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 >> > >> >>>>>> >> > >> >>>>>> >> > >> >>>> >> > >> > >> > >> >> > >>
