Pluggable intervals

[mattweber]

Is your feature request related to a problem? Please describe.
Make intervals pluggable so users can write custom intervals in search plugins.

Describe the solution you'd like
Add a plugin api that allows a user to register new intervals with named writable and named xcontents which can ultimately be used in interval queries.

Describe alternatives you've considered
Exposing more of the lucene interval functionality explicitly, see #1857 and #1858.

Additional context
A lot of functionality in open search is pluggable (queries, aggregations, suggesters, etc) and it would be great to add plugin points so users can add functionality that might never make it upstream.

[mattweber]

FYI, I have done this for elasticsearch and can rework it for open search. I believe that if users are smart enough to write their own plugin they are smart enough to follow the expected behaviors of the api (minimal intervals, etc). Elastic did not believe that and thus the reason the PR was never accepted.

[anasalkouz]

@nknize Could you look into this issue?

[saratvemulapalli]

@mattweber sounds like the right way to approach it. Are you open to re-write this for opensearch?

[saratvemulapalli]

@mattweber gentle ping again :)

[dbwiddis]

@mattweber another gentle ping! :)

[mattweber]

@saratvemulapalli @dbwiddis sorry for delay, yes I can work on this. In the process of a big move so once I get settled I will work on it.