+1 (binding), though I still think the Map should be <String, ?> instead of
<?, ?>.
I also think its better to just expose the defaults as constants on the
class. Apparently there was discussion of this before and the concern is
that people write code that rely on the default configs and we might break
their code if we change it. I don't really buy this as using the constant
allows you to to symbolically reference the value rather than making your
own copy of it. Usually if we change a default like that there is an
important reason why and having the old copied value might be worse than
having the value change out from under you. Having the defaults explicitly
exposed can also be helpful when writing tests sometimes.
-Ewen
On Wed, Jan 3, 2018 at 9:30 AM, Colin McCabe <cmcc...@apache.org> wrote:
> 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
> > > >>>
> > > >>
> > > >
> > >
> > >
>
