Piotr, Based on the questions that we've seen over the past month on this list, there are still users with Solr on 6, 7, and 8. I suspect there are still Solr 5 users out there too, although they don't appear to be asking for help - likely they are in set it and forget it mode.
Solr 7 may not be officially deprecated on our site, but it's pretty old at this point and we're not doing any development on it outside of maaaaybe a very high profile security fix. Even then, we might acknowledge it and recommend users update to 8.x anyway. The index files generated by Lucene and consumed by Solr are backwards compatible up to one major version. Some of the API remains compatible, a client issuing simple queries to Solr 5 would probably work fine even against Solr 9 when it comes out eventually. A client doing admin operations will be less certain. I don't know enough about Beam to tell you where on the spectrum your use will fall. I'm not sure if this was helpful or not, but maybe it is a nudge in the right direction. Good luck, Mike On Tue, Oct 27, 2020 at 11:09 AM Piotr Szuberski < piotr.szuber...@polidea.com> wrote: > Hi, > > We are working on dependency updates at Apache Beam and I would like to > consult which versions should be supported so we don't break any existing > users. > > Previously the supported Solr version was 5.5.4. > > Versions 8.x.y and 7.x.y naturally come to mind as they are the only not > deprecated. But maybe there are users that use some earlier versions? > > Are these versions backwards-compatible or there are things to be aware of? > > Regards >