That would mean to have "flink-java_2.10" and "flink-java_2.11" artifacts (and others that depend on flink-java and have no other Scala dependency) in the 0.10.0 release and only "flink-java" in the next 1.0 release.
Do we want that? 2015-11-02 11:37 GMT+01:00 Maximilian Michels <m...@apache.org>: > I'm for leaving it as-is and renaming all artifacts which depend on > Scala for the release following 0.10. > > On Mon, Nov 2, 2015 at 11:32 AM, Fabian Hueske <fhue...@gmail.com> wrote: > > OK, let me try to summarize the discussion (and please correct me if I > got > > something wrong). > > > > 1) Flink deploys Scala 2.11 snapshot artifacts. Therefore, we have to > > release 2.11 artifacts for the 0.10.0 release version as well. > > > > 2) Everybody agrees to appropriately tag all artifacts that have a > > (transitive) Scala dependency. ATM, that would also include flink-java > > which is a bit awkward. The Scala dependency in flink-java originates > from > > the Chill library which is used to obtain a Kryo serializer which is > > initialized with serializers for Scala classes. We could resolve this > issue > > by providing Java and Scala specific implementations of the Kryo > > serializers and have KryoTypeInfos for Java and Scala. > > > > The question to answer right now is, do we want to have "correctly" > labeled > > artifacts for the next 0.10.0 release or do we defer that for 1.0? > > If we want to solve it for 0.10.0 we need to cancel the current RC and > > provide a fix to remove the Scala dependency in flink-java, IMO. > > > > Opinions? > > > > Cheers, Fabian > > > > 2015-11-02 8:55 GMT+01:00 Stephan Ewen <se...@apache.org>: > > > >> +1 for the approach discusses here, and for removing Scala dependencies > >> from modules that can be Scala independent. > >> > >> It would be nice if pure Java users would not see any Scala versioning > (on > >> flink-core, flink-java, later also flink-sreaming-java). I guess for any > >> runtime-related parts (including flink-client and currently all > streaming > >> projects), we need the Scala versions... > >> > >> On Sun, Nov 1, 2015 at 9:29 AM, Maximilian Michels <m...@apache.org> > wrote: > >> > >> > Good point. Didn't know that. We can still add them for the release. > >> > > >> > On Sat, Oct 31, 2015 at 1:51 PM, Alexander Alexandrov > >> > <alexander.s.alexand...@gmail.com> wrote: > >> > > My two cents - there are already Maven artifacts deployed for 2.11 > in > >> the > >> > > SNAPSHOT repository. I think it might be confusing if they suddenly > >> > > disappear for the stable release. > >> > > > >> > > > >> > > 2015-10-29 11:58 GMT+01:00 Maximilian Michels <m...@apache.org>: > >> > > > >> > >> Seems like we agree that we need artifacts for different versions > of > >> > Scala > >> > >> on Maven. There also seems to be a preference for including the > >> version > >> > in > >> > >> the artifact name. > >> > >> > >> > >> I've created an issue and marked it to be resolved for 1.0. For the > >> 0.10 > >> > >> release, we will have binaries but no Maven artifacts. The biggest > >> > >> challenge I see is to remove Scala from as many modules as > possible. > >> For > >> > >> example, flink-java depends on Scala at the moment.. > >> > >> > >> > >> https://issues.apache.org/jira/browse/FLINK-2940 > >> > >> > >> > >> On Wed, Oct 28, 2015 at 7:31 PM, Frederick F. Kautz IV < > >> > fka...