Hi Martjin, After some more careful consideration I am in favor of dropping the Scala API support in with Flink 2.0 given that we add Java 17 support earlier or latest at the same time.
Best, Marton On Thu, Oct 13, 2022 at 12:01 PM Chesnay Schepler <ches...@apache.org> wrote: > Support for records has not been investigated yet. We're still at the > stage of getting things to run at all on Java 17. > > It _may_ be possible, it _may_ not be. > > On 13/10/2022 07:39, Salva Alcántara wrote: > > Hi Martijn, > > Maybe a bit of an off-topic, but regarding Java 17 support, will it be > possible to replace POJOs with Java records in existing applications? > > In a project I maintain we use Lombok a lot, but with Java records we > would probably stop using it (or significantly reduce its usage). > > Will there be a way to promote existing POJOs (either written "manually" > or using Lombok) to Java records without breaking serialization? (assuming > that those POJOs are used as immutable values, e.g., setters are never > used). > > Regards, > > Salva > > On Wed, Oct 12, 2022 at 9:11 PM Martijn Visser <martijnvis...@apache.org> > wrote: > >> Hi everyone, >> >> Thanks again for all your feedback. It's very much appreciated. >> >> My overall feeling is that people are not opposed to the FLIP. There is >> demand for adding Java 17 support before dropping the Scala APIs. Given >> that the proposal for actually dropping the Scala APIs would only happen >> with a Flink 2.0 and Java 17 support would either happen in a new minor >> version or a new major version (I haven't seen a FLIP or discussion being >> opened adding Java 17 support, only on deprecating Java 8), Java 17 support >> would either be there earlier (in a new minor version) or at the same time >> (with Flink 2.0) when the Scala APIs would be dropped. >> >> If there are no more discussion topics, I would move this FLIP to a vote >> at the beginning of next week. >> >> Best regards, >> >> Martijn >> >> On Sun, Oct 9, 2022 at 10:36 AM guenterh.lists <guenterh.li...@bluewin.ch> >> wrote: >> >>> Hi Martijn >>> >>> I do not maintain a large production application based on Flink, so it >>> would not be a problem for me to convert existing implementations to >>> whatever API. >>> >>> I am working in the area of cultural heritage, which is mainly about the >>> processing of structured (meta)-data (scientific libraries, archives and >>> museums) >>> My impression: People without much background/experience with Java >>> implementations find it easier to get into the functional mindset as >>> supported in Scala. That's why I think it would be very unfortunate if the >>> use of Scala in Flink becomes more and more limited or neglected. >>> >>> I think using the Java API in Scala is a possible way also in my >>> environment. >>> >>> In the last weeks I tried to port the examples from the "Flink Course" >>> of Daniel Ciorcilan (https://rockthejvm.com/p/flink - he mainly offers >>> Scala courses), which are exclusively based on the native Scala API, to the >>> Java API. This has worked without any problems as far as I can see. So far >>> I haven't tried any examples based on the Table API or streaming workflows >>> in batch mode (which would be important for our environment). >>> >>> My main trouble: So far I don't know enough about the limitations of >>> using the Java API in a Scala implementation and what that means. My >>> current understanding: the limitation is mainly in deriving the type >>> information in generic APIs with Scala types. For me it would be very >>> significant and helpful if there would be more information, descriptions >>> and examples about this topic. >>> >>> So far unfortunately I had too little time to deal with a wrapper like >>> flink-scala-api (https://github.com/findify/flink-scala-api ) and the >>> current alternative is probably going to be deprecated in the future ( >>> https://github.com/ariskk/flink4s/issues/17#issuecomment-1125806808 ) >>> >>> Günter >>> >>> >>> On 04.10.22 13:58, Martijn Visser wrote: >>> >>> Hi Marton, >>> >>> You're making a good point, I originally wanted to include already the >>> User mailing list to get their feedback but forgot to do so. I'll do some >>> more outreach via other channels as well. >>> >>> @Users of Flink, I've made a proposal to deprecate and remove Scala API >>> support in a future version of Flink. Your feedback on this topic is very >>> much appreciated. >>> >>> Regarding the large Scala codebase for Flink, a potential alternative >>> could be to have a wrapper for all Java APIs that makes them available as >>> Scala APIs. However, this still requires Scala maintainers and I don't >>> think that we currently have those in our community. The easiest solution >>> for them would be to use the Java APIs directly. Yes it would involve work, >>> but we won't actually be able to remove the Scala APIs until Flink 2.0 so >>> there's still time for that :) >>> >>> Best regards, >>> >>> Martijn >>> >>> On Tue, Oct 4, 2022 at 1:26 AM Márton Balassi <balassi.mar...@gmail.com> >>> wrote: >>> >>>> Hi Martjin, >>>> >>>> Thanks for compiling the FLIP. I agree with the sentiment that Scala >>>> poses >>>> considerable maintenance overhead and key improvements (like 2.13 or >>>> 2.12.8 >>>> supports) are hanging stale. With that said before we make this move we >>>> should attempt to understand the userbase affected. >>>> A quick Slack and user mailing list search does return quite a bit of >>>> results for scala (admittedly a cursory look at them suggest that many >>>> of >>>> them have to do with missing features in Scala that exist in Java or >>>> Scala >>>> versions). I would love to see some polls on this topic, we could also >>>> use >>>> the Flink twitter handle to ask the community about this. >>>> >>>> I am aware of users having large existing Scala codebases for Flink. >>>> This >>>> move would pose a very large effort on them, as they would need to >>>> rewrite >>>> much of their existing code. What are the alternatives in your opinion, >>>> Martjin? >>>> >>>> On Tue, Oct 4, 2022 at 6:22 AM Martijn Visser <martijnvis...@apache.org >>>> > >>>> wrote: >>>> >>>> > Hi everyone, >>>> > >>>> > I would like to open a discussion thread on FLIP-265 Deprecate and >>>> remove >>>> > Scala API support. Please take a look at >>>> > >>>> > >>>> https://cwiki.apache.org/confluence/display/FLINK/FLIP-265+Deprecate+and+remove+Scala+API+support >>>> > and provide your feedback. >>>> > >>>> > Best regards, >>>> > >>>> > Martijn >>>> > https://twitter.com/MartijnVisser82 >>>> > https://github.com/MartijnVisser >>>> > >>>> >>> -- >>> Günter Hipler >>> University library Leipzig >>> >>> >
