is there a reason we decided `def global subsystems ` was v1

Question

is there a reason we decided `def global subsystems ` was v1 only if i define a context aware object factory in my v2 ruleset which pulls in a subsystem using ` global instance ` i need that subsystem to be available i was able to overcome this by just registering it as a v1 plugin as well but unless we plan to literally deprecate ` global instance ` for v2 which it s not clear that we are it seems like we should allow `global subsystems` to be in v2 plugins as well

hundreds-father-404 · Answer

cc < happy kitchen 89482> He came upon this yesterday

hundreds-father-404 · Answer

It s possible that we want to keep the hook but don t document it so that we have more flexibility to remove later Personally I think it would be nice to remove ` global instance ` to simplify the Optionable code but I don t think anyone has any plans to do this yet

aloof-angle-91616 · Answer

i think it would be great to do that

hundreds-father-404 · Answer

which part does that refer to

aloof-angle-91616 · Answer

the second paragraph

hundreds-father-404 · Answer

I think the only blocker is not knowing how `object` and `CAFO` would access subsystems

aloof-angle-91616 · Answer

`SubsystemRule` or whatever it is now is just exactly what we need

aloof-angle-91616 · Answer

yea

aloof-angle-91616 · Answer

i was trying to think of whether i had run into literally the only edge case

aloof-angle-91616 · Answer

which i think i did with the CAOF to make different thrift libraries in the twitter repo

hundreds-father-404 · Answer

I don t think anyone has thought about what CAFO should look like DWH intentionally didn t try to replace it and wanted a light weight macro system to start

hundreds-father-404 · Answer

gt i was trying to think of whether i had run into literally the only edge case Agreed that I think object CAFO are the only remaining uses of ` global subsystem `

aloof-angle-91616 · Answer

i think we can deprecate our usage of CAOF and turn them into macros at twitter it s mainly the thrift libraries one and i think the new macro system can do everything except maybe access option values

hundreds-father-404 · Answer

We can t for Pants Pants depends on CAOF for `python requirements` and `pants requirement` And the new macros don t work there because the loading mechanism new macros are only internal to your own repo afaict

hundreds-father-404 · Answer

I think we need a modern replacement to CAOF We would have it for more advanced cases that the light weight macros can t cover

aloof-angle-91616 · Answer

i would prefer to have a single macro system

witty-crayon-22786 · Answer

aloof-angle-91616 · Answer

that is fantastically helpful thank you

aloof-angle-91616 · Answer

i think stu s issue link might be the way we can avoid making the macro system too heavyweight

witty-crayon-22786 · Answer

pretty stale lots has changed but `python requirements` is still the hold out

hundreds-father-404 · Answer

See <https github com pantsbuild pants pull 10231> Danny Good timing hehe