@redhat.com> > >> > >> wrote: > >> > >> > >> > >> > No idea if I get a vote ;) Nevertheless, +1 to have binaries for > >> both > >> > >> > versions in Maven and explicitly "scala versioned". > >> > >> > > >> > >> > Some background on this for those not as familiar with scala > >> > versioning: > >> > >> > > >> > >> > It's considered best practice to label what version of scala a > >> library > >> > >> > uses in the artifact id. > >> > >> > > >> > >> > The reason is compiled scala code is only compatible with the > major > >> > >> > version of scala it was compiled for. For example, a library > >> > compatible > >> > >> > with 2.10 is not compatible with 2.11. The same will be true with > >> 2.12 > >> > >> once > >> > >> > it is released. Mixing versions will result in undefined behavior > >> > which > >> > >> > will likely manifest itself as runtime exceptions. > >> > >> > > >> > >> > The convention to fix this problem is for all published > libraries to > >> > >> > specify the version of scala they are compatible with. Leaving > out > >> the > >> > >> > scala version in a library is akin to saying "We don't depend on > >> scala > >> > >> for > >> > >> > this library, so feel free to use whatever you want." Sbt users > will > >> > >> > typically specify the version of scala they use and tooling is > built > >> > >> around > >> > >> > ensuring consistency with the "%%" operator. > >> > >> > > >> > >> > E.g. > >> > >> > > >> > >> > scalaVersion := "2.11.4" > >> > >> > > >> > >> > // this resolves to to artifactID: "scalacheck_2.11" > >> > >> > libraryDependencies += "org.scalacheck" %% "scalacheck" % > "1.12.0" % > >> > >> "test" > >> > >> > > >> > >> > The most important part of this is that the scala version is > >> explicit > >> > >> > which eliminates the problem for downstream users. > >> > >> > > >> > >> > Cheers, > >> > >> > Frederick > >> > >> > > >> > >> > > >> > >> > On 10/28/2015 10:55 AM, Fabian Hueske wrote: > >> > >> > > >> > >> >> +1 to have binaries for both versions in Maven and as build to > >> > download. > >> > >> >> > >> > >> >> 2015-10-26 17:11 GMT+01:00 Theodore Vasiloudis < > >> > >> >> theodoros.vasilou...@gmail.com>: > >> > >> >> > >> > >> >> +1 for having binaries, I'm working on a Spark application > >> currently > >> > >> with > >> > >> >>> Scala 2.11 and having to rebuild everything when deploying > e.g. to > >> > EC2 > >> > >> >>> is a > >> > >> >>> pain. > >> > >> >>> > >> > >> >>> On Mon, Oct 26, 2015 at 4:22 PM, Ufuk Celebi <u...@apache.org> > >> > wrote: > >> > >> >>> > >> > >> >>> I agree with Till, but is this something you want to address in > >> this > >> > >> >>>> release already? > >> > >> >>>> > >> > >> >>>> I would postpone it to 1.0.0. > >> > >> >>>> > >> > >> >>>> – Ufuk > >> > >> >>>> > >> > >> >>>> On 26 Oct 2015, at 16:17, Till Rohrmann <trohrm...@apache.org > > > >> > wrote: > >> > >> >>>>> > >> > >> >>>>> I would be in favor of deploying also Scala 2.11 artifacts to > >> > Maven > >> > >> >>>>> > >> > >> >>>> since > >> > >> >>> > >> > >> >>>> more and more people will try out Flink with Scala 2.11. > Having > >> the > >> > >> >>>>> dependencies in the Maven repository makes it considerably > >> easier > >> > for > >> > >> >>>>> people to get their Flink jobs running. > >> > >> >>>>> > >> > >> >>>>> Furthermore, I observed that people are not aware that our > >> > deployed > >> > >> >>>>> artifacts, e.g. flink-runtime, are