I think not making the relevant APIs LP(Coprocessor) was an oversight. In my opinion we should do that. I'm not sure about Public. We could do that too but somewhere we need to call out that coprocessors have access to tags, but not clients. (Tags are removed at RPC except for replication.) LP doesn't imply what Public might.
> On Sep 22, 2017, at 9:11 AM, Andrew Purtell <[email protected]> wrote: > > Tags are server side internal metadata. Some carry sensitive information like > labels. I guess this could appear odd if not around for discussion when they > were introduced. So what documentation can be improved to lessen the > surprise? Javadoc? Online book? A JIRA with suggestions welcome. > > >> On Sep 22, 2017, at 9:07 AM, Josh Elser <[email protected]> wrote: >> >> I can appreciate how we've gotten to this point, it just struck me extremely >> odd that the contents of a Tag weren't expected to be accessed by users. >> "Arbitrary metadata that rides along with a cell, you just can't see that >> metadata" ;) >> >> I totally understand not wanting to let another thing come into 2.0. Like >> MikeD said, let's hope for a faster 3.0 and we can slate this for that time. >> >> Thanks for entertaining the discussion. We'll just deal with the "downstream >> pain" for 2.0. >> >>> On 9/22/17 1:32 AM, ramkrishna vasudevan wrote: >>> CellUtil similar type of methods. Coming to Tags yes there are not much >>> cases where clients can directly set Tags. And I think we don't expose any >>> APIs which allow you to use mutations with Tags. So probably moving to >>> LimitedPrivate is better and mark with Evolving if there are some users >>> depending on the internals of Tags and its impl. But this will be a One of >>> case. >>> And also since Tags are internal ideally the CellUtil#getTAgs() should have >>> been in another Util method that is exposed with LimitedPrivate and also >>> Tags if tags should be made LimitedPRivate. So this may help in not having >>> a PRivate interface like Tag in a public CellUtil class. >>> 3.0 is fine but need some clean up in 2.0? Indicating what could happen >>> going forward from 2.0? >>> Regards >>> Ram >>>> On Fri, Sep 22, 2017 at 2:59 AM, Sean Busbey <[email protected]> wrote: >>>> Yeah. I mean, I think we should improve the situation. Just think >>>> it's too much to bite off at this stage of 2.0, we can aim for 3.0 and >>>> start working in some tooling to help us. >>>> >>>>> On Thu, Sep 21, 2017 at 3:35 PM, Josh Elser <[email protected]> wrote: >>>>> That really makes me groan (we have downstream users depending on code >>>> we've >>>>> explicitly said "don't use"), but if that's what it is given the current >>>>> state, so be it. My complaining won't fix it. >>>>> >>>>> Thanks. >>>>> >>>>> >>>>>> On 9/21/17 4:25 PM, Sean Busbey wrote: >>>>>> >>>>>> We have lots of examples of including non-Public stuff in Public APIs. >>>>>> we have docs that advise folks to be wary on relying on them beyond >>>>>> opaque symbols. >>>>>> >>>>>> ref: http://hbase.apache.org/book.html#hbase.client.api.surface >>>>>> >>>>>>> On Thu, Sep 21, 2017 at 3:21 PM, Josh Elser <[email protected]> wrote: >>>>>>> >>>>>>> I was going to suggest LimitedPrivate in my original, but this doesn't >>>>>>> make >>>>>>> sense as we're exposing Public API via CellUtil. >>>>>>> >>>>>>> It seems odd to me that we wouldn't treat the cell tags as a supported >>>>>>> API >>>>>>> call. However, I'm happy to remain "confused" if the rest of folks >>>> don't >>>>>>> consider tags to be intended for users :) >>>>>>> >>>>>>> >>>>>>>> On 9/21/17 3:15 PM, Ted Yu wrote: >>>>>>>> >>>>>>>> >>>>>>>> Can we mark Tag LimitedPrivate ? >>>>>>>> >>>>>>>> We know how ATS uses Tags so it should be straight forward to keep >>>> their >>>>>>>> usage intact. >>>>>>>> >>>>>>>> On Thu, Sep 21, 2017 at 12:03 PM, Josh Elser <[email protected]> >>>> wrote: >>>>>>>> >>>>>>>>> Hiya, >>>>>>>>> >>>>>>>>> (Background, I'm starting what is likely to be an onerous task of >>>>>>>>> looking >>>>>>>>> through downstream components and seeing what is broken with the >>>> latest >>>>>>>>> hbase-2.0.0*) >>>>>>>>> >>>>>>>>> Looking at YARN's use of HBase for the Application TimelineServer, I >>>>>>>>> see >>>>>>>>> that they're relying on the Tag interface. >>>>>>>>> >>>>>>>>> Presently, Tag is marked as Private, yet we expose it via the Public >>>>>>>>> CellUtil. >>>>>>>>> >>>>>>>>> My gut reaction is that we should bump Tag up Public since the intent >>>>>>>>> is >>>>>>>>> for downstream users to, ya know, use those Tags. Any objections? >>>>>>>>> >>>>>>>>> If we don't want to expose Tag, we should make a pass over the Public >>>>>>>>> methods and mark them as Private (so not as to provide a Public >>>> method >>>>>>>>> with >>>>>>>>> Private objects). CellUtil#getTag(Cell, byte) would be one such >>>>>>>>> example. >>>>>>>>> >>>>>>>>> - Josh >>>>>>>>> >>>>>>>> >>>>>>> >>>>> >>>>
