>>> action?pageId=74686265
> > > > >>>>>>>>>> [2] https://issues.apache.org/jira/browse/KAFKA-6058
> > > > >>>>>>>>>>
> > > > >>>>>>>>>> Cheers,
> > > > >>>>>>>>>> Jorge.
> > > > >>>>>>>>>>
> > > > >>>>>>>>>
> > > > >>>>>>>>
> > > > >>>>>>>
> > > > >>>>>>>
> > > > >>>>>>>
> > > > >>>>>>
> > > > >>>>>>
> > > > >>>>>
> > > > >>>>>
> > > > >>>>> --
> > > > >>>>> -- Guozhang
> > > > >>>>>
> > > > >>>>
> > > > >>>
> > > > >>
> > > > >
> > > > >
> > > > >
> > > >
> > > >
> >
