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Posted to dev@kafka.apache.org by Scott Carey <sc...@richrelevance.com> on 2013/04/05 22:10:05 UTC
Kafka and Scala versions
Kafka 0.8 and trunk by default have SBT set up to cross-compile 2.8.0,
2.8.2, 2.9.1 and 2.9.2, and it defaults to 2.8.0.
I assume that one of the major contributors requires 2.8.0. Any
approximation on how long will that last?
Dropping 2.8.0 would be beneficial because some uses of Java Conversions
is replaced with Java Converters (in 2.10 +), and Java Converters was not
added until 2.8.1.
http://stackoverflow.com/questions/8301947/what-is-the-difference-between-j
avaconverters-and-javaconversions-in-scala
https://issues.apache.org/jira/browse/KAFKA-717 is attempting to add build
support for Scala 2.10. The required changes to support 2.10 use Java
Converters, which is not available in 2.8.0.
The other item required to support Scala 2.10 is to move from
scala.StaticAnnotation to scala.annotation.StaticAnnotation.
Scala 2.10.x has only scala.annotation.StaticAnnotation.
Scala 2.9.x has both scala.StaticAnnotation (deprecated) and
scala.annotation.StaticAnnotation.
Scala 2.8.x has only scala.StaticAnnotation
Dropping support for 2.8.x entirely and supporting only 2.9.x and 2.10.x
would make 2.10.x support easy.
If 2.8.2 is required (but not 2.8.0), then some sort of conditional
compile or two flavors of the source code where
scala.annotation.StaticAnnotation is used will be required. Use of
StaticAnnotation is very limited.
If 2.8.0 must be kept, then two versions of all code that uses Java
Conversions APIs will also need to be maintained.
I can't find any discussions about 2.8.0 usage requirements. I also don't
know enough about sbt to configure cross compilation to use different
source files for different cases, which would solve the problems above but
add some maintenance burden.
Re: Kafka and Scala versions
Posted by Jun Rao <ju...@gmail.com>.
Ok. Thanks. We will look into upgrading to 2.8.2 post 0.8.
Jun
On Mon, Apr 8, 2013 at 2:08 PM, Scott Carey <sc...@richrelevance.com> wrote:
> We are on 2.10 already.
>
> String interpolation (2.10), Value classes (2.10), parallel collections
> (2.9), are too good to give up. Akka actors, futures, and promises being
> part of the distribution are nice as well.
>
> The compiler is faster, and emits a lot of warnings in Kafka code that
> could be bugs in Kafka.
>
> Upgrading to 2.8.2 significantly simplifies the ability to cross-compile
> with 2.10 (only one small file needs to have a version that differs,
> instead of ~1500 lines). See my recent patches in KAFKA-717.
>
>
> On 4/7/13 10:17 PM, "Jun Rao" <ju...@gmail.com> wrote:
>
> >Scott,
> >
> >Yes, we are still using scala 2.8.0 at LinkedIn. We do plan to upgrade to
> >a
> >later version of scala at some point. However, this may take some time
> >since we will need to upgrade other scala projects at LinkedIn at the same
> >time.
> >
> >It's unfortunate that code change is needed in order to support scala
> >2.10.
> >What are the things that you are looking for in scala 2.10?
> >
> >Thanks,
> >
> >Jun
> >
> >
> >On Fri, Apr 5, 2013 at 1:10 PM, Scott Carey <sc...@richrelevance.com>
> >wrote:
> >
> >> Kafka 0.8 and trunk by default have SBT set up to cross-compile 2.8.0,
> >> 2.8.2, 2.9.1 and 2.9.2, and it defaults to 2.8.0.
> >>
> >> I assume that one of the major contributors requires 2.8.0. Any
> >> approximation on how long will that last?
> >> Dropping 2.8.0 would be beneficial because some uses of Java Conversions
> >> is replaced with Java Converters (in 2.10 +), and Java Converters was
> >>not
> >> added until 2.8.1.
> >>
> >>
> http://stackoverflow.com/questions/8301947/what-is-the-difference-between
> >>-j
> >> avaconverters-and-javaconversions-in-scala
> >>
> >> https://issues.apache.org/jira/browse/KAFKA-717 is attempting to add
> >>build
> >> support for Scala 2.10. The required changes to support 2.10 use Java
> >> Converters, which is not available in 2.8.0.
> >>
> >> The other item required to support Scala 2.10 is to move from
> >> scala.StaticAnnotation to scala.annotation.StaticAnnotation.
> >> Scala 2.10.x has only scala.annotation.StaticAnnotation.
> >> Scala 2.9.x has both scala.StaticAnnotation (deprecated) and
> >> scala.annotation.StaticAnnotation.
> >> Scala 2.8.x has only scala.StaticAnnotation
> >>
> >> Dropping support for 2.8.x entirely and supporting only 2.9.x and 2.10.x
> >> would make 2.10.x support easy.
> >> If 2.8.2 is required (but not 2.8.0), then some sort of conditional
> >> compile or two flavors of the source code where
> >> scala.annotation.StaticAnnotation is used will be required. Use of
> >> StaticAnnotation is very limited.
> >> If 2.8.0 must be kept, then two versions of all code that uses Java
> >> Conversions APIs will also need to be maintained.
> >>
> >> I can't find any discussions about 2.8.0 usage requirements. I also
> >>don't
> >> know enough about sbt to configure cross compilation to use different
> >> source files for different cases, which would solve the problems above
> >>but
> >> add some maintenance burden.
> >>
> >>
> >>
>
>
Re: Kafka and Scala versions
Posted by Scott Carey <sc...@richrelevance.com>.
