This is good discussion, I mentioned this in phoenix-dev that we need to repurpose coprocessors, and just give them put / get kind of injection points, but not allow co-processors to tap into log / compaction, etc. Those will be better served by explicitly defined plugins (like the recent StorageEngine, HLog, etc) that we explicitly allow injecting code with some API stability (though probably still evolving at a fast pace).
It would be good to have an idea of what classes / methods, phoenix and similar depend on HBase right now. Enis On Mon, Feb 10, 2014 at 6:04 PM, Jeffrey Zhong <jzh...@hortonworks.com>wrote: > > We need to revisit which interfaces should be marked as real "private" > because coprocessors allow custom applications to accesses internal > states. Current private interface such as KeyValue, WALEdit, Hregion, > HLogKey, Store etc is may used by custom coprocessor applications so any > public method signature change in those "private" interfaces possibliy > breaks custom coprocessor implementations. > > -Jeffrey > > On 2/10/14 4:59 PM, "lars hofhansl" <la...@apache.org> wrote: > > >True. But we can clearly annotate what is public and what is not. > >In HRegion we'd have to do it per method. It's probably easier to extract > >the public interface out into a Interface. (similar to Store and HStore) > >HBASE-4207 solves a slightly different problem. Here I want to have > >access to some HBase internals for performance, but I want to know what > >is public and stable and what I should not touch (thinking about things > >like Phoenix). > > > > > >-- Lars > > > > > > > >________________________________ > > From: Andrew Purtell <apurt...@apache.org> > >To: "dev@hbase.apache.org" <dev@hbase.apache.org> > >Sent: Monday, February 10, 2014 4:46 PM > >Subject: Re: DISCUSSION: 1.0.0 > > > > > >On Mon, Feb 10, 2014 at 4:42 PM, lars hofhansl <la...@apache.org> wrote: > > > > > >> + known coprocessor interfaces. For example right now a coprocessor can > >> use everything on HRegion. We need to distill what's useful into an > >> interface. > > > > > >We started this with Environment and the HTable wrapper as an example of > >how to wrap an interface for CPs. At the end of the day we can't stop a > >coprocessor from accessing internal objects and calling their methods > >directly until HBASE-4047. (Maybe that makes the 1.0 list?) > > > >Related, paring down the coprocessor interfaces to only intercept RPC > >based > >actions and move everything else to plugins. > > > > > > > >-- > >Best regards, > > > > - Andy > > > >Problems worthy of attack prove their worth by hitting back. - Piet Hein > >(via Tom White) > > > > -- > CONFIDENTIALITY NOTICE > NOTICE: This message is intended for the use of the individual or entity to > which it is addressed and may contain information that is confidential, > privileged and exempt from disclosure under applicable law. If the reader > of this message is not the intended recipient, you are hereby notified that > any printing, copying, dissemination, distribution, disclosure or > forwarding of this communication is strictly prohibited. If you have > received this communication in error, please contact the sender immediately > and delete it from your system. Thank You. >
