I would like have a decision on this so that we can merge the pull request.
If we can not come up with a solution everybody agrees, and nobody rejects the VOTE, I'll start a VOTE thread in 24 hours. On Tue, Aug 9, 2016 at 3:57 PM, Till Rohrmann <trohrm...@apache.org> wrote: > That is a tough call but I'm personally leaning slightly towards not > breaking the API and adding a note for the casting workaround. > > My main concern is where do we set the limit for future API breaking > issues? How critical does an issue has to be to be allowed to break the > API? Currently, we have 10 API breaking issues for Flink 2.0 [1]. Why not > including one of them as well? > > I think that backwards compatibility (source as well as binary) is really > important for many users and we have the duty to live up to our promises. > Imho, if things are API breaking, then we should indeed bump the major > version, as Greg suggested. > > [1] https://issues.apache.org/jira/browse/FLINK-3957 > > Cheers, > Till > > On Tue, Aug 9, 2016 at 2:20 PM, Greg Hogan <c...@greghogan.com> wrote: > > > I agree that expecting users to cast is undesirable. Upon changing the > API, > > why would we not mark the next release as 2.0? > > > > The same issue arose with Gabor's addition of hash-combine in the Scala > > DataSet API where DataSet was returned rather than a specialized > Operator. > > The solution was to add an overloaded method. > > > > https://github.com/apache/flink/pull/1517/files#diff- > > b1fea8d5283d978e9ccbc202dad36b5fR322 > > > > On Mon, Aug 8, 2016 at 10:11 AM, Stephan Ewen <se...@apache.org> wrote: > > > > > Hi all! > > > > > > We have a problem in the *DataStream API* around Windows for *CoGroup* > > and > > > *Join*. > > > These operations currently do not allow to set a parallelism, which is > a > > > pretty heavy problem. > > > > > > To fix it properly, we need to change the return types of the coGroup() > > and > > > join() operations, which *breaks the binary compatibility* - it* > retains > > > source compatibility*, though. > > > > > > The pull request with the change is: > > > https://github.com/apache/flink/pull/2305 > > > > > > There are very clumsy ways to work around this (custom casts in the > user > > > code or making the join() / coGroup() behave differently than the other > > > operators) which we did not really think of as viable, because they > would > > > need to be changed again in the future once we pull the API straight > > > (breaking even source compatibility then). > > > > > > *I would suggest to actually break the API* at that point (binary, not > > > source) for *Flink 1.2* and add a big note in the release docs. An > > > uncomfortable step, but the alternatives are quite bad, too. > > > > > > Have a look at what has been suggested in the pull request discussion > and > > > please let us know what you think about that so we can proceed. > > > > > > Greetings, > > > Stephan > > > > > >
