On Thu, Dec 21, 2017, at 10:28, Jason Gustafson wrote:
> Hey Matthias,
>
> Let me suggest an alternative. As you have mentioned, these config classes
> do not give users much benefit currently. Maybe we change that? I think
> many users would appreciate having a builder for configuration since it
> provides type safety and is generally a much friendlier pattern to work
> with programmatically. Users could then do something like this:
>
> ConsumerConfig config = ConsumerConfig.newBuilder()
> .setBootstrapServers("localhost:9092")
> .setGroupId("group")
> .setRequestTimeout(15, TimeUnit.SECONDS)
> .build();
>
> Consumer consumer = new KafkaConsumer(config);
>
> An additional benefit of this is that it gives us a better way to expose
> config deprecations. In any case, it would make it less odd to expose the
> public constructor without giving users anything useful to do with the
> class.
Yeah, that would be good. The builder idea would definitely make it a lot
easier to configure clients programmatically.
I do wonder if there are some cross-version compatibility issues here. If
there's any configuration that needs to be set by the client, but then
propagated to the broker to be applied, the validation of that configuration
really needs to be done by the broker itself. The client code doesn't know the
broker version, so it can't validate these configs. One example is topic
configurations (although those are not set by ProducerConfig). I'm not sure
how big of an issue this is with our current configurations.
Another problem here is that all these builder functions become API, and cannot
easily be changed. So if we want to change a configuration key that formerly
accepted an int to accept a long, it will be difficult to do that. We would
have to add a new function with a separate name.
best,
Colin
>
> What do you think?
>
> -Jason
>
> On Wed, Dec 20, 2017 at 5:59 PM, Matthias J. Sax <matth...@confluent.io>
> wrote:
>
> > It's tailored for internal usage. I think client constructors don't
> > benefit from accepting those config objects. We just want to be able to
> > access the default values for certain parameters.
> >
> > From a user point of view, it's actually boiler plate code if you pass
> > in a config object instead of a plain Properties object because the
> > config object itself is immutable.
> >
> > I actually create a JIRA to remove the constructors from KafkaStreams
> > that do accept StreamsConfig for exact this reason:
> > https://issues.apache.org/jira/browse/KAFKA-6386
> >
> >
> > -Matthias
> >
> >
> > On 12/20/17 3:33 PM, Jason Gustafson wrote:
> > > Hi Matthias,
> > >
> > > Isn't it a little weird to make these constructors public but not also
> > > expose the corresponding client constructors that use them?
> > >
> > > -Jason
> > >
> > > On Tue, Dec 19, 2017 at 9:30 AM, Bill Bejeck <bbej...@gmail.com> wrote:
> > >
> > >> +1
> > >>
> > >> On Tue, Dec 19, 2017 at 12:09 PM, Guozhang Wang <wangg...@gmail.com>
> > >> wrote:
> > >>
> > >>> +1
> > >>>
> > >>> On Tue, Dec 19, 2017 at 1:49 AM, Tom Bentley <t.j.bent...@gmail.com>
> > >>> wrote:
> > >>>
> > >>>> +1
> > >>>>
> > >>>> On 18 December 2017 at 23:28, Vahid S Hashemian <
> > >>> vahidhashem...@us.ibm.com
> > >>>>>
> > >>>> wrote:
> > >>>>
> > >>>>> +1
> > >>>>>
> > >>>>> Thanks for the KIP.
> > >>>>>
> > >>>>> --Vahid
> > >>>>>
> > >>>>>
> > >>>>>
> > >>>>> From: Ted Yu <yuzhih...@gmail.com>
> > >>>>> To: dev@kafka.apache.org
> > >>>>> Date: 12/18/2017 02:45 PM
> > >>>>> Subject: Re: [VOTE] KIP-243: Make ProducerConfig and
> > >>>> ConsumerConfig
> > >>>>> constructors public
> > >>>>>
> > >>>>>
> > >>>>>
> > >>>>> +1
> > >>>>>
> > >>>>> nit: via "copy and past" an 'e' is missing at the end.
> > >>>>>
> > >>>>> On Mon, Dec 18, 2017 at 2:38 PM, Matthias J. Sax <
> > >>> matth...@confluent.io>
> > >>>>> wrote:
> > >>>>>
> > >>>>>> Hi,
> > >>>>>>
> > >>>>>> I want to propose the following KIP:
> > >>>>>>
> > >>>>> https://urldefense.proofpoint.com/v2/url?u=https-3A__cwiki.
> > >>>>> apache.org_confluence_display_KAFKA_KIP-2D&d=DwIBaQ&c=jf_
> > >>>>> iaSHvJObTbx-siA1ZOg&r=Q_itwloTQj3_xUKl7Nzswo6KE4Nj-
> > >>>>> kjJc7uSVcviKUc&m=JToRX4-HeVsRoOekIz18ht-YLMe-T21MttZTgbxB4ag&s=
> > >>>>> 6aZjPCc9e00raokVPKvx1BxwDOHyCuKNgtBXPMeoHy4&e=
> > >>>>>
> > >>>>>> 243%3A+Make+ProducerConfig+and+ConsumerConfig+constructors+public
> > >>>>>>
> > >>>>>>
> > >>>>>> This is a rather straight forward change, thus I skip the DISCUSS
> > >>>>>> thread and call for a vote immediately.
> > >>>>>>
> > >>>>>>
> > >>>>>> -Matthias
> > >>>>>>
> > >>>>>>
> > >>>>>
> > >>>>>
> > >>>>>
> > >>>>>
> > >>>>>
> > >>>>
> > >>>
> > >>>
> > >>>
> > >>> --
> > >>> -- Guozhang
> > >>>
> > >>
> > >
> >
> >