We are on 2.10 already.
String interpolation (2.10), Value classes (2.10), parallel collections
(2.9), are too good to give up. Akka actors, futures, and promises being
part of the distribution are nice as well.
The compiler is faster, and emits a lot of warnings in Kafka code that
could be bugs in Kafka.
Upgrading to 2.8.2 significantly simplifies the ability to cross-compile
with 2.10 (only one small file needs to have a version that differs,
instead of ~1500 lines). See my recent patches in KAFKA-717.
On 4/7/13 10:17 PM, "Jun Rao" <ju...@gmail.com> wrote:
>Scott,
>
>Yes, we are still using scala 2.8.0 at LinkedIn. We do plan to upgrade to
>a
>later version of scala at some point. However, this may take some time
>since we will need to upgrade other scala projects at LinkedIn at the same
>time.
>
>It's unfortunate that code change is needed in order to support scala
>2.10.
>What are the things that you are looking for in scala 2.10?
>
>Thanks,
>
>Jun
>
>
>On Fri, Apr 5, 2013 at 1:10 PM, Scott Carey <sc...@richrelevance.com>
>wrote:
>
>> Kafka 0.8 and trunk by default have SBT set up to cross-compile 2.8.0,
>> 2.8.2, 2.9.1 and 2.9.2, and it defaults to 2.8.0.
>>
>> I assume that one of the major contributors requires 2.8.0. Any
>> approximation on how long will that last?
>> Dropping 2.8.0 would be beneficial because some uses of Java Conversions
>> is replaced with Java Converters (in 2.10 +), and Java Converters was
>>not
>> added until 2.8.1.
>>
>>http://stackoverflow.com/questions/8301947/what-is-the-difference-between
>>-j
>> avaconverters-and-javaconversions-in-scala
>>
>> https://issues.apache.org/jira/browse/KAFKA-717 is attempting to add
>>build
>> support for Scala 2.10. The required changes to support 2.10 use Java
>> Converters, which is not available in 2.8.0.
>>
>> The other item required to support Scala 2.10 is to move from
>> scala.StaticAnnotation to scala.annotation.StaticAnnotation.
>> Scala 2.10.x has only scala.annotation.StaticAnnotation.
>> Scala 2.9.x has both scala.StaticAnnotation (deprecated) and
>> scala.annotation.StaticAnnotation.
>> Scala 2.8.x has only scala.StaticAnnotation
>>
>> Dropping support for 2.8.x entirely and supporting only 2.9.x and 2.10.x
>> would make 2.10.x support easy.
>> If 2.8.2 is required (but not 2.8.0), then some sort of conditional
>> compile or two flavors of the source code where
>> scala.annotation.StaticAnnotation is used will be required. Use of
>> StaticAnnotation is very limited.
>> If 2.8.0 must be kept, then two versions of all code that uses Java
>> Conversions APIs will also need to be maintained.
>>
>> I can't find any discussions about 2.8.0 usage requirements. I also
>>don't
>> know enough about sbt to configure cross compilation to use different
>> source files for different cases, which would solve the problems above
>>but
>> add some maintenance burden.
>>
>>
>>
Re: Kafka and Scala versions
Posted by Jun Rao <ju...@gmail.com>.
Scott,
Yes, we are still using scala 2.8.0 at LinkedIn. We do plan to upgrade to a
later version of scala at some point. However, this may take some time
since we will need to upgrade other scala projects at LinkedIn at the same
time.
It's unfortunate that code change is needed in order to support scala 2.10.
What are the things that you are looking for in scala 2.10?
Thanks,
Jun
On Fri, Apr 5, 2013 at 1:10 PM, Scott Carey <sc...@richrelevance.com> wrote:
> Kafka 0.8 and trunk by default have SBT set up to cross-compile 2.8.0,
> 2.8.2, 2.9.1 and 2.9.2, and it defaults to 2.8.0.
>
> I assume that one of the major contributors requires 2.8.0. Any
> approximation on how long will that last?
> Dropping 2.8.0 would be beneficial because some uses of Java Conversions
> is replaced with Java Converters (in 2.10 +), and Java Converters was not
> added until 2.8.1.
> http://stackoverflow.com/questions/8301947/what-is-the-difference-between-j
> avaconverters-and-javaconversions-in-scala
>
> https://issues.apache.org/jira/browse/KAFKA-717 is attempting to add build
> support for Scala 2.10. The required changes to support 2.10 use Java
> Converters, which is not available in 2.8.0.
>
> The other item required to support Scala 2.10 is to move from
> scala.StaticAnnotation to scala.annotation.StaticAnnotation.
> Scala 2.10.x has only scala.annotation.StaticAnnotation.
> Scala 2.9.x has both scala.StaticAnnotation (deprecated) and
> scala.annotation.StaticAnnotation.
> Scala 2.8.x has only scala.StaticAnnotation
>
> Dropping support for 2.8.x entirely and supporting only 2.9.x and 2.10.x
> would make 2.10.x support easy.
> If 2.8.2 is required (but not 2.8.0), then some sort of conditional
> compile or two flavors of the source code where
> scala.annotation.StaticAnnotation is used will be required. Use of
> StaticAnnotation is very limited.
> If 2.8.0 must be kept, then two versions of all code that uses Java
> Conversions APIs will also need to be maintained.
>
> I can't find any discussions about 2.8.0 usage requirements. I also don't
> know enough about sbt to configure cross compilation to use different
> source files for different cases, which would solve the problems above but
> add some maintenance burden.
>
>
>