built with Scala 2.10. As > a > >> > >> >>>>> > >> > >> >>>> consequence, > >> > >> >>>> > >> > >> >>>>> they mix flink dependencies with other dependencies pulling > in > >> > Scala > >> > >> >>>>> > >> > >> >>>> 2.11 > >> > >> >>> > >> > >> >>>> and then they wonder that the program crashes. It would be, > imho, > >> > >> >>>>> > >> > >> >>>> clearer > >> > >> >>> > >> > >> >>>> if all our dependencies which depend on a specific Scala > version > >> > would > >> > >> >>>>> > >> > >> >>>> have > >> > >> >>>> > >> > >> >>>>> the corresponding Scala suffix appended. > >> > >> >>>>> > >> > >> >>>>> Adding the 2.10 suffix would also spare us the hassle of > >> upgrading > >> > >> to a > >> > >> >>>>> newer Scala version in the future, because then the artifacts > >> > >> wouldn't > >> > >> >>>>> share the same artifact name. > >> > >> >>>>> > >> > >> >>>>> Cheers, > >> > >> >>>>> Till > >> > >> >>>>> > >> > >> >>>>> On Mon, Oct 26, 2015 at 4:04 PM, Maximilian Michels < > >> > m...@apache.org> > >> > >> >>>>> > >> > >> >>>> wrote: > >> > >> >>>> > >> > >> >>>>> Hi Flinksters, > >> > >> >>>>>> > >> > >> >>>>>> We have recently committed an easy way to change Flink's > Scala > >> > >> >>>>>> > >> > >> >>>>> version. > >> > >> >>> > >> > >> >>>> The > >> > >> >>>> > >> > >> >>>>> question arises now whether we should ship Scala 2.11 as > >> binaries > >> > and > >> > >> >>>>>> > >> > >> >>>>> via > >> > >> >>>> > >> > >> >>>>> Maven. For the rc0, I created all binaries twice, for Scala > 2.10 > >> > and > >> > >> >>>>>> > >> > >> >>>>> 2.11. > >> > >> >>>> > >> > >> >>>>> However, I didn't create Maven artifacts. This follows our > >> current > >> > >> >>>>>> > >> > >> >>>>> shipping > >> > >> >>>> > >> > >> >>>>> strategy where we only ship Hadoop1 and Hadoop 2.3.0 Maven > >> > >> >>>>>> > >> > >> >>>>> dependencies > >> > >> >>> > >> > >> >>>> but > >> > >> >>>> > >> > >> >>>>> additionally Hadoop 2.4, 2.6, 2.7 as binaries. > >> > >> >>>>>> > >> > >> >>>>>> Should we also upload Maven dependencies for Scala 2.11? > >> > >> >>>>>> > >> > >> >>>>>> If so, the next question arises: What version pattern > should we > >> > have > >> > >> >>>>>> > >> > >> >>>>> for > >> > >> >>> > >> > >> >>>> the Flink Scala 2.11 dependencies? For Hadoop, we append > -hadoop1 > >> > to > >> > >> >>>>>> > >> > >> >>>>> the > >> > >> >>> > >> > >> >>>> VERSION, e.g. artifactID=flink-core, version=0.9.1-hadoop1. > >> > >> >>>>>> > >> > >> >>>>>> However, it is common practice to append the suffix to the > >> > >> artifactID > >> > >> >>>>>> > >> > >> >>>>> of > >> > >> >>> > >> > >> >>>> the Maven dependency, e.g. artifactID=flink-core_2.11, > >> > version=0.9.1. > >> > >> >>>>>> > >> > >> >>>>> This > >> > >> >>>> > >> > >> >>>>> has mostly historic reasons but is widely used. > >> > >> >>>>>> > >> > >> >>>>>> Whatever naming pattern we choose, it should be consistent. > I > >> > would > >> > >> be > >> > >> >>>>>> > >> > >> >>>>> in > >> > >> >>>> > >> > >> >>>>> favor of changing our artifact names to contain the Hadoop > and > >> > Scala > >> > >> >>>>>> version. This would also imply that all Scala dependent > Maven > >> > >> modules > >> > >> >>>>>> receive a Scala suffix (also the default Scala 2.10 > modules). > >> > >> >>>>>> > >> > >> >>>>>> Cheers, > >> > >> >>>>>> Max > >> > >> >>>>>> > >> > >> >>>>>> > >> > >> >>>> > >> > >> > > >> > >> > >> > > >> >
