Hi Tal, Thanks for feedback. PersistentView will remain until Persistence Query and Streams are non-experimental. It will exist for the full 2.4.x lifecycle. We will not remove it without a replacement, i.e. if journal plugins don't implement corresponding query we have failed and must revert the decision to eventually remove PersistentView.
Remember that Akka Persistence (and PersistentView) is experimental in 2.3.x. We use the experimental marker to make it possible to change the API based on feedback, and we got a lot of feedback around that PersistentView was not powerful enough, rightfully so. Therefore we created Persistence Query and are slowly phasing out PersistentView. Regards, Patrik On Mon, Sep 7, 2015 at 4:06 PM, Tal Pressman <kir...@gmail.com> wrote: > Hi, > > Akka 2.4 is coming, bringing with it Persistence Queries, which for the > most part look really great. However, there are some issues with it that I > find problematic. > > The first regards dependencies - 2.4.0 deprecates PersistentView, but the > recommended classes are part of an entirely different module, and that is > still experimental. On top of that, the new module depends on the stream > module, which is itself experimental. So what is someone more conservative > supposed to use? > > The second issue is about migration from 2.3 to 2.4. In our application, > for example, we created stream Sources that wrap a PersistentView. > Obviously, there are a lot of drawbacks to this approach compared to the > Query approach, but there are advantages as well (for example: we don't > care which persistence plugin is used, and we know exactly which "queries" > are supported - all events belonging to a persistenceId). > Now, if we decide to migrate to 2.4, "our" classes become deprecated (or > rather, use deprecated APIs). We could switch to a Query-based > implementation, but then we have to contend with the issue of when (if at > all) plugins are updated to support the new API. > > Bottom line, the way it looks right now, it would be hard for me to > justify switching over to using the new query API at the moment (even > though I *really* want to), so at least I hope PersistentViews won't go > anywhere anytime soon. > > Tal > > -- > >>>>>>>>>> Read the docs: http://akka.io/docs/ > >>>>>>>>>> Check the FAQ: > http://doc.akka.io/docs/akka/current/additional/faq.html > >>>>>>>>>> Search the archives: https://groups.google.com/group/akka-user > --- > You received this message because you are subscribed to the Google Groups > "Akka User List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to akka-user+unsubscr...@googlegroups.com. > To post to this group, send email to akka-user@googlegroups.com. > Visit this group at http://groups.google.com/group/akka-user. > For more options, visit https://groups.google.com/d/optout. > -- Patrik Nordwall Typesafe <http://typesafe.com/> - Reactive apps on the JVM Twitter: @patriknw -- >>>>>>>>>> Read the docs: http://akka.io/docs/ >>>>>>>>>> Check the FAQ: >>>>>>>>>> http://doc.akka.io/docs/akka/current/additional/faq.html >>>>>>>>>> Search the archives: https://groups.google.com/group/akka-user --- You received this message because you are subscribed to the Google Groups "Akka User List" group. To unsubscribe from this group and stop receiving emails from it, send an email to akka-user+unsubscr...@googlegroups.com. To post to this group, send email to akka-user@googlegroups.com. Visit this group at http://groups.google.com/group/akka-user. For more options, visit https://groups.google.com/d/optout.
